Reaction mass of 2,6-bis(1-phenylethyl)phenol and 2,4,6-tris(1-phenylethyl)phenol

Repeated dose toxicity: oral

Administrative data

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

December 1960 - June 1961

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Test procedure in accordance with US FDA standard methods with acceptable restrictions

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1961

Report date:

1961

Materials and methods

Principles of method if other than guideline:

Procedures following the principles described in the US Food and Drug Administration's publication entitled "Appraisal of the Safety of Chemicals in Foods, Drugs, and Cosmetics"

GLP compliance:

no

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Phenol, styrenated

EC Number:

262-975-0

EC Name:

Phenol, styrenated

Cas Number:

61788-44-1

IUPAC Name:

2,4-divinylphenol

Test animals

Species:

rat

Strain:

not specified

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Food and Drug Research Laboratories inbred colony
- Age at study initiation: no data
- Weight at study initiation: 60 - 100 g
- Fasting period before study: no data
- Housing: individual
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: no data


ENVIRONMENTAL CONDITIONS
- Temperature (°C): no data
- Humidity (%): no data
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): no data


IN-LIFE DATES: no data

Administration / exposure

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS: not applicable


DIET PREPARATION
- Rate of preparation of diet (frequency): weekly
- Mixing appropriate amounts with (Type of food): basal diet (Purina Laboratory Chow supplemented with vitamins)
- Storage temperature of food: no data


VEHICLE
Not applicable

Analytical verification of doses or concentrations:

not specified

Details on analytical verification of doses or concentrations:

No data

Duration of treatment / exposure:

90 days

Frequency of treatment:

Dietary administration, ad libitum

Doses / concentrations

Doses / concentrations 1

Remarks:

Doses / Concentrations:
100, 316, 1000, 3160, 10000 ppm
Basis:
nominal in diet

Doses / concentrations 2

Remarks:

Doses / Concentrations:
4, 12.6, 40, 126.4, 400 mg/kg (males)
Basis:
other: converted from nominal concentrations using standard food intake values

Doses / concentrations 3

Remarks:

Doses / Concentrations:
5, 15.8, 50, 158, 500 mg/kg (females)
Basis:
other: converted from nominal concentrations using standard food intake values

No. of animals per sex per dose:

- 30 rats/sex/treated group
- 60 rats/sex for controls

Control animals:

yes, plain diet

Details on study design:

No data

Positive control:

Not applicable

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily
- Cage side observations were not included.


DETAILED CLINICAL OBSERVATIONS: No data


BODY WEIGHT: Yes
- Time schedule for examinations: weekly (for the first 12 weeks)


FOOD CONSUMPTION AND COMPOUND INTAKE (feeding study):
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: No data
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: Yes (over 12 weeks)


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: No (efficiency of food calculation calculated as g body weight gain per 100 g of food eaten per sex and per group over 12 weeks)


WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): No data


OPHTHALMOSCOPIC EXAMINATION: No data


HAEMATOLOGY: Yes
- Time schedule for collection of blood: at 12 weeks
- Anaesthetic used for blood collection: No data
- Animals fasted: No data
- How many animals: 5 males + 5 females per dose group
- Parameters examined: hemoglobin, hematocrit, erythocyte count, coagulation and prothrombin times, total and differential leukocyte counts


CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: at 12 weeks
- Animals fasted: No data
- How many animals: 5 males + 5 females per dose group
- Parameters examined: blood glucose, urea nitrogen, cholesterol concentrations + liver cholesterol concentration


URINALYSIS: Yes
- Time schedule for collection of urine: at 12 weeks
- Metabolism cages used for collection of urine: No data
- Animals fasted: No data
- Parameters examined: not specified


NEUROBEHAVIOURAL EXAMINATION: No data


OTHER: No data

Sacrifice and pathology:

GROSS PATHOLOGY: Yes (10 control males + 10 control females, 5 males + 5 females per dose group)
ORGAN WEIGHTS: liver, kidneys, spleen, heart, adrenals, thyroid, pituitary gland
HISTOPATHOLOGY: Yes (same organs + macroscopic abnormalities) + Tissues preserved for possible microscopic examination: stomach, small intestine (3 sections), large intestine, pancreas, urinary bladder, testes, ovaries, salivary glands, lymph nodes, lungs, bone marrow (chondrocostal junction), muscle, thymus, brain, spinal cord

Other examinations:

No data

Statistics:

No data

Results and discussion

Results of examinations

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:

effects observed, treatment-related

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:

no effects observed

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:

effects observed, treatment-related

Histopathological findings: neoplastic:

not examined

Details on results:

BODY WEIGHT AND WEIGHT GAIN
Body weight gain over 12 weeks of dosing was significantly lower at 3160 and 10000 ppm than controls, as detailed in the table below.

FOOD EFFICIENCY
Total food intake over 12 weeks was unaffected, but Effective Food Utilization (calculated as g body weight gain per 100 g of food eaten) was significantly decreased at 10000 ppm compared to controls, as detailed in the table below.

ORGAN WEIGHTS
Mean absolute liver weight of males and females given 10000 ppm and females given 3160 ppm was significantly higher than that of controls, as detailed in the table below.

HISTOPATHOLOGY: NON-NEOPLASTIC
There was no histopathological correlates to increased liver weights.
Minimal focal thyroid hyperplasia was observed in 7 out of 10 rats (4 males + 3 females) given 10000 ppm, versus 2 cases in controls (one of which was diffuse).

Effect levels

Dose descriptor:

NOAEL

Effect level:

1 000 ppm

Sex:

male/female

Basis for effect level:

other: body weight gain; liver weight (females)

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

- Mean changes in body weight gain and Effective Food Utilization following 12 weeks of dosing:

	Net body weight gain over 12 weeks (g)		Effective Food Utilization (g/100 g) §
Concentration in food (ppm)	Males	Females	Males	Females
0	283	150	17.2	12.0
100	286	147	17.5	11.7
316	273	148	17.6	11.9
1000	282	141	17.5	11.0
3160	259***	140**	17.0	11.0
10000	225***	121***	16.1*	10.0**
§ Gram of body weight gain per 100 g of food eaten* p = 0.05 ** p = 0.01 *** p = 0.001

- Mean relative liver weight at necropsy:

	Males		Females
Concentration in food (ppm)	Liver weight (% body weight)	Change versus controls (%)	Liver weight (% body weight)	Change versus controls (%)
0	3.56	-	3.48	-
100	3.05	-14	4.00	+15
316	3.68	+3	3.75	+8
1000	3.61	+1	3.80	+9
3160	3.91	+10	4.50**	+29
10000	5.20***	+46	5.41***	+55
** p = 0.01 *** p = 0.001

Applicant's summary and conclusion

Conclusions:

Dietary administration of TSP/DSP to rats for 90 days resulted in significantly decreased body weight gain (at 3160 and 10000 ppm), reduced food efficiency (at 10000 ppm), increased relative liver weight (at 3160 ppm for females and 10000 ppm for both sexes) with no histopathological correlates, and minimal focal thyroid hyperplasia at 10000 ppm.
The NOAEL was therefore considered to be 1000 ppm, corresponding to approximately 40 or 50 mg/kg, for males or females, respectively.
TSP/DSP is not classified for repeat-dose toxicity according to the criteria of Annex VI Directive 67/748/EECor UN/EU GHS.

Executive summary:

In a 90-day dietary toxicity study (Food and Drug Research Laboratories study No.81351), Wingstay S (Styrenated Phenol, TSP/DSP) was administered as a dietary admixture to 30 rats/sex/dose (60/sex for controls) of unspecified strain and age, at dose levels of 0, 100, 316, 1000, 3160 and 10000 ppm, approximately equivalent to 0, 4, 12.6, 40, 126.4 and 400 mg/kg (males) or 0, 5, 15.8, 50, 158 and 500 mg/kg (females) based on standard food intake values, daily for 90 days. Examinations and measurements included mortality and clinical signs, body weight and body weight gain, food consumption and efficiency, hematology, coagulation, clinical chemistry (blood glucose, urea nitrogen and cholesterol, liver cholesterol) and urinalysis, at 12 weeks of dosing. Five rats per sex and per dose (10 for controls) were killed and necropsied at 90 days of dosing. Liver, kidneys, spleen, heart, adrenals, thyroid and pituitary gland were weighed and microscopically examined.

 

There were no relevant changes in mortality, clinical signs, food consumption, clinical pathology or urinalysis between groups including controls.

Body weight gains over 12 weeks of dosing were statistically significantly lower at 3160 and 10000 ppm than in controls. This was associated with a decrease in food efficiency at 10000 ppm, when compared to controls.

At necropsy, increases in relative liver weight were reported for males and females given 10000 ppm and females given 3160 ppm (+29% to +55% versus controls). No liver abnormalities were detected at microscopic examination.

An increased incidence of minimal focal thyroid hyperplasia was observed at 10000 ppm.

The NOAEL is considered to be 1000 ppm following 90 days of dosing, corresponding to approximately 40 or 50 mg/kg for males or females, respectively, based on statistically significant effects on body weight gain (both sexes) and on liver weight (females).

TSP/DSP is not classified for repeat-dose toxicity according to the criteria of Annex VI Directive 67/748/EECor UN/EU GHS.