1,2-Benzenedicarboxylic acid, di-C16-18-alkyl esters

Endpoint summary

Description of key information

Read Across substance 1,2-Benzenedicarboxylic acid, mixed cetyl and stearyl esters (CAS No. 68442-70-6): 
- subchronic (90 day) NOAEL of 68 mg/kg bw/d and 75 mg/kg bw/d was found for male and female rats
- subchronic (90 day) LOAEL of 683 mg/kg bw/d and 772 mg/kg bw/d was found for male and female rats

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:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

21 May 1971 - 06 Jan 1972

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Comparable to guideline study with acceptable restrictions (no rationale for dose selection given (middle dose level is 1/10 of highest dose level))

Qualifier:

equivalent or similar to guideline

Guideline:

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

Deviations:

yes

Remarks:

: lack of details on test substance; as animals were housed in groups of 5 per cage the calculation of compound intake was not individually, but calculated as mean values from each cage; No rationale for dose selection given (middle dose level is 1/10 of

GLP compliance:

no

Limit test:

no

Species:

rat

Strain:

other: CFY strain

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Carworth Europe, Alconbury, Huntingdon
- Housing: 5 per cage with wire-mesh floor.
- Diet (ad libitum): Spiller's Laboratory Small Animals Diet
- Acclimation period: 6 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 ± 2
- Humidity (%): 50 ± 5

IN-LIFE DATES: From: May, 21st, 1971 continued for 13 weeks.

Route of administration:

oral: feed

Vehicle:

corn oil

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:
The test substance was dispersed in corn-oil heated to 40ºC, and then incorporated into the diet.

DIET PREPARATION
A premix containing 20000 ppm and 4 % corn oil was prepared each week, and from this various dietary concentrations were obtained by direct dilution with further quantities of diet.
Corn oil was added so that all diets, including control diet, contained 2% corn oil. Homogeneity was achieved by mixing for 10 minutes in a rotary double-cone blender. The diets were then stored until use in heatsealed, opaque polythene bags.

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

13 weeks

Frequency of treatment:

continuously with diet

Remarks:

Doses / Concentrations:
0, 500, 1000 and 10000 ppm
Basis:
nominal in diet

Remarks:

Doses / Concentrations:
0, 34, 68 and 683 mg/kg bw/day
Basis:
other: group mean intake (males) as calculated from group mean bodyweight and food consumption

Remarks:

Doses / Concentrations:
0, 39, 75 and 772 mg/kg bw/day
Basis:
other: group mean intake (females) as calculated from group mean bodyweight and food consumption

No. of animals per sex per dose:

10

Control animals:

yes, concurrent vehicle

Positive control:

No

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes

DETAILED CLINICAL OBSERVATIONS: Yes

BODY WEIGHT: Yes
- Time schedule for examinations: weekly

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
The quantity of food consumed by each cage (not by each animal) was recorded weekly.

FOOD EFFICIENCY:
The efficiency with which food was utilized was assessed by calculation of mean food conversion ratios (FCR values) during the period of most rapid growth, the ratio representing the weight of food consumed per unit gain in bodyweight.


WATER CONSUMPTION was assessed by inspection of the water bottles. Regular measurement of water intake was not introduced since there was no evidence of a treatment-related effect.

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: Before treatment, 6 and 12 weeks after treatment commenced.
- Dose groups that were examined: Animals of the vehicle control and highest dose groups.

HAEMATOLOGY: Yes
- Time schedule for collection of blood: at weeks 4, 8 and 12 from 10 male and 10 female animals from control and highest dose groups.
After 12 weeks, also 10 males from th 1000 ppm - group were analyzed for red cell parameters.
- Anaesthetic used for blood collection: No data
- Animals fasted: No data
- Parameters checked: PCV, Hb, RBC, MCV, MCHC, PCV, Differential count,

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: at weeks 4 and 12 from 5 male and 5 female animals of the control and highest dose group.
After 12 weeks additional animals from the 1000 ppm group were analyzed for AP and GPT. After 13 weeks, males of the 1000 ppm group were examined for serum proteins.
- Animals fasted: No data
- Parameters checked: Urea, Glucose, Total serum proteins, AP, GPT, GOT, Sodium, Potassium

URINALYSIS: Yes
- Time schedule for collection of urine: weeks 4, 8 and 12 from 5 male and 5 female animals of control and highest dose groups.
- Metabolism cages used for collection of urine: No data
- Animals fasted: No data
- Parameters checked: pH, specific gravity, protein, reducing substances, glucose, ketones, bile pigments, urobilin, blood pigments, urine sediment


NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
HISTOPATHOLOGY: Yes, adrenals, brain, colon, duodenum, eyes, heart, ileum, kidneys, liver, lungs, lymph nodes, ovaries, pancreas, pituitary, spleen, stomach, testes, thymus, thyroids, urinary bladder, uterus of animals of control and highest dose groups. Additionally pancreas of rats from the 1000 ppm group were analyzed.

Other examinations:

ORGAN WEIGHTS of adrenals, brain, heart, kidneys, liver, ovaries, pituitary, spleen, testes, thyroids, uterus.
For inter-group comparison, relative organ weights were calculated as percentages of bodyweight.

Statistics:

Student's t-test

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

two male rats of the highest dose died

Mortality:

mortality observed, treatment-related

Description (incidence):

two male rats of the highest dose died

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

decreased body weight gain in the highest dose group

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

The overall food intake of males of the highest dose group was slightly less than that of the controls.

Food efficiency:

effects observed, treatment-related

Description (incidence and severity):

at highest dose

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

not examined

Ophthalmological findings:

effects observed, treatment-related

Description (incidence and severity):

in one male of the highest dose group

Haematological findings:

effects observed, treatment-related

Description (incidence and severity):

non-adverse effects

Clinical biochemistry findings:

effects observed, treatment-related

Description (incidence and severity):

Increased levels of serum AP in both sexes of the highest dose group.

Urinalysis findings:

no effects observed

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Description (incidence and severity):

slightly increased thyroid weights in males of the highest dose group

Gross pathological findings:

effects observed, treatment-related

Description (incidence and severity):

internal haemorrhages at highest dose males

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

Haemorrhage and associated chronic inflammatory reaction in the pancreas and areas of fat, throughout the body in male rats of the highest dose group.

Histopathological findings: neoplastic:

no effects observed

Details on results:

CLINICAL SIGNS AND MORTALITY
At 10000 ppm two deaths were observed among male rats.
Between weeks 6 and 10 only, slight pallor of the extremities was noted in several male rats of the highest dose group.
No other reaction to treatment was observed.

BODY WEIGHT AND WEIGHT GAIN
At 10000 ppm slight depression in rate of bodyweight gain in males and to a lesser extent in females was observed. No other significant differences were observed between control and treated group.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study)
The overall food intake of males of the highest dose group was slightly less than that of the controls. No other significant differences between control and treated groups were observed.

FOOD EFFICIENCY
Slightly decreased efficiency was seen in rats receiving 10000 ppm during the first week. This did not, however, affect the overall performance, this being comparable with that of the controls.
No decrease in efficiency was observed in the remaining treated groups.

WATER CONSUMPTION
no effects

OPHTHALMOSCOPIC EXAMINATION
In one male rat of the highest dose group extensive haemorrhage was seen in both eyes in the posterior chamber. This change was considered in relation to the changes seen during autopsy.

HAEMATOLOGY
no adverse effects were detected.

CLINICAL CHEMISTRY
Serum AP levels were abnormally high in both males and females of the highest dose group during weeks 4 and 12. Extension of the investigation to rats receiving 1000 ppm during week 12 revealed a normal value, although it was noted that the value in a single male rat was abnormally high.
The mean levels of GPT were also higher in males of the highest dose group compared to controls, but the individual values were well within the normal range, as also were the slightly depressed serum protein concentrations found in these animals during week 12. Animals of the 1000 ppm group showed values comparable to controls.
The only adverse reaction was considered to be the elevated serum AP levels in male and female rats receiving 10000 ppm in the diet.

URINALYSIS
no effects

ORGAN WEIGHTS
Slightly increased thyroid weights in males of the highest dose group.
Thyroids of male animals of the highest dose group were statistically significantly different from the control value.

GROSS PATHOLOGY
Internal haemorrhage in both male animals of the highest dose group, which died during the study period.
Change compatible with the occurence of haemorrhage were seen in all but one of the male rats that had received the highest dose in the diet.

HISTOPATHOLOGY: NON-NEOPLASTIC
Haemorrhage and associated chronic inflammatory reaction in the pancreas and in areas of fat throughout the body in male rats of the highest dose group. No other treatment-related histopathological changes were found.

Dose descriptor:

NOAEL

Effect level:

1 000 ppm

Based on:

test mat.

Remarks:

equivalent to approx. 68 mg/kg bw/d

Sex:

male

Basis for effect level:

other: No abnormalities based on clinical signs; mortality; body weight; food consumption; food efficiency; ophthalmoscopic examination; haematology; clinical chemistry; urinalysis; gross pathology; organ weights; histopathology;

Dose descriptor:

NOAEL

Effect level:

1 000 ppm

Based on:

test mat.

Remarks:

equivalent to approx. 75 mg/kg bw/d

Sex:

female

Basis for effect level:

other: No abnormalities based on clinical signs; mortality; body weight; food consumption; food efficiency; ophthalmoscopic examination; haematology; clinical chemistry; urinalysis; gross pathology; organ weights; histopathology;

Dose descriptor:

LOAEL

Effect level:

10 000 ppm

Based on:

test mat.

Remarks:

equivalent to approx. 683 mg/kg bw/d

Sex:

male

Basis for effect level:

other: see 'Remark'

Dose descriptor:

LOAEL

Effect level:

10 000 ppm

Based on:

test mat.

Remarks:

equivalent to approx. 772 mg/kg bw/d

Sex:

female

Basis for effect level:

other: Based on increased levels of serum AP

Critical effects observed:

not specified

Blood chemistry - group mean values

Group	Week No.	Urea mg%	Total Glucose mg%	SAP KA units	GPT SF units	GOT SF units	Electrolytes, mEq/l
							Na+	K+
male control animals	4	32	113	89	39	159	142	4.7
male 10000 ppm	4	37	112	140**	51**	119	144	5.0
female control animals	4	43	128	86	34	148	141	4.3
female 10000 ppm	4	38	122	116*	37	136	139	4.5
male control animals	12	40	124	59	32	121	143	5.1
male 1000 ppm	12	-	-	63	36	-	-	-
male 10000 ppm	12	42	128	98**	54***	96*	144	4.5
female control animals	12	51	121	54	45	128	142	4.8
female 1000 ppm	12	-	-	52	39	-	-	-
female 10000 ppm	12	41	121	93***	48	128	143	5.2

 

   *P < 0.05 (when compared with control value)

  **P < 0.01 (when compared with control value)

***P < 0.001 (when compared with control value)

 

Dietary administration at 500 and 1000 ppm was without overt adverse effects in all treated animals.

 

Conclusions:

It can be assumed, that the subchronic NOAEL for the test substance could have been higher than the values identified in this study - under the aspect, that the middle dose level was only one tenth of the highest dose level.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

NOAEL

68 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Quality of whole database:

The available information comprises adequate, reliable (Klimisch score 2) and consistent studies from a reference substance with similar structure and intrinsic properties. Read-across is justified based on structural similarity between the source and target substance.

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Justification for grouping of substances and read-across

There are only limited data available on the repeated dose toxicity of 1,2 benzenedicarboxylic acid, di-C16-C18-alkyl esters (CAS 90193-76-3). In order to fulfil the standard information requirements set out in Annex VII and VIII, 8.4, in accordance with Annex XI, 1.5, of Regulation (EC) No 1907/2006, read-across from structurally related substances was conducted.

In accordance with Article 13 (1) of Regulation (EC) No 1907/2006, "information on intrinsic properties of substances may be generated by means other than tests, provided that the conditions set out in Annex XI are met.” In particular for human toxicity, information shall be generated whenever possible by means other than vertebrate animal tests, which includes the use of information from structurally related substances (grouping or read-across).

Having regard to the general rules for grouping of substances and read-across approach laid down in Annex XI, Item 1.5, of Regulation (EC) No 1907/2006 whereby substances may be predicted as similar provided that their physicochemical, toxicological and ecotoxicological properties are likely to be similar or follow a regular pattern as a result of structural similarity.

Overview of repeated dose toxicity

CAS	Repeated dose toxicity oral	Repeated dose toxicity inhalation	Repeated dose toxicity dermal
90193-76-3 (a)	RA: CAS 68442-70-6	--	--
68442-70-6 (b)	Subchronic: NOAEL of 68 mg/kg bw/day and 75 mg/kg bw/day for male and female rats	--	--

(a) The substance subject to registration is indicated in bold font.

(b) Reference (read-across) substances are indicated in normal font. Lack of data for a given endpoint is indicated by “--“.

The above mentioned substance is considered to be similar on the basis of the structural similar properties and/or activities. The available endpoint information is used to predict the same endpoints for 1,2 benzenedicarboxylic acid, di-C16-C18-alkyl esters (CAS 90193-76-3). A detailed analogue approach justification is provided in the technical dossier (see IUCLID Section 13).

Discussion

CAS 90193-76-3

A 90 day oral feeding study with 1,2-Benzenedicarboxylic acid, mixed cetyl and stearyl esters (CAS No. 68442-70-6) was performed equivalent to OECD Guideline 408 in male and female CFY rats (Rivett, 1972). The test substance was mixed at concentrations of 0, 500, 1,000 and 10,000 ppm to the diet and groups of 10 animals per sex were fed ad libitum for 13 weeks. The group mean intakes as calculated from group mean bodyweight and food consumption were 0, 34, 68 and 683 mg/kg bw/day for male and 0, 39, 75 and 772 mg/kg bw/day for female rats.

At the highest dose the following abnormalities were observed: two deaths among male rats, slight depression of body weight gain in males and females, marginally reduced food consumption in males, increased serum AP levels in males and females, changes consistent with internal haemorrhage at terminal autopsy in males, slightly increased thyroid weights in males, haemorrhage and associated chronic inflammatory reaction in the pancreas and areas of fat throughout the body in males. Treatment at 500 and 1000 ppm were without overt adverse effects.

Thus, the subchronic NOAEL was set to be 68 mg/kg bw/day for male and 75 mg/kg bw/day for female and the LOAEL was set to be 683 mg/kg bw/day for male and 772 mg/kg bw/day for female rats. It can be assumed, that the subchronic NOAEL for the test substance could have been higher than the values identified in this study - under the aspect, that the middle dose level was only one tenth of the highest dose level.

 

Conclusions for repeated dose oral toxicity

There are no data available on repeated dose toxicity of 1,2 benzenedicarboxylic acid, di-C16-C18-alkyl esters (CAS 90193-76-3). However, the tested read across substance 1,2-Benzenedicarboxylic acid, mixed cetyl and stearyl esters is very similar to 1,2 benzenedicarboxylic acid, di-C16-C18-alkyl esters and has identical molecular weight. Based on these results, the NOAEL was established at 68 and 75 mg/kg bw/day for male and female rats and the LOAEL was etablished at 683 and 772 mg/kg bw/day for males and female rats.

Justification for selection of repeated dose toxicity via oral route - systemic effects endpoint:
Hazard assessment is conducted by means of read-across from structural analogues. The selected study is the most adequate and reliable study based on the identified similarities in structure and intrinsic properties between source and target substances and overall assessment of quality, duration and dose descriptor level (refer to the endpoint discussion for further details).

Justification for classification or non-classification

The available data on repeated dose toxicity do not meet the classification criteria according to Regulation (EC) 1272/2008 or Directive 67/548/EEC, and are therefore conclusive but not sufficient for classification.

.