Registration Dossier

Administrative data

Description of key information

Oral
The 90-day dietary administration of the read-across substance C12-18 TMAC to rats up to the level of 273 mg a.i./kg bw/day resulted in toxicologically significant effects at the highest dose of 273 mg a.i./kg bw/day. No such effects were demonstrated at the lowest dose of 22 mg a.i./kg bw/day. Therefore, the 'No Observed Effect Level' (NOEL) was considered to be 22 mg a.i./kg bw/day. The effects observed at the mid dose were considered to be minor, isolated effects associated with the reduced palatability of the test substance and were considered not to represent an adverse health effect. Therefore the "No Observed Adverse Effect Level" (NOAEL) should be regarded as 113 mg a.i./kg bw/day.
Dermal
In a 28-day study conducted in rabbits on C16 TMAC, local effects; mild to marked acanthosis, hyperkeratosis, and partial to extensive necrosis of the epidermis and hair follicles, were seen at the site of application, however no systemic treatment-related effects were observed. Under the conditions of the test, the NOAEL was established at 10 mg test substance/kg bw/day. However, due to some deficiencies in the study (reduced number of test animals per group and limited histopathology), the NOAEL of the 90-day oral study with C12-18 TMAC was used as the starting point to derive the dermal DNEL.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records
Reference
Endpoint:
sub-chronic toxicity: oral
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
From 29 October, 2001 to 18 June, 2002
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study was conducted according to the OECD guideline 408, EU Annex V method B.26 and EPA OPPTS 870.3100 as well as in compliance with GLP.
Reference:
Composition 0
Qualifier:
according to
Guideline:
OECD Guideline 408 (Repeated Dose 90-Day Oral Toxicity in Rodents)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method B.26 (Sub-Chronic Oral Toxicity Test: Repeated Dose 90-Day Oral Toxicity Study in Rodents)
Deviations:
no
Qualifier:
according to
Guideline:
EPA OPPTS 870.3100 (90-Day Oral Toxicity in Rodents)
Deviations:
no
GLP compliance:
yes
Test material information:
Composition 1
Species:
rat
Strain:
other: Sprague-Dawley, Crl:CD® (SD) IGS BR
Sex:
male/female
Details on test animals and environmental conditions:
- Source: Charles River (UK) limited, Margate, Kent
- Age at study initiation: 6 wk
- Weight at study initiation: Males: 141-183 g, females: 132-161 g
- Acclimation period: 14 d

ENVIRONMENTAL CONDITIONS
- Temperature: 21±2 °C
- Humidity: 55±15%
- Photoperiod (hrs dark / hrs light): 12 h/12 h
Route of administration:
oral: feed
Vehicle:
other: mixed with diet
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
Mean dietary admixture concentrations were within acceptable limits for the purpose of the study (Gas chromatography).
Duration of treatment / exposure:
90 d
Frequency of treatment:
Daily in feed
Remarks:
Doses / Concentrations:
0, 100, 500 and 2000 ppm (equivalent to 22, 113 and 273 mg/kg bw/d after correction for 35.5% purity); the highest dose of 2000 ppm was reduced to 1000 ppm from Day 29 onwards due to deterioration in health of treated animals at 2000 ppm.
Basis:
nominal in diet
No. of animals per sex per dose:
10 males and 10 females per dose
Control animals:
yes, plain diet
Details on study design:
- Post-exposure recovery period in satellite groups: None
Observations and examinations performed and frequency:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: once daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: once daily

BODY WEIGHT: Yes
- Time schedule for examinations: Day 0 (the day before start of treatment) and weekly thereafter

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Weekly throughout the study

FOOD EFFICIENCY: Yes

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): Yes
- Time schedule for examinations: daily for each cage group

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: Before start of treatment and before termination of treatment (during week 12)
- Dose groups that were examined: All

HAEMATOLOGY: Yes
- Time schedule for collection of blood: End of treatment (Day 90)

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: End of treatment (Day 90)

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: Day 0 (the day before start of treatment) and weekly thereafter
- Dose groups that were examined: All
- Battery of functions tested: Sensory activity
Sacrifice and pathology:
GROSS PATHOLOGY: Yes, all animals
HISTOPATHOLOGY: Yes, Macroscopic lesions, Adrenals, Aorta, Bone and bone marrow (femur including stifle joint), Bone and bone marrow (sternum), Brain (including cerebrum, cerebellum and pons), Cecum, Colon, Duodenum, Epididymides, Eyes, Gross lesions, Heart, ileum, Jejunum, Kidneys, Liver, Lungs (with bronchi), Lymph nodes (cervical and mesenteric), Mammary gland, Muscle (skeletal), Oesophagus, Ovaries, Pancreas, Pituitary gland, Prostate, Rectum, Salivary glands (submaxillary), Sciatic nerve, Seminal vesicles, Skin (hind limb), Spinal cord (cervical), Spleen, Stomach, Testes, Thymus, Thyroid/parathyroid, Tongue, Trachea, Urinary bladder, Uterus.
Statistics:
Data were processed to give group mean values and standard deviation where appropriate. Haematological, blood chemical, organ weight, weekly body weight gain and quantitative functional performance and sensory reactivity data were assessed for control and test substance treatment groups for dose response relationship by linear regression analysis, followed by one way analysis of variance (ANOVA) incorporating Levene's test for homogeneity of variance. Where variances were shown to be homogenous, pairwise comparisons were conducted using Dunnett's test. Where Levene's test showed unequal variances, the data were analysed using non-parametric methods: Kruskal-Wallis ANOVA and Mann-Whitney 'U' test.
Clinical signs:
no effects observed
Mortality:
no mortality observed
Body weight and weight changes:
effects observed, treatment-related
Food consumption and compound intake (if feeding study):
effects observed, treatment-related
Food efficiency:
effects observed, treatment-related
Water consumption and compound intake (if drinking water study):
no effects observed
Ophthalmological findings:
no effects observed
Haematological findings:
no effects observed
Clinical biochemistry findings:
no effects observed
Behaviour (functional findings):
effects observed, treatment-related
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
Details on results:
CLINICAL SIGNS AND MORTALITY: No mortality occurred during the study period.
Clinical signs - High dose animals developed clinical signs of toxicity from Day 7 onwards. These included hunched posture, pilo-erection, tiptoe gait, diarrhoea and red/brown staining of external body surface. Due to these effects, the dose level was reduced to 1000 ppm from Day 29 onwards. Clinical signs persisted following the reduction in dose level and included two incidents of pallor of extremities together with generalised fur loss. No clinically observable signs of toxicity were detected at the mid and the high doses.

Behavioural assessment: Detailed open-field observations conducted during the study confirmed the clinical signs of hunched posture, pilo-erection and tiptoe gait detected in high dose animals. No such effects were detected at the mid or low dose levels.

Functional performance test: No treatment-related changes were detected.

Sensory Reactivity Assessments: High dose females showed an increase in startle reflex parameters compared with controls. No such effects were detected for high dose males or for animals of either sex treated with the lower doses.

BODY WEIGHT AND WEIGHT GAIN: Reduced body weight gain was detected for high dose animals of either sex during the first five weeks of the study compared with controls. Mid dose males were similarly affected but this was confined to week 1 and 2 only. Body weight gain recovered following reduction in the dose level and was comparable with controls thereafter but terminal bodyweights for high dose animals and mid dose males remained lower than controls. No adverse effect on bodyweight gain was detected for 500 ppm females or for animals of either sex treated with the low dose.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Reduced food intake was observed in the high and mid dose animals throughout the study period compared with controls.

FOOD EFFICIENCY: Food efficiency was reduced over the first three weeks of the study but this was confined to the high dose group only. No adverse effect on dietary intake or food efficiency was detected at the low dose.

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): No appreciable intergroup differences were detected. High dose animals showed a reduced water intake on Day 6 of the study which recovered thereafter.

OPHTHALMOSCOPIC EXAMINATION: No treatment-related effects.

HAEMATOLOGY: No treatment-related effects.

CLINICAL CHEMISTRY: No treatment-related effects.

ORGAN WEIGHTS: No toxicologically important organ weight changes were detected. The reductions in absolute weight (including heart, kidneys, liver and thymus weight at the high dose and heart weight at the mid dose) and increases in relative weight (including high dose brain epididymides, kidneys, spleen, testes and ovaries weight), were all considered to be a result of reduced bodyweight development rather than test substance toxicity.

GROSS PATHOLOGY: No treatment-related macroscopic abnormalities.

HISTOPATHOLOGY: NON-NEOPLASTIC: Treatment-related changes were observed in the spleen and kidneys. Lower severities of pigment accumulation were observed in the spleen of high dose male rats but not for the females (p <0.05). A higher incidence of pigment accumulation was observed in the kidneys of the high and mid dose male rats. In both tissues the pigment reacted positively to Perl's staining technique and was considered to be haemosiderin.
Dose descriptor:
NOEL
Effect level:
22 mg/kg bw/day (actual dose received)
Based on:
act. ingr.
Sex:
male/female
Basis for effect level:
other: Effects observed at 113 and 273 mg/kg bw/d
Dose descriptor:
NOAEL
Effect level:
113 mg/kg bw/day (actual dose received)
Based on:
act. ingr.
Sex:
male/female
Basis for effect level:
other: Clinical signs of toxicity, reduced body weight gain, reduced food efficiency and microscopic changes in the spleen and kidneys of high dose animals.
Critical effects observed:
not specified
Conclusions:
Dietary administration of the test substance to rats for a period of 90 d at the level of up to 273 mg a.i./kg bw/day resulted in toxicologically significant effects at the high dose and marginal effects at the next lower dose of 113 mg a.i./kg bw/d. No such effects were demonstrated at the lowest dose of 22 mg/kg bw/day. Therefore, the 'No Observed Effect Level' (NOEL) was considered to be 22 mg a.i./kg bw/day.

The changes observed at the mid dose were considered to be minor, isolated effects associated with the reduced palatability of the test substance and were considered not to represent an adverse health effect. Hence, for the purposes of hazard evaluation, the "No Observed Adverse Effect Level" (NOAEL) should be regarded as 113 mg/kg bw/d.
Executive summary:

Sprague-Dawley rats were administered the read-across substance C12-18 TMAC (0, 100, 500 or 2,000 ppm, corresponding to 22, 113 and 273 mg a.i./kg bw/day) in the diet for 90 days according to OECD guidelines. The highest dose of 2,000 ppm was reduced to 1,000 ppm from Day 29 onwards due to deterioration in health of the test animals at 2,000 ppm. At the highest dose, the treatment-related findings were clinical signs of toxicity, reduced body weight gain and food efficiency, organ weight changes and microscopic changes in the spleen and kidneys. At the mid dose, reduced body weight gain (males) and reduced food consumption, reduced absolute heart weight and higher incidence of haemosiderin accumulation in the kidneys of males was observed. No treatment-related effects were observed at the lowest dose. Hence, the NOEL was considered to be 100 ppm (i.e., equivalent to 22 mg a.i./kg bw/day). The changes observed at 500 ppm were considered to be minor, isolated effects associated with the reduced palatability of the test substance and were considered not to represent an adverse health effect. The NOAEL was therefore 500 ppm (i.e., equivalent to 113 mg a.i./kg bw/days).

Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
NOAEL
113 mg/kg bw/day
Study duration:
subchronic
Species:
rat
Quality of whole database:
Both studies are conducted according to the OECD guideline as well as in compliance with GLP and have Klimisch score 1. The information requirements for this tonnage band is sufficiently met with the available data.

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

Link to relevant study records
Reference
Endpoint:
sub-chronic toxicity: dermal
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
1979
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
Read across study hence maximum reliability rating of 2 assigned according to ECHA guidance, study is well documented, meets generally accepted scientific principles, acceptable for assessment. However, few deficiencies were observed in the study such as tested with lesser number of animals (i.e., 10/group rather than 20/group as per guideline) and histoptahology of limited organs was performed.
Reference:
Composition 0
Principles of method if other than guideline:
A 28-day dermal study was conducted in rabbits to evaluate the repeated dose dermal toxicity of the test substance.

GLP compliance:
not specified
Limit test:
no
Test material information:
Composition 1
Species:
rabbit
Strain:
New Zealand White
Sex:
male/female
Type of coverage:
open
Vehicle:
water
Details on exposure:
TEST SITE
- Area of exposure:
- % coverage: 25% of the body surface area.
- Time intervals for shavings or clipplings: all rabbits was abraded with a clipper head prior to the start of each application

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Following the exposure period, the treated skin surface was cleaned with water


TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0 or 10 mg/kg bw/day
- Concentration (if solution): 0 or 0.5% aqueous solutions, respectively. The dosage volume was 2.0 ml/kg bw


USE OF RESTRAINERS FOR PREVENTING INGESTION: yes, The animals were restrained with collars during the exposure period
Analytical verification of doses or concentrations:
not specified
Duration of treatment / exposure:
6.5 to 7 hours
Frequency of treatment:
5 days/week for 4 wks
Remarks:
Doses / Concentrations:
0 or 10 mg/kg/day
Basis:
no data
No. of animals per sex per dose:
5 New Zealand albino rabbits/sex/group
Control animals:
yes, concurrent vehicle
Details on study design:
- Duration of observation period following administration: All rabbits were examined daily for clinical signs and mortality. Dermal irritation
readings were recorded daily. The animals were weighed weekly during the exposure period. Blood was collected for haematology measurements before initiation of dosing and prior to termination. Liver and kidneys were weighed at necropsy. A complete list of tissues
was collected for histopathological evaluation
- Frequency of observations and weighing: weekly
- Necropsy of survivors performed: yes
Observations and examinations performed and frequency:
CAGE SIDE OBSERVATIONS: Yes / No / No data
- Time schedule: twice daily

DERMAL IRRITATION (if dermal study): Yes
- Time schedule for examinations: Daily

BODY WEIGHT: Yes
- Time schedule for examinations: Weekly

HAEMATOLOGY: Yes
- Time schedule for collection of blood: Blood was collected for haematology measurements before initiation of dosing and prior to termination

OTHER:
Mortality : twice daily
Sacrifice and pathology:
GROSS PATHOLOGY: Yes
HISTOPATHOLOGY: Yes Liver and kidneys were weighed at necropsy. A complete list of tissues was collected for histopathological evaluation
Clinical signs:
no effects observed
Dermal irritation:
effects observed, treatment-related
Description (incidence and severity):
Treated areas of the skin that showed mild to marked acanthosis with active mitosis, hyperkeratosis, and partial to extensive necrosis of the epidermis and hair follicles, partly with encrustation and exudate
Mortality:
no mortality observed
Body weight and weight changes:
no effects observed
Haematological findings:
no effects observed
Organ weight findings including organ / body weight ratios:
no effects observed
Gross pathological findings:
no effects observed
Histopathological findings: non-neoplastic:
no effects observed
Details on results:
Two control group animals died during the study. Slight to moderate erythema was observed in all treated rabbits between days 4 and 8, but disappeared in 4 rabbits by day 17. Very slight to slight oedema was observed between days 6 and 12 in 4 rabbits and subsided by day 17. Two rabbits had intermittent slight oedema during week 4, and one rabbit developed oedema on day 20. No evidence of desquamation or leather-like skin was present in these animals. In the other rabbits, slight atonia occurred up to week 4 in 3 animals. Slight skin fissuring was observed in most of the rabbits but typically disappeared by the end of the study. There were no treatment-related effects on body weight, haematology, organ weight, gross necropsy findings or histopathology, except for treated areas of the skin that showed mild to marked acanthosis with active mitosis, hyperkeratosis, and partial to extensive necrosis of the epidermis and hair follicles, partly with encrustation and exudate.
Dose descriptor:
NOAEL
Effect level:
10 mg/kg bw/day
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: see 'Remark'
Critical effects observed:
not specified
Conclusions:
Under the conditions of the test, the 28 d acute dermal NOAEL of the test substance for male and female rabbits was found to be 10 mg/kg bw/day.
Executive summary:

A 28-day repeated dose dermal toxicity study on the read-across substance C16 TMAC was conducted in New Zealand albino rabbits (both sexes). The purity was not specified and the study included a lower than recommended number of animals (i.e., 10/group rather than 20/group as per guideline) and histopathology was performed only on limited organs. The test substance (0 and 10 mg test substance/kg bw/day) was applied to the shaved, intact skin of groups of 5 New Zealand albino rabbits/sex/group for 6.5 to 7 hours, 5 days/week for 4 weeks. Dermal irritation readings were recorded daily. The animals were weighed weekly during the exposure period. Blood was collected for haematology measurements before initiation of dosing and prior to termination. Liver and kidneys weights were recorded at necropsy and limited histopathology was conducted. There were no systemic treatment-related effects on body weights, haematology, organ weights, gross necropsy findings or histopathology. Treated areas of the skin showed mild to marked acanthosis with active mitosis, hyperkeratosis, and partial to extensive necrosis of the epidermis and hair follicles, partly with encrustation and exudate. Under the conditions of the test, the NOAEL for male and female rabbits was found to be 10 mg test substance/kg bw/day.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
10 mg/kg bw/day
Study duration:
subacute
Species:
rabbit
Quality of whole database:
One study available only. The information requirements for this tonnage band is sufficiently met with the available data.

Mode of Action Analysis / Human Relevance Framework

Additional information

Oral

A 28-day repeated dose toxicity study was conducted on the read-across substance C16 TMAC in rats according to OECD guideline 407. Groups of 10 male and female rats were administered 0, 30, 100 and 300 mg/kg bw/day test substance by oral gavage for 28 days. The test substance used was a 24-26% aqueous solution but it is not clear if the doses mentioned were corrected. There were no treatment-related changes at the 30 and 100 mg/kg bw/day. In the high-dose group there was an increase in water consumption, changes in the absolute and relative weights of the adrenals and spleens (in males) without corresponding effects on haematology, clinical chemistry and histology. The forestomach of the high-dose group showed few microscopic changes, however animals in the high-dose recovery group showed a complete and regular regeneration of the forestomach mucosa. Hence, the forestomach effects were considered to be due to the irritating properties of the test substance rather than symptoms of systemic toxicity. The NOAEL for systemic effects was 300 mg/kg bw/day (Potokar M, 1991).

Sprague-Dawley rats were administered the read-across substance C12-18 TMAC (0, 100, 500 or 2,000 ppm, corresponding to 22, 113 and 273 mg a.i./kg bw/day) in the diet for 90 days according to OECD guidelines. The highest dose of 2,000 ppm was reduced to 1,000 ppm from Day 29 onwards due to deterioration in health of the test animals at 2,000 ppm. At the highest dose, the treatment-related findings were clinical signs of toxicity, reduced body weight gain and food efficiency, organ weight changes and microscopic changes in the spleen and kidneys. At the mid dose, reduced body weight gain (males) and reduced food consumption, reduced absolute heart weight and higher incidence of haemosiderin accumulation in the kidneys of males was observed. No treatment-related effects were observed at the lowest dose. Hence, the NOEL was considered to be 100 ppm (i.e., equivalent to 22 mg a.i./kg bw/day). The changes observed at 500 ppm were considered to be minor, isolated effects associated with the reduced palatability of the test substance and were considered not to represent an adverse health effect. The NOAEL was therefore 500 ppm (i.e., equivalent to 113 mg a.i./kg bw/days) (Jones et al., 2002).

Dermal

A 28-day repeated dose dermal toxicity study on the read-across substance C16 TMAC was conducted in New Zealand albino rabbits (both sexes). The purity was not specified and the study included a lower than recommended number of animals (i.e., 10/group rather than 20/group as per guideline) and histopathology was performed only on limited organs. The test substance (0 and 10 mg test substance/kg bw/day) was applied to the shaved, intact skin of groups of 5 New Zealand albino rabbits/sex/group for 6.5 to 7 hours, 5 days/week for 4 weeks. Dermal irritation readings were recorded daily. The animals were weighed weekly during the exposure period. Blood was collected for haematology measurements before initiation of dosing and prior to termination. Liver and kidneys weights were recorded at necropsy and limited histopathology was conducted. There were no systemic treatment-related effects on body weights, haematology, organ weights, gross necropsy findings or histopathology. Treated areas of the skin showed mild to marked acanthosis with active mitosis, hyperkeratosis, and partial to extensive necrosis of the epidermis and hair follicles, partly with encrustation and exudate. Under the conditions of the test, the NOAEL for male and female rabbits was found to be 10 mg test substance/kg bw/day (Spicer EJF, 1979).


Justification for selection of repeated dose toxicity via oral route - systemic effects endpoint:
90-day study is more robust and of longer duration study compared to 28-day study; the NOAEL of 90-day study is also more conservative.

Justification for selection of repeated dose toxicity inhalation - systemic effects endpoint:
The substance is a solid with a low vapour pressure. Due to its physical state and physical chemical properties it is unlikely that this substance will form inhalable dust, mist or fumes during normal processing and use conditions. In case inhalable forms of the substance are created under particular conditions (e. g. spraying, elevated temperature/pressure), appropriate risk management measures such as closed systems, exhaust ventilation or wearing of respirators are implemented to control exposure. Under such conditions, the risk to humans following inhalation exposure can be considered minimal and further testing involving vertebrate animals may be omitted, in accordance with Annex XI (1.2) of the REACH regulation.

Justification for selection of repeated dose toxicity inhalation - local effects endpoint:
The substance is a solid with a low vapour pressure. Due to its physical state and physical chemical properties it is unlikely that this substance will form inhalable dust, mist or fumes during normal processing and use conditions. In case inhalable forms of the substance are created under particular conditions (e. g. spraying, elevated temperature/pressure), appropriate risk management measures such as closed systems, exhaust ventilation or wearing of respirators are implemented to control exposure. Under such conditions, the risk to humans following inhalation exposure can be considered minimal and further testing involving vertebrate animals may be omitted, in accordance with Annex XI (1.2) of the REACH regulation.

Justification for selection of repeated dose toxicity dermal - systemic effects endpoint:
Only one study available. The purity was not specified and the study included a lower number of animals (i.e., 10/group rather than 20/group as per guideline) and histopathology of only limited organs was performed.

Repeated dose toxicity: via oral route - systemic effects (target organ) cardiovascular / hematological: spleen; urogenital: kidneys

Justification for classification or non-classification

Based on the observed effects and available NOAELs, it can be concluded that C12 -14 ADMAES does not require classification according Directive 67/548/EEC and Regulation EC 1272/2008 criteria.