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Administrative data

Description of key information

A NOAEL of > 750 mg/kg bw/day was derived based on no treatment-related effects at any of the dose levels in a 28 day oral toxicity study conducted on structurally similar amides, C12-18 (even-numbered) and C18-unsatd., N,N-bis(hydroxyethyl). A 90 day oral study conducted on the structurally similar substance lauric acid diethanolamine condensate (LDEA, CAS No.120-40-1) from which a NOEL of 50 mg/kg bw/day was established showed effects at higher dose levels, however it is unclear whether the effects were related to the test substance itself or a result of nutritional deficiencies due to the unpalatability of the diet, as evidenced by scattering of food (Sharrat et al., 1961). In conclusion, the subacute oral rat NOAEL of 750 mg/kg bw/day was selected as the point of departure for the safety assessment.
Dermal 90 day and 2 year studies have been conducted in both rats and mice. The following dose descriptors were derived:
• Subacute dermal rat NOAEL: 50 mg/kg bw/day based on renal tubule regeneration
• Subacute dermal mouse NOAEL: 100 mg/kg bw/day organ-weight changes
• Chronic dermal rat NOAEL: 50 mg/kg bw/day based on skin irritation at site of application in the 100 mg/kg bw dose (females) and significant increases in the epithelial ulcer of the forestomach
• Chronic dermal mouse LOAEL: 100 mg/kg bw/day based on body weight changes and skin irritation at site of application in the 200 mg/kg bw dose (females) and several non-neoplastic lesions at all dose levels
Since both subchronic and chronic dermal studies are available for structurally similar amides, C8-18 and C18-unsatd., N,N-bis(hydroxyethyl) and the NOAELs for both studies in rats were set at 50 mg/kg bw/day, the NOAEL from the chronic rat study will be further used in the safety assessment as the point of departure since a chronic study takes precedence over a subchronic study, therefore reducing the uncertainty level when deriving the DNEL dermal value of long term systemic effects.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records
Reference
Endpoint:
short-term repeated dose toxicity: oral
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
1983
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Well conducted and comparable to guideline study, no information on GLP status
Justification for data waiving:
other:
Reason / purpose:
reference to same study
Reason / purpose:
reference to other study
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 407 (Repeated Dose 28-Day Oral Toxicity in Rodents)
Deviations:
not specified
Principles of method if other than guideline:
Not applicable
GLP compliance:
no
Limit test:
no
Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Mus-Rattus, Brunntal, Germany
- Strain: Wistar rat, MuRa Han 67 SPF
- Age at study initiation: between 6-7 wk
- Weight at study initiation: 109 (f) - 114 (m) g
- Housing: plastic cages, 3 males and 5 females/cage
- Diet (e.g. ad libitum): ad libitum (Altromin Ratdiet No. 1424 DK, Altromin GmbH, Lage, Germany)
- Water (e.g. ad libitum): ad libitum (tap water)
- Acclimation period: 6 d

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-22
- Humidity (%): 60-80
- Air changes (per hr): 11
- Photoperiod (hrs dark / hrs light): 12/12
Route of administration:
oral: gavage
Vehicle:
olive oil
Details on oral exposure:
Doses were adapted weekly to the body weight; application volume - 5 mL/kg bw
Analytical verification of doses or concentrations:
no
Details on analytical verification of doses or concentrations:
no information
Duration of treatment / exposure:
28 d
Frequency of treatment:
daily once, 5 times/wk
Remarks:
Doses / Concentrations:
70 mg/kg bw/d (Days 1-28)
Basis:
actual ingested
Remarks:
Doses / Concentrations:
250 mg/kg bw/d (Days 1-28)
Basis:
actual ingested
Remarks:
Doses / Concentrations:
750 mg/kg bw/d (Days 1-14)
Basis:
actual ingested
Remarks:
Doses / Concentrations:
1500 mg/kg bw/d (Days 15-28)
Basis:
actual ingested
No. of animals per sex per dose:
10/sex/dose for main; 5/sex/dose for 4 month recovery period
Control animals:
yes, concurrent vehicle
Details on study design:
according to standard procedure
Positive control:
not necessary
Observations and examinations performed and frequency:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily


DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: end of study


BODY WEIGHT: Yes
- Time schedule for examinations: weekly


HAEMATOLOGY: Yes
- Time schedule for collection of blood: end of study
- Anaesthetic used for blood collection: Yes (ether)
- How many animals: 10 per dose and sex
- Parameters checked: Hematocrit, erythrocytes, leukocytes, hemoglobin, thrombocytes, mean corpuscular volume, white blood cell differential


CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: end of study
- How many animals: 10 per sex and dose
- Parameters checked: GPT, GOT, AP, glucose, urea, total protein, calcium, phosphate, cholesterol


URINALYSIS: Yes
- Time schedule for collection of urine: end of study
- Metabolism cages used for collection of urine: No
- Parameters checked: urea, creatinine, sodium, potassium, glucose, calcium, ap


NEUROBEHAVIOURAL EXAMINATION: No

Other: Groups of 5 male and 5 female rats kept for an additional 4 month recovery period.

Sacrifice and pathology:
GROSS PATHOLOGY: Yes
the following tissues/organs were examined:
adrenal gland (2)
aorta thoracica
brain (cornu ammonis)
coagulating gland with seminal vesicle
epididymis (2)
eye with optic nerve (2)
heart
intestine, large
intestine, small
kidney (2)
liver
lungs
lymph node (cervical) (1)
lymph node (mesenteric) (1)
mucles
oesophagus
ovary (2)
pancreas
prostate
salivary glands (mandibular,
parotid and sublingual gland)
skin
spleen
stomach
testicle (2)
thymus
thyroid (2) (incl. parathyroids)
tongue
trachea (incl. larynx)
urinary bladder
uterus (incl. cervix and oviducts)



HISTOPATHOLOGY: Yes
see gross pathology
Other examinations:
None
Statistics:
t-test used for statistical analysis of all parameters except organ weight (U-test)
Clinical signs:
no effects observed
Mortality:
no mortality observed
Body weight and weight changes:
no effects observed
Food consumption and compound intake (if feeding study):
not specified
Food efficiency:
not specified
Water consumption and compound intake (if drinking water study):
not specified
Ophthalmological findings:
not examined
Haematological findings:
no effects observed
Clinical biochemistry findings:
effects observed, treatment-related
Urinalysis findings:
no effects observed
Behaviour (functional findings):
not examined
Organ weight findings including organ / body weight ratios:
effects observed, treatment-related
Gross pathological findings:
no effects observed
Histopathological findings: non-neoplastic:
no effects observed
Histopathological findings: neoplastic:
no effects observed
Details on results:
The doses up to 1500 mg/kg body weight/day were tolerated by all animals without lethality. The body weight gain and total increase of body weights did not differ from the control group. Absolute and relative organ weights showed no significant changes in the substance groups compared to the control group, except the organ weight of the liver which is slightly increased for the males of group 4 (750/1500 mg/kg bw) and increased adrenal glands weight in high dose females. This result is considered of no relevance.

The pathological and histological evaluation did not show significant compound related gross or microscocopic organ injury of liver, kidneys, adrenals, heart, lung, spleen and gonads; dose dependent reversible local findings were restricted to the fore stomach mucosa (important hyperplasia and ulcerations, in some cases also hyper- and parakeratosis of the forestomach of males and females at the high dose. Similar effects but less intense at the medium and low doses). The biochemical parameters calcium, blood sugar, urea, creatinine, cholesterine, GGT, GOT, GPT and LDH did not show any critical signs. Only slight shifts which were not dose-dependent could be observed. These signs were considered as not substance depending.
Dose descriptor:
NOAEL
Effect level:
> 750 mg/kg bw/day (nominal)
Sex:
male/female
Basis for effect level:
other: No biologically relevant treatment-related effects observed on any of the parameters recorded at any dose, also test animals treated with 1500 mg/kg bw (Days 15-28) showed no adverse effect
Critical effects observed:
not specified

None

Conclusions:
Under the test conditions, the 28d NOAEL of amides, C12-18(even-numbered) and C18(unsatd.), N,N-bis(hydroxyethyl)to rats can therefore be considered to be greater than 750 mg/kg bw/d.
Executive summary:

A study was conducted to determine the oral toxicity of amides, C12-18 (even-numbered) and C18-unsatd., N,N-bis(hydroxyethyl) to rats after 28 d of exposure.

Groups of 10 male and 10 female rats were orally gavaged with the test substance diluted in olive oil 5 d/wk for 28 d. Clinical signs, bodyweight, hematology, clinical chemistry, urinalysis, gross and microscopic pathology were recorded. Additional groups of 5 male and 5 female rats were kept for a 4 month recovery period.

No treatment-related adverse effects were observed at any of the doses. Changes in the forestomach at some doses including controls were attributed to the use of olive oil and found to be reversible after end of exposure.

Under the test conditions, the 28d NOAEL of amides, C12-18(even-numbered) and C18-unsatd., N,N-bis(hydroxyethyl) to rats can therefore be considered to be greater than 750 mg/kg bw/d.

Endpoint conclusion
Dose descriptor:
NOAEL
750 mg/kg bw/day
Study duration:
subacute
Species:
rat
Quality of whole database:
Sufficient data available.

Repeated dose toxicity: dermal - systemic effects

Link to relevant study records
Reference
Endpoint:
sub-chronic toxicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Study period:
Not available
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study well documented, meets generally accepted scientific principles, acceptable for assessment
Justification for data waiving:
other:
Reason / purpose:
reference to same study
Reason / purpose:
reference to other study
Principles of method if other than guideline:
The test substance is applied daily to the skin in graduated doses to several groups of experimental animals, one dose per group, for a period of 14 wk. During the period of application the animals are observed daily to detect signs of toxicity. Animals which die during the test are necropsied, and at the conclusion of the test the surviving animals were sacrificed and necropsied.
GLP compliance:
yes
Limit test:
no
Species:
rat
Strain:
Fischer 344
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Taconic Farms, Germantown, NY
- Age at study initiation: 6 wk
- Housing: Housed individually in Polycarbonate cages (Lab Products, Inc., Maywood, NJ)
- Bedding: Sani-Chip heat-treated hardwood chips (P.J. Murphy Forest Products Corp., Montville, NJ)
- Diet : NIH-07 open formula pelleted diet (Zeigler Brothers, Inc., Gardners, PA), ad libitum
- Water : Tap water (Columbus municipal supply), ad libitum
- Acclimation period: 14 to 15 d

ENVIRONMENTAL CONDITIONS
- Temperature : 22.2 -23.9°C
- Humidity : 38-55 %
- Air changes : 10/hr
- Photoperiod : 12 h dark/12 h light

IN-LIFE DATES: From: Feb. 10, 1992 To: May 13, 1992

Type of coverage:
open
Vehicle:
ethanol
Details on exposure:
Not reported


Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
Periodic analyses of the dose formulations of test material were conducted at the study laboratory using HPLC. Dose formulations from the beginning, middle, and end of the studies were analysed.
Duration of treatment / exposure:
14 wk
Frequency of treatment:
5 exposures/wk
Remarks:
Doses / Concentrations:
0, 25, 50, 100, 200, or 400 mg/kg bw (0, 30, 61, 121, 243, or 485 mg/mL in ethanol)
Basis:
nominal per unit body weight
No. of animals per sex per dose:
10/sex/dose in the core study, 10/sex/dose for clinical pathology groups
Control animals:
yes, concurrent vehicle
Details on study design:
No information




Positive control:
Not applicable
Observations and examinations performed and frequency:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Twice daily


DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Weekly once


BODY WEIGHT: Yes
- Time schedule for examinations: Weighed initially, weekly, and at the end of the studies


HAEMATOLOGY: Yes
- Time schedule for collection of blood: On Days 4 and 24 (blood was collected from the retroorbital sinus of clinical pathology study male and
female rats from each dose group)
- Anaesthetic used for blood collection: Yes (carbon dioxide/oxygen mixture)
- How many animals: All animals
- Parameters checked in table [No.?] were examined.: Hematocrit; hemoglobin concentration; erythrocyte, reticulocyte, nucleated erythrocyte, and platelet counts; mean cell volume; mean cell hemoglobin; mean cell hemoglobin concentration; and leukocyte count and differentials


CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: On Days 4 and 24 (blood was collected from the retroorbital sinus of clinical pathology study male and
female rats from each dose group)
- How many animals: All animals
- Parameters checked in table [No.?] were examined: Urea nitrogen, creatinine, total protein, albumin, cholesterol, triglycerides, alanine aminotransferase, alkaline phosphatase, sorbitol dehydrogenase, and total bile acids


OTHER: Organs weighed were heart, right kidney, liver, lung, right testis, and thymus
Sacrifice and pathology:
SACRIFICE: At the end of the 14 wk studies, blood was collected from the retroorbital sinus of all core study rats for hematology and clinical chemistry analyses. Thereafter the test animals were anesthetised with a carbon dioxide/oxygen mixture.
GROSS PATHOLOGY: Yes
HISTOPATHOLOGY: Yes. Complete histopathology was performed on 0 and 400 mg/kg bw. In addition to gross lesions and tissue masses, the following tissues were examined: heart, large intestine (cecum, colon, rectum), small intestine (duodenum, jejunum, ileum), kidney, liver, lung, lymph nodes (mandibular and mesenteric), mammary gland, nose, ovary, pancreas, parathyroid gland, pituitary gland, preputial gland, prostate gland, salivary gland, spleen, stomach (forestomach and glandular), testis (and epididymis and seminal vesicle), thymus, thyroid gland, trachea, urinary bladder, and uterus. In addition, the skin (site of application) was examined in all core study animals, and the kidney was examined in core study male and female rats.
Other examinations:
Sperm motility and vaginal cytology: At the end of the studies, samples were collected for sperm motility or vaginal cytology from all rats receiving 100, 200 and 400 mg/kg bw of test material. The following sperm motility parameters were evaluated: spermatid heads per gram of testis, spermatid heads per testis, spermatid count, and epididymal spermatozoal motility and concentration. The left cauda epididymis, epididymis, and testis were weighed. Vaginal samples for cytology evaluations were collected for 12 consecutive days prior to the end of the studies from all female rats. The length of the estrous cycle and the length of time spent in each stage of the cycle were evaluated.
Statistics:
Not reported
Clinical signs:
effects observed, treatment-related
Dermal irritation:
effects observed, treatment-related
Mortality:
mortality observed, treatment-related
Body weight and weight changes:
effects observed, treatment-related
Food consumption and compound intake (if feeding study):
not examined
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
Clinical biochemistry findings:
effects observed, treatment-related
Urinalysis findings:
not examined
Behaviour (functional findings):
not examined
Organ weight findings including organ / body weight ratios:
effects observed, treatment-related
Gross pathological findings:
no effects observed
Histopathological findings: non-neoplastic:
effects observed, treatment-related
Histopathological findings: neoplastic:
not examined
Details on results:
CLINICAL SIGNS AND MORTALITY: Clinical findings included irritation of the skin at the site of application in 100, 200, and 400 mg/kg bw males and females.


BODY WEIGHT AND WEIGHT GAIN: Final mean body weights and body weight gains of 200 and 400 mg/kg bw males and females were significantly less than those of the vehicle controls.



HAEMATOLOGY: At week 14, a minimal microcytic, normochromic, nonresponsive anemia occurred in the 100 and 200 mg/kg bw females and 400 mg/kg bw males and females. The anemia also occurred in the 400 mg/kg bw males and females on Day 24. Increased segmented neutrophil counts occurred in 400 mg/kg bw males and females at week 14 and in 400 mg/kg bw females on Day 24.


CLINICAL CHEMISTRY: Cholesterol concentrations were significantly decreased in 200 and 400 mg/kg bw males and in females administered 100 mg/kg bw or greater; triglyceride concentrations were also decreased in 200 and 400 mg/kg bw males. At week 14, there was a minimal concentration-related increase of serum albumin concentration in all treated groups of females and in 100 mg/kg bw or greater male rats; on Day 24, increased albumin concentration occurred in the 400 mg/kg bw females. There were minimal increases of urea nitrogen concentration that occurred in the 200 and 400 mg/kg bw female rats on Day 24 and at week 14. At week 14, an increase in alanine aminotransferase activity occurred in 50 mg/kg bw or greater male rats. Additionally, alkaline phosphatase activity was increased in 400 mg/kg bw males.



ORGAN WEIGHTS: Kidney weights of females administered 50 mg/kg bw or greater were significantly greater than those of the vehicle control group. Left epididymis weights of 200 and 400 mg/kg bw males were significantly less than those of the vehicle controls, but this was most likely secondary to decreased mean body weights in these groups



HISTOPATHOLOGY: Histopathologic lesions of the skin at the site of application included epidermal hyperplasia, sebaceous gland hyperplasia, chronic active inflammation, parakeratosis, and ulcer. The incidences and severities of these skin lesions generally increased with increasing dose in males and females. The incidences of renal tubule regeneration in 100, 200, and 400 mg/kg bw females were significantly greater than the vehicle control incidence, and the severities in 200 and 400 mg/kg bw females were increased.


OTHER: Estrous cycle lengths of dosed females were similar to those of the vehicle controls

Dose descriptor:
NOAEL
Effect level:
ca. 50 mg/kg bw/day (nominal)
Sex:
male/female
Basis for effect level:
other: Overall effects
Critical effects observed:
not specified

None

Conclusions:
Under the test conditions, the No Observed Adverse Effect Level (NOAEL) of the test material was considered to be 50 mg/kg bw .
Executive summary:

A study was conducted to evaluate the subchronic toxic effects of amides, C8-18 and C18-unsatd., N,N-bis(hydroxyethyl) when administered by dermal route in F344/N rats. The study was performed in compliance with Food and Drug Administration Good Laboratory Practice Regulations (21 CFR, Part 58).

Groups of 10 male and 10 female rats were administered 0, 25, 50, 100, 200, or 400 mg/kg bw of amides, C8 -18 and C18 -unsatd., N, N-bis(hydroxyethyl) in ethanol by dermal application for 14 wk.

 

All rats survived until the end of the study. Final mean body weights and body weight gains of 200 and 400 mg/kg bw males and females were significantly less than those of the vehicle controls. Clinical findings included irritation of the skin at the site of application in 100, 200, and 400 mg/kg bw males and females. Hematological changes include minimal microcytic anemia at the end of the treatment period. Decreases in cholesterol and triglyceride concentrations were observed in the higher group rats.

Histopathological lesions of the skin at the site of application included epidermalhyperplasia, sebaceous gland hyperplasia, chronic active inflammation, parakeratosis, and ulcer. The incidences and severities of these skin lesions generally increased with increasing dose in males and females. The incidences of renal tubule regeneration in 100, 200, and 400 mg/kg bw females were significantly greater than the vehicle control incidence, and the severities in 200 and 400 mg/kg bwfemales were increased.

 

Under the test conditions, the No Observed Adverse Effect Level (NOAEL) of amides, C8 -18 and C18 -unsatd., N, N-bis(hydroxyethyl) was considered to be 50 mg/kg body weight.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
50 mg/kg bw/day
Study duration:
subchronic
Species:
rat
Quality of whole database:
Sufficient data available.

Additional information

Oral

A 28 day oral toxicity study conducted in rats with the structurally similar amides, C12-18 (even-numbered) and C18-unsatd., N,N-bis(hydroxyethyl) resulted in a NOAEL of > 750 mg/kg bw/day (male/female) since no treatment-related effects were noted in any of the parameters investigated at any of the dose levels tested (i.e. 70, 250 or 750 mg/kg bw/day). There were changes in the forestomach at some doses including controls, however the authors attributed this to the use of olive oil and found the forestomach changes to be reversible at the end of the exposure period (Potokar, 1983) .

In a 90 day oral toxicity study conducted in rats, the NOEL was determined to be 50 mg/kg bw/day for the structurally similar lauric acid diethanolamine condensate (LDEA, CAS No.120-40-1)based on growth retardation, biochemical changes and an increase in kidney weights seen in the 250 mg/kg bw/day dose group and growth retardation, haematological effects (anaemia) and increased kidney and liver weights at 500 and 1,000 mg/kg bw/day. The growth retardation (and possibly other effects) at 250 mg/kg bw/day and above was considered to be caused by the decrease in food intake due to the palatability of the diet (Gaunt IFet al., 1965).

Dermal

In a subchronic dermal toxicity study, 0, 25, 50, 100, 200 or 400 mg/kg bw of amides, C8-18 and C18-unsatd., N,N-bis(hydroxyethyl) administered in ethanol for 14 weeks to groups of 10 male and 10 female F344/N rats resulted in a NOAEL of 50 mg/kg bw/day. The NOAEL was established based on the significant decrease in mean body weight and body weight gain in the 200 and 400 mg/kg bw dose groups, skin irritation at the site of application in the 100, 200, and 400 mg/kg bw (males and females) dose groups, as well as haematological changes (minimal microcytic anaemia) and decreased cholesterol and triglyceride concentrations. Histopathological skin lesions at the site of application included epidermal hyperplasia, sebaceous gland hyperplasia, chronic active inflammation, parakeratosis and ulcer at 100 mg/kg bw and above (the incidences and severities of these skin lesions generally increased with increasing dose). Greater incidences of renal tubule regeneration in 100, 200 and 400 mg/kg bw females were also observed (NTP report 479, 2001).

In a subchronic dermal toxicity study, 0, 25, 50, 100, 200, 400 or 800 mg/kg bw/day of amides, C8-18 and C18-unsatd., N,N-bis(hydroxyethyl) administered for 14 weeks to groups of 10 male and 10 female B6C3F1 mice resulted in a NOAEL of 100 mg/kg bw/day. The NOAEL was established based on the incidence of chronic active inflammation at 200 mg/kg bw and above. The incidences and severities of these skin lesions generally increased with increasing dose. At 400 mg/kg bw/day, a significant increase in relative liver weight was noted in females and at 800 mg/kg bw/day, a significant increase in relative liver, kidney (males and females) and lung weights (females) occurred (NTP report 479, 2001).

Two years chronic dermal studies performed to assess the carcinogenic affects of amides, C8-18 and C18-unsatd., N,N-bis(hydroxyethyl) in rats and mice allowed derivations of NOAEL (rat) and LOAEL (mouse) as described in the following:

 

F344/N rats were administered doses of 0, 50 or 100 mg/kg bw of amides, C8-18 and C18-unsatd., N,N-bis(hydroxyethyl) (0, 85 or 170 mg/mL in ethanol), with 50 male and female animals in each group. Five exposures per week were given for 104 weeks. The animals were observed twice daily, body weights and clinical findings were recorded periodically. Necropsy and histopathology was performed on all animals. The survival rates of treated male and female rats were similar to those of the vehicle controls. The mean body weights of dosed males and females were similar to those of the vehicle controls throughout the study. The only treatment-related clinical finding was skin irritation at the site of application in the 100 mg/kg bw dose group (females). There were marginal increases in the incidences of renal tubule adenoma or carcinoma (combined) at 50 mg/kg bw (females). The severity of nephropathy increased with dose in female rats. Non-neoplastic lesions of the skin at the site of application included epidermal hyperplasia, sebaceous gland hyperplasia, parakeratosis, and hyperkeratosis, and the incidences and severities of these lesions increased with dose. The incidences of chronic active inflammation, epithelial hyperplasia and epithelial ulcer of the forestomach increased with dose in female rats, and the increases were significant in the 100 mg/kg bw group. A NOAEL of 50 mg/kg bw could be established based on skin irritation at the site of application at 100 mg/kg bw (females) and significant increases in the epithelial ulcer of the forestomach (NTP report 479, 2001).

 

B6C3F1 mice (50 males and female) were administered doses of 0, 100 or 200 mg/kg bw of the test substance (0, 50 or 100 mg/mL in ethanol). Five exposures per week were given for 104 to 105 weeks. The animals were observed twice daily, body weights and clinical findings were recorded periodically. Necropsy and complete histopathology was performed on all animals. Survival of dosed male and female mice was generally similar to that of the vehicle controls. Female Mean bodyweights of 100 mg/kg bw from Week 93 and 200 mg/kg bw from Week 77 were lower than those of the vehicle controls. The only clinical finding attributed to treatment was skin irritation at the site of application in males administered 200 mg/kg bw. The incidences of hepatic neoplasms (hepatocellularadenoma, hepatocellular carcinoma, and hepatoblastoma) were significantly increased in male and/or female mice. The incidences of eosinophilic foci in dosed groups of male mice were increased relative to that in the vehicle controls. The incidences of renal tubule adenoma and renal tubule adenoma or carcinoma (combined) were significantly increased in 200 mg/kg bw males. Several non-neoplastic lesions of the skin at the site of application were considered treatment-related. Incidences of epidermal hyperplasia, sebaceous gland hyperplasia, and hyperkeratosis were greater in all dosed groups of males and females than in the vehicle controls. The incidences of thyroid gland follicular cell hyperplasia in all treated males and females were significantly greater than those in the vehicle control groups. Therefore, a LOAEL of 100 mg/kg bw was established based on body weight changes and skin irritation at the site of application in the 200 mg/kg bw dose (females) and several non-neoplastic lesions at all dose levels (NTP report 479, 2001).

Justification for selection of repeated dose toxicity via oral route - systemic effects endpoint:
Based on the adopted read-across approach, the data on amides, C12-18(even-numbered) and C18(unsatd.), N-hydroxyethyl has been chosen for the endpoint selection.

Justification for selection of repeated dose toxicity dermal - systemic effects endpoint:
NTP study, good quality and sufficient to meet this endpoint.

Repeated dose toxicity: dermal - systemic effects (target organ) digestive: stomach; other: skin

Justification for classification or non-classification

Based on the NOAEL derived from a subacute study (750 mg/kg bw/day) in which no treatment-related effects were observed, subchronic dermal studies (50 mg/kg bw day in rats and 100 mg/kg bw/day in mice) in which renal tubule regeneration in rats and organ-weight changes in mice were observed, and chronic dermal studies in rats (NOAEL: 50 mg/kg bw/day ) and mice (LOAEL: 100 mg/kg bw/day), it can be concluded that amides, C8-18 and C18-unsatd., N,N-bis(hydroxyethyl) does not require classification for repeated dose toxicity according to EC (67/548/EEC) and CLP (EC 1272/2008) criteria.