Registration Dossier

Administrative data

Description of key information

Based on the results of a 90-day study with the read across substance, Coco TMAC in rats, the NOAEL of 113 mg a.i./kg bw/day has been considered further for the hazard assessment of Oleyl TMAC. Overall, the available studies with read across substance, Coco TMAC and DDAC in different species, all revealed NOAELs based on reduction in body weight and body weight gain, consistent with decreased food consumption. All effects could be therefore be attributed to local gastrointestinal irritation/corrosion and consequent reduced food intake without observing any primary systemic effect. Therefore, the derivation of a DNEL for systemic effects was deemed inappropriate.

With regard to the dermal route, due to some deficiencies in the available 28-day dermal study with read across substance, C16 TMAC (reduced number of test animals per group and limited histopathology), the 90-day oral study with read across substance can be considered for the systemic hazard assessment of Oleyl TMAC.

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:
read-across based on grouping of substances (category approach)
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:
guideline study
Remarks:
KL2 due to RA
Justification for type of information:
Refer to the Quaternary ammonium salts (QAS) category or section 13 of IUCLID for details on the category justification. The study with the read across substance is considered sufficient to fulfil the information requirements as further explained in the provided endpoint summary.
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
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 days
Frequency of treatment:
Daily in feed
Remarks:
Doses / Concentrations:
0, 100, 500 and 2,000 ppm (i.e., equivalent to 22, 113 and 273 mg/kg bw/day after correction for 35.5% purity); the highest dose of 2,000 ppm was reduced to 1,000 ppm from Day 29 onwards due to deterioration in health of treated animals at 2,000 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.
Haemosiderin is normally observed in kidneys of aged rats, where it accumulates in tubular epithelium. There are no indications of bleeding (black faeces, increase spleen weight, accelerated erythropoiesis).
Key result
Dose descriptor:
NOAEL
Effect level:
ca. 40 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 occurence of haemosiderine in kidneys of high dose animals.
Remarks on result:
other: reduction of body weight and food consumption can be considered secondary compared to the corrosive properties of the test substance; Haemosiderin is normally observed in kidneys of aged rats, where it accumulates in tubular epithelium.
Key result
Critical effects observed:
no

The high dose showed clear effects related to palatability (esp. low food intake first week, clear increase after lowering dose level, lower BW gain), and clinical signs of discomfort starting after about 2 weeks leading to hunched posture of all animals, and red/brown staining of fur and piloerection in most day. This improved a little with lowering of dose. No specific toxicity was observed in haematology and clinical chemistry, terminal necropsy (besides stained fur in half of the animals and irritation stomach in one female), and organ weight (high dose are affected in a pattern consistent with lower BW, not considered indicative for organ toxicity). Histopathology only reported possible treatment related effects of haemosiderin accumulation in spleen and kidney. Generally, increased deposition of haemosiderin is followed from haemolytic effects.

Typically in cases of haemolytic anaemia higher grades of severity for both splenic extramedullary haemopoiesis and for splenic haemosiderin accumulation would be expected and this is often associated with accumulations of haemosiderin in the renal tubules. However, haemosiderin does not usually appear in excess in the renal tubules until a threshold increase in the spleen has been exceeded.

In this case, there was no evidence of increased haemolysis from the blood haematology parameters, and also no indication for an increased extramedullary haemopoiesis. Additionally, there was no Kupffer cell hemosiderin pigmentation of the liver. Haemosiderin is normally observed in kidneys of aged rats, where it accumulates in tubular epithelium. However, there are no indications of bleeding (black faeces, increase spleen weight, accelerated erythropoiesis). Other study parameters essentially did not show treatment-related effects. Also, as far as it is known, for haemosiderin deposition no significant difference is generally seen between males and females.

So in this case, there was no indication of extramedullary haemopoiesis, no effects in blood haematology, and if anything, the haemosiderin deposition seemed to decrease with dose in both males and females. In view that all reported levels are only minimal or incidental slight, levels in the males remain below levels in female, and normally there is no difference between male and females, it can be concluded that the reported statistical difference between control and dosed groups in the males are of no toxicological relevance. Therefore, in line with the study authors the NOAEL can be established at 500 ppm (i.e., equivalent to 40 mg a.i./kg bw/day).

Conclusions:
Based on the results of the read across study, a similar NOAEL of 40.3 mg/kg bw/day can be considered for the test substance, Oleyl TMAC.
Executive summary:

A 90-day study was conducted to determine the oral repeated dose toxicity of the read across substance, Coco TMAC (active: 35.5%), according to OECD Guideline 408 and EU Method B.26, in compliance with GLP. Sprague-Dawley rats were administered the test substance at concentrations of 0, 100, 500 or 2000 ppm (i.e., corresponding to 0, 22, 113 and 273 mg/kg bw/day in males and 0, 25, 121, 297 mg/kg bw/day in females) in the diet for 90 d. The active ingredient dose equivalent were calculated to be 0, 7.9, 40.3 and 96.9 mg a.i./kg bw/day in males and 8.8, 42.9, 105.3 mg a.i./kg bw/day in females. The highest dose of 2000 ppm was reduced to 1000 ppm from Day 29 onwards due to deterioration in health of the test animals at 2000 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. Based on the results of the study, dietary administration of the test substance to rats for a period of 90 d at levels up to 273 mg/kg bw/day resulted in toxicologically significant effects at the high dose and marginal effects at the next lower dose of 113 mg/kg bw/day (500 ppm). No such effects were demonstrated at the lowest dose of 22 mg/kg bw/day (100 ppm).The changes observed at the mid dose (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. Therefore, based on effects on body weight, food efficiency and clinical signs the study authors established the NOAEL at the mid-dose level of 500 ppm (i.e., equivalent to 40.3 mg ai./kg bw/day) (Jones, 2002).The accumulation of haemosiderin in the spleen and kidneys at high and mid doses can be considered questionable for their toxicological relevance as they were not associated with any signs of bleeding (black faeces, increased spleen weight, accelerated erythropoiesis) and occurred in the absence of any effects on haematological parameters. Also, their levels in the males remained below the levels in female, whereas typically there is no known difference between the sex of animals for this effect. Further, the reduction in body weight and body weight gain, was attributed to local gastrointestinal irritation/corrosion and consequent reduced food intake without observing any primary systemic effect.

Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
NOAEL
113 mg/kg bw/day
Study duration:
subchronic
Species:
rat
Quality of whole database:
The information requirements for this tonnage band is sufficiently met with the available data.

Repeated dose toxicity: inhalation - systemic effects

Link to relevant study records
Reference
Endpoint:
short-term repeated dose toxicity: inhalation
Data waiving:
study scientifically not necessary / other information available
Justification for data waiving:
other:
Reason / purpose:
data waiving: supporting information
Reason / purpose:
data waiving: supporting information
Critical effects observed:
not specified
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:
read-across based on grouping of substances (category approach)
Adequacy of study:
key study
Study period:
1979
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment
Remarks:
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.
Justification for type of information:
Refer to the Quaternary ammonium salts (QAS) category or section 13 of IUCLID for details on the category justification. The study with the read across substance is considered sufficient to fulfil the information requirements as further explained in the provided endpoint summary.
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 410 (Repeated Dose Dermal Toxicity: 21/28-Day Study)
GLP compliance:
not specified
Limit test:
no
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
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:
no effects observed
Clinical biochemistry findings:
not examined
Urinalysis findings:
not examined
Behaviour (functional findings):
not examined
Immunological findings:
not examined
Organ weight findings including organ / body weight ratios:
no effects observed
Gross pathological findings:
no effects observed
Neuropathological findings:
not examined
Histopathological findings: non-neoplastic:
no effects observed
Histopathological findings: neoplastic:
not examined
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.
Key result
Dose descriptor:
NOAEL
Effect level:
10 mg/kg bw/day
Based on:
test mat.
Sex:
male/female
Basis for effect level:
dermal irritation
other: see 'Remark'
Key result
Critical effects observed:
no
Conclusions:
Based on the results of the read across study, the NOAEL for Oleyl TMAC can be considered to be 10 mg/kg bw/day.
Executive summary:

A 28-day study was conducted to determine the repeated dose dermal toxicity of the read across substance, C16 TMAC, in New Zealand albino rabbits (both sexes) according to a method similar to OECD Guideline 410. 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 study, the 28d NOAEL for male and female rabbits was found to be 10 mg/kg bw/day (males/females) (Spicer, 1979). Based on the results of the read across study, a similar NOAEL can be considered for Oleyl TMAC.


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:
The information requirements for this tonnage band is sufficiently met with the available data. However, due to some deficiencies in the 28-day dermal study with read across substance, C16 TMAC, the NOAEL of the 90-day oral study with Coco TMAC has been used as the starting point for hazard assessment.

Repeated dose toxicity: dermal - local effects

Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Study duration:
subacute
Species:
rabbit
Quality of whole database:
The test substance has been classified as corrosive (no threshold derived)

Additional information

Oral:

A 90-day study was conducted to determine the oral repeated dose toxicity of the read across substance, Coco TMAC (active: 35.5%), according to OECD Guideline 408 and EU Method B.26, in compliance with GLP. Sprague-Dawley rats were administered the test substance at concentrations of 0, 100, 500 or 2000 ppm (i.e., corresponding to 0, 22, 113 and 273 mg/kg bw/day in males and 0, 25, 121, 297 mg/kg bw/day in females) in the diet for 90 d. The active ingredient dose equivalent were calculated to be 0, 7.9, 40.3 and 96.9 mg a.i./kg bw/day in males and 8.8, 42.9, 105.3 mg a.i./kg bw/day in females. The highest dose of 2000 ppm was reduced to 1000 ppm from Day 29 onwards due to deterioration in health of the test animals at 2000 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. Based on the results of the study, dietary administration of the test substance to rats for a period of 90 d at levels up to 273 mg/kg bw/day resulted in toxicologically significant effects at the high dose and marginal effects at the next lower dose of 113 mg/kg bw/day (500 ppm). No such effects were demonstrated at the lowest dose of 22 mg/kg bw/day (100 ppm).The changes observed at the mid dose (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. Therefore, based on effects on body weight, food efficiency and clinical signs the study authors established the NOAEL at the mid-dose level of 500 ppm (i.e., equivalent to 40.3 mg ai./kg bw/day) (Jones, 2002).The accumulation of haemosiderin in the spleen and kidneys at high and mid doses can be considered questionable for their toxicological relevance as they were not associated with any signs of bleeding (black faeces, increased spleen weight, accelerated erythropoiesis) and occurred in the absence of any effects on haematological parameters. Also, their levels in the males remained below the levels in female, whereas typically there is no known difference between the sex of animals for this effect. Further, the reduction in body weight and body weight gain, was attributed to local gastrointestinal irritation/corrosion and consequent reduced food intake without observing any primary systemic effect.

As per the Biocides assessment report on Coco TMAC, which was published by the Italian authorities in April 2016, similar results were obtained from subchronic feeding study with the read across substance, DDAC in rats where the critical effect upon oral exposure was identified as decreased body weight gain, leading to a NOAEL of 42 mg/kg bw/day. Further, results from dog studies with DDAC do not indicate species difference towards this mechanism of toxicity by quaternary ammonium compounds. The 90-day dog study with DDAC resulted in a NOAEL of 15 mg ai./kg bw/day, the highest tested dose (ECHA biocides assessment report, 2016).

Overall, considering that the available studies with read across substances, Coco TMAC and DDAC, in different species, all revealed NOAELs based on reduction in body weight and body weight gain, consistent with decreased food consumption, the effects could be attributed to local gastrointestinal irritation/corrosion and consequent reduced food intake without primary systemic effect. Therefore, the derivation of a DNEL for systemic effects was deemed inappropriate (ECHA biocides assessment report, 2016).

Dermal

A 28-day study was conducted to determine the repeated dose dermal toxicity of the read across substance, C16 TMAC, in New Zealand albino rabbits (both sexes) according to a method similar to OECD Guideline 410. 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 study, the 28d NOAEL for male and female rabbits was found to be 10 mg/kg bw/day (males/females) (Spicer, 1979). Based on the results of the read across study, a similar NOAEL can be considered for Oleyl TMAC.

Inhalation

The substance is a solid with a low vapour pressure, which forms clumps at room temperature. Due to it physical state and physico- chemical properties, it is unlikely that it will form inhalable dust, mist or fumes when handled and used in solid form. In case inhalable forms of the substance (either pure or in aqueous solutions) 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. Nevertheless, the risk assessment for this route has been carried out based on oral studies available with the read across substance, using appropriate route-to-route extrapolation assessment factors as per the ECHA Guidance R.8.

Justification for classification or non-classification

Based on the observed effects and available NOAELs in 90-day oral study as well as 28-day dermal study with read across substances, it can be concluded that Oleyl TMAC does not warrant classification for STOT RE according to EU CLP criteria (Regulation 1272/2008/EC).​