Biphenyl-2-ol

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Link to relevant study records

Reference

Endpoint:

two-generation reproductive toxicity

Remarks:

based on test type (migrated information)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 416 (Two-Generation Reproduction Toxicity Study)

Version / remarks:

(1983)

Deviations:

yes

Remarks:

dose spacing >3-fold for dietary studies; P and F1 females rested for 2 and 3 weeks, respectively, before second mating (1 week recommended); no assessment of sperm parameters performed

Qualifier:

according to guideline

Guideline:

EPA OTS 798.4700 (Reproduction and Fertility Effects)

Qualifier:

according to guideline

Guideline:

EPA OPP 83-4 (Reproduction and Fertility Effects)

Version / remarks:

(1984)

Qualifier:

according to guideline

Guideline:

other: MAFF, 59 NohSan No. 4200, (1985)

GLP compliance:

yes

Specific details on test material used for the study:

- Name of test material (as cited in study report): Ortho-phenylphenol, (1,1'-Biphenyl)-2-ol
- Physical state: white solid flakes
- Stability: indefinitely in a cool environment, protected from light and moisture (not further specified)
- Storage condition of test material: at freezer conditions

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Breeders, Portage, MI, USA
- Age at study initiation: (P) 8 weeks
- Weight at study initiation: (P) Males: 279-340 g; Females: 180-229 g
- Housing: individually in stainless steel cages suspended over bedding of deotized animal cage board (DACB); during gestation and lactation females were housed individually in polycarbonate cages with Bed-O-Cobs bedding
- Diet: Purina Rodent Laboratory Chow 5001-4 Etts form, ad libitum
- Water: potable municiple water, ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18-26
- Humidity (%): 40-70
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: feed

Vehicle:

other: acetone/ corn oil mix

Details on exposure:

DIET PREPARATION
- Rate of preparation of diet (frequency): weekly
- Mixing procedure: The diet containing the test substance was prepared by disolving the appropriate amount of test substance for each dose level in acetone and corn oil. The corn oil mixture was then added to the diet, using acetone during diet preparation to rinse the equipment. Corn oil was added at 1% of the diet for all dose groups. To maintain the appropriate dose levels, the concentration of OPP in the diet was adjusted weekly during the premating period based on the group mean body weight and food consumption for each dose group. The concentration in the diet during the first week of the study was based on body weight and food consumption data collected during study week -1. During the mating periods, the males and females for each dose group received the concentration of OPP in the diet received by the females during the last week of the premating phase for the respective groups. (Note: The female concentration was used during the mating phase as the concentration in the diet was lower than for the males.) During the gestation and lactation periods the females from each dose group received diet which contained the concentration of OPP received during the last week of the premating period for the respective groups. Following completion of the F1a and F2a mating phases, the males received diet which contained the concentration of OPP received by the males during the last week of the premating period for the respective groups. As the dose during the lactation phase was not adjusted and food consumption during the lactation phase increases significantly, the dose during the lactation phase was approximately twice the dose received during the premating and gestation phases.
- Storage temperature of food: in a freezer at -23 °C

Details on mating procedure:

- M/F ratio per cage: 1/1
- Length of cohabitation: 21 days
- Proof of pregnancy: vaginal plug and/or sperm in vaginal smear referred to as Day 0 of pregnancy
- After 21 days of unsuccessful pairing females were treated as if pregnant (just in case insemination occurred but was not observed).
- After successful mating each pregnant female was caged in a plastic nesting cage.

A second mating was conducted in each generation. The F1b litter was then used to produce the F2 generation.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Stability and homogeneity were proven by liquid chromatographic analysis. OPP concentrations in rodent diet were varified for Weeks 1, 4, 8, 12, 16, 20, 24, 29, 32, 36, 40, 45, 49, 54, and 58.

Duration of treatment / exposure:

Duration of exposure before mating: 10 weeks
Duration of exposure in general: F0 parents: from study initiation until scheduled sacrifice, F1 parents: from weaning until scheduled sacrifice

Frequency of treatment:

daily

Details on study schedule:

- F1 parental animals not mated until 12 weeks after selected from the F1 litters.
- A rest period of 14 days (F1) and 20 days (F2), respectively, was initiated from the time the last respective litters were weaned.

Remarks:

Doses / Concentrations:
20, 100, and 500 mg/kg bw/day
Basis:
nominal in diet
based on % a.i.

No. of animals per sex per dose:

30

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: based on the results of a previous 2-generation study with animals of the same strain

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Twice daily (once daily during weekends and holidays)

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

BODY WEIGHT: Yes
- Time schedule for examinations: once a week

FOOD CONSUMPTION AND COMPOUND INTAKE:
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes

Oestrous cyclicity (parental animals):

Vaginal smears were taken for 3 weeks from 10 P and F1 females per dose level prior to mating. The vaginal smears were observed microscopically and classified as diestrous, proestrous, or estrous based on the cytology observed.

Sperm parameters (parental animals):

No sperm parameters were analysed.

Litter observations:

STANDARDISATION OF LITTERS
- Performed on day 4 postpartum: yes
- If yes, maximum of 8 pups/litter (4/sex/litter as nearly as possible); excess pups were killed and discarded.

PARAMETERS EXAMINED
The following parameters were examined in F1 / F2 offspring:
number and sex of pups, stillbirths, live births, postnatal mortality, presence of gross anomalies, weight gain, physical or behavioural abnormalities

GROSS EXAMINATION OF DEAD PUPS:
yes, for external and internal abnormalities; possible cause of death was determined for pups born or found dead

Postmortem examinations (parental animals):

SACRIFICE
- Male animals: All surviving animals after completion of mating phase
- Maternal animals: All surviving animals after each dam's pups were weaned or died, respectively

GROSS NECROPSY
- For females, the uterus was examined for implantation sites and the number was recorded. However, due to 2 breedings per generation, this data was not used to determine pregnancy.

HISTOPATHOLOGY / ORGAN WEIGHTS
The terminal body weights, kidney weights with the attached ureter* and gonad weights were collected from all P and F1 adults. Relative organ weights were calculated for all organs weighed.
The following organs were collected from P and F1 adults and preserved: coagulation gland, cervix, epididymides, kidneys with the urether attached (right and left kidneys were identified), pituitary gland, prostate gland, seminal vesicles, uterus, vagina, gross lesions, physical identifier (tattoo), ovaries and testes. All tissues were examined histologically with the exception of the tattoo and the skulls containing maloccuded teeth without any other accompanying morphologic lesions.

* The kidney and the ureter were weighed and examined microscopically because these tissues have been identified to be a target organ in other studies.

Postmortem examinations (offspring):

SACRIFICE
- The F1 offspring not selected as parental animals were sacrificed at 4 days of age.
- These animals and F2 animals were subjected to postmortem examinations: No

Statistics:

Statistical significance was determined at p≤0.05 for all tests with the exception of Bartlett's test, in which a probability value of p≤0.001 was used. All tests were two-tailed, except for adult pathology evaluations.
Body weight (adults and pups), weight gain, and food consumption data were analysed by analyses of variance (ANOVA) and if significant differences were shown by ANOVA, Dunnett's test was used to identify significant differences from the control group. Number of estrous cycles and estrous cycle length were analysed by the Kruskal-Wallis test. If significance was shown by Kruskal-Wallis, the Mann-Whitney U-test was used to identify statistical significances between groups. Litter size, length of gestation, viability index, live birth index, % of male pups, insemination length, and number of implantation sites were analysed by the Kruskai-Wallis test. If significance was shown by Kruskai-Wallis, the Dunnett's test was used to identify significant differences from the control group.
The mating index, fertility index, gestation index, perinatal deaths, and pup gross necropsy lesions were analysed using Chi-square test. If significant diffferences were shown by Chi-square, Fisher's exact test was used to identify significant differences from control group. A Bonferroni adjustment to the p value was used with the Fisher's exact test. Terminal body weights and organ weights were evaluated by Bartlett's test for homogeneity. If the data were homogeneous, an ANOVA was performed followed by Dunnett's t-test on parameters showing a significant effect by ANOVA. If the data were non-homogeneous, a Kruskal-Wallis ANOVA was performed followed by the Mann-Whitney U-test to identify statistical significance between groups. Gross- and histopathologic lesion frequencies for adults were analysed using the Chi-square test. If significant differences were shown by Chi-square, Fisher's exact test was used to identify significant differences from control group.

Reproductive indices:

mating index, fertility index

Offspring viability indices:

gestation index , live birth index, viability index, lactation index

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

1 high dose male (500 mg/kg bw/day) died on kidney failure; urine stain in high dose males (500 mg/kg bw/day)

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

in high dose males and females (500 mg/kg bw/day)

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

in high dose males and females (500 mg/kg bw/day)

Organ weight findings including organ / body weight ratios:

no effects observed

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

Compound-related lesions were noted in the kidney, urinary bladder, and ureter of high dose males (500 mg/kg bw/day)

Other effects:

not specified

Reproductive function: oestrous cycle:

no effects observed

Reproductive function: sperm measures:

not examined

Reproductive performance:

no effects observed

CLINICAL SIGNS AND MORTALITY (PARENTAL ANIMALS)
6 rats were sacrificed prior to scheduled sacrifice and 6 further rats died during the course of the study. However, only one death was considered compound-related: one high dose male (500 mg/kg bw/day) died of kidney failure.
The only clinical finding was a compound-related, though not statistically significant, increase in the number of P anf F1 males with urine stain. The urine staining was associated with gross and microscopic lesions in the urinary tract.

BODY WEIGHT (PARENTAL ANIMALS)
A compound-related decrease in body weights (as compared to controls) was noted for high dose males and females (500 mg/kg bw/day):
- Females (P): 5-7% below the control group (statistically significant), beginning on Day 21 of pre-mating phase
- Males (P): not statistically significant, but biologically relevant because (1) high dose group body weights began diverging from control, low- and mid dose groups on study Day 77 and terminated 5% lower than control group; (2) the weight gain for the high dose group was decreased.
Similar observations were made in the F1 generation animals.

FOOD CONSUMPTION (PARENTAL ANIMALS)
There was no treatment-related effect noted in males throughout the study period. For females, there was an increase in food consumption during lactation.

REPRODUCTIVE FUNCTION: ESTROUS CYCLE (PARENTAL ANIMALS)
There was no treatment-related effect noted throughout the study period.

REPRODUCTIVE PERFORMANCE (PARENTAL ANIMALS)
There was no treatment-related effect noted on the mating index, the fertility index, the gestation index or gestation length.

GROSS PATHOLOGY (PARENTAL ANIMALS)
No effects were observed for the P0 generation animals.

HISTOPATHOLOGY (PARENTAL ANIMALS)
- Reproductive organs: There were no compound-related changes noted in the reproductive organs.
- Other: Compound-related lesions were noted in the kidney, urinary bladder, and ureter of high dose males (debris in the renal pelvis, chronic active inflammation, increase severity of background lesions in high-dose group P and F1 males, transitional cell hyperplasia, calculi and chronic inflammation in the urinary bladder of high-dose group P and F1 males, dilation and hyperplasia of the ureter in high-dose group P and F1 males)

ORGAN WEIGHTS (PARENTAL ANIMALS)
There were no biologically relevant and compound-related changes in organ weights noted.

Dose descriptor:

NOAEL

Remarks:

toxicity

Effect level:

100 mg/kg bw/day

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

other: no adverse effects observed

Dose descriptor:

LOAEL

Remarks:

toxicity

Effect level:

500 mg/kg bw/day

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

body weight and weight gain

histopathology: non-neoplastic

Dose descriptor:

NOAEL

Remarks:

fertility

Effect level:

> 500 mg/kg bw/day

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

other: no adverse effects observed

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

urine stain in high dose males (500 mg/kg bw/day, P + F1)

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

in high dose males and females (P and F1, 500 mg/kg bw/day)

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

in high dose males and females (P and F1, 500 mg/kg bw/day)

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

effects observed, treatment-related

Description (incidence and severity):

statistically significant increased incidence of urinary bladder calculi in the high-dose group F1 males (500 mg/kg bw/day)

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

Compound-related lesions were noted in the kidney, urinary bladder, and ureter of high dose males (P and F1, 500 mg/kg bw/day)

Reproductive function: oestrous cycle:

no effects observed

Reproductive function: sperm measures:

not examined

Reproductive performance:

no effects observed

CLINICAL SIGNS AND MORTALITY (PARENTAL ANIMALS)
6 rats were sacrificed prior to scheduled sacrifice and 6 further rats died during the course of the study. However, only one death was considered compound-related: one high dose male (500 mg/kg bw/day) died of kidney failure.
The only clinical finding was a compound-related, though not statistically significant, increase in the number of P and F1 males with urine stain. The urine staining was associated with gross and microscopic lesions in the urinary tract.

BODY WEIGHT (PARENTAL ANIMALS)
A compound-related decrease in body weights (as compared to controls) was noted for high dose males and females (500 mg/kg bw/day):
- Males (F1): 9-13% lower body weights as compared to controls (statistically significant), beginning on Day 0 of premating phase and reflecting lower F1b pup body weights accompanied with reduced body weight gain during growth phase following weaning
- Females (F1): 7-12% lower body weights as compared to controls (statistically significant), beginning on Day 0 of premating phase and reflecting lower F1b pup body weights accompanied with reduced body weight gain during growth phase following weaning
The observations were made in the P0 as well in the F1 generation

FOOD CONSUMPTION (PARENTAL ANIMALS)
There was no treatment-related effect noted in males throughout the study period. For females, there was an increase in food consumption during lactation.

REPRODUCTIVE FUNCTION: ESTROUS CYCLE (PARENTAL ANIMALS)
There was no treatment-related effect noted throughout the study period.

REPRODUCTIVE PERFORMANCE (PARENTAL ANIMALS)
There was no treatment-related effect noted on the mating index, the fertility index, the gestation index or gestation length.

GROSS PATHOLOGY (PARENTAL ANIMALS)
The only gross observation that was considered to be compound-related was a statistically significant increased incidence of urinary bladder calculi in the high-dose group F1 males.

HISTOPATHOLOGY (PARENTAL ANIMALS)
- Reproductive organs: There were no compound-related changes noted in the reproductive organs.
- Other: Compound-related lesions were noted in the kidney, urinary bladder, and ureter of high dose males (debris in the renal pelvis, chronic active inflammation, increase severity of background lesions in high-dose group P and F1 males, transitional cell hyperplasia, calculi and chronic inflammation in the urinary bladder of high-dose group P and F1 males, dilation and hyperplasia of the ureter in high-dose group P and F1 males)

ORGAN WEIGHTS (PARENTAL ANIMALS)
There were no biologically relevant and compound-related changes in organ weights noted.

Dose descriptor:

NOAEL

Remarks:

toxicity

Effect level:

100 mg/kg bw/day

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

other: no adverse effects observed

Dose descriptor:

LOAEL

Remarks:

toxicity

Effect level:

500 mg/kg bw/day

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

body weight and weight gain

histopathology: non-neoplastic

Dose descriptor:

NOAEL

Remarks:

fertility

Effect level:

> 500 mg/kg bw/day

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

other: no adverse effects observed

Clinical signs:

no effects observed

Mortality / viability:

no mortality observed

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

significantly decreased in high dose pups (500 mg/kg bw/day)

Sexual maturation:

not specified

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Histopathological findings:

not examined

VIABILITY (OFFSPRING)
There were no compound-related effects on live birth index, viability index, lactation index, or perinatal deaths.

CLINICAL SIGNS (OFFSPRING)
There were no compound-related clinical signs for pups.

BODY WEIGHT (OFFSPRING)
There was a statistically significant and compound-related decrease in pup weights (as compared to controls) in the high dose group. For the F1a and F1b pups the lower weight was observed on lactation Day 21 (-12% and -10%, respectively).

GROSS PATHOLOGY (OFFSPRING)
No compound-related were observed at gross pathology.

Key result

Dose descriptor:

NOAEL

Remarks:

developmental

Generation:

F1

Effect level:

100 mg/kg bw/day

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

other: no adverse effects observed

Key result

Dose descriptor:

LOAEL

Remarks:

developmental

Generation:

F1

Effect level:

500 mg/kg bw/day

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

body weight and weight gain

Key result

Critical effects observed:

no

Clinical signs:

no effects observed

Mortality / viability:

no mortality observed

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

significantly decreased in high dose pups (500 mg/kg bw/day)

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Histopathological findings:

not examined

VIABILITY (OFFSPRING)
There were no compound-related effects on live birth index, viability index, lactation index, or perinatal deaths.

CLINICAL SIGNS (OFFSPRING)
There were no compound-related clinical signs for pups.

BODY WEIGHT (OFFSPRING)
There was a statistically significant and compound-related decrease in pup weights (as compared to controls) in the high dose group. For the F2a and F2b pups the lower weight was observed on Day 14 (-6% and -7%, respectively) and on Day 21 (-11% and -12%, respectively).

GROSS PATHOLOGY (OFFSPRING)
No compound-related were observed at gross pathology.

Key result

Dose descriptor:

NOAEL

Remarks:

developmental

Generation:

F2

Effect level:

100 mg/kg bw/day

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

other: no adverse effects observed

Key result

Dose descriptor:

LOAEL

Remarks:

developmental

Generation:

F2

Effect level:

500 mg/kg bw/day

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

body weight and weight gain

Key result

Critical effects observed:

no

Reproductive effects observed:

not specified

The following compound-related effects were found in the high-dose group:
- urine staining in P + F1 males
- decrease in bodyweight in P1 and F1 males and females
- decrease in pup bodyweights in the group
- increase in food consumption in females during lactation
The following findings were considered to be compound-related:
- one high-dose group male died from kidney failure
- urinary bladder calculi in high dose group males 
- Debris in the renal pelvis, chronic active inflammation, increase  severity of background lesions in high-dose group P and F1 males
- Transitional cell hyperplasia, calculi and chronic inflammation in the  urinary bladder of high-dose group P and f1 males
- Dilation and hyperplasia of the ureter in high-dose group P and F1 males
No compound-related effects on reproductive and litter parameters, organ  weights and clinical signs in pups were found.

Conclusions:

The test item had no effect on reproductive performance.

Effect on fertility: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

500 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Quality of whole database:

The available data comprise adequate and reliable (Klimisch score 1) studies. The database is thus sufficient to fulfil the standard information requirements set out in Annex IX, 8.7.3 of Regulation (EC) No 1907/2006.

Effect on fertility: via inhalation route

Endpoint conclusion:

no study available

Effect on fertility: via dermal route

Endpoint conclusion:

no study available

Additional information

A key study for toxicity to reproduction (fertility) in the rat was conducted with the test substance 2-phenylphenol (OPP) (Eigenberg, D. A. and Lake, S. G., 1995 and Bomhard, E. M. et al., 2002). The methods complied with the OECD Guideline 416 (1983), the EPA OTS 798.4700, the EPA OPP 83-4 (1984), and the MAFF, 59 NohSan No. 4200, (1985). CD Sprague Dawley rats received technical grade OPP (99.5-100% purity) via feed at dietary doses of 0, 20, 100 and 500 mg/kg bw/day to for two generations. The P and F1 adults were comprised of 30 rats/sex/group. The P and F1 adults received OPP in the diet throughout the entire study, beginning at eight weeks of age for the P adults and at weaning for the F1 adults. Prior to breeding, the animals received treated feed for a 10-week period (F1 pre-mating period began approx. two weeks following the weaning of the last F1b litter). P adults were mated to produce F1a and F1b litter and F1 adults (randomly selected F1b pups) were mated to produce F2a and F2b litters. During the study, adult animals were evaluated for the effect of OPP on body weight, food consumption, clinical signs, oestrus cycling, mating, fertility, gestation length, and litter size. However, there was no examination of sperm parameters conducted in this study. The offspring were evaluated for OPP-related effects on sex ratio, pup viability, body weight gain and clinical signs. Gross necropsy evaluations were performed on all adults and pups. Histopathological evaluation of reproductive organs, the pituitary, kidneys with ureter attached, urinary bladder, and gross lesions was performed on all P and F1 adults. There were no compound-related effects on reproductive performance and fertility noted in any of the dose groups. However, treatment with OPP induced signs of systemic toxicity. The following compound-related effects were found in the high-dose group (500 mg/kg bw/day): One high-dose group male died from kidney failure and urinary bladder calculi were observed in high dose group males. Urine staining in P + F1 males, decrease in bodyweight in P1 and F1 males and females, decrease in pup bodyweights in the group and increase in food consumption in females during lactation were reported. Debris in the renal pelvis, chronic active inflammation, increased severity of background lesions in high-dose group P and F1 males were further observed at mircroscopic examination, as well as transitional cell hyperplasia, calculi and chronic inflammation in the urinary bladder, and dilation and hyperplasia of the ureter of high-dose group P and F1 males. No compound-related effects on reproductive and litter parameters, organ weights and clinical signs in pups were found.

In the study by Eigenberg dated 1990, The rats received the test item in the diet at nominal dose levels of 40, 140, and 490 mg/kg bw/day nominal, corresponding to measured doses of 35, 125, and 460 mg/kg bw/day, respectively. Regarding systemic toxicity, the results of this 2-generation study are in accordance with previously published literature since they revealed the urinary tract as a target. The NOAEL regarding systemic toxicity was set at 35 mg/kg bw/day, which was the lowest substance level tested. Regarding reproduction, none of the examined parameters was altered by the treatment, thus indicating that the test item does not affect reproduction. The NOAEL regarding reproduction was set at ≥460 mg/kg bw/day, which was the highest substance level tested. Regarding offspring, treatment-related effects could be evidenced neither in the F1 nor in the F2 generation; thus for offspring the NOAEL also was set at ≥460 mg/kg bw/day.

Based on the results of the studies mentioned above and regarding toxicity to reproduction, a NOAEL of ≥500 mg/kg bw/day can be retained for fertility. Regarding systemic toxicity, the more sensitive NOAEL was provided by the earlier study as 35 mg/kg bw/day whereas the LOAEL was 125 mg/kg bw/day. In the more recent study (1995), the NOAEL was 100 mg/kg bw/day and the LOAEL was set at 500 mg/kg bw/day.

Since the effects observed in the study did not concern fertility and reproduction performance, classification for toxicity to reproduction (fertility) according to EU Directive 67/548/EEC and Regulation (EC) No 1272/2008 is not warranted.

Short description of key information:
1)- 2-generation reproductive toxicity study by Eigenberg and Lake (1995) according to OECD 416, rat, subchronic: NOAEL (fertility)≥500 mg/kg bw/day; NOAEL (toxicity)=100 mg/kg bw/day; LOAEL (toxicity)=500 mg/kg bw/day

2)- 2-generation reproductive toxicity study by Eigenberg (1990) according to OECD 416, rat, subchronic: NOAEL (fertility)≥460 mg/kg bw/day, which was the highest dose level tested; NOAEL (systemic toxicity)=35 mg/kg bw/day; LOAEL (systemic toxicity)=125 mg/kg bw/day

Justification for selection of Effect on fertility via oral route:
The selected study is the most adequate and reliable one based on the overall assessment of quality (GLP guideline study, reliability 1), and with special respect to duration and data presentation.

Justification for selection of Effect on fertility via inhalation route:
Reliable data from a 2-generation study for reproductive toxicity via the oral route are available.

Justification for selection of Effect on fertility via dermal route:
Reliable data from a 2-generation study for reproductive toxicity via the oral route are available.

Effects on developmental toxicity

Description of key information

1)- prenatal developmental toxicity study (OECD 414), rabbit, NOAEL (developmental toxicity)≥250 mg/kg bw/day; NOAEL (maternal toxicity)=100 mg/kg bw/day; LOAEL (maternal toxicity)=250 mg/kg bw/day
2)- prenatal developmental toxicity study (in principle similar to OECD 414), rat, NOAEL (maternal toxicity) =300 mg/kg bw/day; LOAEL (maternal toxicity) ≥700 mg/kg bw/day; NOAEL (foetotoxicity) ≥700 mg/kg bw/day; NOAEL (teratogenicity) =300 mg/kg bw/day
3)- prenatal developmental toxicity study, mouse, NOAEL (maternal toxicity) not identified since toxic effects including mortality occurred from the lowest test dose of 1450 mg/kg bw; NOAEL (developmental toxicity) not identified since effects occurred from the lowest test dose of 1450 mg/kg bw. Since the effects on the development occurred at high dose levels with obvious maternal toxicity, no impact on classification is expected from these data regarding toxicity to reproduction including developmental toxicity according to EU Directive 67/548/EEC and Regulation (EC) No 1272/2008.

Link to relevant study records

Reference

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1991

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Version / remarks:

(1981)

Deviations:

yes

Remarks:

treatment period ended on day 19 of gestation, food consumption was not recorded, mortality (spontaneous + sacrificed moribund) was 5 out of 24 (21%) in the highest dose group

Qualifier:

according to guideline

Guideline:

EU Method B.31 (Prenatal Developmental Toxicity Study)

Version / remarks:

(1988)

Qualifier:

according to guideline

Guideline:

EPA OPP 83-3 (Prenatal Developmental Toxicity Study)

Version / remarks:

(b) (1984)

Qualifier:

according to guideline

Guideline:

other: MAFF, 59 NohSan No. 4200 (1985)

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Hazleton Research Products, Inc., Kalamazoo, MI and Denver, PA, USA
- Age at study initiation: 9-10 months
- Weight at study initiation: 3.5-4.5 kg
- Housing: individually in cages with wire floors
- Diet: 4 oz/day (=113.4 g/day) Certified Laboratory Rabbit Chow No. 5322 (Purina Mills, Inc., St. Louis, MO) prior to study and was increased to 8 oz/day (= 226.8 g/day) to allow for the increased nutritional demands during pregnancy.
- Water: tap water (municipal water supply by the City of Midland)
- Acclimation period: at least 2 weeks

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on exposure:

VEHICLE
- Justification for use and choice of vehicle (if other than water):solubility characteristics of OPP
- Amount of vehicle (if gavage): 2 mL/kg bw

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Analyses of dosing solutions showed that the concentration of OPP ranged from 102% to 103% of the targeted concentrations, the mixing procedure produced a homogeneous solution and OPP was stable in corn oil for a minimum of 30 days.

Details on mating procedure:

- Impregnation procedure: artificial insemination (with the day of insemination considered Day 0 of gestation)

Duration of treatment / exposure:

on Gestation Days 9-17

Frequency of treatment:

daily

Duration of test:

until Day 28 of gestation

No. of animals per sex per dose:

16-24 inseminated females

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: based on the results of a probe study

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily
- Cage side observations included: signs of toxicity

BODY WEIGHT: Yes
- Time schedule for examinations: on Day 0, daily during the dosing period, and on Days 20 and 28 of gestation

POST-MORTEM EXAMINATIONS: Yes (limited gross pathologic examination)
- Sacrifice on gestation day 28
- Organs examined: liver, kidney, gravid uteri (weigths), histopathologic examination of kidneys to better define the degree of renal toxicity

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: Yes
- Number of corpora lutea: Yes
- Number and position of resorption sites: Yes
- Number of early resorptions: Yes (in apparently non-pregnant animals)
- Number and position of foetuses in utero: Yes
- Number of live and dead foetuses: Yes

Fetal examinations:

- Sex and body weights: Yes: all per litter
- External examinations: Yes: all per litter
- Skeletal examinations: Yes: all per litter
- Head examinations: Yes: all per litter (fresh examination of brain)

Statistics:

Maternal body weights, weight gains, organ weights (absolute and relative) and foetal body weights were evaluated by Bartlett's test for equality of variances. Based on the outcome of Bartlett's test, a parametric or non-parametric analysis of variance (ANOVA) was performed. If the ANOVA was significant, analysis by Dunnett's test or the Wilcoxon Rank-Sum test with Bonferoni's correction was performed. Statistical evaluation of the frequency of pre-implantation loss, resorptions and foetal alterations among litters and the foetal population was performed using a censored Wilcoxon test with Bonferroni's correction. The number of corpura lutea and implants, and litter size were evaluated using a non.parametric ANOVA folowed by the Wilcoxon Rank-Sum test with Bonferroni's correction. Pregnancy rates were analysed using the Fisher exact probability test. Foetal sex ratios were analysed using a binominal distribution test. Statistical outliers were identified using a sequential method, but were not excluded unless justified by sound scientific reasons unrelated to treatment.
Teh nomina alpha levels used were a=0.01 (Bartlett's test), a=0.10 (parametric and non-parametric ANOVA), a=0.05 two-sided with Bonferroni's correction (Wilcoxon Rank-Sum Test), a=0.05 two-sided (Dunnett's test, binominal distribution test), a=0.05 one-sided (Fisher's test, censored Wilcoxon test), and a= 0.02 two-sided (sequential outliers test).
Because numerous measurements were statistically compared in the same group of animals, the overall false positive (Type I errors) was expected to be much greater than the alpha levels would suggest. Therefore, the final interpretation of the numerical data considered the statistical analyses along with other factors such as dose-response relationship and whether the results were significant in light of other biologic or pathologic findings.

Details on maternal toxic effects:

Maternal toxic effects:yes. Remark: at 250 mg/kg bw/day effects on gastrointestinal tract and renal toxicity

Details on maternal toxic effects:
- Control group: 2 deaths (11%), (1 due to umbilical herniation and volvulus of the jejunum, 1 rabbit was euthanized after spontaneous abortion)
- 25 mg/kg bw/day: 2 deaths (13%), (1 as a result of blockage of gastrointestinal tract by a large hairball, 1 rabbit was euthanized after spontaneous abortion)
- 100 mg/kg bw/day: 1 death (6%), (caused by gavage error)
- 250 mg/kg bw/day: 5 deaths (21%), (4 deaths considered treatment-related, 1 rabbit was euthanized after spontaneous abortion), increased incidence of blood found in the urine and faeces, decreased amount of faeces, decreased activity, soiling, treatment-related effects within the gastrointestinal tract (ulceration and haemorrhage of the gastric mucosa, haemolysed blood within intestinal tract and decreased content and increased fluidity of ingesta), treatment-related effects on the kidneys were found in 10/24 rabbits (the kidneys had focal to multifocal tubular degeneration, slight to moderate in degree, accompanied by inflammation that was focal to multifocal and slight in degree)

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Basis for effect level:

other: maternal toxicity

Dose descriptor:

LOAEL

Effect level:

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

Based on:

test mat.

Basis for effect level:

other: maternal toxicity

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Dose descriptor:

NOAEL

Effect level:

>= 250 mg/kg bw/day (actual dose received)

Based on:

test mat.

Basis for effect level:

other: teratogenicity

Abnormalities:

not specified

Developmental effects observed:

not specified

Conclusions:

The test substance had no effect on intrauterine development.

Effect on developmental toxicity: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

250 mg/kg bw/day

Study duration:

subacute

Species:

rabbit

Quality of whole database:

The available data comprise adequate and reliable (Klimisch score 1 and 2) studies for 3 different species, one non-rodent (rabbit) and two rodents (rat and mouse). The database is thus sufficient to fulfil the standard information requirements set out in Annex IX, 8.7.2 of Regulation (EC) No 1907/2006.

Effect on developmental toxicity: via inhalation route

Endpoint conclusion:

no study available

Effect on developmental toxicity: via dermal route

Endpoint conclusion:

no study available

Additional information

A key study for prenatal developmental toxicity/teratogenicity in the rabbit was conducted with the test substance 2-phenylphenol (OPP) (Zablotny, C. L., 1991a/b and Bomhard, E.M. et al., 2002). The methods complied with the OECD Guideline 414 (1981), the EU Method B.31 (1988), the EPA OPP 83-3 (1984), and the MAFF, 59 NohSan No. 4200, (1985). Groups of 16-24 artificially inseminated adult female New Zealand White rabbits were administered OPP in corn oil via oral gavage on Days 7-19 of gestation at targeted dose levels of 25, 100 or 250 mg/kg bw/day, while concurrent control animals received the vehicle only. In-life parameters evaluated included clinical observations, body weight and body weight gain. On Day 28 of gestation, all surviving rabbits were euthanized prior to necropsy. Liver, kidney and gravid uterine weights, and the number of implantations, resorptions, corpora lutea and live/dead foetuses were recorded at necropsy. All foetuses were removed from the uterus, weighed, sexed and examined for external, visceral and skeletal alterations. The kidneys from all rabbits were examined microscopically. Oral administration of OPP to inseminated females rabbits resulted in maternal toxicity at the 250 mg/kg/day dose level as evidenced by treatment-related increased mortality (13%), gross pathological alterations (ulceration and haemorrhage of the gastric mucosa, haemolysed blood in the intestinal tract and decreased ingesta) and histopathologic alterations (renal tubular degeneration and inflammation). No significant maternal effects were observed at 25 or 100 mg/kg/day of OPP and no adverse embryonal/foetal effects were observed at any dose level tested.

Based on the results of this study, a NOAEL of ≥250 mg/kg bw/day can be deduced for developmental toxicity. Whereas an increased incidence of litters with resorptions was noted, other parameters were without findings (EFSA 2008). There is evidence that the increase in the percentage of litters with resorptions was mainly the result of the resorptions in the high-dose group being distributed across more litters, whereas the control group resorptions tended to be concentrated in fewer litters. Using the best overall indicator of resorption rate (percent post-implantation loss), the data from the OPP rabbit developmental toxicity study show no treatment-related increase in fetal resorption. In line with assessments in the original study report, the most recent assessment by the performing laboratory (Zablotny et al., (1991), ortho-Phenylphenol (OPP): Gavage Teratology Probe Study in New Zealand White Rabbits with Report Amendment no. 1, dated 2015) and by e.g. EFSA, the NOAEL for developmental toxicity for the rabbit is 250 mg/kg bw/day.

For maternal toxicity, the NOAEL is =100 mg/kg bw/day and the LOAEL is =250 mg/kg bw/day.

Regarding rodent species, a study was performed 1978 by John and coworkers. In this study, rats were treated by gavage with the test item in cotton seed oil during gestation at dose levels of 100, 300 and 700 mg/kg bw/day. Regarding maternal toxicity, since statistically significantly impaired body weight gain and increased liver weight were noticed at 700 mg/kg bw/day, the NOAEL was set at 300 mg/kg bw/day. Regarding foetotoxicity, since no treatment-related effects could be evidenced, the NOAEL was set at ≥700 mg/kg bw/day. Regarding teratogenicity, based on the increased incidence of skeletal variations noticed at ≥700 mg/kg bw/day(delayed ossification of sternebrae, occurrence of a foramen in the skull bones, occurrence of bone island), the NOAEL was set at 300 mg/kgbw/day.

A further rodent species was considered. In the study performed by Ogata et al. (1978) pregnant mice were treated by gavage with the test item in olive oil during gestation at dose levels of 1450, 1740 and 2100 mg/kg bw/day. Regarding maternal toxicity, since mortality and increase in liver weight were reported from the lowest tested dose level of 1450 mg/kg bw/day, the LOAEL was set at 1450 mg/kg bw/day; the NOAEL was not identified. Regarding developmental toxicity, for all dose levels, reduced foetal body weights with clear dose-dependency for males and reduced number of live foetuses, were reported; thus the NOAEL was not identified since the lowest dose level of 1450 mg/kg bw/day was the LOAEL. Shrinking and fissures of sternal nuclei occurred significantly more often at 1740 and 2100 mg/kg bw/day as compared to control and showed dose-dependency.It has to be noticed that obvious retardation in ossification in a significant manner only was reported as evident at 2100 mg/kg bw/day.

Since the effects on the development occurred at high dose levels with obvious maternal toxicity, classification regarding toxicity to reproduction including developmental toxicity according to EU Directive 67/548/EEC and Regulation (EC) No 1272/2008 is not warranted.

Justification for selection of Effect on developmental toxicity: via oral route:
The selected study is the most adequate and reliable one based on the overall assessment of quality (GLP guideline study, reliability 1), and with special respect to duration and data presentation.

Justification for selection of Effect on developmental toxicity: via inhalation route:
Reliable data from a prenatal developmental toxicity study via the oral route are available.

Justification for selection of Effect on developmental toxicity: via dermal route:
Reliable data from a prenatal developmental toxicity study via the oral route are available.

Justification for classification or non-classification

Based on the available data for the registered substance, 2-phenylphenol does not meet the criteria to be classified for toxicity to reproduction according to EU Directive 67/548/EEC and Regulation (EC) No 1272/2008.