Didecyldimethylammonium chloride

Endpoint summary

Key value for chemical safety assessment

Toxic effect type:

concentration-driven

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Reference 1

Endpoint:

chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

14 Nov, 2003 - 13 Mar, 2008

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

The study was performed in accordance with the OECD and OPPTS protocols, although there were few subsequent amendments, with the following deviations from the agreed Study plan: - the temperature and relative humidity recorded in the animal room were sometimes out of the target ranges specified in the Study plan, - on day 47, animals were checked for mortality or signs of morbidity only once, instead of at least twice as stated in the Study plan, - in order to decrease cross-contamination risks, the racks were no longer rotated around the room from day 280, - I. Gaou took on the responsibility of this study from 19 October 2004, instead of 18 November 2003 as specified by error in her statement, - further to the receipt of a new certificate of analysis, the test substance contained 39.6% DDAC instead of 40.5%, - the concentration of preparations was additionally checked in week 104. These deviations were not considered to have compromised the validity or integrity of the study.

Qualifier:

according to guideline

Guideline:

OECD Guideline 453 (Combined Chronic Toxicity / Carcinogenicity Studies)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: US EPA guideline OPPTS 870.3700, August 1998

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

Dietary admixture

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The analysis of mean achieved dose levels were performed at regular intervals.

Duration of treatment / exposure:

52 weeks for toxicology group and 104 weeks for carcinogenicity group.

Frequency of treatment:

Daily

Remarks:

Doses / Concentrations:
15.6, 32.6 and 66.1 mg a.i./kg bw/day for males and 18.2, 39.2 and 77.2 mg a.i./kg bw/day for females (52 weeks)
Basis:
nominal in diet

Remarks:

Doses / Concentrations:
12.6, 27.3 and 55.4 mg a.i./kg bw/day for males and 15.7, 33.8 and 69.5 mg a.i./kg bw/day for females (104 weeks)
Basis:
nominal in diet

No. of animals per sex per dose:

Three groups of 70 male and 70 female rats in total. Twenty males and 20 females in each group were used for toxicological investigations and treated for 52 weeks. Fifty males and 50 females in each group were used to investigate the carcinogenic potential. One additional group of 60 male and 60 female rats received untreated diet under the same experimental conditions and acted as a toxicology control group (10 males and 10 females) and as a carcinogenicity control group (50 males and 50 females).

Control animals:

yes, concurrent vehicle

Details on study design:

Three groups of 70 male and 70 female rats were treated with the test substance containing 39.6% of the active substance DDAC (didecyldimethylammonium chloride) by daily oral administration (dietary admixtures) at the constant concentrations of 700, 1500 or 3000 ppm (corresponding to 277.2, 594 or 1188 ppm of DDAC). The dietary admixtures were supplied ad libitum. Twenty males and 20 females in each group were used for toxicological investigations and treated for 52 weeks. Fifty males and 50 females in each group were used to investigate the carcinogenic potential and were treated for 104 weeks. One additional group of 60 male and 60 female rats received untreated diet under the same experimental conditions and acted as a toxicology control group (10 males and 10 females) and as a carcinogenicity control group (50 males and 50 females).

Positive control:

Not applicable

Observations and examinations performed and frequency:

The animals were checked at least once a day for mortality and twice daily for clinical signs. In addition, detailed clinical examinations were made once a week. After 6 months of treatment, all animals were palpated every 2 weeks in order to record the time of onset, location, size, appearance and progression of palpable masses. Body weights were recorded once during the pre-treatment period, on the first day of treatment, once a week during the first 13 weeks of the treatment period and then once every 4 weeks until the end of the study. Food consumption was recorded once a week during the first 13 weeks of the study, once every 3 months between weeks 14 and 26, once a month between weeks 27 and 39 and then every 4 weeks until the end of the study. Hematology, blood biochemistry and urinalysis investigations were performed on all surviving animals allocated to toxicology sub-groups in weeks 13, 26 and 51. The differential white cell count was determined for all surviving control animals and those treated at 3000 ppm in weeks 52, 78 and 104.

Sacrifice and pathology:

Surviving toxicology sub-group animals were killed at the end of the 52-week treatment period and carcinogenicity sub-group animals were killed at the end of the 104-week treatment period. A full macroscopic post-mortem examination was performed on all the animals. Designated organs were weighed and selected tissue specimens preserved. A microscopic examination was performed on all masses, and on designated tissues from control animals and those treated at 3000 ppm of the test substance sacrificed at the end of the 52 or 104-week treatment periods, and from animals that died prematurely.

Other examinations:

None

Statistics:

Analysis of survival data - Kaplan Meier technique and Peto's method.
Analysis of tumor incidence: Peto's method, one-tailed exact test and Armitage's 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):

no effects observed

Food efficiency:

no effects observed

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

no effects observed

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Histopathological findings: neoplastic:

no effects observed

Details on results:

Mortality/Survival rate: No effects.
Clinical signs: No effects 
Macroscopic investigations: No effects
Haematology: No effects 
Clinical Chemistry: No effects 
Urinalysis: No effects 
Pathology: Toxicity groups (52 weeks) There was an increase in incidence of reduced size in the thymus of females in all treated groups, which correlated with an (non-significant) increase in lymphoid atrophy at microscopic examination. The organ weights were not significantly affected. This may to be due to an unusually low incidence in the control group, however a treatment-related effect cannot be excluded. There were no other treatment-related findings. All other necropsy findings were typical of animals of this strain and age.
Carcinogenicity groups (104 weeks): No effects
Organ Weights: No effects 
Histopathology: Neoplastic findings: No effects;
Non-neoplastic findings for toxicity groups (52 weeks) The following statistically significant treatment-related findings were present:
- mesenteric lymph node: increase in hemorrhage in high-dose males
- peyer's patches: decrease in germinal centers in high-dose females. There were no other treatment-related findings
Non-neoplastic findings for carcinogenicity groups (104 weeks) The following statistically significant treatment-related findings were present:
Mesenteric lymph node: 
- increase in histiocytosis in high-dose females
- increase in mastocytosis in high-dose males and females
Peyer's patches: 
- decrease in germinal centres in high-dose males and females. There were no other treatment-related findings.

Key result

Dose descriptor:

LOAEL

Effect level:

ca. 55.4 mg/kg bw/day (actual dose received)

Based on:

act. ingr.

Sex:

male

Basis for effect level:

body weight and weight gain

Key result

Dose descriptor:

NOAEL

Effect level:

ca. 27.3 mg/kg bw/day (actual dose received)

Based on:

act. ingr.

Sex:

male

Basis for effect level:

body weight and weight gain

Key result

Dose descriptor:

LOAEL

Effect level:

ca. 69.5 mg/kg bw/day (actual dose received)

Based on:

act. ingr.

Sex:

female

Basis for effect level:

body weight and weight gain

Key result

Dose descriptor:

NOAEL

Effect level:

ca. 33.8 mg/kg bw/day (actual dose received)

Based on:

act. ingr.

Sex:

female

Basis for effect level:

body weight and weight gain

Key result

Dose descriptor:

LOAEL

Effect level:

ca. 62 mg/kg bw/day (actual dose received)

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

body weight and weight gain

Key result

Dose descriptor:

NOAEL

Effect level:

ca. 31 mg/kg bw/day (actual dose received)

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

body weight and weight gain

Key result

Critical effects observed:

not specified

Conclusions:

Based on the results, the LOAEL for toxicity was considered to be 3000 ppm and the NOAEL 1500 ppm (equivalent to 31 mg a.i./kg bw/day, combined males/females). The test substance was not found to be carcinogenic under the conditions of this study.

Executive summary:

A study was conducted in accordance with OECD Guideline 453 and OPPTS Guideline 870.3700 to evaluate the chronic toxicity of the test substance (40% a.i.). The test substance was administered daily to Sprague-Dawley rats by dietary admixture at the concentrations of 700, 1500, and 3000 ppm of for 52 weeks (toxicology sub-group) or for 104 weeks. The test substance did not induce any treatment-related mortality or clinical signs when administered daily for 52 or 104 weeks. At 3000 ppm, the mean body weight and mean body weight gain of the carcinogenicity subgroup animals were slightly lower than in controls (-26%), correlating in females with slightly lower mean food consumption during the first 13 weeks. There were no significant differences in hematological, biochemical and/or urinalysis parameters at any treated dose-level for animals of either sub-group, compared with controls. There were no macroscopic findings attributable to the test item at any of the tested dose-levels. The non-neoplastic histopathological findings confined to the mesenteric lymph nodes and Peyer’s patches were consistent with the continued action of a mild irritant and are considered to be of limited toxicological significance. There were no treatment-related neoplastic findings at histologic al examination. Consequently, the LOAEL for toxicity was considered to be 3000 ppm (equivalent to 62 mg/kg bw/day combined male/female) and the NOAEL 1500 ppm (equivalent to 31 mg a.i./kg bw/day, combined male/female). The test substance was not found to be carcinogenic under the conditions of this study (CIT, 2008).  

Reference 2

Endpoint:

short-term repeated dose toxicity: oral

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 409 (Repeated Dose 90-Day Oral Toxicity Study in Non-Rodents)

GLP compliance:

yes (incl. QA statement)

Species:

dog

Strain:

Beagle

Sex:

male/female

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

The test item was admixed in diet.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The concentration of the test item in the diet was constant throughout the study.

Duration of treatment / exposure:

4-week

Frequency of treatment:

Daily

Remarks:

Doses / Concentrations:
500, 1000 or 2000 ppm of test substance, with 40% a.i. (i.e., equivalent to 202.5, 405 and 810 ppm a.i.)
Basis:
nominal in diet

Remarks:

Doses / Concentrations:
7, 14 and 24 mg a.i./kg bw/day in males and 8, 13 and 23 mg a.i./kg bw/day
Basis:
actual ingested

No. of animals per sex per dose:

Two males and two females per group

Control animals:

yes, concurrent vehicle

Details on study design:

Three groups of two male and two female beagle dogs were treated with the test item by oral administration (dietary admixture) at the concentration of 500, 1000 or 2000 ppm of the test substance (corresponding to 202.5, 405 and 810 ppm of DDAC) for 4 weeks. An additional group of two males and two females received untreated diet alone under the same experimental conditions and acted as a control group.

Positive control:

ot applicable

Observations and examinations performed and frequency:

The animals were checked daily for mortality and clinical signs. Body weight was recorded weekly and food consumption was measured daily during the predose period and throughout the treatment period. Achieved dosage was calculated daily. Hematological and blood biochemical investigations were performed before the beginning and at the end of the treatment period.

Sacrifice and pathology:

On completion of the treatment period, the animals were killed and submitted to a full macroscopic examination. Designated organs were weighed and tissue specimens were preserved. A microscopic examination was performed on selected tissues from animals in the control and high-dose groups.

Other examinations:

None

Statistics:

No data

Clinical signs:

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):

effects observed, treatment-related

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:

no effects observed

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

not examined

Details on results:

Mortality: No unscheduled death occurred during the study.
Clinical signs: Emaciated appearance, corresponding to decreased body weight/body weight loss and lower food consumption, was noted in one male and one female given 2000 ppm of the test substance (corresponding to 810 ppm of DDAC).
Body weight: When compared to controls, lower body weight gain was noted in males given 2000 ppm of the test substance (corresponding to 810 ppm of DDAC), and body weight loss was noted in females of the same dose-group.
Food consumption:  Lower mean food consumption was noted throughout the study in animals given 2000 ppm of the test substance.
Achieved dosage: The mean achieved dosage remained quite stable throughout the study in all groups. It increased in a dose proportional manner, except on a few occasions in animals given 2000 ppm of the test substance, as their food consumption was lower than other treated animals. The mean achieved dosages of DDAC for the dose-levels of 500, 1000 and 2000 ppm of the test substance were as follows: - males: 7, 14 and 24 mg/kg/day of DDAC, respectively, - females: 8, 13 and 23 mg/kg/day of DDAC, respectively.
Hematology and blood biochemistry: No relevant changes were noted in any laboratory parameter of the treated animals.
Organ weights: No treatment-related effect on organ weights was noted.
Macroscopic post-mortem examination: No treatment-related necropsy findings were noted.
Microscopic examination: No treatment-related histopathological findings were noted.

Key result

Dose descriptor:

NOAEL

Effect level:

> 2 000 ppm

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: (i.e., equivalent to > 23 mg a.i./kg bw/day)

Key result

Critical effects observed:

not specified

None

Conclusions:

Under the study conditions, the NOAEL was probably higher than 2000 ppm (i.e. 24 and 23 mg a.i./kg bw/day in males and females, respectively).

Executive summary:

A study was conducted to determine the toxicity of the test substance (40% a.i.) administered by dietary admixture to Beagle dogs for 4 weeks at concentrations of 500, 1000 and 2000 ppm (i.e. 202.5, 405 and 810 ppm a.i.) in accordance with OECD Guideline 409. The animals were checked daily for mortality and clinical signs. Bodyweight was recorded weekly and food consumption was measured daily during the pre-dose period and throughout the treatment period. Achieved dosage was calculated daily. Haematological and blood biochemical investigations were performed from the beginning and at the end of the treatment period. At study end, the animals were killed and submitted to a full macroscopic examination. Designated organs were weighed and tissue specimens were preserved. A microscopic examination was performed on selected tissues from animals in the control and high dose groups. At 500 and 1000 ppm, no overt signs of toxicity were noted. At 2000 ppm, emaciated appearance was recorded in 1/2 males and 1/2 females. Lower bodyweight gain in males and bodyweight loss in females was associated with lower food consumption, probably due to low palatability of the test substance. No treatment-related laboratory or histopathological changes were noted. Under the study conditions, the NOAEL was probably higher than 2000 ppm (i.e. 24 and 23 mg a.i./kg bw/day in males and females, respectively) (CIT, 2007).

Reference 3

Endpoint:

short-term repeated dose toxicity: oral

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

10 Nov, 1988 - 29 Jun, 1989

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Study performed well under GLP and OECD protocol. Page 78 is missing. Questionable reporting of clinical signs. Large spacing between low and mid-doser groups.

Qualifier:

according to guideline

Guideline:

OECD Guideline 407 (Repeated Dose 28-Day Oral Toxicity Study in Rodents)

Deviations:

no

GLP compliance:

yes

Limit test:

no

Species:

rat

Strain:

Crj: CD(SD)

Sex:

male/female

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

The test substance was administered to the rats as solution in distilled water.

Details on analytical verification of doses or concentrations:

Concentrations of the test solutions were analysed at regular intervals as per the study plan.

Duration of treatment / exposure:

28 days

Frequency of treatment:

once a day

Remarks:

Doses / Concentrations:
2.5, 27.5 and 50 mg a.i./kg bw
Basis:
actual ingested

No. of animals per sex per dose:

5 per sex per dose

Control animals:

yes, concurrent vehicle

Details on study design:

Groups of 5 male and 5 female rats were dosed by intragastric intubation daily, 7 days/week for four weeks.

Observations and examinations performed and frequency:

During the treatment period clinical signs, food consumption, body weight  and mortalities were recorded. After the treatment period heamatoloy, blood chemistry, urinalysis and macro-and microscopic examination of tissues was done. Concentrations analysis have been performed on solutions prepared for administration.

Sacrifice and pathology:

After the treatment period of 28 days, necropsy was performed on all surviving animals and macro-and microscopic examinations were performed.

Clinical signs:

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):

effects observed, treatment-related

Food efficiency:

not specified

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

not specified

Ophthalmological findings:

not specified

Haematological findings:

effects observed, treatment-related

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

not specified

Behaviour (functional findings):

not specified

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Histopathological findings: neoplastic:

not examined

Details on results:

Mortalities: One male and two females of high dos group were killed on humane grounds after several days of treatment(days 11 and 15). 
Clinical findings: At 2.5 mg/Kg/day in the females and in all the animals in the higher dosage groups: pilo-erection, increased salivation and hunched posture were observed during the study period. In addition at 27.5 and 50 mg/kg/day, diarrhoea, lethargy, gasping, waddling were noted in all the animals. Abdominal distension, dyspnoea, epitaxis and brown-red staining around the mouth and anal region were also recorded in the high dosage group animals.
Bodyweight: Bodyweight losses and low bodyweight gains were recorded in the 100 mg/kg/day group.
Food consumption:  Food consumption was lower in the high dosage group.
Haematology: Significantly higher (PMacroscopic findings: Crater-like depressions or raised areas were noted in the forestomachs of one male and two females in the high dosage group killed at termination and those killed for humane grounds.
Microscopic pathology: Ulceration/erosion, epithelial hyperplasia and hyperkeratosis of the non-glandular epithelium associated with subepithelial oedema and inflammation were observed amongst rats of the high dosage group either killed at termination or during the study. These changes were not noted in the rats of the other groups.
Other findings: No change biochemical parameters or in organ weights were noted that were considered to related to treatment.

Key result

Dose descriptor:

NOAEL

Effect level:

ca. 2.5 mg/kg bw/day (nominal)

Based on:

act. ingr.

Sex:

male/female

Key result

Dose descriptor:

LOAEL

Effect level:

ca. 27.5 mg/kg bw/day (nominal)

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

other: Effects limited to clinical signs; limited reporting

Key result

Critical effects observed:

not specified

Conclusions:

Under the study conditions, the LOAEL was determined to be 55 mg/kg bw/day and the NOAEL was 2.5 mg/kg bw/day.

Executive summary:

A repeated dose 28 day oral toxicity study in rats was conducted according to laboratory internal methodology (Huntingdon Life Sciences). The following dose levels of DDAC were administered by gavage: 2.5, 28 and 50 mg/kg bw/day. Diarrhoea, lethargy, gasping and waddling were noted in all the animals at the mid dose. Abdominal distension, dyspnoea, epitaxis and brown-red staining around the mouth and anal region were also recorded at the high dose. The following effects were also related to high dose treatment: ulceration/erosion, epithelial hyperplasia and hyperkeratosis of the non-glandular epithelium associated with subepithelial oedema and inflammation. Under the study conditions, the LOAEL was determined to be 55 mg/kg bw/day and the NOAEL was 2.5 mg/kg bw/day (HRC, 1989).

Reference 4

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 409 (Repeated Dose 90-Day Oral Toxicity Study in Non-Rodents)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.27 (Sub-Chronic Oral Toxicity Test: Repeated Dose 90-Day Oral Toxicity Study in Non-Rodents)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.3150 (90-Day Oral Toxicity in Non-rodents)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Species:

dog

Strain:

Beagle

Sex:

male/female

Details on test animals or test system and environmental conditions:

-Species: beagle dogs
-Strain: n.a.
-Source: Marshall Farms, North Rose, New York, USA
-Sex: Male + female
-Age/weight at study initiation: approx. 7 months old (not older than 9 months) at day 1 of treatment mean body weight male: 8.7 kg (range 7.5 kg to 9.7 kg) mean body weight female: 7.5 kg (range: 6.8 kg to 8.1 kg)
-Number of animals per group: 4 males, 4 females / dose group in total 32 animals
-Control animals: Yes

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

Administration/ Exposure: Oral, via diet
Duration of treatment: 14 day pretreatment period and 93 days final test
Frequency of exposure: Continous
Postexposure period: No
Type: application in diet
Concentration 0, 300, 600 and 1200 ppm of the test substance (corresponding to 121.5, 243 or 486 ppm of DDAC) in diet. Food consumption
per day ad libitum. Levels are based on a 4-week preliminary study.
The mean achieved dosages of DDAC, based on food consumption and body weight information were as follows:
males: 0, 4, 8 and 15 mg/kg/day, females: 0, 4, 9 and 18 mg/kg/day
Vehicle: None
Controls: Plain diet

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The levels of achieved doses were measured regularly throughout the study.

Duration of treatment / exposure:

13 weeks

Frequency of treatment:

Daily

Remarks:

Doses / Concentrations:
0, 300, 600 and 1200 ppm of test substance, with 40% a.i. (i.e., 121.5, 243 and 486 ppm a.i.)
Basis:
nominal in diet

Remarks:

Doses / Concentrations:
0, 4, 8 and 15 mg a.i./kg bw/day in males and 0, 4, 9 and 18 mg a.i./kg bw/day of DDAC
Basis:
actual ingested

No. of animals per sex per dose:

4 males, 4 females / dose group in total 32 animals

Control animals:

yes, concurrent vehicle

Details on study design:

Post-exposure period: none

Positive control:

Not applicable

Observations and examinations performed and frequency:

-Clinical signs: Yes, each dog was observed at least once a day, at approximately the same time, for the recording of clinical signs.
Detailed clinical observations were made on all animals, once before the beginning of the treatment period and once a week until the end of the study.
-Mortality: Each animal was checked at least twice a day, including weekends and public holidays, for mortality or signs of morbidity during treatment-Body weight: Yes, before allocation of the animals to groups, on the first day of treatment and then once a week until end of the study.
-Food consumption: Yes, daily per animal
-Water consumption: No recording, water was made available ad libitum.
-Ophthalmoscopic examination: Yes, before the beginning of the treatment period and at the end of the study.
-Haematology: Yes, for all animals, time points: once before the beginning of the treatment period, in week 6 and at the end of the treatment period.
Parameters: Erythrocyte count, Hemoglobin, Mean cell volume, Packed cell volume, Mean cell hemoglobin concentration, Mean cell hemoglobin,
Thrombocyte count, Leucocyte count, Differential white cell count with cell morphology, Reticulocytes count, Prothrombin time, Activated partial
thromboplastin time and Fibrinogen
-Clinical Chemisty: Yes, for all animals, time points: once before the beginning of the treatment period, in week 6 and at the end of the treatment
period. Parameters: Sodium, Potassium, Chloride, Calcium, Inorganic phosphorus, Glucose, Urea, Creatinine, Total biliburin, Total proteins, Albumin,
Albumin/globulin ration, total cholesterol, Triglycerides, Alkaline phosphatase, Aspartate aminotransferase, Alanine aminotransferase, Lactate
deshydrogenase, Creatine kinase, Gamma-glutamyl transferase.
-Urinalysis: Yes, for all animals, time points: once before the beginning of the treatment period, in week 6 and at the end of the treatment period
Parameters: Appearance, Color, Volume, pH, Specific gravity, Proteins, Glucose, Ketones, Bilirubin, Nitrites, Blood, Urobilinogen and Cytology of
sediment.

Sacrifice and pathology:

-Organ Weights: Yes: all animals, organs: adrenals, brain, epididymides, heart, kidneys, liver, ovaries spleen, testes, thymus, thyroids with
parathyroids, uterus (horns and cervix).
-Gross and histopathology: A complete macroscopic post-mortem examination was performed on all study animals. This includes examination of
the external surfaces, all orifices, the cranial cavity, the external surface of the brain and spinal cord, the thoracic, abdominal and pelvic cavities
with there associated organs and tissues and the neck with its associated organs and tissues, which are pituitary, eyes, thyroid, parathyroid,
thymus, oesophagus, pancreas, kidneys, adrenals, spleen, heart, trachea and lungs, aorta, gonads, uterus, accessory sex organs, female
mammary gland, prostate, urinary bladder, lymph nodes, periferal nerve, bone marrow.

Other examinations:

-Other examinations: No

Statistics:

Depending on normal distribution (Kolmogorov–Lilliefors test, possibly after a Logarithmic transformation of the values – except for organ weights) and following testing of homogeneity of variances between groups: Bartlett test (3 or more groups) or Fisher test (2 groups): If Homogeneous
Student test (2 groups) Dunnett test (3 or more groups), else Dunn test (3 or more groups) Mann–Whitney/Wilcoxon test (2 groups) If not normal
distribution: Dunn test.

Clinical signs:

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):

effects observed, treatment-related

Food efficiency:

not specified

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

not examined

Ophthalmological findings:

effects observed, treatment-related

Haematological findings:

effects observed, treatment-related

Clinical biochemistry findings:

effects observed, treatment-related

Urinalysis findings:

effects observed, treatment-related

Behaviour (functional findings):

not specified

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Gross pathological findings:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Histopathological findings: neoplastic:

not examined

Details on results:

No signs indicative of toxicity were observed in any dose group. The mean achieved dosages of DDAC, remained stable during the study in all groups and increased in a dose-proportional manner. Based on food consumption and body weight information, the dose levels for 0, 300, 600 and 1200  ppm of the test substance were as follows:
males: 0, 4, 8 and 15 mg a.i./kg/day females: 0, 4, 9 and 18 mg a.i./kg/day
No unscheduled deaths occurred during the study. No treatment-related clinical signs were observed. There was no direct effect of treatment with the test item on the body weight. No treatment-related ophthalmological findings, no treatment-related relevant differences in hematology and blood biochemistry, no urinary findings among qualitative or quantitative parameters, no effects of toxicological importance on organ weights, no treatment-related necropsy or microscopic findings were observed at any of the dose groups.
NO(A)EL = 1200 ppm (male) corresponding to 15 mg a.i./kg/day DDAC;  = 1200 ppm (female) corresponding to 18 mg a.i./kg/day DDAC

Key result

Dose descriptor:

NOAEL

Effect level:

ca. 15 mg/kg bw/day (nominal)

Sex:

male

Key result

Dose descriptor:

NOAEL

Effect level:

ca. 18 mg/kg bw/day (nominal)

Sex:

female

Key result

Dose descriptor:

NOAEL

Effect level:

ca. 16.5 mg/kg bw/day (nominal)

Sex:

male/female

Basis for effect level:

other: Highest dose

Key result

Critical effects observed:

not specified

None

Conclusions:

The NOAEL was established at 1200 ppm of the test substance corresponding to 15 mg a.i./kg bw/day in males and 18 mg a.i./kg bw/day in females (i.e. 16.5 mg/kg bw combined males/females).

Executive summary:

The repeated dose toxicity of the test substance (40% a.i.) in dogs was evaluated in a study performed according to OECD Guideline 409, EEC Method B.27 and US EPA OPPTS Guideline 870.3150. The substance was administered at 0, 300, 600 and 1200 ppm (corresponding to 121.5, 243 or 486 ppm a.i.) in diet for13 weeksto 4 males and 4 female Beagle dogs per dose group. Food consumption was measured daily. The dose levels were based on a 4-week preliminary study. The mean achieved dosages of DDAC remained stable during the study in all groups and increased in a dose-proportional manner. Based on food consumption and body weight information, the actual ingested dose levels for 0, 300, 600 or 1200 ppm of test substance were as follows: males: 0, 4, 8 and 15 mg a.i./kg bw/day and females: 0, 4, 9 and 18 mg a.i./kg bw/day. No unscheduled deaths occurred during the study. No treatment-related clinical signs were observed. There was no direct effect of treatment on body weight. No treatment-related ophthalmological findings, no treatment-related relevant differences in haematology and blood biochemistry, no urinary findings among qualitative or quantitative parameters, no effects of toxicological importance on organ weights, necropsy findings or microscopic findings were observed in any of the groups. The NOAEL was established at 1200 ppm, corresponding to 15 mg a.i./kg bw/day in males and 18 mg a.i./kg bw/day in females (CIT, 2006). 

Reference 5

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

11 Oct, 2002 - 02 Dec, 2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.26 (Sub-Chronic Oral Toxicity Test: Repeated Dose 90-Day Oral Toxicity Study in Rodents)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

Species: Rat
Strain: Sprague Dawley, Crl CD® (SD) IGS BR
Source: Cesarian Obtained, Barrier Sustained-Virus Antibody Free (COBS-VAF®).
Sex: Male and female
Age/weight at study initiation: 6 weeks at Day 1 of treatment
mean weight males: 185 g, females: 153 g
Number of animals per group: 10 male, 10 female/dose group in total 80 animals
Control animals: Yes

Route of administration:

oral: feed

Vehicle:

other: mixed in diet

Details on oral exposure:

-Duration of treatment: 93 days
-Frequency of exposure: daily
-Postexposure period: No
-Type: Oral via feed
-Concentration food consumption per day: ad libitum 0, 1500, 3000 and 6000 ppm of the test substance
Analysis of food showed dosages were within 10% of nominal concentrations.
-Vehicle: None
-Concentration in vehicle: Not applicable
-Total volume applied: Not applicable
-Controls: Plain diet

Analytical verification of doses or concentrations:

yes

Duration of treatment / exposure:

93 days

Frequency of treatment:

Daily

Remarks:

Doses / Concentrations:
1500, 3000 and 6000 ppm test substance, with 40% a.i. (DDAC)
Basis:
nominal in diet

Remarks:

Doses / Concentrations:
644, 1287 and 2574 ppm a.i.
Basis:
nominal in diet

Remarks:

Doses / Concentrations:
42, 84 and 175 mg a.i./kg bw/day in males and 0, 49, 96 and 201 mg a.i./kg bw/day in females
Basis:
nominal in diet

No. of animals per sex per dose:

10 males and 10 females per dose group

Control animals:

yes, concurrent vehicle

Details on study design:

Post-exposure period: none

Positive control:

Not applicable

Observations and examinations performed and frequency:

Mortality, clinical signs, functional observational battery of tests, body weight, food consumption and ophthalmological examinations were performed during the in-life phase of the study.

Additionally hematological and biochemical analyses were performed at the end of the study.

Sacrifice and pathology:

-Organ Weights Yes: all animals
-organs: adrenals, liver, kidneys, adrenals, testes, epididymides, uterus, ovaries, thymus, thyroid, spleen, brain, heart
-Gross and histopathology: Yes. All animals of control and high dose group, animals that prematurely died, and all macroscopic leasions.
Intermediate are also investigated in full when possible effects are seen in highest dose group.
Macroscopic lesions, Adrenals, Aorta, Brain (including medulla/pons, cerebellar and cerebral corte), Cecum, Colon, Duodenum, Epididymides,
Esophagus, Eyes with Harderian glands, Femoral bone with articulation, Heart, Ileum, Jejunum, Kidneys, Liver, Lungs with bronchi, Lymph nodes
(mandibular and mesenteric), Mammary glands/area, Ovaries (with oviducts), Pancreas, Pituitary gland, Prostate (dorso-lateral and ventral),
Rectum, Salivary glands (sublingual and submandibular), Sciatic nerve, Seminal vesicles (including coagulation gland), Skeletal muscle, Skin,
Spinal cord (cervical, thoracic and lumbar), Spleen, Sternum with bone marrow, Stomach with forestomach, Testes, Thymus, Thyroids with
parathyroids, Tongue, Trachea, Urinary bladder, Uterus (horns and cervi), Vagina.
Additionally, mesenteric lymph nodes of the low and intermediate dose groups, have been examined.

Other examinations:

-Other examinations: Functional observation battery (FOB)

Statistics:

-Statistics: Depending on normal distribution (Kolmogorov–Lilliefors test, possibly after a Logarithmic transformation of the values – except
for organ weights) and following testing of homogeneity of variances between groups: Bartlett test (3 or more groups) or Fisher test (2 groups):
If Homogeneous Student test (2 groups) Dunnett test (3 or more groups), else Dunn test (3 or more groups) Mann–Whitney/Wilcoxon test
(2 groups) If not normal distribution: Dunn test.

Clinical signs:

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):

effects observed, treatment-related

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

not examined

Ophthalmological findings:

effects observed, treatment-related

Haematological findings:

effects observed, treatment-related

Clinical biochemistry findings:

effects observed, treatment-related

Urinalysis findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Gross pathological findings:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Details on results:

CLINICAL EXAMINATIONS:
Mortality - No mortality occurred during the study period. C
linical signs - No relevant clinical signs were observed in any group over the study period.
Body weight & Food consumption - Decreased food consumption and body weight gain were noted in all treated males at 1250, 2500 or 5000 ppm and in females treated at 2500 or 5000 ppm. These effects were considered to be related to palatability of the compound in the diet, resulting in a lower food consumption and lower body weight gain.

PATHOLOGY Organ weights:  Some differences in organ weights were observed between the treated and control animals. However, they were minor and/or not dose-related and were considered to be of no toxicological importance. In addition, the lower absolute and/or higher relative weights observed in most organs in the animals given 5000 ppm were considered to be due , mainly, to the lower final autopsy body weights for the animals of the two sexes from the top doselevel group.

Macroscopic post-mortem examination: The cecum was distended with feces in all the males and 3/6 females given 5000 ppm. The colon was distended with feces in 1/6 males from the same treated group. Considering the nature of the test compound and its dietary admixture, a relationship to treatment cannot be ruled out. The prostate and seminal vesicles were of small size in 3/6 males given 5000 ppm. In one out of these three males, the testes and epididymides were also of small size. In absence of weighing of prostate and seminal vesicles and of microscopic examination, no conclusion can be drawn. The few other macroscopic findings were those which are commonly recorded spontaneously in the untreated laboratory rat of this strain and age and their reported incidence was considered to be of no toxicological importance

Key result

Dose descriptor:

NOAEL

Effect level:

ca. 46 mg/kg bw/day (nominal)

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

other: No toxicologically significant effects in males or females, although some changes in hematological and blood biochemical parameters and a marginal increase in histiocytosis and mastocytosis were observed at this dose level.

Key result

Dose descriptor:

LOAEL

Effect level:

ca. 90 mg/kg bw/day (nominal)

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

other: Treatment related effect on body weight gain, food consumption, changes at clinical pathology and histiocytosis and mastocytosis in mesenteric lymph nodes.

Key result

Critical effects observed:

not specified

Conclusions:

Based on the results, a NOAEL of 1500 ppm of the test substance (corresponding to 45.5 mg a.i./kg bw/day combined males/females) was established. The corresponding LOAEL was 3000 ppm (corresponding to 90 mg/kg bw/day combined males/females).

Executive summary:

In a study compliant with OECD Guideline 408 and EU Method B.26, DDAC (40% a.i.) was given by dietary admixture to Sprague-Dawley rats for 13 weeks at concentrations of 1500, 3000 or 6000 ppm test substance (corresponding to 42, 84 or 175 mg a.i./kg bw/day for males and 49, 96 or 201 mg a.i./kg bw/day for females). At 6000 ppm, main treatment-related findings were soft feces, body weight loss (Week 1), lower body weight gain and food consumption, perturbation of haematological and blood biochemical parameters, distension of the cecum/colon with feces in all animals, histiocytosis, mastocytosis and sinusal haemorrhage in the mesenteric lymph node, consistent with a continued action of a mild irritant. At 3000 ppm, body weight gain and food consumption were affected, changes at clinical pathology were noted, the cecum was distended with feces in about third of the animals, and histiocytosis and mastocytosis in the mesenteric lymph node were seen at histopathology. At 1500 ppm, changes in haematological and blood biochemical parameters were recorded and possibly a marginal increase in histiocytosis and mastocytosis in the mesenteric lymph node which all did not immediately seem to be of toxicological significance. A NOAEL of 1500 ppm of the test substance (corresponding to 46 mg a.i./kg bw/day combined male/female) was established. The corresponding LOAEL was 3000 ppm (corresponding to 90 mg a.i./kg bw/day combined male/female) (CIT, 2004).

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

NOAEL

10 mg/kg bw/day

Study duration:

chronic

Species:

dog

Quality of whole database:

Good quality. In line with the data presented in the DDAC assessment report for Product Type 8 conducted under Directive 98/8/EC (evaluating Competent Authority: Italy, June 2015

Organ:

other: Target organs: Only local effects; no true systemic effects

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

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Reason / purpose for cross-reference:

data waiving: supporting information

Reason / purpose for cross-reference:

data waiving: supporting information

Reason / purpose for cross-reference:

data waiving: supporting information

Critical effects observed:

not specified

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

12 mg/kg bw/day

Quality of whole database:

Data published in the DDAC assessment report for Product Type 8 conducted under Directive 98/8/EC (evaluating Competent Authority: Italy, June 2015

Repeated dose toxicity: dermal - local effects

Link to relevant study records

Reference

Endpoint:

sub-chronic toxicity: dermal

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Reason / purpose for cross-reference:

data waiving: supporting information

Reason / purpose for cross-reference:

data waiving: supporting information

Reason / purpose for cross-reference:

data waiving: supporting information

Critical effects observed:

not specified

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Oral, rats

A repeated dose 28 day oral toxicity study in rats was conducted according to laboratory internal methodology (Huntingdon Life Sciences). The following dose levels of DDAC were administered by gavage: 2.5, 28 and 50 mg/kg bw/day. Diarrhoea, lethargy, gasping and waddling were noted in all the animals at the mid dose. Abdominal distension, dyspnoea, epitaxis and brown-red staining around the mouth and anal region were also recorded at the high dose. The following effects were also related to high dose treatment: ulceration/erosion, epithelial hyperplasia and hyperkeratosis of the non-glandular epithelium associated with subepithelial oedema and inflammation. Under the study conditions, the LOAEL was determined to be 55 mg/kg bw/day and the NOAEL was 2.5 mg/kg bw/day (HRC, 1989).

In a study compliant with OECD Guideline 408 and EU Method B.26, DDAC (40% a.i.) was given by dietary admixture to Sprague-Dawley rats for 13 weeks at concentrations of 1500, 3000 or 6000 ppm test substance (corresponding to 42, 84 or 175 mg a.i./kg bw/day for males and 49, 96 or 201 mg a.i./kg bw/day for females). At 6000 ppm, main treatment-related findings were soft feces, body weight loss (Week 1), lower body weight gain and food consumption, perturbation of haematological and blood biochemical parameters, distension of the cecum/colon with feces in all animals, histiocytosis, mastocytosis and sinusal haemorrhage in the mesenteric lymph node, consistent with a continued action of a mild irritant. At 3000 ppm, body weight gain and food consumption were affected, changes at clinical pathology were noted, the cecum was distended with feces in about third of the animals, and histiocytosis and mastocytosis in the mesenteric lymph node were seen at histopathology. At 1500 ppm, changes in haematological and blood biochemical parameters were recorded and possibly a marginal increase in histiocytosis and mastocytosis in the mesenteric lymph node which all did not immediately seem to be of toxicological significance. A NOAEL of 1500 ppm of the test substance (corresponding to 46 mg a.i./kg bw/day combined male/female) was established. The corresponding LOAEL was 3000 ppm (corresponding to 90 mg a.i./kg bw/day combined male/female) (CIT, 2004).

A study was conducted in accordance with OECD Guideline 453 and OPPTS Guideline 870.3700 to evaluate the chronic toxicity of the test substance (40% a.i.). The test substance was administered daily to Sprague-Dawley rats by dietary admixture at the concentrations of 700, 1500, and 3000 ppm of for 52 weeks (toxicology sub-group) or for 104 weeks. The test substance did not induce any treatment-related mortality or clinical signs when administered daily for 52 or 104 weeks. At 3000 ppm, the mean body weight and mean body weight gain of the carcinogenicity subgroup animals were slightly lower than in controls (-26%), correlating in females with slightly lower mean food consumption during the first 13 weeks. There were no significant differences in hematological, biochemical and/or urinalysis parameters at any treated dose-level for animals of either sub-group, compared with controls. There were no macroscopic findings attributable to the test item at any of the tested dose-levels. The non-neoplastic histopathological findings confined to the mesenteric lymph nodes and Peyer’s patches were consistent with the continued action of a mild irritant and are considered to be of limited toxicological significance. There were no treatment-related neoplastic findings at histologic al examination. Consequently, the LOAEL for toxicity was considered to be 3000 ppm (equivalent to 62 mg/kg bw/day combined male/female) and the NOAEL 1500 ppm (equivalent to 31 mg a.i./kg bw/day, combined male/female). The test substance was not found to be carcinogenic under the conditions of this study (CIT, 2008).  

Oral, dogs  

A study was conducted to determine the toxicity of the test substance (40% a.i.) administered by dietary admixture to Beagle dogs for 4 weeks at concentrations of 500, 1000 and 2000 ppm (i.e. 202.5, 405 and 810 ppm a.i.) in accordance with OECD Guideline 409. The animals were checked daily for mortality and clinical signs. Bodyweight was recorded weekly and food consumption was measured daily during the pre-dose period and throughout the treatment period. Achieved dosage was calculated daily. Haematological and blood biochemical investigations were performed from the beginning and at the end of the treatment period. At study end, the animals were killed and submitted to a full macroscopic examination. Designated organs were weighed and tissue specimens were preserved. A microscopic examination was performed on selected tissues from animals in the control and high dose groups. At 500 and 1000 ppm, no overt signs of toxicity were noted. At 2000 ppm, emaciated appearance was recorded in 1/2 males and 1/2 females. Lower bodyweight gain in males and bodyweight loss in females was associated with lower food consumption, probably due to low palatability of the test substance. No treatment-related laboratory or histopathological changes were noted. Under the study conditions, the NOAEL was probably higher than 2000 ppm (i.e. 24 and 23 mg a.i./kg bw/day in males and females, respectively) (CIT, 2007).

 

The repeated dose toxicity of the test substance (40% a.i.) in dogs was evaluated in a study performed according to OECD Guideline 409, EEC Method B.27 and US EPA OPPTS Guideline 870.3150. The substance was administered at 0, 300, 600 and 1200 ppm (corresponding to 121.5, 243 or 486 ppm a.i.) in diet for 13 weeks to 4 males and 4 female Beagle dogs per dose group. Food consumption was measured daily. The dose levels were based on a 4-week preliminary study. The mean achieved dosages of DDAC remained stable during the study in all groups and increased in a dose-proportional manner. Based on food consumption and body weight information, the actual ingested dose levels for 0, 300, 600 or 1200 ppm of test substance were as follows: males: 0, 4, 8 and 15 mg a.i./kg bw/day and females: 0, 4, 9 and 18 mg a.i./kg bw/day. No unscheduled deaths occurred during the study. No treatment-related clinical signs were observed. There was no direct effect of treatment on body weight. No treatment-related ophthalmological findings, no treatment-related relevant differences in haematology and blood biochemistry, no urinary findings among qualitative or quantitative parameters, no effects of toxicological importance on organ weights, necropsy findings or microscopic findings were observed in any of the groups. The NOAEL was established at 1200 ppm, corresponding to 15 mg a.i./kg bw/day in males and 18 mg a.i./kg bw/day in females(CIT, 2006). 

Further, the DDAC assessment report for Product Type 8 conducted under Directive 98/8/EC (evaluating Competent Authority: Italy, June 2015, attached in Section 13 of the IUCLID dataset) reported additional repeated dose toxicity studies with DDAC, which are summarised below: 

The subchronic oral NOAELs were 107-134 mg/kg bw/day in male and female mice and 61-74 mg/kg bw/day in male and female rats mainly based on aspecific effects, such as decreased body weights, considered to be secondary to local effects on gut mucosa and intestinal microflora. No organ specific toxicity was evidenced. With both rodent species high mortality (80% and 96% of treated rats and mice) occurred in animals given DDAC fortified diets at the highest dose tested; death was attributed to gastrointestinal alterations resulting in dehydration and wasting. The exposure to the immediately lower dose caused only minimal body weight effects (10-15% decrease). The steepness of the dose-response curve (from no effects to high % mortality caused by 3-fold higher dose) is also indicative of the mechanism of action through irritation/corrosive properties of DDAC (US ISC; cited in the ECHA biocides assessment report, 2015).  

In a 1-year oral gavage study in dogs with DDAC, the two highest doses (10 and 20 mg/kg bw/day) resulted in G.I. related complications including emesis and abnormal faeces. The clinical signs observed in all the animals treated at 10 mg/kg bw/day (emesis, salivation, soft/loose faeces) persisted for the entire study duration; taking into account that the treatment dosage is reached with 2 different administrations within the day (lowering the entity of the bolus dose achievable with a single administration-possibly giving rise to more severe effects) this dosage cannot be considered as the NOAEL derived from the study. The NO(A)EL should be fixed equal to 3 mg/kg bw/day, related to local effects on gut mucosa. The clinical signs reported at 10 mg/kg bw/day, on which the NOAEL derivation is based, are consistent with the irritation/corrosive properties of the test item: only a small amount of DDAC becomes systemically available, without giving rise to any significant systemic effects. The systemic effects (10-15% decrease in body weight), were seen at 20/30 mg/kg bw/day, although secondary to effects in the gut. In this context, the AEL cannot be regarded as a “true” systemic threshold and therefore, at WGII2015 it has been agreed that the AEL approach should not be performed. Consequently, only a qualitative local risk assessment (including exposure assessment) have to be considered from the use of DDAC (US ISC; cited in the ECHA biocides assessment report, 2015).  

The NOAELs for non-neoplastic effects after chronic dietary DDAC administration were 32-41 mg/kg bw/day for rats and 76 – 93 mg/kg bw/day for mice. NOAELs values derivation was mainly based on unspecific effects, such as decreased body weights, considered to be secondary to local effects on gut mucosa and intestinal microflora. No organ specific toxicity was evidenced. In line with the fact that the main outcome directly derives from the irritative/corrosive properties of the active substance, the subchronic and chronic NOAELs are similar in rodents, and little difference is expected between the 2-exposure scenario (US ISC; cited in the ECHA biocides assessment report, 2015).  

The RMS further concluded the NOAEL for local effects and systemic effects at 3 and 10 mg/kg bw/day, based on sub-chronic studies of US ISC in dogs and the non-neoplastic NOAEL at 27 mg/kg bw/day based on the long-term study in rats (EQC).

 

Dermal 

 

Due to the direct corrosive effect and limited dermal absorption, effects will be characterised by local tissue damage rather than systemic toxicity. Available information on dermal absorption makes a route-to-route approach possible. 

Further, the DDAC assessment report for Product Type 8 conducted under Directive 98/8/EC (evaluating Competent Authority: Italy, June 2015, attached in Section 13 of the IUCLID dataset) reported a subchronic repeated dose dermal study with DDAC, where no systemic effects were seen at the highest dose that could be applied without excessive skin irritation. Therefore, the systemic NOAEL was 12 mg/kg bw/day (highest dose tested) and the local NOAEL was 2 mg/kg bw/day (US ISC; cited in the ECHA biocides assessment report, 2015).

Inhalation 

The test substance has low vapour pressure and therefore will be present in air only at negligible concentrations under normal and foreseeable use conditions. Further inhalation testing in animals was therefore not considered necessary. Moreover, since the substance is classified as corrosive, testing would be excessively harmful to the animals. 

 

Overall assessment

When evaluating all available studies, it becomes clear that the effects are characterised by local gastro-intestinal irritation rather than by systemic toxicity. The effects that are seen at the LOAEL consist of decreased bodyweight gain and food consumption, with or without clinical symptoms. There are no signs of haematological, biochemical or histopathological nature that would indicate systemic or organ toxicity. This is the case in dietary as well as in gavage studies. The NOAELs do not change with increasing duration of the study (especially on the basis of concentration in the diet what compensated for allometric scaling and metabolic changes with age). This lack of increased toxicity with duration represents a further indication for a lack of systemic toxicity. 

Justification for classification or non-classification

Based on the results from the repeated dose oral studies, the test substance does not warrant a classification for STOT REaccording to EU CLP (Regulation EC/1272/2008) criteria.