Decan-1-ol, ethoxylated

Endpoint summary

Description of key information

For the whole category of alcohol ethoxylates (AE) a NOAEL of 500 mg/kg bw/day was established.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Reference 1

Endpoint:

sub-chronic toxicity: oral

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

Refer to the category justification provided in IUCLID Section 13

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across: supporting information

Reason / purpose for cross-reference:

read-across: supporting information

Reason / purpose for cross-reference:

read-across: supporting information

Reason / purpose for cross-reference:

read-across: supporting information

Reason / purpose for cross-reference:

read-across: supporting information

Reason / purpose for cross-reference:

read-across: supporting information

Reason / purpose for cross-reference:

data waiving: supporting information

Dose descriptor:

NOAEL

Remarks:

systemic

Effect level:

>= 500 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: see 'Remark'

Remarks on result:

other: Source, key, 68951-67-7, 1982

Critical effects observed:

no

Conclusions:

Daily oral exposure of male and female rats via the diet for 90 consecutive days to the test substance did not result in any toxicologically relevant effects. The NOAEL was determined to be > 500 mg/kg bw/day, corresponding to the highest dose tested.

Executive summary:

The oral repeated dose toxicity of the target substance is estimated based on an adequate and reliable subchronic oral toxicity key study performed with a structural analogue source substance. Daily oral exposure of male and female rats via the diet for 90 consecutive days to the test substance did not result in any toxicologically relevant effects. The NOAEL was determined to be > 500 mg/kg bw/day, corresponding to the highest dose tested. The result of the key study is further supported by additional (supporting) studies of various structural analogue source substances. Therefore, a systemic NOAEL after oral exposure for the target substance of > 500 mg/kg bw/day is established. As explained in the category justification, the differences in molecular structure between the target and the source substances are unlikely to lead to differences in oral repeated dose toxicity.

Reference 2

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

equivalent or similar to guideline

Guideline:

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

GLP compliance:

no

Limit test:

no

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Shell Toxicology Laboratory
- Age at study initiation: 5 weeks
- Mean body weight at study initiation: 138 - 143 g (males), 130 - 132 g (females)
- Housing: animals were individually housed in suspended polypropylene cages which had stainless steel grid floors and cellulose-lined trays underneath (North Kent Plastic Cages Ltd., Dartford, Kent, UK)
- Diet: expanded powdered diet (Spratts Laboratory diet No. 2, LAD 2, Spratts Patent Ltd., Barking, Essex, UK), formulated with the appropriate amount of test material, ad libitum
- Water: ad libitum
- Acclimation period: 14 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C):18.3 - 24.4
- Humidity (%): 45 - 70
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

DIET PREPARATION
- Mixing appropriate amounts with LAD 2: Diet containing 10000 ppm of the test material was prepared by mixing the melted material with acetone in the ratio of 2:1 w/v to make a uniform mix with LAD 2 powdered diet. The 3000 ppm and 1000 ppm concentrations were prepared by mixing the 10000 ppm diet with the appropriate amount of untreated diet and the 300 ppm concentration was prepared by mixing the 3000 ppm diet with the appropriate amount of untreated diet. The plain diet for the control group was prepared with acetone.
- Storage temperature of food: ambient temperature
- Rate of preparation of diet (frequency): The diets were prepared in three batches.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The analytical method used is based upon the method of Tobin et. al. (1976) The test material is extracted, degraded and derivatised with hydrogen bromide in acetic acid into 1,2-dibromoethane, 1-bromotetradecane and 1-bromopentadecane. These derivatives are analysed and quantified by gas-liquid chromatography as a measure of the test material content.
The recovery based on the derivate 1,2-dibromoethane was 103, 114 and 146% at 10000, 3000 and 1000 ppm; 106, 97 and 128% at 10000, 3000 and 1000 ppm and 104% at 10.000 ppm for the first, second and third batch of diet, respectively.
The recovery based on the derivate 1-bromotetradecane was 103, 102 and 90% at 10000, 3000 and 1000 ppm; 96, 75 and 106% at 10000, 3000 and 1000 ppm and 105 and 102% at 10.000 ppm for the first, second and third batch of diet, respectively. Due to interference with dietary peaks the recovery was repeated using a modified protocol. The recovery based on the derivate 1-bromotetradecane was 114, 102, 104 and 90% at 10000, 3000, 1000 and 300 ppm; 75, 84 and 96% at 3000, 1000 and 300 ppm for the first and second batch of diet, respectively.
The recovery based on the derivate 1-bromopentadecane was 108, 111 and 79% at 10000, 3000 and 1000 ppm; 91, 69 and 105% at 10000, 3000 and 1000 ppm and 134 and 87% at 10.000 and 300 ppm for the first, second and third batch of diet, respectively.
Re-analysis of the 300 ppm diet of batch 3 proved the stability of the test material in the diet (102 vs 93% based on the derivate 1-bromotetradecane and 87 vs. 93% based on the derivate 1-bromopentadecane.
Although not all results were within the protocol specification of ± 10% the analytical verification proved the nominal dose level.
Reference: Tobin et al. 1976, Water Research, 10 (6), 529-535

Duration of treatment / exposure:

13 weeks

Frequency of treatment:

daily, 7 days/week

Dose / conc.:

300 ppm

Remarks:

nominal in diet

Dose / conc.:

1 000 ppm

Remarks:

nominal in diet

Dose / conc.:

3 000 ppm

Remarks:

nominal in diet

Dose / conc.:

10 000 ppm

Remarks:

nominal in diet

Dose / conc.:

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

Dose / conc.:

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

Dose / conc.:

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

Dose / conc.:

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

No. of animals per sex per dose:

24 (control), 12 (dose groups)

Control animals:

other: plain diet mixed with acetone

Positive control:

Not applicable

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
Time schedule: All animals were daily examined for overt signs of toxicity, ill-health, mortality or behavioural change.

DETAILED CLINICAL OBSERVATIONS: No

BODY WEIGHT: Yes
Time schedule for examinations: Individual body weights were recorded on Day 0 (prior to dosing) and at weekly intervals thereafter. Body weights were also recorded at terminal kill.

FOOD CONSUMPTION: YES
- Food consumption was recorded at weekly intervals.

WATER CONSUMPTION: No Data

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- Time schedule for collection of blood: Haematological investigations were performed on all animals from each test and control group at the end of the study (13 weeks). Terminal blood samples were taken by cardiac puncture. Moreover, blood for the estimation of glucose concentration was obtained from the tail vain of all rats during the eleventh week.
- Animals fasted: No
- How many animals: all animals
- Parameters examined: haemoglobin (Hb), haematocrit (Hct), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), erythrocyte count (RB), total leukocyte count (WBC) mean cell volume (MCV), prothrombin time (PT), kaolin cephalin clotting time (KCCT), differential leucocyte count, reticulocyte count

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: During the eleventh week blood for the estimation of glucose concentration was obtained from the tail vain of all rats. Clinical chemistry investigations were performed on all animals from each test and control group at the end of the study (13 weeks). Terminal blood samples were taken by cardiac puncture.
- Animals fasted: No
- How many animals: all animals
- Parameters examined: urea nitrogen, total protein, alkaline phosphatase, chloride (Cl-), bilirubin, calcium, sodium (Na+), potassium (K+), cholesterol, glucose, alanine amino transferase (ALT), aspartate amino transferase (AST)

URINALYSIS: Yes
- Time schedule for collection of urine: Urine was collected from 10 male and 10 female rats from each of the control and 10000 ppm dose groups during the eleventh week.
- Metabolism cages used for collection of urine: No data
- Animals fasted: No
- Parameters examined: volume, pH, nitrite, protein, glucose, ketone, urobilinogen, bilirubin, blood, epithelial cells, tubule cells, leucocytes, erythrocytes, sperm, casts, bacteria, triple phosphate

NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes

HISTOPATHOLOGY: Yes
- full histopathology was performed with tissues from control, 3000 and 10000 ppm dose groups including: mammary gland, mesentheric and submandibular lymph nodes, pancreas, stomach, intestine at 6 levels, spleen, liver, adrenals, kidneys, ovaries, testes, uterus, prostate, seminal vesicles, urinary bladder, thyroids with oesophagus and trachea, heart, lungs, thymus, eyes and lachrymal glands, salivary gland, brain, spinal cord, pituitary, tongue, sciatic nerves, muscle, knee joint and femur

Other examinations:

ORGAN WEIGHT:
- The following organs, removed from animals that were killed at study termination (13 weeks) were weighed: brain, heart, liver, spleen, kidneys, testes, ovaries,

Statistics:

Body and organ weights were analysed by covariance analysis using initial bodyweight as the covariate. Reported means were adjusted for initial bodyweight if a significant covariance relationship existed; where no significant covariance relationship was found, unadjusted means were reported. Organ weights were further examined by covariance analysis using the terminal bodyweight as the covariate. The organ weight means are reported as adjusted for terminal bodyweight if a significant covariance relationship existed; the absence of a significant covariance relationship is indicated where appropriate. Food intakes, clinical chemical and haematological variates were examined using a two-way analysis of variance. The significance of any difference between treated and control group means was tested using the Williams “t” test. On occasions where a monotonic dose response was not seen Dunett´s test was used.

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

significantly decreased body weight in the 10000 ppm group (both sexes) and in the 3000 ppm group (females) (non-adverse)

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

significantly decreased mean food intake in the 10000 ppm group (both sexes) (non-adverse)

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

effects observed, treatment-related

Description (incidence and severity):

significantly increased WBC, absolute lymphocytes in the 3000 ppm and 10000 ppm group (males); significantly increased WBC, lymphocytes and significantly decreased mean cell volume, mean cell haemoglobin in the 10000 ppm group (females) (non-adverse)

Clinical biochemistry findings:

effects observed, treatment-related

Description (incidence and severity):

significantly increased urea, calcium, potassium in the 10000 ppm group (males); significantly increased urea, chloride, calcium, cholesterol in the 10000 ppm group (females) (non-adverse)

Urinalysis findings:

no effects observed

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Description (incidence and severity):

significantly increased liver weights in the 1000 ppm (females), 3000 and 10000 ppm (males) group; significantly increased spleen weight in the 10000 ppm group (males); significantly increased kidney weights in the 1000 ppm group (females) (non-adverse)

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

not examined

Details on results:

CLINICAL SIGNS AND MORTALITY
There were no treatment-related clinical signs in either sex throughout the study. No mortality occurred during the entire study period.

BODY WEIGHT AND WEIGHT GAIN
The mean body weights of males fed 10000 ppm and of females fed 10000 ppm and 3000 ppm of the test material were significantly lower throughout the study period when compared to the control group. It seems clear that this was directly attributable to the reduced intake of an unpalatable diet. Further evidence of this was the increased food spillage in the same treatment groups (refer to table 1).

FOOD CONSUMPTION AND COMPOUND INTAKE
The food intakes of males and females fed 10000 ppmof the test material were significantly lower throughout the study when compared to the control group. Males and females in the 3000 ppm treatment group had lower food intakes, but these were only statistically significantly lower than control values at week 3 (males) and at weeks 5, 8, 10, 12 and 13 (females). The food spillage by both males and females fed 10000 ppm of the test material was higher than in other treatment groups (refer to table 2).

HAEMATOLOGY
In one or both sexes fed 10000 ppm of the test material, values of total leukocytes and absolute lymphocytes were significantly increased and values of absolute neutrophils, percentage neutrophils, mean cell volume, mean cell haemoglobin, and prothrombin time were significantly decreased when compared with controls. In the 3000 ppm group only the male values of total leukocytes, absolute lymphocytes and prothrombin time differed significantly from those of male controls (refer to table 3).

CLINICAL CHEMISTRY
In rats fed 10000 ppm of the test material, plasma concentrations of urea, potassium, chloride, calcium and cholesterol and the plasma activity of alkaline phosphatase were significantly increased in one or both sexes, when compared with the control group. At lower dietary concentrations, the only difference from control was the significantly elevated plasma concentration of urea in 1000 ppm and 3000 ppm females (refer to table 6).

ORGAN WEIGHTS
When compared to control, heart and kidney weights of both sexes, brain weights of males and spleen weights of females all had significantly lower mean values in the 10000 ppm group when unadjusted or adjusted for initial body weight but not after adjustment for terminal body weight. Liver weights of males in the 3000 ppm and 10000 ppm groups were significantly increased (when unadjusted and after adjustment for terminal body weight). Liver weights of females in the 1000 ppm and higher treatment groups showed a significant increase after adjustment for terminal body weight; adjustment for initial body weight showed a significant difference only at the 1000 ppm level. Adjustment for terminal body weight showed a significant increase in the spleen weight of males in the 10000 ppm group when compared with the controls. Females in the 1000 ppm group showed significantly increased kidney weights when adjusted for initial body weight and when adjusted for terminal body weight (refer to tables 5 and 6).

GROSS PATHOLOGY
No treatment-related macroscopic abnormalities were identified at necropsy.

HISTOPATHOLOGY
Histological examination revealed no specific effects attributable to exposure to the test material; neither the incidence nor the severity of spontaneous background lesions was significantly influenced by treatment.

Dose descriptor:

NOAEL

Remarks:

systemic

Effect level:

>= 500 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: see 'Remark'

Critical effects observed:

no

Table 1: Mean body weights for rats for 13 weeks

Dietary concentration [ppm]	Number of animals	Mean body weight [g] at week
		0	1	2	3	4	5	6	7	8	9	10	11	12	13
Males 0 300 1000 3000 10000	24 12 12 12 12		+ a	+	+	+ a	+	+	+ a	+	+	+	+	+	+
		143	203	244	294	337	361	384	403	421	433	442	448	460	468
		143	202	243	292	332	358	379	397	413	427	440	449	462	466
		142	204	246	295	336	361	380	402	416	432	442	453	467	471
		141	201	242	289	333	356	377	399	416	430	440	451	459	466
		138	178**	215**	258**	292**	316**	331**	350**	364**	375**	386**	388**	398**	409
SD of a single observation		9.4	4.7	6.3	9.4	11.6	12.8	14.3	14.4	16.1	17.6	18.6	19.7	21.6	22.2
Females 0 300 1000 3000 10000	24 12 12 12 12		+	+	+	+	+	+	+	+	+	+	+	+	+
		130	161	183	207	224	239	247	259	270	276	283	285	291	294
		131	162	183	205	223	235	244	256	266	274	281	286	291	293
		132	162	185	207	226	241	151	262	270	279	286	287	294	296
		132	158*	178*	199*	214**	226**	233**	246**	253**	262**	267**	269**	274**	276**
		130	141**	160**	180**	193**	201**	211**	223**	226**	234**	238**	237**	241**	242**
SD of a single observation		7.6	3.4	5.8	8.6	10.4	11.4	12.5	12.9	12.7	13.0	13.0	13.2	14.3	14.3

+: adjusted for initial body weight

*: p ≤0.05

**: p ≤0.01

a: body weight measured 1 day late

SD: standard deviation

Table 2: Mean food intake for rats for 13 weeks

Dietary concentration [ppm]	Number of animals	Mean food intake [g] at week
		1	2	3	4	5	6	7	8	9	10	11	12	13
Males 0 300 1000 3000 10000	24 12 12 12 12	a	b		a	b		a	b
		182	152	187	217	160	178	213	162	181	179	171	176	174
		183	150	185	216	163	170	206	157	179	181	177	181	171
		181	150	186	217	161	171	207	154	178	182	180	183	171
		180	150	178*	216	155	172	211	158	179	179	176	173	167
		146**	130**	161**	192**	140**	148**	180**	133**	150**	162**	144**	154**	151**
SD of a single observation		9.2	8.1	10.3	10.0	10.3	14.5	11.1	10.2	9.7	13.3	10.6	13.9	12.6
Females 0 300 1000 3000 10000	24 12 12 12 12
		133	135	142	145	138	138	150	150	145	150	138	146	139
		136	136	139	141	138	126	145	144	144	147	141	139	134
		134	137	139	145	145	141	152	144	150	149	145	148	140
		127	130	138	137	129*	125	145	137**	136	141**	136	136*	129**
		97**	121**	125**	124**	117**	114**	135**	118**	126**	120**	115**	122**	108**
SD of a single observation		8.5	10.2	12.5	13.3	10.2	17.9	13.9	9.7	15.4	8.7	10.2	10.6	9.9

+: adjusted for initial body weight

*: p≤0.05

**: p≤0.01

a: food intake measured over an 8 day period

b: food intake measured over a 6 day period

SD: standard deviation

Table 3: Mean haematological values for rats for 13 weeks

Dietary concentration [ppm]	Number of animals	Haematology parameters
		WBC x10^3/cmm	RBC x10^6/cmm	Hb g/100 mL	Hct %	Mean cell volume µ3	Mean cell haemoglobin pg	Platelets	Mean cell haemoglobin concentration g/100 mL	P.T. sec		KCCT sec
Males 0 300 1000 3000 10000	24 12 11 11 12
		3.91	7.93	15.3	42.0	54	19.5	543.6	36.5	15.4		30.0
		4.18	7.90	15.3	42.0	54	19.5	560.8	36.5	15.5		31.7
		3.99	7.94	15.3	42.0	54	19.4	544.1 A	36.6	15.2 A		28.7 A
		4.50*	8.12	15.4	42.3	53	19.1	558.8	36.5	14.4*		27.0
		4.64**	7.96	15.4	42.7	54	19.5	571.4	36.2	14.4*		28.2
SD of a single observation		0.71	0.287	0.43	1.27	1.2	0.45	74.51	0.48	1.35		5.47
Females 0 300 1000 3000 10000	22 12 12 11 12
		2.63	7.41	15.1	41.4	56	20.5	531.0	36.5	12.8	21.9
		2.66	7.49	15.2	41.3	55	20.4	516.7	36.9	12.6	21.9
		2.83	7.44	15.1	41.6	56	20.5	522.1	36.5	13.0	22.3
		2.70	7.61	15.4	42.2	55	20.4	546.9	36.6	12.7	21.5
		3.02*	7.53	14.9	41.0	54**	19.9**	586.7	36.4	13.0	21.5
SD of a single observation		0.504	0.324	0.55	1.48	1.1	0.43	85.02	0.42	0.60	2.07

*: p≤0.05

**: p≤0.01

SD: standard deviation

A: based on 12 observations

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

500 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Reliable studies have been conducted with C16-18 AE10 (CAS 68920-66-1), C9-11AE6 (CAS 68439-46-3), C14-15AE7 (CAS 68951-67-7), PEG 200 and PEG 400 (CAS 25322-68-3), C12AE0 (CAS 112-53-8) and C16AE0 (CAS 36653-82-4). The presented studies of AEs are all conducted with higher ethoxylated alcohols than are intended to be registered; e.g. EO6-7 instead of EO1-2.5. Since AEs with an ethoxylation degree of 1 to 2.5 contain a considerable amount of the corresponding free alcohol and alcohols represent as well the class EO0, studies conducted with pure alcohols are used to validate the read-across.It is expected that the toxicity of AEs increases with increasing grade of ethoxylation, while the alkyl chain length does not have a meaningful influence on the toxicity (see section Acute Toxicity). Therefore, polyethylene glycol having no alkyl chain (PEG 200 and 400, corresponding to approximately 4 and 8 EO) were also used for read-across.

Repeated dose toxicity: oral

Subchronic dietary NOAELs were deduced from two 90-day repeated dose toxicity study with C9-11AE6 (CAS 68439-46-3) and C14-15AE7 (CAS 68951-67-7). In a good quality feeding key study, C14-15AE7 (CAS 68951-67-7) was fed to Wistar rats at dietary concentrations of 0, 300, 1000, 3000 and 10,000 ppm of active ingredient which corresponded to daily doses of ca. 0, 15, 50, 150 and 500 mg/kg bw/day (Shell, 1982). No effects on the general health and behaviour of treated rats were evident. Significant treatment-related effects on body weight, food intake, organ weights, clinical chemistry and haematology were identified in one or both sexes at daily doses of 150 and 500 mg/kg bw/day. Due to the fact that no compound-related gross or histopathological lesions were identified at any dose level, the changes reported are considered minor and not of toxicological significance. Hence, the NOAEL for systemic toxicity was set to greater than 500 mg/kg bw/day.

Moreover, the toxicity of C9-11AE6 (CAS 68439-46-3) was evaluated in a supporting feeding study at dietary concentrations of 0, 125, 250, 500, 1000 and 3000 ppm corresponding to approx. 0, 6.25, 12.5, 25, 50 and 150 mg/kg bw/day (Shell, 1973). The results showed that oral exposure to up to 3000 ppm in the diet to rats produced no significant signs of toxicity. A NOEL or NOAEL was not established by the investigators, but based on the information presented the NOAEL was set at the dose level of greater than 150 mg/kg bw/day.

Moreover, in one subchronic feeding and two subchronic drinking water studies reported by Smyth (1950, 1955), rats were administered with polyethylene glycol (PEG 200; CAS 25322-68-3) for 90 days at concentrations of 2, 4, 8, 16 and 24 % in diet or 4, 8 and 16% in drinking water. Due to observed effects such as mortality and reduced water intake in the drinking water study (at doses of 4% and above) as well as decreased nutrient consumption and increased liver and kidney weights in the oral feed study (at doses of 16% and above) a NOAEL of 2% which corresponds to a dose of 1000 mg/kg bw/day was determined.

In chronic feeding studies reported by Smyth (1950, 1955), rats and dogs were fed with polyethylene glycol (PEG 400; CAS 25322-68-3) for two and one year, respectively. At a level of 2% in the diet which corresponds to a dose of 1000 and 500 mg/kg bw/day, respectively no adverse effects were observed.

1-Dodecanol (CAS 112-53-8) was tested in rats in a combined repeated-dose and reproductive/developmental toxicity screening (Hansen, 1992). Animals received dietary concentrations of 1500, 7500 or 30,000 ppm during all phases in the production of a single generation; the composition of the diet was adjusted to take account of the caloric incorporation of the test material. In males, there were no effects recorded other than a reduction in mean white blood cell count (15, 38 and 32% reduction for the low mid or high dose group, respectively) and changes in free cholesterol (38% reduction in the mid dose group) and triglycerides (46% reduction at the top dose level). In the absence of any changes in the differential white cell count, the observed reduction in total WBC is considered of uncertain significance. A reduction in plasma cholesterol was observed in the middle dose group; this was considered a chance finding associated with 2 outlying values. Although the reduction in plasma triglycerides and cholesterol levels may be indicative of marginal effects in the liver, the differences in composition of the test diets between control and the treatment groups may have confounded some of the parameters measured in this study. The NOAEL was set at 30,000 ppm (2000 mg/kg bw/day).

In a 13-week study in rats 1-hexadecanol (CAS 36653-82-4) was administered in the diet at concentrations of 0, 1, 2.5 or 5%; the level in the highest dose group being increased stepwise to 10% during the last 3 weeks of the study (Scientific Assoc., 1966). Reductions in body weight gain (82-90% of control values) and food consumption (76 – 90% of control values) in the highest dose group and, occasionally, at the 2.5% level were the main findings of this study. Relative liver weights were increased in males at the top dose level (124% of control values) but in the absence of any microscopic findings the significance of this change is uncertain. A NOAEL was established at a dietary concentration of 1% (equivalent to ca.750 mg/kg bw/day) based on the reductions in body weight gain and food consumption.

Gastrointestinal irritation, particularly of the forestomach, was the primary effect after application via gavage but not after application via the diet. This is consistent with the slight irritant properties of the AE and the bolus effect after application by gavage. Moreover, administration via gavage does not allow differentiating between systemic effects as a consequence of the local irritation or due to specific substance properties. Hence, the NOAEL used for the risk assessment should be based on a dietary study to avoid too conservative assumptions.

All dietary NOAELs and LOAELs are listed in the table below. 

Dietary NOAELs and LOAELs (a.i.) for repeated dietary dose toxicity studies of AE

Substance	Duration (weeks)	NOAEL (mg/kg bw/day)	LOAEL (mg/kg bw/day)	Reference
C9-11AE6	13	150	>150	Shell (1973)
C14-15AE7	13	500	>500	Shell (1982)
PEG 200	13	1000	>1000	Smyth (1950/1955)
PEG 400	52/104	500/1000	>500/>1000	Smyth (1955)
Only for validation of read-across
C12AE0	13	2000	>2000	(Hansen 1992)
C16AE0	13	750	1875	Scientific Assoc. (1966)

No LOAELs could be detected in the presented studies with ethoxylated substances, i.e. all NOAELs represented the highest dose level used. Therefore the NOAEL of 150 mg/kg bw/d from Shell (1973) is low due to the dose levels used. This NOAEL is expected to be unrealistic low for risk assessment. To avoid an underestimation of risks after repeated dose the NOAEL of 1000 mg/kg bw/d (Smyth, 1950/1955) was disregarded as well for a conservative approach. Thus, the NOAEL of 500 mg/kg bw/d (Shell, 1982) was chosen for risk assessment.

The available oral toxicity studies provide a coherent picture on the subchronic and chronic oral toxicity of AE. Based on the described effects and argumentations, the dietary NOAEL of 500 mg/kg bw/day (Shell, 1982) representing an average of all NOAELs, was chosen for the risk assessment.

Disregarded study

In the subchronic oral gavage study, C16-18AE10 (CAS 68920-66-1) was tested for systemic toxicity at doses of 0, 20, 100 and 500 mg/kg bw/day (BASF, 1983). The highest dosage resulted in delayed growth of the male animals and caused damage to forestomach and kidneys in both male and female rats. No effects were observed on the organs of the reproductive system. The delayed body weight gain was presumably due to the irritating properties of the substance. The body weight gain of females was decreased at the highest dose level when compared to control also, but did not reach statistical significance. Effects on kidneys were reported to be related to calcinosis. The author stated that rats seem to have a disposition for calcinose as this effect can also be induced with other essential substances. Taken into account the high actual intake of test substance the calcinose was deemed to be not relevant. In addition in none of the feeding studies damaged kidneys were reported. Thus this finding was by chance or due to the bolus application. Inflammatory changes in the forestomach, seen in the animals in the middle dosage range (i.e., 100 mg/kg bw/day) were less obvious and were reversible. These effects were most likely due to the gavage administration of an irritant concentration of the test substance as similar observations were not made in the dietary studies. On the basis of the observations made in this study, a NOAEL of 100 mg/kg bw/day can be established.

Justification for classification or non-classification

According to the classification criteria of Regulation (EC) No. 1272/2008 the substance does not need to be classified for repeated dose toxicity.