4-(3-phenylpropyl)pyridine

Endpoint summary

Description of key information

Generalized systemic toxicity at doses higher than the NOAEL of 30 mg/kg bw/d.

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:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test)

GLP compliance:

yes

Limit test:

no

Specific details on test material used for the study:

Sponsors identification
Description
Chemicalname
Purity
Batchnumber
Datereceived
Storageconditions
Expi「yDate
4-(3-phenylpropyl)pyridine
Appearance: Yellowliquid
Purity: 99%

Species:

rat

Strain:

Sprague-Dawley

Details on species / strain selection:

Crl:CD(Sd)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS: Crl:CD (SD) rats, male and female, 9-10 week old (initiation of dosing)
- Source: Charles River (UK) Ltd.
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: 9-10 wks
- Weight at study initiation: 333-411 g (males); 202-254 g (females)
- Fasting period before study:
- Housing: solid floor polypropylene cages with stainless steel mesh lids and softwood flake bedding. Males housed in groups; females housed in groups until after mating, then housed individually. Cages were changed weekly.
- Diet (e.g. ad libitum): Rodent 2018C Teklad Global certified diet, ad libitum
- Water (e.g. ad libitum): municipal supply, ad libitum.
- Acclimation period: 14 days

DETAILS OF FOOD AND WATER QUALITY:

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 +/- 2
- Humidity (%): 55 +/- 15
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 5 Oct. 2009 To: 18 Jan. 2010.

Route of administration:

oral: gavage

Details on route of administration:

Dosing levels used the most recent value for individual body weight, and was adjusted appropriately throughout the study.

Vehicle:

arachis oil

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:

VEHICLE
- Justification for use and choice of vehicle (if other than water): optimal solubility
- Concentration in vehicle:
- Amount of vehicle (if gavage): 4 ml/kg bw/d
- Lot/batch no. (if required):
- Purity:

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Dosing formulations were analyzed and concentrations were within 10% of target levels. Doses prepared every 2 weeks and stored at 4 C. Stability was at least 21 days. Details on analytical procedure under a separate study.

Duration of treatment / exposure:

up to 42 days (males); 47 days (females)

Frequency of treatment:

once daily for 7 days/wk

Dose / conc.:

30 mg/kg bw/day (nominal)

Dose / conc.:

100 mg/kg bw/day (nominal)

Dose / conc.:

250 mg/kg bw/day (nominal)

Remarks:

Decreased to 150.0 mg/kg bw/d on day 3 due to excessive toxicity/deaths

Dose / conc.:

150 mg/kg bw/day (nominal)

Remarks:

Recovery Group, males and females, dosed for 42 days then maintained for 14 additional days without dosing with test material. Dose was lowered from 250 mg/kg/d to 150 mg/kg/d.

No. of animals per sex per dose:

12 for main dose groups. 5 each for recovery group and female satellite groups

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale:
A dose-range finding study was performed at 50, 100 and 200 mg/kg/d for 14 days. There were no unscheduled deaths. A finding of increased salivation was evident in animals treated with 100 and 200 mg/kg/d throughout the treatment period. Males at 200 mg/kg/d showed a slight reduction in food consumption and a reduction in body weight gain from days 1-8 and from days 11-15. Females at 200 mg/kg/d showed a reduction in body weight gain from day 8 onwards. Overall cumulative body weight gain was slightly reduced throughout the treatment period for animals given 50 and 100 mg/kg/d. Animals of either sex treated with 200 mg/kg/d showed an increase in water consumption throughout the treatment period. No treatment-related macroscopic abnormalities were detected, and there were no unscheduled deaths. Doses selected were 30, 100 and 250 mg/kg bw/d.

- Rationale for animal assignment: random
- Rationale for selecting satellite groups: yes
- Post-exposure recovery period in satellite groups: yes, 14 days
- Section schedule rationale: random

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily
- Cage side observations checked in table were included.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: prior to dosing and weekly

BODY WEIGHT: Yes
- Time schedule for examinations: weekly

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption for each animal determined and mean daily diet consumption was calculated as g food/kg body weight/day: Yes, weekly
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: Yes

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 AND COMPOUND INTAKE: Yes
- Time schedule for examinations: weekly

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- Time schedule for collection of blood: non-recovery males: prior to mating, at end of treatment in 5 selected animals from each dose group; in non-recovery females: prior to mating and at end of treatment in all intermediate and high dose groups; also after the 14-day non-treatment period in all recovery animals..
- Anaesthetic used for blood collection: No
- Animals fasted: No
- How many animals: 5 selected males, all females in main group; all recovery animals.
- Parameters checked in table were examined.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: Day 14 and prior to sacrifice
- Animals fasted: No
- How many animals:
- Parameters checked in table were examined.

URINALYSIS: Yes
- Time schedule for collection of urine: non-recovery males: at end of treatment in 5 selected animals from each dose group; in all recovery males at the end of the 14-day non-treatment period.
- Metabolism cages used for collection of urine: Yes
- Animals fasted: No
- Parameters checked in table were examined.

NEUROBEHAVIOURAL EXAMINATION: Yes.
- Time schedule for examinations: in the last week of treatment for 5 non-selected males; for females, D4 post-partum.
- Dose groups that were examined: males: each dose group. females: 5 non-selected females from control and low-dose group, all surviviing females from mid and high dose group
- Battery of functions tested: sensory activity / grip strength / motor activity / other, comprising functional observational battery.

IMMUNOLOGY: Yes / No / Not specified
- Time schedule for examinations:
- How many animals:
- Dose groups that were examined:
- Parameters checked in table [No.?] were examined.

OTHER:CAGE SIDE OBSERVATIONS: Yes
- Time schedule: prior to dosing, then once daily
- Cage side observations checked in table [No.?] were included.


amined.

OTHER:

Sacrifice and pathology:

All males in the non-recovery groups were terminated on day 43; females were sacrificed on day 5 post-partum. All non-recovery animals were subjected to gross necropsy and histopathology evaluation of selected tissues. All recovery males and females were subjected to gross necropsy and histopathology evaluation of selected tissues. Euthanasia occurred via intracardiac injection with sodium pentabarbitone followed by exsanguination.

Other examinations:

Pairing of males and females (1:1) within each treatment group on day 15, and females were allowed to deliver and rear offspring to day 5 of lactation.

Statistics:

Data was assessed by linear regression analysis followed by One-way ANOVA with Levene's test for homogeneity of variances. For homogeneous variances, pariwise comparisons were made with Dunnett's test. For recovery groups, analysis was a 2-tailed t-test with Levenes' test. For unequal variances, the data was analysed with non-parametric methods: Kruskal-Wallis ANOVA with Mann-Whitney U test. Significance of probability values was set at p ≤ 0.05. Histopathology data used Chi square analysis or Kruskal-Wallis one-way non-parametric ANOVA for comparison of severity grades.

Clinical signs:

effects observed, non-treatment-related

Description (incidence and severity):

Clinical effects included increased salivation and generalised fur staining occurring in mid and high dose level animall

Mortality:

mortality observed, treatment-related

Description (incidence):

Two females treated with the high dose level were killed in extremis on Day 3
prior to the reduction of the dose level. A further two females from this treatment group
were killed in extremis on Day 40 and Day 42 following difficulties during parturition.
One female treated with 100 mg/kg/day was killed in extremis on Day 40 following
difficulties during parturition and a further female from this treatment group was killed in
extremis on Day 41 following evidence of further littering one day after the recorded
completion of littering. One female treated with 30 mg/kg/day was killed in extremis on
Day 13. The cause of death for this animal was due to inappropriate administration of
test material so not associated with treatment.

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Body weight and body weight gains were decreased at various times in male and female animals of all dose groups.

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

Males treated at the high dose level showed a reduction in food consumption and food efficiency during Week 1.

Food efficiency:

not examined

Description (incidence and severity):

not a dietary study

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

effects observed, treatment-related

Description (incidence and severity):

An increase in water consumption was evident during Week 4 and Week 5 in males, and in females during the first week, at the high and mid dose levels. An increase in water consumption was also noted during Week 6 for males treated with 100 mg/kg/day.

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Description (incidence and severity):

Females in the high dose level showed a significant reduction in erythrocyte count and haematocrit at both the Day 14.

Clinical biochemistry findings:

no effects observed

Description (incidence and severity):

Mid and high dose males: increased creatinine, albumin/globulin ratio, albumin and calcium concentrations, sustained through the recovery period. An increase in total protein was seen for males from all treatment groups on Day 14. A decrease in glucose for males from the high dose level (Day 14) amd an increase in urea was seem for males treated at the high dose level (Day 42). Males at 30 mg/kg/day showed increases in albumin at Day 14 and in albumin/globulin ratio and albumin at Day 42. Females at the high dose level showed increases in albumin, calcium concentration, cholesterol, creatinine, total protein and a statistically significant reduction in chloride concentration on Day 14. Mid dose level females showed increased albumin levels.

Urinalysis findings:

no effects observed

Behaviour (functional findings):

no effects observed

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, non-treatment-related

Description (incidence and severity):

High dose males, animals of both sexes in the mid dose group, and low dose males showed a statistically significant increase in liver weight both absolute and relative to terminal bodyweight. High and mid dose males also showed a statistically significant increase in absolute and relative kidney weight. High dose males showed a reduction in absolute adrenal weight. Recovery high dose males and females continued to show the increase in relative liver weight.

Gross pathological findings:

effects observed, treatment-related

Description (incidence and severity):

Four males treated at both the mid and high dose levels had enlarged livers and/or mottled or pale liver at necropsy. One high dose female also had pale patches on the liver. Two males in each of the mid and low dose groups had small testes and epididymides. Two females treated at the high dose level and
one in the mid dose group had pale adrenals at necropsy.

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

Males: Hepatic centrilobular hepatocyte enlargement. Both sexes: Periportal lipid-type vacuolation in liver, statistically significantly and treatment-related for high dose females and for males treated with mid and low doses (not high doses). All treated females: increased incidence of mononuclear cell foci. Thyroid: Follicular cell hypertrophy in animals of both sexes in the mid dose group, and low dose males. Adrenal gland cortical vacuolation was seen for males treated at the high and mid dose levels. Renal globular accumulations of eosinophilic material were observed in the tubular epithelium of males of all dose levels. Associated tubular basophilia was seen for males in the mid and high dose levels. There was spermatid retention in testes of high dose males.

Histopathological findings: neoplastic:

not examined

Other effects:

effects observed, treatment-related

Description (incidence and severity):

High dose females: abnormal oestrous cycle (extended or irregular oestrous cycle)

Details on results:

Treatment of 4-PPP at the given doses resulted in treatment-related effects in animals of either sex
from all treatment groups.
For male animals, clinical observation findings (ataxia, lethargy, hunched posture, piloerection,
generalised fur staining, tip toe gait, increased salivation and decreased
respiratory rate), reduced bodyweight gain, reduced food consumption, increased water
consumption, statistically significant blood chemical changes (increases in creatinine,
albumin/globulin ratio, total protein, albumin, calcium and urea and reduction in glucose),
organ weight changes (increase in liver and kidney and reduction in adrenal),
macroscopic (enlarged, mottled and pale liver, enlarged kidneys, small testes and
epididymides) and microscopic changes (spermatid retention in testes, centrilobular
hepatocyte enlargement, periportal lipid-type vacuolation in liver, thyroid follicular cell
hypertrophy, cortical vacuolation in adrenal, adipose infiltration of bone marrow and
globular accumulations of eosinophilic material and tubular basophilia in kidney) was
recorded at high dose group. Also at 100 mg/kg/day, clinical observation finding
(increased salivation), reduced bodyweight gain, increased water consumption,
statistically significant blood chemical changes (increases in creatinine, albumin/globulin
ratio, total protein, albumin and calcium), organ weight changes (increase in liver and
kidney), macroscopic (enlarged and pale liver, and small testes and epididymides) and
microscopic changes (spermatid retention in testes, centrilobular hepatocyte
enlargement, periportal lipid-type vacuolation in liver, thyroid follicular cell hypertrophy,
cortical vacuolation in adrenal and globular accumulations of eosinophilic material and
tubular basophilia in kidney) was recorded. At 30 mg/kg/day, statistically significant blood
chemical changes (increases in albumin/globulin ratio, total protein and albumin), organ
weight changes (increase in liver) and microscopic change (centrilobular hepatocyte
enlargement, periportal lipid-type vacuolation in liver, thyroid follicular cell hypertrophy
and globular accumulations of eosinophilic material in kidney) was recorded.

For female animals, mortality (killed in extremis for 4 animals in total, 2 animals at Day 3
and 2 animals following difficulties during parturition), clinical observation finding (ataxia,
lethargy, hunched posture, pilo-erection, generalised fur staining, tip toe gait, increased
salivation and decreased respiratory rate), reduction in motor activity, reduced
bodyweight gain, reduced food consumption, increased water consumption, statistically
significant haematological (reduction in erythrocyte count, haemoglobin, haematocrit and
activated partial thromboplastin time) and blood chemical changes (increases in
creatinine, albumin/globulin ratio, total protein, albumin, cholesterol, urea, calcium and
inorganic phosphorus and reduction in chloride), macroscopic (pale adrenal and pale
patch on liver) and microscopic change (centrilobular hepatocyte enlargement, periportal
lipid-type vacuolation in liver, thyroid follicular cell hypertrophy, mononuclear cell foci in
liver and cortical vacuolation in adrenal), abnormal oestrous cycle (extended or irregular
oestrous cycle), longer gestation length, reduction in pregnant animals and delivery
index, total litter losses in all animals were recorded at high dose group. At
100 mg/kg/day, mortality (killed in extremis for 2 animals following difficulties during or
after parturition), clinical observational findings (increased salivation and generalised fur
staining), reduction in motor activity, reduced bodyweight gain, reduced food
consumption, increased water consumption, statistically significant blood chemical
changes (increases in total protein, albumin, cholesterol, calcium and inorganic
phosphorus and reduction in chloride), organ weight change (increase in liver),
macroscopic (pale adrenals) and microscopic change (centrilobular hepatocyte
enlargement, thyroid follicular cell hypertrophy, mononuclear cell foci in liver and cortical
vacuolation in adrenal), and abnormal oestrous cycle (extended or irregular oestrous cycle) were recorded. At 30 mg/kg/day,
clinical observation finding (generalised fur staining), microscopic change (mononuclear
cell foci in liver) were recorded.

Key result

Dose descriptor:

NOAEL

Effect level:

30 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

clinical biochemistry

Key result

Critical effects observed:

yes

Lowest effective dose / conc.:

100 mg/kg bw/day (nominal)

System:

other: multiple

Organ:

adrenal glands

kidney

liver

testes

thyroid gland

Treatment related:

yes

Dose response relationship:

yes

Relevant for humans:

not specified

Significant toxicity was observed with repeated dose administration of the test material to CD rats, including deaths and severe clinical signs in females at the high dose of 250 mg/kg bw/d.  After 3 days, the high dose was reduced to 150 mg/kg bw/d and maintained for the remainder of the experiment.

Conclusions:

The substance was tested for repeated dose toxicity effects in male and female rats in a combined repeated dose toxicity study with reproduction/developmental toxicity screening test (OECD4 TG422). The substance was administered to CD rats in an arachis oil vehicle by oral gavage at doses of 0, 30, 100 and 150 (originally 250) mg/kg bw/d for 42 days (males) and 47 days (females). A recovery group of 5 animals, high dose only, was extended for an additional 14 days. The NOAEL for repeated dose toxicity was 30 mg/kg bwd because of significant observed toxicity, including deaths, at the mid and high doses of 100 and 150 mg/kg bw/d. The substance is not classified for specific target organ toxicity.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

NOAEL

30 mg/kg bw/day

Study duration:

subacute

Species:

rat

Quality of whole database:

adequate

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

Mode of Action Analysis / Human Relevance Framework

Not applicable

Additional information

Generalized systemic toxicity was observed after the test substance was administered at doses higher than 30 mg/kg bw/d to CD rats. Liver, kidney, thyroid and testes effects were noted, but these are consistent with species-specific toxicity responses in rats and are not relevant to human risk assessment. These include responses such as adaptive hepatocyte enlargement with lipid vacuolation, thyroid follicular cell hypertrophy, and cortical vacuolation of adrenal gland, all with regression during the recovery period.

Justification for classification or non-classification

Generalized systemic toxicity, but no specific target organ toxicity, was observed when the test substance was administered

to rats at doses higher than 30 mg/kg bw/d. The substance is not classified for repeated dose toxicity effects according to Regulation EC No. 1272/2008.