Alcohols, C16-18 and C18-unsatd., ethoxylated

Endpoint summary

Key value for chemical safety assessment

Toxic effect type:

dose-dependent

Effects on fertility

Description of key information

Oral (rat, m/f, OECD 422): NOAEL (reproduction) = 1000 mg/kg bw/day

Oral (rat, m/f, OECD 422): NOAEL (systemic toxicity) = 1000 mg/kg bw/day

Oral (rat, m/f, OECD 422): NOAEL (local toxicity) = 1000 mg/kg bw/day

 

Read-across based on grouping of substances (category approach) considering all the available data on reproductive toxicity in the AE category, in a Weight-of-Evidence approach.

Link to relevant study records

Reference

Reference 1

Endpoint:

screening for reproductive / developmental toxicity

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Justification for type of information:

Please refer to the category justification provided in the category object.

Reason / purpose for cross-reference:

read-across source

Key result

Dose descriptor:

NOAEL

Effect level:

>= 1 000 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No toxicologically relevant effects observed

Key result

Critical effects observed:

no

Key result

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

>= 1 000 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No toxicologically relevant effects observed

Key result

Critical effects observed:

no

Key result

Reproductive effects observed:

no

For a detailed assessment of the reproductive / developmental toxicity of the Alcohol Ethoxylates (AE) category, please refer to the category justification attached to the category object.

Conclusions:

Applying read-across based on grouping of substances (category approach), no toxicologically relevant effects in relation to reproductive / developmental toxicity and a NOAEL for reproductive toxicity ≥ 1000 mg/kg bw/day are predicted for the registered substance.

Executive summary:

The available data on reproductive / developmental toxicity in the 'linear' subgroup of the Alcohol Ethoxylates (AE) category indicate no toxicologically relevant effects for the registered substance. As explained in the category justification, the differences in molecular structure and composition between the registered substance and the members of the AE category are unlikely to lead to differences with respect to reproductive / developmental toxicity.

Reference 2

Endpoint:

extended one-generation reproductive toxicity - basic test design (Cohorts 1A, and 1B without extension)

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Justification for type of information:

Please refer to the category justification provided in the category object.

Key result

Dose descriptor:

NOAEL

Effect level:

>= 1 000 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No toxicologically relevant effects observed

Key result

Critical effects observed:

no

Key result

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

>= 1 000 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No toxicologically relevant effects observed

Key result

Critical effects observed:

no

Key result

Reproductive effects observed:

no

For a detailed assessment of the reproductive / developmental toxicity of the Alcohol Ethoxylates (AE) category, please refer to the category justification attached to the category object.

Conclusions:

Applying read-across based on grouping of substances (category approach), no toxicologically relevant effects in relation to reproductive / developmental toxicity and a NOAEL for reproductive toxicity ≥ 1000 mg/kg bw/day are predicted for the registered substance.

Executive summary:

The available data on reproductive / developmental toxicity in the 'linear' subgroup of the Alcohol Ethoxylates (AE) category indicate no toxicologically relevant effects for the registered substance. As explained in the category justification, the differences in molecular structure and composition between the registered substance and the members of the AE category are unlikely to lead to differences with respect to reproductive / developmental toxicity.

Effect on fertility: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

1 000 mg/kg bw/day

Study duration:

subacute

Species:

rat

Quality of whole database:

The available information comprises adequate and reliable (Klimisch score 1) studies from various source substances in the Alcohol Ethoxylates (AE) category with similar structures and intrinsic properties. Read-across is justified based on common toxicokinetic behaviour and consistent trends in environmental fate, ecotoxicological and toxicological properties of the category member substances. The data pool of the AE category is thus sufficient to fulfil the standard information requirements set out in Annexes VIII - X, Section 8.7, in accordance with Annex XI, Section 1.5, of the REACH 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

No data on toxicity to reproduction are available for alcohols, C16-18 and C18 unsatd., ethoxylated (CAS No. 68920-66-1, EC No. 500-236-9). In order to assess the potential for toxicity to reproduction, studies in the database of the Alcohol Ethoxylates (AE) category are considered in a read-across approach. Studies investigating toxicity to reproduction are available for the following AE substances (Table 1):

Table 1

CAS No.	EC No.	Substance	Screening study (OECD 422)
			NOAEL reproduction/ fertility [mg/kg bw/day]	NOAEL systemic [mg/kg bw/day]
Linear subgroup
26183-52-8	500-046-6	Decan-1-ol, ethoxylated	≥ 950	≥ 950
68439-50-9	500-213-3	Alcohols, C12-14, ethoxylated	≥ 1000	≥ 1000
9004-95-9	939-518-5	Hexadecan-1-ol, ethoxylated	≥ 1000	≥ 1000
68439-49-6	939-518-5	Alcohols, C16-18 (even numbered), ethoxylated, < 2.5 EO	≥ 1000	≥ 1000
9004-98-2	500-016-2	(Z)-9-Octadecen-1-ol ethoxylated	≥ 1000	≥ 1000 (local: 300)
Mixed branched & linear subgroup
160901-09-7	500-446-0	Alcohols, C9-11, branched and linear, ethoxylated	300	300
160901-19-9	500-457-0	Alcohols, C12-13, branched and linear, ethoxylated	≥ 1000	≥ 1000
106232-83-1	500-294-5	Alcohols, C12-15, branched and linear, ethoxylated	≥ 1000	≥ 1000

 

Evaluation of toxicity to reproduction as observed in available studies

The database for reproductive and developmental toxicity consists of the eight combined repeated dose toxicity studies with the reproduction / developmental toxicity screening test (OECD guideline 422), which are also discussed in the RDT section 7.5. In addition, four prenatal developmental toxicity studies (OECD guideline 414) in rats and two prenatal developmental toxicity studies in rabbits (two rat studies and one rabbit study in each of the ‘linear’ and ‘mixed branched & linear’ subgroups, respectively) are available. A third prenatal developmental toxicity study in rabbits is currently ongoing. It has been delayed due to the high workload of the test facility. As soon as reliable results are available, the hazard assessment with respect to developmental toxicity in rabbits will be updated.

Certain effects were noted in several of the studies, although the effects were not always considered to be adverse or toxicologically relevant (please refer to the endpoint summary 7.5 Repeated dose toxicity for more details). As can be expected for surfactants with known irritating properties, some effects caused by irritation at the site of contact (fore-stomach) were observed in the studies in the rat. Only parameters relevant for reproductive and developmental toxicity are summarised in this section. The full assessment of the repeated dose toxicity parameters investigated in the OECD 422 studies is provided in the endpoint summary for IUCLID section 7.5. The effects observed in the combined repeated dose toxicity study with the reproductive / developmental toxicity screening tests are summarised and discussed below.

 

Reproduction / developmental screening studies (OECD guideline 422)

The combined repeated dose toxicity study with the reproductive / developmental toxicity screening test was performed according to OECD guideline 422 under GLP conditions. Groups of 10 rats per sex received the test substance by daily oral gavage, 7 days a week for a minimum of 28 days. A similarly constituted control group was dosed with the vehicle (corn oil) only. The dose levels were set based on the guideline recommendation for substances not expected to exhibit strong systemic toxicity. Males were treated for 29 days whereas females that delivered were treated for 50-64 days (14 days prior to mating, the variable time to conception, the duration of pregnancy and at least 13 days after delivery). Females that failed to deliver or had a total litter loss were treated for 40-43 days. The following parameters and endpoints were evaluated: mortality/moribundity, clinical signs, functional observations, body weight and food consumption, clinical pathology, measurement of thyroid hormone T4 and TSH (F0 males and females), gross necropsy findings, organ weights and histopathologic examinations. In addition, a number of reproduction / developmental parameters were investigated in the F0 parental generation: estrous cycle, qualitative evaluation of spermatogenesis, premating time, number of corpora lutea, implantation sites and pre- and post-implantation loss, gestation duration, parturition and maternal care. In the F1 offspring litter size, viability, sex ratio and early postnatal pup development (mortality, clinical signs, body weights, sex, anogenital distance, areola/nipple retention and macroscopy, measurement of thyroid hormone T4 in PND 14-16 pups) was recorded. The mating and fertility indices, and gestation index were calculated.

Parental effects

The parental findings of the OECD 422 studies that were considered systemic and local effects have been discussed in detail in the endpoint summary for section 7.5, and only a brief summary of the systemic and local effects is included here.

Some effects or changes that appeared characteristic of the AE substances were observed: clinical signs like salivation, a flat and/or hunched posture, abnormal breathing sounds and piloerection were noted particularly at the high-dose level. The increased liver weight and changes in liver histopathology were noted in most of the studies, and were most likely adaptive changes as a reaction to an increased metabolic burden due to gavage administration of substantial amounts of test substance. A reduced body weight (gain) observed in most of the studies was considered a result of general discomfort in rats administered the test substance. The specific cause of the histological changes in the jejunum, which were considered non-adverse, could not be identified. The changes in the non-glandular stomach and glandular stomach were caused by the irritant effect of the AE substances at the site of contact, and therefore considered a local effect. For one substance, hexadecan-1-ol, ethoxylated, the effect was considered adverse, leading to a LOAEL at the highest dose level.

There was no clear difference in the occurrence of treatment-related effects between the substances in the linear subgroup and the mixed branched & linear subgroup. The severity and prevalence of clinical signs, however, varied between some of the substances in the linear and in the mixed branched & linear subgroup. In the studies with the substances alcohols, C9-11, branched and linear, ethoxylated and alcohols, C12-13, branched and linear, ethoxylated of the mixed branched & linear subgroup, the severity and/or prevalence of clinical signs led to the conclusion that this was toxicologically relevant at the highest dose level. For these two substances this lead to a LOAEL for systemic toxicity at the highest dose level.     

In the OECD 422 studies, no toxicologically significant changes were noted in the reproductive parameters pre-coital time, number of implantation sites, post-implantation survival, duration of gestation, litter size, viability at delivery and maternal care. No treatment-related effects on spermatogenesis or the reproductive organs were observed. In the study with alcohols, C9-11, branched and linear, ethoxylated a disturbed oestrus cycle was found in 5/10 females and judged to be adverse. However, this finding occurred in only one of the eight OECD 422 studies, was not observed in any of the subchronic repeated dose toxicity studies and had no impact on the fertility of the females in the study with alcohols, C9-11, branched and linear, ethoxylated. Therefore, it is considered an incidental effect of no toxicological relevance for this or any other AE category member substance.

The mating, fertility, gestation and live birth indices were similar between the control and treatment groups, in all the studies. The (lack of) treatment-related effects on fertility between the substances in the linear subgroup and the mixed branched & linear subgroup was consistent across the subgroups and the category.

Effects on offspring

Slightly lower offspring body weight (gain) on post-natal day 0, 7 and/or 13, compared with the control, was noted in two of five studies with substances in the linear subgroup. As the changes were minor, they were not considered to be toxicologically relevant. In the studies with the three ‘mixed branched & linear’ AE substances alcohols, C9-11, branched and linear, ethoxylated; alcohols, C12-13, branched and linear, ethoxylated; and alcohols, C12-15, branched and linear, ethoxylated; a lower body weight of the pups was noted for animals in the high-dose group (1000 mg/kg bw/day). Based on the magnitude of the changes observed, the finding was considered adverse in all three studies. For alcohols, C9-11, branched and linear, ethoxylated; and alcohols, C12-13, branched and linear, ethoxylated; clear maternal systemic toxicity was noted at the same dose level and the effect was considered secondary to the maternal adverse effects. For alcohols, C12-15, branched and linear, ethoxylated, no clear maternal systemic toxicity was observed. The occurrence of body weight change in offspring without maternal toxicity is considered specific to this substance, as this is the only case among the eight studies. This study is therefore only considered relevant to alcohols, C12-15, branched and linear, ethoxylated and the data will not be read-across to other substances in the AE category. For the other substances in the mixed branched & linear subgroup, OECD 422 studies are available.

The severity of the reduced body weight development was the only clear difference in the occurrence of treatment-related developmental effects between the substances in the linear subgroup and the mixed branched & linear subgroup.

Incidental findings in relation to developmental toxicity include a test substance-related increased concentration of serum T4 levels in the study with alcohols, C12-14, ethoxylated and a decrease in the mean (normalised) anogenital distance of female pups in the study with hexadecan-1-ol, ethoxylated. These findings were considered non-adverse as they were not associated with an adverse effect or values were within the range of historical control data.

No toxicologically relevant changes were noted in any of the other developmental parameters that were included in the studies (viability index, lactation index, sex ratio and early postnatal pup development consisting of mortality, clinical signs, areola/nipple retention, and macroscopic examination).

Conclusion on toxicity to reproduction (fertility)

The data on reproduction toxicity from the combined repeated dose toxicity studies with the reproduction / developmental toxicity screening test (OECD guideline 422) give a consistent picture of the effects across the category. Treatment with AE substances did not lead to adverse effects on parental reproductive parameters, incl. mating and fertility indices, precoital time, number of implantations, spermatogenic profiling, and histopathological examination of reproductive organs. No toxicologically relevant alterations in most developmental parameters were observed, including litter size, sex ratio, anogenital distance, placental weights of live foetuses and early postnatal offspring development consisting of mortality, clinical signs, areola/nipple retention, and macroscopic examination. In two studies, performed with substances in the mixed branched & linear subgroup, reduced offspring body weight was observed at a dose inducing significant maternal toxicity and this was considered a secondary effect of the maternal toxicity. In one study, performed with a substance in the mixed branched & linear subgroup (alcohols, C12-15, branched and linear, ethoxylated) reduced offspring body weight was observed at the highest dose level without clear maternal systemic toxicity. As this was the only study among the eight studies in which an effect was observed on the offspring generation only, this is considered specific to this substance and not relevant to the category as a whole. The NOAELs for toxicity to reproduction (fertility) are given in Table 1 above.

For alcohols, C16-18 and C18 unsatd., ethoxylated (CAS No. 68920-66-1, EC No. 500-236-9) the following NOAELs are read across:

Oral (rat, m/f, OECD 422): NOAEL (reproduction) = 1000 mg/kg bw/day

Oral (rat, m/f, OECD 422): NOAEL (systemic toxicity) = 1000 mg/kg bw/day

Oral (rat, m/f, OECD 422): NOAEL (local toxicity) = 1000 mg/kg bw/day

For a detailed evaluation of the toxicity to reproduction potential of the substances in the AE category, please refer to the category justification attached to the category object.

Effects on developmental toxicity

Description of key information

Oral (rat, OECD 414): NOAEL (developmental toxicity) = 1000 mg/kg bw/day

Oral (rat, OECD 414): NOAEL (teratogenicity) = 1000 mg/kg bw/day

Conclusion based on data obtained with alcohols, C16-18 and C18 unsatd., ethoxylated (CAS No. 68920-66-1, EC No. 500-236-9) and considering all the available data on developmental toxicity in the Alcohol Ethoxylates (AE) category, in a Weight-of-Evidence approach.

Link to relevant study records

Reference

Reference 1

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

25 Aug - 29 Oct 2021

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Version / remarks:

adopted 2018

Deviations:

yes

Remarks:

Temperature was out of the target range for one day (minimum temperature of 17°C), without noticeable effect on the clinical condition of the animals or on the outcome of the study.

GLP compliance:

yes (incl. QA statement)

Remarks:

Health and Youth Care Inspectorate, Ministry of Health, Welfare and Sport, Utrecht, The Netherlands

Limit test:

no

Species:

rat

Strain:

Wistar

Remarks:

Crl: WI(Han)

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland, Sulzfeld, Germany
- Age at study initiation: 10 - 14 weeks
- Weight at study initiation: 185 – 264 g
- Fasting period before study: not applicable
- Housing: individually in polycarbonate cages (Makrolon type MIII, height 18 cm) containing sterilized wooden fibers as bedding material (Lignocel S 8-15, JRS-J.Rettenmaier & Söhne GmbH + CO. KG, Rosenberg, Germany)
- Diet: pelleted rodent diet (SM R/M-Z from SSNIFF® Spezialdiäten GmbH, Soest, Germany), ad libitum
- Water: municipal tap water, ad libitum
- Acclimation period: 5 - 6 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17 - 22
- Humidity (%): 55 - 69
- Air changes (per hr): at least 10
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 25 Aug To: 17 Sep 2021

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on exposure:

PREPARATION OF DOSING SOLUTIONS: The appropriate amount of the test material was mixed with the vehicle. The dose volume for each animal was based on the most recent body weight measurement and the dose formulations were stirred continuously during dosing.

VEHICLE
- Concentration in vehicle: 25 mg/mL (100 mg/kg bw/day), 75 mg/mL (300 mg/kg bw/day), 250 mg/mL (1000 mg/kg bw/day)
- Amount of vehicle: 4 mL/kg

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Chemical analyses of formulations were conducted twice during the study to assess accuracy and homogeneity using a gas chromatographic method with flame ionization detection (GC-FID).

The concentrations analyzed in the formulations of Groups 2, 3 and 4 for use in Weeks 1 and 2 were in agreement with target concentrations (i.e. mean sample concentration results were within or equal to 90 - 110% of target concentration).
No test item was detected in the Group 1 formulations.
The formulations of Groups 2 and 4 for use in Weeks 1 and 2 were homogeneous (i.e. coefficient of variation ≤ 10%).

Details on mating procedure:

- Impregnation procedure: not reported
Females were time-mated and arrived at the testing facility as such.

Duration of treatment / exposure:

Day 6 - 20 post-coitum

Frequency of treatment:

once daily, 7 days/week

Duration of test:

necropsy was performed on Day 21 post-coitum

Dose / conc.:

100 mg/kg bw/day

Remarks:

Group 2

Dose / conc.:

300 mg/kg bw/day

Remarks:

Group 3

Dose / conc.:

1 000 mg/kg bw/day

Remarks:

Group 4

No. of animals per sex per dose:

22

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale:
- Fasting period before blood sampling for (rat) dam thyroid hormones: No.
- Time of day for (rat) dam blood sampling: between 07.00 and 09.00 from the jugular vein.

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: At least once daily; starting on Day 6 post-coitum up to the day prior to necropsy.
Directly post dosing.

MORTALITY: Yes
- Time scheudle: At least twice daily beginning upon arrival through termination/release. Except on days of receipt and necropsy where frequency was at least once daily.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: On Days 2, 6, 15 and 21 post-coitum

BODY WEIGHT: Yes
- Time schedule for examinations: On Days 2, 6, 9, 12, 15, 18 and 21 post-coitum, intervals were calculated for Days 2-6, 6-9, 9-12, 12-15, 15-18 and 18-21, and 6 - 21 post-coitum.

FOOD CONSUMPTION: Yes
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/animal/day: Yes
- Time schedule: Over Days 2-6, 6-9, 9-12, 12-15, 15-18 and 18-21 post coitum, and 6 - 21 post-coitum.

WATER CONSUMPTION: Yes
- Time schedule for examinations: On regular basis throughout the study (monitored by visual inspection)

POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on Day 21 post-coitum
All animals from all groups were subjected to a gross necropsy. All gross lesions were collected.
- Organs weighed: thyroid, placenta
- Tissues collected for histopathology: thyroid gland and macroscopic abnormalities.
- Fixative: 10% buffered formalin
- Embedding media: paraffin
- Thickness of sections: 2 - 4 μm
- Staining: hematoxylin and eosin

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 of implantations: Yes
- Number of early resorptions: Yes
- Number of late resorptions: Yes
- Number of live and dead fetuses: Yes

Blood sampling:

- Plasma: Yes
- Serum: Yes
- Volume collected: 1.0 mL
- Parameters checked: Thyroid hormones, triiodothyronine (T3), thyroxine (T4) and thyroid-stimulating hormone (TSH).

Fetal examinations:

- External examinations: Yes: all per litter
- Soft tissue examinations: Yes: half per litter
- Skeletal examinations: Yes: half per litter
- Head examinations: Yes: half per litter
- Anogenital distance of all live rodent pups: Yes: all per litter
- Body weight: Yes: all per litter
- Sex: Yes: all per litter

Statistics:

Means, standard deviations (or % coefficient of variation or standard error, when deemed appropriate), percentages, numbers, and/or incidences are reported as appropriate by dataset. All statistical tests were conducted at the 5% significance level. All pairwise comparisons were conducted using two sided tests and were reported at the 1% and 5% levels, unless otherwise noted. All pairwise comparisons were conducted against the control group (Group 1).
The following statistical tests were used: Levene’s test, ANOVA F-test, Kruskal-Wallis Dunnett’s and Dunn’s test, ANCOVA, Fisher's exact test.

Indices:

Pregnancy rate (%): (No. of pregnant females)/(No. of mated females) * 100
Male fetuses (%): (No. of male fetuses)/(No. of fetuses) * 100
Female fetuses (%): (No. of female fetuses)/(No. of fetuses) * 100
Pre-implantation loss (%): (No. of corpora lutea – No. of implantations)/(No. of corpora lutea) * 100
Post-implantation loss (%): (No. of implantations – No. of live fetuses)/(No. of implantations) * 100
Litter % of fetuses with abnormalities: (No. of fetuses in litter with a given finding)/(No. of fetuses in litter examined) * 100

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

No clinical signs of toxicity were noted during the observation period.
Abnormal breathing sounds were noted in two females at 1000 mg/kg bw/day on 1 or 3 days after dosing. No toxicological relevance was attached to this finding, as it occurred incidentally and did not persist.
Salivation seen after dosing in another two females at 1000 mg/kg bw/day was regarded as a physiological response rather than a sign of systemic toxicity considering the nature and minor severity of the effect and its time of occurrence (i.e. after dosing).

Summarized results can be found in Attachment 2 in the attached background material.

Dermal irritation (if dermal study):

not examined

Description (incidence and severity):

not applicable

Mortality:

mortality observed, non-treatment-related

Description (incidence):

One control female was found dead on Day 18 post-coitum. At necropsy, clear oily content was found in the thoracic cavity, which indicates that this death was related to the gavage procedure. The female was pregnant with 13 (dead) fetuses.

Summarized results can be found in Attachment 2 in the attached background material.

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

No toxicologically relevant difference regarding body weight was observed between control and treatment groups up to and including the highest dose level.

At 300 mg/kg bw/day, slightly lower mean for gravid uterus weight compared to the control group was noted but attributed to the relatively low uterus weight of a single female which had three fetuses only.
At 1000 mg/kg bw/day, slightly lower mean body weight gain was recorded at start of dosing (Days 6-9 post-coitum) and end of dosing (Days 18-21 post-coitum), with mean body weight remaining slightly lower than for control throughout the entire dosing period. Terminal body weight and mean gravid uterus weight was 4 and 7% lower than control values, respectively. Body weight gain corrected for mean gravid uterus weight was 22.4 g vs 27.5 g for the control group (-18.5%). However, none of the differences reached statistical significance and all changes was considered non-adverse, considering their relative slight nature.

Summarized results can be found in Attachment 1 (Figures) and 2 (Tables) in the attached background material.

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

Mean food consumption at 100 mg/kg bw/day was similar to the control level over the study period.
At 300 mg/kg bw/day, a trend towards slightly lower mean food consumption was observed over Days 18-21 post-coitum (4% lower than control; not statistically significant). No toxicological relevance was attached to this finding, as the change was minimal only, with no effect on (terminal) body weight.
At 1000 mg/kg bw/day, mean food consumption was lower compared to control throughout the dosing period (not statistically significant over Days 15-18 post-coitum). The largest differences were observed during the first and last measurement interval (i.e. 12 and 11% lower than control over Days 6-9 and 18-21 post-coitum, respectively). Overall food intake during the dosing period was 10% lower in this high dose group, compared to control.


Summarized results can be found in Attachment 1 (Figures) and 2 (Tables) in the attached background material.

Food efficiency:

not examined

Description (incidence and severity):

not applicable

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

no effects observed

Description (incidence and severity):

No difference regarding water consumption was observed between control and treatment groups up to and including the highest dose level of 1000 mg/kg bw/day.

Ophthalmological findings:

not examined

Description (incidence and severity):

not applicable

Haematological findings:

not examined

Description (incidence and severity):

not applicable

Clinical biochemistry findings:

not examined

Description (incidence and severity):

not applicable

Endocrine findings:

effects observed, treatment-related

Description (incidence and severity):

No differences regarding thyroid hormones were observed between the control and treatment groups up to and including 300 mg/kg bw/day.

At 1000 mg/kg bw/day, T3 and T4 were decreased compared to the values of the control group (0.73x (0.33 ng/mL) and 0.86x (18.86 ng/mL) of control (0.454 ng/mL and 22.03 ng/mL), respectively) but remained within the available historical control data. At the individual level, however, 5/22 and 6/22 values for total T3 and T4, respectively, were below this range. Therefore, the change was considered test item related but possible adversity of these effects could not be assessed within this type of study and was therefore not taken into account when determining the maternal NOAEL.


Historical control data for pregnant Wistar Han rats (period 2020-2021):
Total T3 (ng/mL): mean = 0.439; P5 – P95 = 0.280 – 0.616 (n=263).
Total T4 (ng/mL): mean = 23.2; P5 – P95 = 16.3 – 35.2 (n=154).

Summarized results can be found in Attachment 2 in the attached background material.

Urinalysis findings:

not examined

Description (incidence and severity):

not applicable

Behaviour (functional findings):

not examined

Description (incidence and severity):

not applicable

Immunological findings:

not examined

Description (incidence and severity):

not applicable

Organ weight findings including organ / body weight ratios:

effects observed, non-treatment-related

Description (incidence and severity):

There were no changes in thyroid gland weights that were directly related to treatment with the test item up to 1000 mg/kg bw/day.
In all groups receiving the test item, the absolute and relative thyroid weight was slightly lower compared to the control group, but none of the differences reached statistical significance, there was no dose-relationship and no test item-related microscopic observations were noted. Therefore, the finding was not considered treatment related.

Summarized results can be found in Attachment 2 in the attached background material.

Gross pathological findings:

effects observed, non-treatment-related

Description (incidence and severity):

Macroscopic observations at necropsy did not reveal any alterations that were considered to have arisen as a result of treatment with the test item. There were no macroscopic findings in the thyroid gland.

The only finding noted was pelvic dilation in the left kidney of 1 female at 100 mg/kg bw/day, which was not considered treatment-related.

Summarized results can be found in Attachment 2 in the attached background material.

Neuropathological findings:

not examined

Description (incidence and severity):

not applicable

Histopathological findings: non-neoplastic:

no effects observed

Description (incidence and severity):

There were no test item-related microscopic observations in the thyroid glands in any control or treatment group up to and including the highest dose level.

Summarized results can be found in Attachment 2 in the attached background material.

Histopathological findings: neoplastic:

not examined

Description (incidence and severity):

not applicable

Other effects:

not examined

Description (incidence and severity):

not applicable

Number of abortions:

no effects observed

Description (incidence and severity):

No abortions occurred.

Pre- and post-implantation loss:

effects observed, non-treatment-related

Description (incidence and severity):

No toxicologically relevant difference regarding pre- and post-implantation loss was observed between the control and treatment groups up to and including the highest dose level.

A slightly lower pre-implantation loss was observed in all treated groups when compared to control, but none of the differences reached statistical significance. However, as the treatment started on Day 6 post-coitum (after implantation), the effect is not considered treatment-related.
A slightly higher mean post-implantation loss compared to the control group was observed in the 1000 mg/kg bw/day group (3.64 vs 1.01% in control), but the difference did not reach statistical significance and was mainly attributed to a single female which had four early resorptions next to ten live fetuses. It was therefore considered an isolated incidence.

Summarized results can be found in Attachment 2 in the attached background material.

Total litter losses by resorption:

no effects observed

Description (incidence and severity):

No total litter losses by resorption were observed in the control and treatment groups.

Summarized results can be found in Attachment 2 in the attached background material.

Early or late resorptions:

effects observed, non-treatment-related

Description (incidence and severity):

No late resorptions were observed in this study. One female at 1000 mg/kg bw/day had four early resorptions but this was not considered treatment related as the treatment started at a later time point.

Summarized results can be found in Attachment 2 in the attached background material.

Dead fetuses:

no effects observed

Description (incidence and severity):

Dead fetuses were only found in the control female found dead on Day 18 post-coitum. No dead fetuses were found in the treated groups.

Summarized results can be found in Attachment 2 in the attached background material.

Changes in pregnancy duration:

no effects observed

Description (incidence and severity):

No pre-mature deliveries occurred in this study.

Changes in number of pregnant:

no effects observed

Description (incidence and severity):

No difference regarding pregnancy rate was observed between the control and treatment groups up to and including the highest dose level. At scheduled necropsy, the number of females with viable litters for evaluation was 20, 22, 22, 22 in the control, 100, 300 and 1000 mg/kg bw/day groups, respectively.

Summarized results can be found in Attachment 2 in the attached background material.

Key result

Dose descriptor:

NOAEL

Remarks:

systemic toxicity

Effect level:

1 000 mg/kg bw/day

Based on:

test mat.

Basis for effect level:

other: No adverse effects were observed up to and including the highest dose level.

Key result

Abnormalities:

no effects observed

Fetal body weight changes:

effects observed, treatment-related

Description (incidence and severity):

No toxicologically relevant differences regarding fetal body weight were observed between the control and treatment groups up to and including the highest dose group.

At 1000 mg/kg bw/day, mean fetal weights (male, female and combined) were slightly decreased (3.0, 3.1 and 2.7% lower than control, respectively) but none of the differences reached statistical significance. Mean combined (male and female) fetal body weights were 5.2, 5.2, 5.2 and 5.0 gram for the control, 100, 300 and 1000 mg/kg/day groups, respectively. As the changes were slight, they were not considered adverse.

Summarized results can be found in Attachment 2 in the attached background material.

Reduction in number of live offspring:

no effects observed

Description (incidence and severity):

No differences regarding the number of live fetuses were observed between the control and treatment groups up to and including the highest dose group.

Summarized results can be found in Attachment 2 in the attached background material.

Changes in sex ratio:

no effects observed

Description (incidence and severity):

No difference regarding sex ratio was observed between the control and treatment groups up to and including the highest dose group.
Mean sex ratios (males:females) were 51:49, 49:51, 49:51 and 57:43 for the control, 100, 300 and 1000 mg/kg bw/day groups, respectively.

Summarized results can be found in Attachment 2 in the attached background material.

Changes in litter size and weights:

no effects observed

Description (incidence and severity):

Litter size was unaffected by treatment up to 1000 mg/kg bw/day.
Mean litter sizes were 11.8, 11.6, 11.4 and 11.2 live fetuses/litter for the control, 100, 300 and 1000 mg/kg bw/day groups, respectively.

Summarized results can be found in Attachment 2 in the attached background material.

Anogenital distance of all rodent fetuses:

no effects observed

Description (incidence and severity):

Anogenital distance (absolute and normalized for body weight) in male and female fetuses was considered not to be affected by treatment with the test item up to 1000 mg/kg bw/day.

Summarized results can be found in Attachment 2 in the attached background material.

Changes in postnatal survival:

not examined

Description (incidence and severity):

not applicable

External malformations:

no effects observed

Description (incidence and severity):

There were no external malformations or variations observed in any groups.

Summarized results can be found in Attachment 2 in the attached background material.

Skeletal malformations:

effects observed, non-treatment-related

Description (incidence and severity):

No toxicologically relevant differences regarding skeletal malformations were observed between the control and treatment groups up to and including the highest dose group.

Three fetuses presented skeletal malformations: 2 fetuses of the 300 mg/kg bw/day group had supernumerary lumbar vertebra, 1 fetus of the 1000 mg/kg bw/day group had small premaxillae. These findings were considered incidental due to the single or low occurrence and/or lack of a dose response.

Summarized results can be found in Attachment 2 in the attached background material.

Visceral malformations:

no effects observed

Description (incidence and severity):

Visceral malformations were not observed, and the only visceral variation that was noted (supernumerary liver lobes), occurred at low incidences across all groups.

Summarized results can be found in Attachment 2 in the attached background material.

Other effects:

no effects observed

Description (incidence and severity):

Mean placenta weight of live male and female fetuses was considered to be unaffected by treatment with the test item up to 1000 mg/kg bw/day.

Summarized results can be found in Attachment 2 in the attached background material.

Key result

Dose descriptor:

NOAEL

Remarks:

developmental toxicity

Effect level:

1 000 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No adverse effects were observed up to and including the highest dose level.

Key result

Abnormalities:

no effects observed

Key result

Developmental effects observed:

no

Conclusions:

The present study was conducted under GLP and according to OECD test guideline 414 (2018). Under the conditions of the study, administration of the test substance once daily by oral gavage for Days 6 - 20 post coitum was well tolerated in pregnant rats at levels up to 1000 mg/kg bw/day. The maternal and developmental No Observed Adverse Effect Levels (NOAELs) for the test item were set at 1000 mg/kg bw/day.

Reference 2

Endpoint:

developmental toxicity

Data waiving:

other justification

Justification for data waiving:

other:

Species:

rabbit

Effect on developmental toxicity: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

1 000 mg/kg bw/day

Study duration:

subacute

Species:

rat

Quality of whole database:

The available information comprises adequate and reliable (Klimisch score 1) studies performed with the registered substance. The selected study is thus sufficient to fulfil the standard information requirements set out in Annexes VIII - X, Section 8.7, of the REACH 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

Data on developmental toxicity are available for alcohols, C16-18 and C18 unsatd., ethoxylated (CAS No. 68920-66-1, EC No. 500-236-9) as well as several member substances of the Alcohol Ethoxylates (AE) category.

Study with alcohols, C16-18 and C18 unsatd., ethoxylated (CAS No. 68920-66-1, EC No. 500-236-9) 

Alcohols, C16-18 and C18-unsatd., ethoxylated (CAS No. 68920-66-1, EC No. 500-236-9) was administered to female Wistar (Crl: WI(Han) rats in a Prenatal developmental toxicity study according to OECD guideline 414 under GLP conditions (BASF, 2021). Groups of 22 dams were administered doses of 100, 300 and 1000 mg/kg bw/day by oral gavage, 7 days a week on gestation day 6 - 20. The control group was treated according to the same protocol and received the vehicle (corn oil) only. All the females were time-mated and the day of mating was Day 0 of gestation (Day 0 post-coitum). The dams were sacrificed on gestation day 21.

The following parameters were recorded in the dams: mortality/moribundity, clinical signs, body weight and food consumption, water consumption (monitored by visual inspection), thyroid weight, measurement of thyroid hormones (T3, T4 and TSH), macroscopic examination, gravid uterus weight, number of corpora lutea, number of implantations, number of early and late resorptions, and number of live and dead fetuses. The following parameters were recorded in the foetuses: litter size, body weight, sex, anogenital distance of all live pups, external examination, soft tissue examination, head examination and skeletal examination.

A control female was found dead on gestation day 18. The death was considered to be due to a gavage error, as oily content was found in the thoracic cavity at necropsy.

Salivation was seen following dosing on several occasions during gestation day 7 - 20 in 2/22 high-dose females. The salivation was not considered toxicologically relevant and was considered a physiological response of dosing rather than a sign of systemic toxicity. In the high-dose group 2/22 females had abnormal breathing sounds on gestation day 10 - 16. This was considered treatment-related but not adverse.

In the high-dose group the terminal body weight and mean gravid uterus weight was 4 and 7% lower than control values, respectively. As these differences were small and not statistically significant they were not considered as adverse and toxicologically relevant.

The food consumption was slightly reduced during the complete dosing period in high-dose females, compared with the control. The mean overall food intake was -10% compared to the control, but the difference did not reach statistical significance. In the mid-dose group, a trend towards slightly lower mean food consumption was observed over gestation day 18-21 (4% lower than control; not statistically significant).The reduced food consumption is not considered to be toxicologically relevant, as it was limited and did not affect the (terminal) body weight.

Triiodothyronine (T3) levels were statistically significantly decreased in high-dose females (0.73 x), compared with control. In addition, thyroxine (T4) levels were decreased in high-dose females (0.86 x), compared with control. All the mean values fell within the available historical control data range. At the individual level,0/22, 0/22, 1/22 and 5/22 females in the control, low- mid- and high-dose group showed T3 values below this range. Also,1/22, 2/22, 1/22 and 6/22 females in the control, low- mid- and high-dose group showed T4 values below this range. The changes may be treatment-related but their toxicological relevance could not be assessed in that type of study. Considering the fact that the mean values fell within the range of historical control data and no further effects related to a disturbance of the thyroid system were noted in the present study, they were not taken into account for the NOAEL determination.

No treatment-related effects were noted on mortality/moribundity, thyroid weight, macroscopic examination, litter loss, number of corpora lutea, number of pre- and post-implantations, number of early and late resorptions, and number of live and dead fetuses.

The maternal NOAEL systemic was set at ≥ 1000 mg/kg bw/day.

In the high-dose group the mean fetal body weights (male, female and combined) were slightly decreased compared with control (3.0, 3.1 and 2.7% lower than control, respectively; not statistically significant). The mean combined (male and female) fetal body weights were 5.2, 5.2, 5.2 and 5.0 g for the control, low- mid- and high-dose group, respectively. The limited changes do not indicate a treatment-related effect.

No external malformations or variations were observed. There were no treatment-related visceral malformations or variations. Three fetuses had a skeletal malformation. All these cases were considered incidental findings due to the single or low occurrence. No treatment-related effects were noted on litter size, sex ratio and anogenital distance.

The NOAEL developmental is 1000 mg/kg bw/day and the NOAEL teratogenicity is 1000 mg/kg bw/day.

Studies in the AE category

Studies investigating toxicity to developmental toxicity are available for the following AE substances (Table 1-3):

Table 1: Overview of OECD 422 studies, developmental toxicity

CAS No.	EC No.	Substance	Screening study (OECD 422)
			NOAEL developmental (F1) [mg/kg bw/day]	NOAEL systemic (F0) [mg/kg bw/day]
Linear subgroup
26183-52-8	500-046-6	Decan-1-ol, ethoxylated	≥ 950	≥ 950
68439-50-9	500-213-3	Alcohols, C12-14, ethoxylated	≥ 1000	≥ 1000
9004-95-9	939-518-5	Hexadecan-1-ol, ethoxylated	≥ 1000	≥ 1000 (local: 300)
68439-49-6	939-518-5	Alcohols, C16-18 (even numbered), ethoxylated, < 2.5 EO	≥ 1000	≥ 1000
9004-98-2	500-016-2	(Z)-9-Octadecen-1-ol ethoxylated	≥ 1000	≥ 1000
Mixed branched & linear subgroup
160901-09-7	500-446-0	Alcohols, C9-11, branched and linear, ethoxylated	300	300
160901-19-9	500-457-0	Alcohols, C12-13, branched and linear, ethoxylated	300	≥ 1000
106232-83-1	500-294-5	Alcohols, C12-15, branched and linear, ethoxylated	300	≥ 1000

 

Table 2: Overview of OECD 414 studies in the rat

CAS No.	EC No.	Substance	Prenatal developmental toxicity study (OECD 414) in the rat
			NOAEL [mg/kg bw/day]
			Systemic (maternal)	Development	Teratogenicity
Linear
68439-50-9	500-213-3	Alcohols, C12-14, ethoxylated	300	300	≥ 1000
68920-66-1	500-236-9	Alcohols, C16-18 and C18-unsatd., ethoxylated	1000	1000	1000
Mixed linear & branched
160901-09-7	500-446-0	Alcohols, C9-11, branched and linear, ethoxylated	800	800	800
106232-83-1	500-294-5	Alcohols, C12-15, branched and linear, ethoxylated	1000	1000	1000

 

Table 3: Overview of OECD 414 studies in the rabbit

CAS No.	EC No.	Substance	Prenatal developmental toxicity study (OECD 414) in the rabbit
			NOAEL [mg/kg bw/day]
			Systemic (maternal)	Development	Teratogenicity
Linear
68439-50-9	500-213-3	Alcohols, C12-14, ethoxylated	30	200	200
68920-66-1	500-236-9	Alcohols, C16-18 and C18-unsatd., ethoxylated	(study ongoing)	-	-
Mixed linear & branched
106232-83-1	500-294-5	Alcohols, C12-15, branched and linear, ethoxylated	100	400	400

 

Conclusion on developmental toxicity

All the data on developmental toxicity from the combined repeated dose toxicity study with the reproduction / developmental toxicity screening tests (OECD 422) and the prenatal developmental toxicity studies (OECD 414) in a rodent (rat) and a non-rodent species (rabbit) give a consistent picture of the effects across the category and species. Treatment with AE substances did not lead to adverse effects on most developmental parameters, including litter size, sex ratio, anogenital distance, placental weights of live foetuses and early postnatal offspring development consisting of mortality, clinical signs, areola/nipple retention, and macroscopic examination. In two studies, performed with substances in the mixed branched & linear subgroup, reduced offspring body weight was observed at a dose inducing significant maternal toxicity and this was considered a secondary effect of the maternal toxicity. In one study, performed with a substance in the mixed branched & linear subgroup (alcohols, C12-15, branched and linear, ethoxylated) reduced offspring body weight was observed at the highest dose level without clear maternal systemic toxicity. As this was the only study among the eight studies in which an effect was observed on the offspring generation only, this is considered specific to this substance and not relevant to the category as a whole. No teratogenic effects were observed. There was no clear difference in (lack of) reproductive and developmental and effects between the linear subgroup and the mixed branched & linear subgroup, indicating consistency across the category. 

The data on developmental toxicity and teratogenicity available for alcohols, C16-18 and C18 unsatd., ethoxylated (CAS No. 68920-66-1, EC No. 500-236-9) is consistent with the overall toxicity to reproduction data for AE substances.

 

The following NOAELs were set:

Oral (rat, OECD 414): NOAEL (developmental toxicity) = 1000 mg/kg bw/day

Oral (rat, OECD 414): NOAEL (teratogenicity) = 1000 mg/kg bw/day

 

For a detailed evaluation of the toxicity to reproduction potential of the substances in the AE category, please refer to the category justification attached to the category object.

Prenatal developmental toxicity in the second species (rabbit)

Pursuant to ECHA decision number CCH-D-2114493182-48-01/F a prenatal developmental toxicity studies by the oral route in the second species (rabbit) with alcohols, C16-18 and C18 unsatd., ethoxylated (CAS No. 68920 -66 -1, EC No. 500-236-9) according to OECD guideline 414 is currently ongoing. Once reliable results of the study are available, they will be reported in an updated dossier.

Justification for classification or non-classification

The available data on toxicity to reproduction obtained with alcohols, C16-18 and C18 unsatd., ethoxylated (CAS No. 68920-66-1, EC No. 500-236-9)  and with other members of the Alcohol Ethoxylates (AE) category do not meet the criteria for classification according to the CLP Regulation (EC) No. 1272/2008 and are therefore conclusive but not sufficient for classification.