Terphenyl, hydrogenated

Endpoint summary

Description of key information

Terphenyl, hydrogenated was tested for repeated dose toxicity in various species, including rats, rabbits and mice. NOAELs were defined in the various studies for oral (nominal 12 mg/kg, corresponding to 14.8 mg/kg actual ingested for males and 17.0 mg/kg actual ingested for females), dermal (2000 mg/kg) and inhalation administration route (100 mg/m³).

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP-compliant EPA guideline study, available as unpublishedd report, no restrictions, adequate for assessment.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 408 (Repeated Dose 90-Day Oral Toxicity Study in Rodents)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.8700 (Subchronic Oral Toxicity Test)

Deviations:

no

GLP compliance:

yes

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Breeding Laboratories, Inc., Kingston, New York 12484
- Age at study initiation: 43 days old
- Weight at study initiation: 197 grams for males (173-213) and 157 grams for females (131-175)
- Housing: doubly housed
- Diet (e.g. ad libitum): ad libitum; standard laboratory diet (Purina certified rodent chow #5002)
- Water (e.g. ad libitum): ad libitum; (Elizabethtown water company)
- Acclimation period: 14 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 61-75°F
- Humidity (%): 15-65%
- Photoperiod (hrs dark / hrs light): 12 hour light/dark cycle (7 am to 7 pm)

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

DIET PREPARATION
- Rate of preparation of diet (frequency): weekly
- Mixing appropriate amounts with (Type of food): standard laboratory diet (Purina certified rodent chow #5002)

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Four ouce samples were taken for the control group and each dose level weekly and were stored frozen at Bio/dynamics, Inc. Duplicate samples were taken for weeks 1, 2, 3, 4, 6, 8, 10 and 12 and analyses for concentration were performed by the Department of Metabolism and Analytical Chemistry of Bio/dynamics, Inc.

Duration of treatment / exposure:

14 weeks

Frequency of treatment:

7 days/week

Dose / conc.:

0 ppm

Remarks:

nominal in diet, corresponding to 0 mg/kg bw/d

Dose / conc.:

50 ppm

Remarks:

nominal in diet, corresponding to 3 mg/kg bw/d (nominal) and 3.6 mg/kg/d (Males; actual ingested) and 4.2 mg/kg/d (Females; actual ingested)

Dose / conc.:

200 ppm

Remarks:

nominal in diet, corresponding to 12 mg/kg bw/d (nominal) and 14.8 mg/kg/d (Males; actual ingested) and 17.0 mg/kg/d (Females; actual ingested)

Dose / conc.:

2 000 ppm

Remarks:

nominal in diet, corresponding to 120 mg/kg bw/d (nominal) and 143.7 mg/kg/d (Males; actual ingested) and 169.2 mg/kg/d (Females; actual ingested)

No. of animals per sex per dose:

12 animals per sex per dose

Control animals:

yes

Observations and examinations performed and frequency:

OBSERVATIONS FOR MORTALITY AND GROSS SIGNS OF TOXICOLOGIC OR PHARMACOLOGIC EFFECTS: Yes
- Time schedule: Twice daily, once in the morning and once in the afternoon

DETAILED PHYSICAL EXAMINATION FOR SIGNS OF LOCAL OR SYSTEMIC TOXICITY? PHARMACOLOGIC EFFECTS AND PALPATION FOR TOSSUE MASSES: Yes
- Time schedule: Twice pretest and weekly thereafter

BODY WEIGHT: Yes
- Time schedule for examinations: twice pretest, weekly during treatment and terminally (after fasting)

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption determined : Yes; weekly, beginning one week prior to treatment
- Compound intake calculated : Yes; calculated from food consumption data and based on nominal concentrations

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: once pretest and at study termination
- Dose groups that were examined: all animals

HAEMATOLOGY: Yes
- Time schedule for collection of blood: at approximately 1 month and at study termination
- Anaesthetic used for blood collection: Yes (light ether anesthesia)
- Animals fasted: Yes
- How many animals: 10 animals per sex per group
- Parameters checked in Table 1 were examined.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: at approximately 1 month and at study termination
- Animals fasted: Yes
- How many animals: 10 animals per sex per group
- Parameters checked in Table 2 were examined.

Sacrifice and pathology:

GROSS PATHOLOGY: Yes (see Table 3)
HISTOPATHOLOGY: Yes (see Table 4)

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

effects observed, treatment-related

Food consumption and compound intake (if feeding study):

no effects observed

Food efficiency:

not specified

Water consumption and compound intake (if drinking water study):

not specified

Ophthalmological findings:

no effects observed

Haematological findings:

effects observed, treatment-related

Clinical biochemistry findings:

effects observed, treatment-related

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

not examined

Details on results:

CLINICAL SIGNS AND MORTALITY:
Physical observations noted in control and treated animals included alopecia, chromodacryorrhea and excessive lacrimation. These observations occured sporadically in control and treated animals. These incidences did not exhibit a dose-response and were not considered related to the administration of the test material. These findings are not uncommon in laboratory rats and may suggest the presence of a sialodacryoadenitis infection in these animals.
All control and treated animals survived the duration of the study.

BODY WEIGHT AND WEIGHT GAIN
The mean body weights of the treated males from all groups were unremarkable throughout the study when compared to the controls.
The mean body weights of the high-dose females (Group IV - 2000 ppm) were slightly (3-7%) lower than control throughout the treatment period. While the differences from control were small, they were consistent over time and were therefore attributed to the administration of the test material.
The mean body weights of the low- and mid-dose females were comparable to the controls throughout the study.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
The mean food consumption values of the high-dose males and females were slightly lower than control during the first week of the study. In addition, feed spillage was noted more frequently in the mid- and high-dose males than in the control males. These findings (decreased food consumption and spillage) may suggest a palatability problem with this material.
Food consumption data was unremarkable for the males and females for the remainder of the treatment-period.

OPHTHALMOSCOPIC EXAMINATION:
There were no ophthalmoscopic findings noted in the treated animals at study termination which were considered related to the administration of the test material.

HAEMATOLOGY:
The high-dose males, at the 1 month bleeding interval, exhibited slight decreases in mean hemoglobin concentration, hematocrit and erythrocyte counts and a slight increase in mean platelet count, these findings were statistically significant. At termination the high-dose males continued to exhibit slight (not statistically significant) decreases in mean hemoglobin concentration, hematocrit and erythrocyte count and a statistically significant increase in mean platelet count. While differences from control were slight the consistency of these findings at month 1 and study termination suggests a relationship to the administration of the test material.
Hematology data was unremarkable in the low- and mid-dose males and in all treated females at 1 month and at study termination.

CLINICAL CHEMISTRY:
The high-dose males exhibited slight, statistically significant elevations in mean cholesterol levels at month 1 and termination. In addition, the mean albumin level of the high-dose males was significantly elevated at study termination. The high-dose females exhibited a slight (statistically significant) reduction in mean glucose levels at month 1 and at study termination (not statistically significant).
The mid- and high-dose females exhibited slight (statistically significant) increases in mean calcium levels at 1 month. Slight (not statistically significant) increases were also noted in the mean calcium level of the mid- and high-dose females at study termination.

ORGAN WEIGHTS:
The high-dose males and females exhibited statistically significant increases in kidney to body weight ratios and slight (not statistically significant) increases in mean kidney weights and kidney to brain weight ratios. These increases were possibly related to slight decreases in mean terminal body weights in the high-dose males (2.5%) and females (6.4%). The high-dose males and females also exhibit significant increases in mean liver weights (47% and 21%), liver to body weight ratios (51% and 29%), and liver to brain weight ratios (49 and 22%). The high-dose females exhibited slight increases in mean adrenal weights, adrenal to body weight ratios and adrenal to brain weight ratios. Similar adrenal weight findings were not noted in the treated males.

GROSS PATHOLOGY:
There was no indication that the gross tissue changes noted during necropsy were treatment associated. Often the gross observations were related to normal color or architectural tissue pattern variations which had no microscopic correlation. Other tissue lesions were sporadic in occurrence or were of the type commonly encountered in laboratory rats of this age group. The were judged to have had no treatment relationship.

HISTOPATHOLOGY: NON-NEOPLASTIC
Microscopic assessment of the tissues revealed no histomorphological evidence of a direct treatment associated toxicopathological effect. There was noted, however, an increased incidence of a spontaneously occuring renal lesions when kidneys from high-dose male rats were compared to those of the male controls.

The minimal lesion was one which has been noted frequently in control male animals and was characterized by single or multiple small foci of proximal tubule epithelial cell hypertrophy and basophillia. These foci were interpreted as representing young regenerative cells. The exact cause of the lesion is obscure. In this study the regenerative foci were noted in 10 of 12 high-dose males and 4 of 12 control males. Similar foci were noted in 5 of 12 mid- and 5 of 12 low-dose rats. The renal lesion was not present in females except for 2 of 12 mid-dose animals.

Although the incidence was increased in high-dose males, the severity of the lesion was comparable to that noted in control males.

An increased of this spontaneous renal lesion in male rats treated with various other non-related compounds has been observed on previous occasions. The pathogenesis and biological significance of the lesion remains unclear.

Various other tissue alterations were noted in rats of both the control and treated groups. They occurred sporadically or with approximately equal frequency and degree in control rats as in treated animals and were judged to have no treatment relationship.

Under the conditions of this test, the following conclusions were made based on the gross and microscopic evaluation:
1. Terphenyl, hydrogenated when fed in the diet caused no specific toxicoppathological alteration in the tissues of male or female rats.
2. Terphenyl, hydrogenated high-dose treated male rats had an increased incidence but no increased severity of a spontaneously occuring regenerative renal lesion which was also present in the control males. The change was not present in high-dose females. The toxicopathological significance of the increased incidence in high-dose males when compared to control males was unclear.

A gross and microscopic correlation of lesions noted at necropsy revealed no evidence of a treatment associated response. No gross or microscopic pathology was noted which would correlate with the increased kidney and liver weights seen in the high-dose and/or females.

Microscopic evaluation of the tissues revealed no histomorphological evidence of a direct toxicopathological effect. Tissues from control rats were comparable to those from the treated animals.

There was, however, an increased incidence of a spontaneously occurring renal tubular lesion in high-dose males when compared to control males. the lesion incidence in low- and mid-dose males was similar to that observed in controls. Females were essentially free of the lesion. The ethiology and toxicopathological significance of the increased incidence rate in high-dose males was unclear.

Dose descriptor:

NOAEL

Effect level:

12 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

clinical biochemistry

clinical signs

food consumption and compound intake

gross pathology

haematology

mortality

ophthalmological examination

organ weights and organ / body weight ratios

Dose descriptor:

NOAEL

Effect level:

14.8 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male

Basis for effect level:

body weight and weight gain

clinical biochemistry

clinical signs

food consumption and compound intake

gross pathology

haematology

mortality

ophthalmological examination

organ weights and organ / body weight ratios

Remarks on result:

other: analytically verified

Dose descriptor:

NOAEL

Effect level:

17 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

female

Basis for effect level:

body weight and weight gain

clinical biochemistry

clinical signs

food consumption and compound intake

gross pathology

haematology

mortality

ophthalmological examination

organ weights and organ / body weight ratios

Remarks on result:

other: analytically verified

Dose descriptor:

LOAEL

Effect level:

120 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

clinical biochemistry

clinical signs

food consumption and compound intake

gross pathology

haematology

mortality

ophthalmological examination

organ weights and organ / body weight ratios

Critical effects observed:

not specified

Conclusions:

NOAEL = 200 ppm (nominal 12 mg/kg body weight/day, after analytical verification corresponding to 14.8 mg/kg bw/day in males and 17.9 mg/kg bw/day in females)

Executive summary:

Terphenyl, hydrogenated heat transfer fluid was administered orally, via dietary mixture to 72 Sprague-Dawley CD rats (12/sex/group) at dose levels of 50, 200 and 2000 ppm in the diet for a period of approximately 14 weeks, corresponding with nominal doses of 3, 12 and 120 mg/kg body weight/day. Control animals (12/sex/group) received a standard laboratory diet. Physical observations, ophtalmoscopic examinations, body weight and food consumption measurements were performed on all animals at selected intervals during the treatment period. Hematology and clinical chemistry evaluations were performed on 10 animals/sex/group at approximately 1 month and at study termination. After approximately 14 weeks of treatment, all survivors were sacrificed, selected organs were weighed and organ/body and organ/brain weight ratios calculated. Complete gross postmortem examinations were conducted on all animals. Histopathological evaluations were conducted on specified tissues for all animals in Group I (0 ppm) and IV ( 2000 ppm). Lungs, liver and kidneys were evaluated from all animals in Groups II (50 ppm) and III (200 ppm). All rats survived the 3-month test. The mean body weights of the high-dose females (Group IV – 2000 ppm) were slightly (3-7%) lower than control throughout the treatment-period. The mean food consumption values of high-dose males and females were slightly lower than control during the first week of the study and were unremarkable for the remainder of the treatment-period. The high-dose males, at the 1 month and terminal bleeding intervals exhibited slight decrease in mean hemoglobin concentration, hematocrit and erythrocyte counts and a slight increase in mean platelet count. While differences from control were slight the consistency of these findings at Month 1 and study termination suggests a relationship to administration of the test material. The high-dose males exhibited slight, statistically significant elevations in mean cholesterol levels at month 1 and termination. In addition, the mean albumin level of the high-dose males was significantly elevated at study termination. The high-dose females exhibited a slight (statistically significant) reduction in mean glucose levels at month 1 and at study termination (not statistically significant). The mid- and high-dose females exhibited slight (statistically significant) increases in mean calcium levels at 1 month. Slight (not statistically significant) increases were also noted in the mean calcium level of the mid- and high-dose females at study termination. A gross and microscopic correlation of lesions noted at necropsy revealed no evidence of a treatment associated response. Microscopic evaluation of the tissues revealed no histomorphical evidence of a direct toxicopathological effect. Tissues from control rats were comparable to those from the treated animals. There was, however, an increased incidence of a spontaneously occurring renal tubular lesions in high dose males when compared to control males. The lesion incidence in low and mild dose males was similar to that observed in controls. Females were essentially free of the lesion. The etiology and toxicopathological significance of the increased incidence rate in high dose males was unclear. Various other tissue alterations were encountered; however, they occurred sporadically or with approximately equal frequency and degree in control rats as in treated animals. They were judged to have had no treatment relationship. NOAEL was therefore set at 200 ppm in the diet, corresponding to nominal 12 mg/kg body weight/day which was shown to be after analytical verification 14.8 mg/kg bw7day in males and 17.0 mg/kg bw/day in females.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

NOAEL

14.8 mg/kg bw/day

Study duration:

subchronic

Species:

rat

System:

other: not stated

Repeated dose toxicity: inhalation - systemic effects

Link to relevant study records

Reference

Endpoint:

sub-chronic toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP-compliant study, available as unpublished report, well-documented, no restrictions, adequate for assessment.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 413 (Subchronic Inhalation Toxicity: 90-Day Study)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Breeding Laboratories, Inc., Wilmington, Massachusetts 01887
- Age at study initiation: 9 weeks (males) and 8 weeks (females)
- Weight at study initiation: 319 gr for males (300-339) and 192 gr for females (175-208)
- Housing: doubly housed during the first week then individually housed
- Diet (e.g. ad libitum): ad libitum (Standard laboratory diet) during acclimation period; None during exposure period
- Water (e.g. ad libitum): ad libitum during acclimation period; None during exposure period
- Acclimation period: 21/22 days (4 to 25/26 September 1984)

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21-31 °C
- Humidity (%): 24-95% (R.H.)
- Photoperiod (hrs dark / hrs light): 12 hour light/dark cycle (7am to 7 pm)

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

whole body

Vehicle:

other: unchanged (no vehicle)

Remarks on MMAD:

MMAD / GSD: Batelle cascade impactor:
MMAD (microns): 1.9, 1.8, 1.6 for groups exposed to 10, 100 ang 500 mg/m³ respectively.
GSD: 2.0, 1.8, 1.9 for groups exposed to 10, 100 ang 500 mg/m³ respectively.

TSI model:
MMAD (microns): 3.1, 2.0, 4.7 for groups exposed to 10, 100 ang 500 mg/m³ respectively.
GSD: 1.9, 1.9, 2.8 for groups exposed to 10, 100 ang 500 mg/m³ respectively.

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Chamber volume: one cubic meter
- Effective volume: 760 liters
- Air flow rate: average of 200 liters per minute (1 ppm)
- Air change rate: one complete air change every 5 minutes (average)
- Method of particle size determination: Using a Batelle cascade impactor and a TSI model 3300/3302 Aerodynamic Particle Sizer.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Exposure levels were determined by gas chromatographic assay (GC) of samples collected on filters. Concentration was also monitored gravimetrically as a secondary assay. In addition, distribution samples were taken at least three times during the study from four locations in the chamber for each group and assayed by GC.

Duration of treatment / exposure:

90 days

Frequency of treatment:

6 hours/day, 5 days/week (67 number of exposures per group/sex)

Dose / conc.:

0 mg/m³ air

Dose / conc.:

10 mg/m³ air

Remarks:

corresponding to 11.4 mg/m³ (males) and 11.3 mg/m³ (females)

Dose / conc.:

100 mg/m³ air

Remarks:

corresponding to 98.7 mg/m³ (males) and 98.4 mg/m³ (females)

Dose / conc.:

500 mg/m³ air

Remarks:

corresponding to 480 mg/m³ (males) and 479 mg/m³ (females)

No. of animals per sex per dose:

15 animals per sex per group

Control animals:

yes

Observations and examinations performed and frequency:

MORTALITY AND GROSS SIGNS OF TOXICOLOGIC OR PHARMACOLOGIC EFFECT:
- Time schedule: twice daily

DETAILED PHYSICAL OBSERVATIONS: Yes
- Time schedule: once a week

BODY WEIGHT: Yes
- Time schedule for examinations: Recorded pretest, weekly during the study and at termination.

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: pretest and at termination

HAEMATOLOGY: Yes
- Time schedule for collection of blood: at midterm and after the sixty-fifth exposure (males) and sixty-fourth exposure (females)
- Anaesthetic used for blood collection: Yes (identity): light ether anesthesia.
- Animals fasted: Yes
- How many animals: 40 animals (10/sex/group)
- Parameters checked in Table 1 were examined.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: at midterm and after the sixty-fifth exposure (males) and sixty-fourth exposure (females)
- Animals fasted: Yes
- How many animals: 40 animals (10/sex/group)
- Parameters checked in Table 2 were examined.

Sacrifice and pathology:

GROSS PATHOLOGY: Yes (see Table 3)
HISTOPATHOLOGY: Yes (see Table 4)

Clinical signs:

effects observed, treatment-related

Mortality:

mortality observed, treatment-related

Body weight and weight changes:

effects observed, treatment-related

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

no effects observed

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

not examined

Details on results:

CLINICAL SIGNS AND MORTALITY:
One Group I (control) female and one Group II (10 mg/m³) female died spontaneously during the study. Two Group II females and one Group IV (500 mg/m³) female died accidentally during blood collection. The one Group II female's spontaneous death did not appear to be treatment related.

Increased incidences of chromodacryorrhea, excess lacrimation and rough coat were exhibited by all groups of treated males compared to control males. The increased incidence of rough coat noted in the treated males did not appear to correlate with the presence of test material on the fur. Increased incidences of dried brown material around the facial area were exhibited by all treated groups of females compared to control females. These findings were considered to be treatment related.

BODY WEIGHT AND WEIGHT GAIN:
The mean body weights were decreased approximately 8% for the Group IV males during the study compared to the control males. The differences between Group IV and control males were considered suggestive of a treatment related effect. Comparisons between body weights for Group II and III (100 mg/m³) males and all groups of treated females, and the respective control animals were considered unremarkable.

OPHTHALMOSCOPIC EXAMINATION:
The following findings were noted at the terminal ophthalmology examination: proptosis and corneal necrosis (unilateral, 1 Group II male), conjunctivitis secondary to infectious disease or dental abnormality (unilateral, 1 Group IV male), retinal degeneration (bilateral, 1 Group I female) and phthisis bulbi which was secondary trauma or endophthalmitis (unilateral, 1 Group I female and 1 Group III female). These findings were not considered treatment related.

HAEMATOLOGY:
Haematology results were considered unremarkable.

CLINICAL CHEMISTRY:
The mean serum glutamic oxaloacetic transaminase and glucose levels were decreased for the Group IV females compared to the control females, and the mean total protein, albumin and calcium levels were increased for Group III and IV females compared to control females. Because the findings followed a pattern related to exposure concentration for Group III and IV females, these differences appeared to be treatment related. However, the majority of values were within historical control ranges and the nature of changes is not suggestive of an adverse effect. The absence of supporting microscopic lesions or organ weight findings in the liver, heart or other tissues suggests these clinical chemistry differences were insufficient to be considered toxicologically significant.
The mean blood urea nitrogen level was increased for Group IV males at Test Week 14 compared to control males. However, values were within historical ranges and no renal pathology was seen. Therefore, this difference is not considered to be toxicologically significant.

ORGAN WEIGHTS:
The mean absolute and relative liver weights were increased for all groups of treated males compared to control males. The differences between treated and control males were statistically significant for all comparisons except for the absolute liver weights of Group II and III males. These findings were considered treatment related. Mean absolute and relative liver weights were unremarkable in the treated females. There were no other findings in the organ weight data of the males or females which were attributed to the test material.

GROSS PATHOLOGY & HISTOPATHOLOGY (NON-NEOPLASTIC)
Postmortem findings, observed grossly and microscopically, either occurred in the treated and control animals with comparable incidence and severity or they occurred sporadically. These findings did not appear to be related to the test article.

Dose descriptor:

NOAEL

Effect level:

0.1 mg/L air

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

clinical biochemistry

clinical signs

gross pathology

haematology

mortality

ophthalmological examination

organ weights and organ / body weight ratios

Dose descriptor:

LOAEL

Effect level:

0.5 mg/L air

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

clinical biochemistry

clinical signs

gross pathology

haematology

mortality

ophthalmological examination

organ weights and organ / body weight ratios

Critical effects observed:

not specified

1) 0.01 mg/L
liver, weight, incr, M;
lacrimation, M;
chromodacryorrhea, M;

Dried brown material around the facial area, F.

2) 0.1 mg/L
Liver, weight, incr, M;
Lacrimation, M;
Chromodacryorrhea, M;

Dried brown material around the facial area, F;

NOAEL.

3) 0.5 mg/L
Liver, weight, incr, M;
Body weight, decr, M;
Lacrimation, M;
Chromodacryorrhea, M;

Dried brown material around the facial area, F;

LOAEL.

Conclusions:

NOAEL = 100 mg/m³ or 0.1 mg/L air.

Executive summary:

Terphenyl, hydrogenated when administered by whole-body inhalation exposure as an aerosol to 90 CD (Sprague-Dawley derived) rats (15/sex/group) for six hours per day, five days per week for thirteen weeks at target concentrations of 0, 10, 100 and 500 mg /m³ (groups I, II, III,IV). Exposure levels for Groups I-IV were determined by gas chromatographic assay (GC) of samples collected on filters. Concentration was also monitored gravimetrically for Groups II, III and IV as a secondary assay. In addition, distribution samples were taken at least three times during the study from four locations in the chamber for each group (Groups II-IV) and assayed by GC. Particle size distribution measurements were made using a Batelle cascade impactor and a TSI Model 3300/3302 Aerodynamic Particle Sizer. Detailed physical examinations were conducted once a week on all animals; in addition, once per exposure the animals were observed as a group in-chamber. Body weights were recorded pretest, weekly during the study and at termination. Blood specimens for hematology and clinical chemistry evaluations were collected from 40 animals (10/sex/group) at midterm and from the same 10 animals/sex/group after the sixty-fifth exposure(males) and sixty-fourth exposure (females). All animals (Groups I-IV) were weighed prior to sacrifice. Complete gross postmortem examinations were conducted on all animals ; selected organs were weighed and organ/body weight ratios were calculated. Histopathological evaluations were performed on selected tissues from all animals of the control and high-dose groups ( Groups I and IV). The tissues and organs with visible lesions, and masses from all animals were examined microscopically. The treated animals were exposed to cumulative mean analytical concentrations of 11, 99/98 (Male/Female) and 480 mg/m³ Terphenyl, hydrogenated, respectively. Particle size distribution measurements revealed the test atmospheres contained particles of respirable size. One Group I female and one Group II female died spontaneously during the study. The Group II female’s death was not considered treatment related. Increased incidences of chromodacryorrhea, excess lacrimation and rough coat were exhibited by all groups of treated males compared to control males. Increased incidences of dried brown material around the facial area were exhibited by all treated groups of females compared to control females. These findings were considered to be treatment related. The mean body weights were decreased approximately 8% for the Group IV males during the study compared to the control males. The differences between Group IV and control males were considered suggestive of a treatment related effect. Although some statistically significant differences were seen at study termination between clinical chemistry values for control and treated groups, values were generally within control ranges and the absence of supporting microscopic lesions or organ weight findings suggests these clinical chemistry results were insufficient to be considered toxicologically significant. The mean absolute and relative liver weights were increased for all groups of treated males compared to control males. The differences between treated and control males were statistically significant for all comparisons except for the absolute liver weights of Group II and III males. Postmortem findings, observed grossly and microscopically, either occurred in the treated and control animals with comparable incidence and severity or they occurred sporadically. These findings did not appear to be related to the test article. The NOAEL was considered to be 100 mg/m³ or 0.1 mg/L air.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

NOAEC

100 mg/m³

Study duration:

subchronic

Species:

rat

Repeated dose toxicity: inhalation - local effects

Link to relevant study records

Reference

Endpoint:

sub-chronic toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP-compliant study, available as unpublished report, well-documented, no restrictions, adequate for assessment.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 413 (Subchronic Inhalation Toxicity: 90-Day Study)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Breeding Laboratories, Inc., Wilmington, Massachusetts 01887
- Age at study initiation: 9 weeks (males) and 8 weeks (females)
- Weight at study initiation: 319 gr for males (300-339) and 192 gr for females (175-208)
- Housing: doubly housed during the first week then individually housed
- Diet (e.g. ad libitum): ad libitum (Standard laboratory diet) during acclimation period; None during exposure period
- Water (e.g. ad libitum): ad libitum during acclimation period; None during exposure period
- Acclimation period: 21/22 days (4 to 25/26 September 1984)

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21-31 °C
- Humidity (%): 24-95% (R.H.)
- Photoperiod (hrs dark / hrs light): 12 hour light/dark cycle (7am to 7 pm)

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

whole body

Vehicle:

other: unchanged (no vehicle)

Remarks on MMAD:

MMAD / GSD: Batelle cascade impactor:
MMAD (microns): 1.9, 1.8, 1.6 for groups exposed to 10, 100 ang 500 mg/m³ respectively.
GSD: 2.0, 1.8, 1.9 for groups exposed to 10, 100 ang 500 mg/m³ respectively.

TSI model:
MMAD (microns): 3.1, 2.0, 4.7 for groups exposed to 10, 100 ang 500 mg/m³ respectively.
GSD: 1.9, 1.9, 2.8 for groups exposed to 10, 100 ang 500 mg/m³ respectively.

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Chamber volume: one cubic meter
- Effective volume: 760 liters
- Air flow rate: average of 200 liters per minute (1 ppm)
- Air change rate: one complete air change every 5 minutes (average)
- Method of particle size determination: Using a Batelle cascade impactor and a TSI model 3300/3302 Aerodynamic Particle Sizer.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Exposure levels were determined by gas chromatographic assay (GC) of samples collected on filters. Concentration was also monitored gravimetrically as a secondary assay. In addition, distribution samples were taken at least three times during the study from four locations in the chamber for each group and assayed by GC.

Duration of treatment / exposure:

90 days

Frequency of treatment:

6 hours/day, 5 days/week (67 number of exposures per group/sex)

Dose / conc.:

0 mg/m³ air

Dose / conc.:

10 mg/m³ air

Remarks:

corresponding to 11.4 mg/m³ (males) and 11.3 mg/m³ (females)

Dose / conc.:

100 mg/m³ air

Remarks:

corresponding to 98.7 mg/m³ (males) and 98.4 mg/m³ (females)

Dose / conc.:

500 mg/m³ air

Remarks:

corresponding to 480 mg/m³ (males) and 479 mg/m³ (females)

No. of animals per sex per dose:

15 animals per sex per group

Control animals:

yes

Observations and examinations performed and frequency:

MORTALITY AND GROSS SIGNS OF TOXICOLOGIC OR PHARMACOLOGIC EFFECT:
- Time schedule: twice daily

DETAILED PHYSICAL OBSERVATIONS: Yes
- Time schedule: once a week

BODY WEIGHT: Yes
- Time schedule for examinations: Recorded pretest, weekly during the study and at termination.

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: pretest and at termination

HAEMATOLOGY: Yes
- Time schedule for collection of blood: at midterm and after the sixty-fifth exposure (males) and sixty-fourth exposure (females)
- Anaesthetic used for blood collection: Yes (identity): light ether anesthesia.
- Animals fasted: Yes
- How many animals: 40 animals (10/sex/group)
- Parameters checked in Table 1 were examined.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: at midterm and after the sixty-fifth exposure (males) and sixty-fourth exposure (females)
- Animals fasted: Yes
- How many animals: 40 animals (10/sex/group)
- Parameters checked in Table 2 were examined.

Sacrifice and pathology:

GROSS PATHOLOGY: Yes (see Table 3)
HISTOPATHOLOGY: Yes (see Table 4)

Clinical signs:

effects observed, treatment-related

Mortality:

mortality observed, treatment-related

Body weight and weight changes:

effects observed, treatment-related

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

no effects observed

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

not examined

Details on results:

CLINICAL SIGNS AND MORTALITY:
One Group I (control) female and one Group II (10 mg/m³) female died spontaneously during the study. Two Group II females and one Group IV (500 mg/m³) female died accidentally during blood collection. The one Group II female's spontaneous death did not appear to be treatment related.

Increased incidences of chromodacryorrhea, excess lacrimation and rough coat were exhibited by all groups of treated males compared to control males. The increased incidence of rough coat noted in the treated males did not appear to correlate with the presence of test material on the fur. Increased incidences of dried brown material around the facial area were exhibited by all treated groups of females compared to control females. These findings were considered to be treatment related.

BODY WEIGHT AND WEIGHT GAIN:
The mean body weights were decreased approximately 8% for the Group IV males during the study compared to the control males. The differences between Group IV and control males were considered suggestive of a treatment related effect. Comparisons between body weights for Group II and III (100 mg/m³) males and all groups of treated females, and the respective control animals were considered unremarkable.

OPHTHALMOSCOPIC EXAMINATION:
The following findings were noted at the terminal ophthalmology examination: proptosis and corneal necrosis (unilateral, 1 Group II male), conjunctivitis secondary to infectious disease or dental abnormality (unilateral, 1 Group IV male), retinal degeneration (bilateral, 1 Group I female) and phthisis bulbi which was secondary trauma or endophthalmitis (unilateral, 1 Group I female and 1 Group III female). These findings were not considered treatment related.

HAEMATOLOGY:
Haematology results were considered unremarkable.

CLINICAL CHEMISTRY:
The mean serum glutamic oxaloacetic transaminase and glucose levels were decreased for the Group IV females compared to the control females, and the mean total protein, albumin and calcium levels were increased for Group III and IV females compared to control females. Because the findings followed a pattern related to exposure concentration for Group III and IV females, these differences appeared to be treatment related. However, the majority of values were within historical control ranges and the nature of changes is not suggestive of an adverse effect. The absence of supporting microscopic lesions or organ weight findings in the liver, heart or other tissues suggests these clinical chemistry differences were insufficient to be considered toxicologically significant.
The mean blood urea nitrogen level was increased for Group IV males at Test Week 14 compared to control males. However, values were within historical ranges and no renal pathology was seen. Therefore, this difference is not considered to be toxicologically significant.

ORGAN WEIGHTS:
The mean absolute and relative liver weights were increased for all groups of treated males compared to control males. The differences between treated and control males were statistically significant for all comparisons except for the absolute liver weights of Group II and III males. These findings were considered treatment related. Mean absolute and relative liver weights were unremarkable in the treated females. There were no other findings in the organ weight data of the males or females which were attributed to the test material.

GROSS PATHOLOGY & HISTOPATHOLOGY (NON-NEOPLASTIC)
Postmortem findings, observed grossly and microscopically, either occurred in the treated and control animals with comparable incidence and severity or they occurred sporadically. These findings did not appear to be related to the test article.

Dose descriptor:

NOAEL

Effect level:

0.1 mg/L air

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

clinical biochemistry

clinical signs

gross pathology

haematology

mortality

ophthalmological examination

organ weights and organ / body weight ratios

Dose descriptor:

LOAEL

Effect level:

0.5 mg/L air

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

clinical biochemistry

clinical signs

gross pathology

haematology

mortality

ophthalmological examination

organ weights and organ / body weight ratios

Critical effects observed:

not specified

1) 0.01 mg/L
liver, weight, incr, M;
lacrimation, M;
chromodacryorrhea, M;

Dried brown material around the facial area, F.

2) 0.1 mg/L
Liver, weight, incr, M;
Lacrimation, M;
Chromodacryorrhea, M;

Dried brown material around the facial area, F;

NOAEL.

3) 0.5 mg/L
Liver, weight, incr, M;
Body weight, decr, M;
Lacrimation, M;
Chromodacryorrhea, M;

Dried brown material around the facial area, F;

LOAEL.

Conclusions:

NOAEL = 100 mg/m³ or 0.1 mg/L air.

Executive summary:

Terphenyl, hydrogenated when administered by whole-body inhalation exposure as an aerosol to 90 CD (Sprague-Dawley derived) rats (15/sex/group) for six hours per day, five days per week for thirteen weeks at target concentrations of 0, 10, 100 and 500 mg /m³ (groups I, II, III,IV). Exposure levels for Groups I-IV were determined by gas chromatographic assay (GC) of samples collected on filters. Concentration was also monitored gravimetrically for Groups II, III and IV as a secondary assay. In addition, distribution samples were taken at least three times during the study from four locations in the chamber for each group (Groups II-IV) and assayed by GC. Particle size distribution measurements were made using a Batelle cascade impactor and a TSI Model 3300/3302 Aerodynamic Particle Sizer. Detailed physical examinations were conducted once a week on all animals; in addition, once per exposure the animals were observed as a group in-chamber. Body weights were recorded pretest, weekly during the study and at termination. Blood specimens for hematology and clinical chemistry evaluations were collected from 40 animals (10/sex/group) at midterm and from the same 10 animals/sex/group after the sixty-fifth exposure(males) and sixty-fourth exposure (females). All animals (Groups I-IV) were weighed prior to sacrifice. Complete gross postmortem examinations were conducted on all animals ; selected organs were weighed and organ/body weight ratios were calculated. Histopathological evaluations were performed on selected tissues from all animals of the control and high-dose groups ( Groups I and IV). The tissues and organs with visible lesions, and masses from all animals were examined microscopically. The treated animals were exposed to cumulative mean analytical concentrations of 11, 99/98 (Male/Female) and 480 mg/m³ Terphenyl, hydrogenated, respectively. Particle size distribution measurements revealed the test atmospheres contained particles of respirable size. One Group I female and one Group II female died spontaneously during the study. The Group II female’s death was not considered treatment related. Increased incidences of chromodacryorrhea, excess lacrimation and rough coat were exhibited by all groups of treated males compared to control males. Increased incidences of dried brown material around the facial area were exhibited by all treated groups of females compared to control females. These findings were considered to be treatment related. The mean body weights were decreased approximately 8% for the Group IV males during the study compared to the control males. The differences between Group IV and control males were considered suggestive of a treatment related effect. Although some statistically significant differences were seen at study termination between clinical chemistry values for control and treated groups, values were generally within control ranges and the absence of supporting microscopic lesions or organ weight findings suggests these clinical chemistry results were insufficient to be considered toxicologically significant. The mean absolute and relative liver weights were increased for all groups of treated males compared to control males. The differences between treated and control males were statistically significant for all comparisons except for the absolute liver weights of Group II and III males. Postmortem findings, observed grossly and microscopically, either occurred in the treated and control animals with comparable incidence and severity or they occurred sporadically. These findings did not appear to be related to the test article. The NOAEL was considered to be 100 mg/m³ or 0.1 mg/L air.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Repeated dose toxicity: dermal - systemic effects

Link to relevant study records

Reference

Endpoint:

short-term repeated dose toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP-compliant study, available as unpublished report, well-documented, no restrictions, adequate for assessment.

Principles of method if other than guideline:

Method: other: International Research and Development Corp. method

GLP compliance:

yes

Limit test:

no

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Dutchland Laboratories, Denver, Pennsylvania
- Age at study initiation: young adult
- Weight at study initiation: mean of 2509 g (males) - 2495 g (females)
- Housing: individually housed
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 20 to 22 days prior to study initiation

ENVIRONMENTAL CONDITIONS
- Photoperiod (hrs dark / hrs light): 12 hour on/off cycle

IN-LIFE DATES: Study initiated on March 11, March 12 and March 13, 1980 and sacrificed on April 1, April 2 and April 3, 1980.

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on exposure:

TEST SITE
- Area of exposure: the back
- % coverage: approximately 30% of the body surface
- Type of wrap if used: Saran Wrapt and Elastoplast tape
- Time intervals for shavings or clipplings: The rabbits were shaved as needed during the study period to prevent the test or control articles from becoming matted in the hair and to facilitate accurate observations. Twice each week, immediately prior to test or control article administration, the dorsal skin of one-half of the rabbits in each sex group was abraded.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): the test site is washed with tepid IRDC tap water. Disposable paper towels were used to wash and dry the test site.
- Time after start of exposure: 6 hours

TEST MATERIAL
Individual doses were adjusted weekly based on the body weights obtained at the beginning of each study week.

USE OF RESTRAINERS FOR PREVENTING INGESTION: yes

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

21 days

Frequency of treatment:

6 hours/day, 5 days/week

Dose / conc.:

0 mg/kg bw/day (nominal)

Remarks:

Basis: nominal per unit body weight

Dose / conc.:

125 mg/kg bw/day (nominal)

Remarks:

Basis: nominal per unit body weight

Dose / conc.:

500 mg/kg bw/day (nominal)

Remarks:

Basis: nominal per unit body weight

Dose / conc.:

2 000 mg/kg bw/day (nominal)

Remarks:

Basis: nominal per unit body weight

No. of animals per sex per dose:

number of animals with abraded skin: 5M,5F/dose + Control article
number of animals with unabraded skin: 5M,5F/dose + Control article

Control animals:

yes

Observations and examinations performed and frequency:

MORTALITY: Yes
- Time schedule: twice daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: once daily

DERMAL IRRITATION : Yes
- Time schedule for examinations: once daily

BODY WEIGHT: Yes
- Time schedule for examinations: obtained and recorded during the pretest period and at weekly intervals during the study period.

FOOD CONSUMPTION:
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: No data

FOOD EFFICIENCY:
- Body weight gain in kg/food consumption in kg per unit time X 100 calculated as time-weighted averages from the consumption and body weight gain data: Yes

WATER CONSUMPTION: No data

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- Time schedule for collection of blood: Once during the pretest period and at 21 days of study
- Anaesthetic used for blood collection: No data
- Animals fasted: No
- How many animals: on 5 rabbits (intact and abraded) per sex per group
- Parameters checked in Table 1 were examined.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: Once during the pretest period and at 21 days of study
- Animals fasted: No
- How many animals: on 5 rabbits (intact and abraded) per sex per group
- Parameters checked in Table 2 were examined.

URINALYSIS: No

NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes (see Table 3)

Statistics:

Body weights (week 3), haematologic and biochemical parameters (Day 21) and absolute and relative organ weights (terminal sacrifices) were compared by analysis of variance (one-way classification), Bartlett’s test for homogeneity of variances and the appropriate t-test (for equal or unequal variances).

Clinical signs:

no effects observed

Dermal irritation:

effects observed, treatment-related

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

not examined

Details on results:

CLINICAL SIGNS AND MORTALITY:
A number of incidental and spontaneous signs were noted for a few rabbits in the control and test groups; including: soft stool, mucoid diarrhea, brown stained anogenital region and emaciation. Female rabbit #7792, control group, exhibited signs of mucoid diarrhea, possible anorexia and emaciation prior to death. Male rabbit #7731, 2000 mg/kg, abraded skin, exhibited possible anorexia and no stool in pan prior to death. Possible anorexia was observed in an occasional animal in the control group and in the 500 and 2000 mg/kg test groups.
Two rabbits died during the course of the study period. Female rabbit #1792 (2 mI/kg, intact skin) was found dead on Day 14 and male rabbit #1131 (2000 mg/kg, abraded skin) was found dead on Day 7.

BODY WEIGHT AND WEIGHT GAIN:
No statistically significant differences were seen in group mean body weights.

DERMAL IRRITATION:
In the control group no dermal irritation was observed. At 125, 500 and 2000 mg/kg, the majority of rabbits exhibited very slight to moderate erythema, edema, atonia, desquamation and coriaceousness. Very slight to marked fissuring was also observed for some rabbits in the three test article groups. Several animals in all test groups exhibited marked desquamation during the latter part of the study. Blanching was observed infrequently in the 125 and 2000 mg/kg test article groups. An occasional animal in the 125 and 500 mg/kg test article groups also exhibited subcutaneous hemorrhaging. No eachar or exfoliation was observed in any group.

HAEMATOLOGY:
Changes in Segmented neutrophils, Lymphocytes and Erythrocytes at 2000 mg/kg were not considered to be related to Terphenyl, hydrogenated treatment.

CLINICAL CHEMISTRY:
Changes in Globulin, Total Protein and Glucose at 500 and 2000 mg/kg were not considered to he related to Terphenyl, hydrogenated treatment.

ORGAN WEIGHTS:
No toxicologically significant test article-related weight variations (absolute or relative) were observed among animals sacrificed at study termination.

GROSS PATHOLOGY:
1. Macroscopic
Toxicologically significant compound-related gross macroscopic lesions were observed in male and female rabbits receiving 125, 500 and 2000 mg/kg. The lesions commonly observed were thickening and crust formation.
2. Microscopic
Test article-related morphologic changes on the skin application sites were observed among all male and female rabbits at all dose levels; consisting of epithlial acanthosis, epidermal hyperkeratosis and inflammatory cell infiltrates among animals sacrificed at study termination. Microabscesses were present at the 2000 mg/kg dosage level. One male animal at 2000 mg/kg dosage level that died on the study, also showed similar type of changes on the skin application site mentioned above. The distribution and relative severity of the above skin changes were generally more pronounced among male and female rabbits at the 2000 mg/kg dosage level. The changes described in tissues other than the skin application sites were regarded as spontaneous in nature, not unusual for rabbits of this age and strain and unrelated to compound application.

Dose descriptor:

NOAEL

Remarks:

(Systemic toxicity)

Effect level:

2 000 mg/kg bw/day

Sex:

male/female

Basis for effect level:

body weight and weight gain

clinical biochemistry

clinical signs

dermal irritation

haematology

mortality

organ weights and organ / body weight ratios

Critical effects observed:

not specified

Conclusions:

There was no systemic toxicity up to 2.000 mg/kg bw/day. The NOAEL for systemic toxicity is therefore 2.000 mg/kg bw/day. Skin findings were observed at all dose groups, however more pronounced at the 2.000 mg/kg bw/day.

Executive summary:

Terphenyl, hydrogenated was administered by dermal application to three groups of 10 male and 10 female New Zealand White rabbits, one-half with intact skin and one-half with abraded skin, five days per week for three consecutive weeks at dosage levels of 0, 125, 500 and 2000 mg/kg. One rabbit at the high dosage level (2000 mg/kg) was found dead on study Day 7 and one control rabbit was found dead on study Day 14. A number of incidental and spontaneous pharmacotoxic signs were noted in the control and test groups. Possible anorexia was observed in an occasional animal in the control, 500 and 2000 mg/kg groups. No statistically significant differences were seen in group mean body weights. Very slight to moderate erythema, edema, atonia, desquamation, coriaceousness and very slight marked fissuring were observed for some rabbits in all test groups. Several animals in all test groups exhibited marked desquamation during the latter part of the study. Blanching (125 and 2000 mg/kg) and subcutaneous hemorrhaging (125 and 500 mg/kg) were observed. No relevant changes were observed for haematology and clinical chemistry. No toxicologically significant test article-related weight variations (absolute or relative) were observed among animals sacrificed at study termination. At macroscopic examination, commonly observed findings were thickening and crust formation of the skin were observed at all dose levels in both sexes. Test article-related histological changes on the skin application sites were observed among all male and female rabbits at all dose levels; consisting of epithelial acanthosis, epidermal hyperkeratosis and inflammatory cell infiltrates among animals sacrificed at study termination. Microabscesses were present at the 2000 mg/kg dosage level. One male animal at 2000 mg/kg dosage level that died on the study, also showed similar type of changes on the skin application site mentioned above. The distribution and relative severity of the above skin changes were generally more pronounced among male and female rabbits at the 2000 mg/kg dosage level. The changes described in tissues other than the skin application sites were regarded as spontaneous in nature, not unusual for rabbits of this age and strain and unrelated to compound application. In conclusion, daily administration of Terphenyl, hydrogenated to the skin of rabbits for 21-days produced gross and microscopic changes at the dosaqe levels of 125, 500 and 2000 mg/kg/day. There were however no major signs of systemic toxicity; the findings are considered to be related to the dermal application of Terphenyl, hydrogenated; the distribution and severity were generally more pronounced among male and female rabbits at the 2.000 mg/kg dose level.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

2 000 mg/kg bw/day

Study duration:

subacute

Species:

rat

Repeated dose toxicity: dermal - local effects

Link to relevant study records

Reference

Endpoint:

short-term repeated dose toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP-compliant study, available as unpublished report, well-documented, no restrictions, adequate for assessment.

Principles of method if other than guideline:

Method: other: International Research and Development Corp. method

GLP compliance:

yes

Limit test:

no

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Dutchland Laboratories, Denver, Pennsylvania
- Age at study initiation: young adult
- Weight at study initiation: mean of 2509 g (males) - 2495 g (females)
- Housing: individually housed
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 20 to 22 days prior to study initiation

ENVIRONMENTAL CONDITIONS
- Photoperiod (hrs dark / hrs light): 12 hour on/off cycle

IN-LIFE DATES: Study initiated on March 11, March 12 and March 13, 1980 and sacrificed on April 1, April 2 and April 3, 1980.

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on exposure:

TEST SITE
- Area of exposure: the back
- % coverage: approximately 30% of the body surface
- Type of wrap if used: Saran Wrapt and Elastoplast tape
- Time intervals for shavings or clipplings: The rabbits were shaved as needed during the study period to prevent the test or control articles from becoming matted in the hair and to facilitate accurate observations. Twice each week, immediately prior to test or control article administration, the dorsal skin of one-half of the rabbits in each sex group was abraded.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): the test site is washed with tepid IRDC tap water. Disposable paper towels were used to wash and dry the test site.
- Time after start of exposure: 6 hours

TEST MATERIAL
Individual doses were adjusted weekly based on the body weights obtained at the beginning of each study week.

USE OF RESTRAINERS FOR PREVENTING INGESTION: yes

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

21 days

Frequency of treatment:

6 hours/day, 5 days/week

Dose / conc.:

0 mg/kg bw/day (nominal)

Remarks:

Basis: nominal per unit body weight

Dose / conc.:

125 mg/kg bw/day (nominal)

Remarks:

Basis: nominal per unit body weight

Dose / conc.:

500 mg/kg bw/day (nominal)

Remarks:

Basis: nominal per unit body weight

Dose / conc.:

2 000 mg/kg bw/day (nominal)

Remarks:

Basis: nominal per unit body weight

No. of animals per sex per dose:

number of animals with abraded skin: 5M,5F/dose + Control article
number of animals with unabraded skin: 5M,5F/dose + Control article

Control animals:

yes

Observations and examinations performed and frequency:

MORTALITY: Yes
- Time schedule: twice daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: once daily

DERMAL IRRITATION : Yes
- Time schedule for examinations: once daily

BODY WEIGHT: Yes
- Time schedule for examinations: obtained and recorded during the pretest period and at weekly intervals during the study period.

FOOD CONSUMPTION:
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: No data

FOOD EFFICIENCY:
- Body weight gain in kg/food consumption in kg per unit time X 100 calculated as time-weighted averages from the consumption and body weight gain data: Yes

WATER CONSUMPTION: No data

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- Time schedule for collection of blood: Once during the pretest period and at 21 days of study
- Anaesthetic used for blood collection: No data
- Animals fasted: No
- How many animals: on 5 rabbits (intact and abraded) per sex per group
- Parameters checked in Table 1 were examined.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: Once during the pretest period and at 21 days of study
- Animals fasted: No
- How many animals: on 5 rabbits (intact and abraded) per sex per group
- Parameters checked in Table 2 were examined.

URINALYSIS: No

NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes (see Table 3)

Statistics:

Body weights (week 3), haematologic and biochemical parameters (Day 21) and absolute and relative organ weights (terminal sacrifices) were compared by analysis of variance (one-way classification), Bartlett’s test for homogeneity of variances and the appropriate t-test (for equal or unequal variances).

Clinical signs:

no effects observed

Dermal irritation:

effects observed, treatment-related

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

not examined

Details on results:

CLINICAL SIGNS AND MORTALITY:
A number of incidental and spontaneous signs were noted for a few rabbits in the control and test groups; including: soft stool, mucoid diarrhea, brown stained anogenital region and emaciation. Female rabbit #7792, control group, exhibited signs of mucoid diarrhea, possible anorexia and emaciation prior to death. Male rabbit #7731, 2000 mg/kg, abraded skin, exhibited possible anorexia and no stool in pan prior to death. Possible anorexia was observed in an occasional animal in the control group and in the 500 and 2000 mg/kg test groups.
Two rabbits died during the course of the study period. Female rabbit #1792 (2 mI/kg, intact skin) was found dead on Day 14 and male rabbit #1131 (2000 mg/kg, abraded skin) was found dead on Day 7.

BODY WEIGHT AND WEIGHT GAIN:
No statistically significant differences were seen in group mean body weights.

DERMAL IRRITATION:
In the control group no dermal irritation was observed. At 125, 500 and 2000 mg/kg, the majority of rabbits exhibited very slight to moderate erythema, edema, atonia, desquamation and coriaceousness. Very slight to marked fissuring was also observed for some rabbits in the three test article groups. Several animals in all test groups exhibited marked desquamation during the latter part of the study. Blanching was observed infrequently in the 125 and 2000 mg/kg test article groups. An occasional animal in the 125 and 500 mg/kg test article groups also exhibited subcutaneous hemorrhaging. No eachar or exfoliation was observed in any group.

HAEMATOLOGY:
Changes in Segmented neutrophils, Lymphocytes and Erythrocytes at 2000 mg/kg were not considered to be related to Terphenyl, hydrogenated treatment.

CLINICAL CHEMISTRY:
Changes in Globulin, Total Protein and Glucose at 500 and 2000 mg/kg were not considered to he related to Terphenyl, hydrogenated treatment.

ORGAN WEIGHTS:
No toxicologically significant test article-related weight variations (absolute or relative) were observed among animals sacrificed at study termination.

GROSS PATHOLOGY:
1. Macroscopic
Toxicologically significant compound-related gross macroscopic lesions were observed in male and female rabbits receiving 125, 500 and 2000 mg/kg. The lesions commonly observed were thickening and crust formation.
2. Microscopic
Test article-related morphologic changes on the skin application sites were observed among all male and female rabbits at all dose levels; consisting of epithlial acanthosis, epidermal hyperkeratosis and inflammatory cell infiltrates among animals sacrificed at study termination. Microabscesses were present at the 2000 mg/kg dosage level. One male animal at 2000 mg/kg dosage level that died on the study, also showed similar type of changes on the skin application site mentioned above. The distribution and relative severity of the above skin changes were generally more pronounced among male and female rabbits at the 2000 mg/kg dosage level. The changes described in tissues other than the skin application sites were regarded as spontaneous in nature, not unusual for rabbits of this age and strain and unrelated to compound application.

Dose descriptor:

NOAEL

Remarks:

(Systemic toxicity)

Effect level:

2 000 mg/kg bw/day

Sex:

male/female

Basis for effect level:

body weight and weight gain

clinical biochemistry

clinical signs

dermal irritation

haematology

mortality

organ weights and organ / body weight ratios

Critical effects observed:

not specified

Conclusions:

There was no systemic toxicity up to 2.000 mg/kg bw/day. The NOAEL for systemic toxicity is therefore 2.000 mg/kg bw/day. Skin findings were observed at all dose groups, however more pronounced at the 2.000 mg/kg bw/day.

Executive summary:

Terphenyl, hydrogenated was administered by dermal application to three groups of 10 male and 10 female New Zealand White rabbits, one-half with intact skin and one-half with abraded skin, five days per week for three consecutive weeks at dosage levels of 0, 125, 500 and 2000 mg/kg. One rabbit at the high dosage level (2000 mg/kg) was found dead on study Day 7 and one control rabbit was found dead on study Day 14. A number of incidental and spontaneous pharmacotoxic signs were noted in the control and test groups. Possible anorexia was observed in an occasional animal in the control, 500 and 2000 mg/kg groups. No statistically significant differences were seen in group mean body weights. Very slight to moderate erythema, edema, atonia, desquamation, coriaceousness and very slight marked fissuring were observed for some rabbits in all test groups. Several animals in all test groups exhibited marked desquamation during the latter part of the study. Blanching (125 and 2000 mg/kg) and subcutaneous hemorrhaging (125 and 500 mg/kg) were observed. No relevant changes were observed for haematology and clinical chemistry. No toxicologically significant test article-related weight variations (absolute or relative) were observed among animals sacrificed at study termination. At macroscopic examination, commonly observed findings were thickening and crust formation of the skin were observed at all dose levels in both sexes. Test article-related histological changes on the skin application sites were observed among all male and female rabbits at all dose levels; consisting of epithelial acanthosis, epidermal hyperkeratosis and inflammatory cell infiltrates among animals sacrificed at study termination. Microabscesses were present at the 2000 mg/kg dosage level. One male animal at 2000 mg/kg dosage level that died on the study, also showed similar type of changes on the skin application site mentioned above. The distribution and relative severity of the above skin changes were generally more pronounced among male and female rabbits at the 2000 mg/kg dosage level. The changes described in tissues other than the skin application sites were regarded as spontaneous in nature, not unusual for rabbits of this age and strain and unrelated to compound application. In conclusion, daily administration of Terphenyl, hydrogenated to the skin of rabbits for 21-days produced gross and microscopic changes at the dosaqe levels of 125, 500 and 2000 mg/kg/day. There were however no major signs of systemic toxicity; the findings are considered to be related to the dermal application of Terphenyl, hydrogenated; the distribution and severity were generally more pronounced among male and female rabbits at the 2.000 mg/kg dose level.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LOAEL

1.84 mg/cm²

Study duration:

subacute

Species:

rabbit

Additional information

A key study for oral repeated dose administration was performed in rats with hydrogenated terphenyl (Monsanto, 1981); the study was conducted according to OECD 408 and GLP testing guidelines, and was considered to be reliable, adequate and relevant.  Dosing was performed during 90 days via dietary mixture to 72 Sprague-Dawley CD rats (12/sex/group) at dose levels of 50, 200 and 2000 ppm in the diet for a period of approximately 14 weeks, corresponding with nominal doses of 3, 12 and 120 mg/kg body weight/day. Control animals (12/sex/group) received a standard laboratory diet. All rats survived; the mean body weights of the high-dose females were slightly lower than control throughout the treatment-period. The mean food consumption values of high-dose males and females were slightly lower than control during the first week of the study and were unremarkable for the remainder of the treatment-period. The high-dose males exhibited slight decrease in mean hemoglobin concentration, hematocrit and erythrocyte counts and a slight increase in mean platelet count. The high-dose males exhibited slight, statistically significant elevations in mean cholesterol and albumin level. The high-dose females exhibited a slight reduction in mean glucose levels. There was an increased incidence of a spontaneously occurring renal tubular lesions in high dose males when compared to control males. The lesion incidence in low and mild dose males was similar to that observed in controls. Females were essentially free of the lesion. The etiology and toxicopathological significance of the increased incidence rate in high dose males was unclear. The NOAEL was determined at 200 ppm in the diet, corresponding to nominal 12 mg/kg body weight/day which was shown to be after analytical verification 14.8 mg/kg bw7day in males and 17.0 mg/kg bw/day in females.

A dose range finding study with hydrogenated terphenyl (also Klimisch 1) was done for two weeks at dietary concentrations of 1.000, 5.000, 10.000, 20.000 ppm, corresponding with 60, 300, 600, 1.200 mg/kg bw/day (Monsanto, 1985). Except for slight liver weight increases, there were no changes at 1.000 ppm. At 5.000 ppm, body weight decreases (F), liver weight increases and spleen weight increases (F) were observed, as well as liver gross pathological changes. At 10.000 ppm, body weight decreases, food consumption increases (M), liver weight increases and spleen weight increases (F) were observed, as well as liver gross pathological changes. At 20.000 ppm, mortality increased (M), (the cause of death was not determined), body weight decreased, food consumption increased (M), and weights were changed for kidney (decrease), liver and spleen (increases). The NOAEL was 1.000 ppm in the diet, corresponding with 60 mg/kg body weight/day.

Additional studies with hydrogenated terphenyl in rats, followed by a 4-week recovery period, were not taken into account for safety assessment (Monsanto, IBT studies 1971 & 1972) since IBT studies are considered to be unreliable unless otherwise stated (as documented in the OECD HPV manual)

There were other studies with hydrogenated terphenyl given to rats and rabbits (Monsanto) for 70 days at doses of 1.004, 4.016, 10.04 mg/kg bw/day, however systematic illness in rats and an infection in rabbits led to the conclusion that these studies are also not considered to be reliable.

Finally, the test material was also given to mice for 112 days (1 or 2 doses/week) at doses of 20 to 2.000 mg/kg bw/day (Adamson, 1973). Effects observed were kidney histopathogical findings in males at 600 (slight) and 1200 mg/kg bw/day. NOAEL was 600 mg/kg body weight/day.

 

A key study for dermal repeated dose administration was performed in rats with hydrogenated terphenyl (Monsanto, 1986) was conducted according to GLP testing guidelines, and was considered to be reliable, adequate and relevant.  Hydrotenated terphenyl was administered by dermal application to three groups of 10 male and 10 female New Zealand White rabbits, one-half with intact skin and one-half with abraded skin, five days per week for three consecutive weeks at dosage levels of 0, 125, 500 and 2000 mg/kg. One rabbit at the high dosage level (2000 mg/kg) was found dead on study Day 7 and one control rabbit was found dead on study Day 14. A number of incidental and spontaneous signs were noted in the control and test groups. Possible anorexia was observed in an occasional animal in the control, 500 and 2000 mg/kg groups. No statistically significant differences were seen in group mean body weights. Very slight to moderate erythema, edema, atonia, desquamation, coriaceousness and very slight marked fissuring were observed for some rabbits in all test groups. Several animals in all test groups exhibited marked desquamation during the latter part of the study. Blanching (125 and 2000 mg/kg) and subcutaneous hemorrhaging (125 and 500 mg/kg) were observed. No relevant changes were observed for haematology and clinical chemistry. No toxicologically significant test article-related weight variations (absolute or relative) were observed among animals sacrificed at study termination. At macroscopic examination, commonly observed findings were thickening and crust formation of the skin which were observed at all dose levels in both sexes. Test article-related histological changes on the skin application sites were observed among all male and female rabbits at all dose levels; consisting of epithelial acanthosis, epidermal hyperkeratosis and inflammatory cell infiltrates among animals sacrificed at study termination. Microabscesses were present at the 2000 mg/kg dosage level. One male animal at 2000 mg/kg dosage level that died on the study, also showed similar type of changes on the skin application site mentioned above. The distribution and relative severity of the above skin changes were generally more pronounced among male and female rabbits at the 2000 mg/kg dosage level. The changes described in tissues other than the skin application sites were regarded as spontaneous in nature, not unusual for rabbits of this age and strain and unrelated to compound application. In conclusion, daily administration of hydrogenated terphenyl to the skin of rabbits for 21-days produced gross and microscopic changes at the dosage levels of 125, 500 and 2000 mg/kg/day. There were however no major signs of systemic toxicity; the findings are considered to be related to the dermal application of hydrogenated terphenyl; the distribution and severity were generally more pronounced among male and female rabbits at the 2.000 mg/kg dose level.

Several animals in all test groups exhibited marked desquamation during the latter part of the study (Monsanto 1984). Blanching (125 and 2000 mg/kg) and subcutaneous hemorrhaging (125 and 500 mg/kg) were observed, however there was no systemic toxicity observed. Descriptor: LOAEL = 125 mg/kg; Corrected LOAEL = 125 mg/kg x 2.5 kg / 170 cm2 = 1,84 mg/cm2

 

A key study for inhalation repeated dose administration was performed in rats with hydrogenated terphenyl (Monsanto, 1986); the study was conducted according to OECD 413 and GLP testing guidelines, and was considered to be reliable, adequate and relevant. Hydrogenated terphenyl when administered by whole-body inhalation exposure as an aerosol to 90 CD (Sprague-Dawley derived) rats (15/sex/group) for six hours per day, five days per week for thirteen weeks at target concentrations of 0, 10, 100 and 500 mg /m³ (groups I, II, III,IV). One Group I female and one Group II female died spontaneously during the study. The Group II female’s death was not considered treatment related. Increased incidences of chromodacryorrhea, excess lacrimation and rough coat were exhibited by all groups of treated males compared to control males. Increased incidences of dried brown material around the facial area were exhibited by all treated groups of females compared to control females. These findings were considered to be treatment related. The mean body weights were decreased approximately 8% for the Group IV males during the study compared to the control males. The differences between Group IV and control males were considered suggestive of a treatment related effect. Although some statistically significant differences were seen at study termination between clinical chemistry values for control and treated groups, values were generally within control ranges and the absence of supporting microscopic lesions or organ weight findings suggests these clinical chemistry results were insufficient to be considered toxicologically significant. The mean absolute and relative liver weights were increased for all groups of treated males compared to control males. The differences between treated and control males were statistically significant for all comparisons except for the absolute liver weights of Group II and III males. Postmortem findings, observed grossly and microscopically, either occurred in the treated and control animals with comparable incidence and severity or they occurred sporadically. These findings did not appear to be related to the test article. The NOAEL was considered to be 100 mg/m³ or 0.1 mg/L air.

Additional inhalation studies with lower Klimisch scores (3-4) were available in various species, however these were IBT studies not taken into account for safety assessment as IBT studies are considered to be unreliable (as documented in the OECD HPV manual). 

In mice, Terphenyl, hydrogenated was exposed as an aerosol for up to 8 days at a concentration of 0.5 mg/L air, followed by a 56-day recovery period. Histopathology of the lungs showed change of mitochondria in alveolar type 2 cells, however this change was reversible 42 days after final exposure (Adamson, 1969). A 30-day pilot aerosol inhalation toxicity study in rats with hydrogenated terphenyl at target chamber concentrations 0, 10, 50 and 250 mg/m³ air showed some hypoactivity only noted in the high dose group and only during the exposure period. The NOAEL was between 0.05 and 0.025 mg/L air (Monsanto, 1979).

Repeated dose toxicity: via oral route - systemic effects (target organ) cardiovascular / hematological: spleen; digestive: liver; urogenital: kidneys

Repeated dose toxicity: inhalation - systemic effects (target organ) digestive: liver

Repeated dose toxicity: dermal - systemic effects (target organ) other: skin

Justification for classification or non-classification

Only limited changes were seen in the key and supporting repeated dose oral, dermal and inhalation toxicity studies at dose levels above the guidance values. Therefore no classification is warranted.