Tributylmethylammonium chloride

Endpoint summary

Description of key information

Two acute oral and two acute dermal toxicity studies are available, all performed with MTBAC according to OECD/EC test guidelines and GLP principles. The acute oral LD50 is >2000 mg/kg/bw based on a weight of evindence and the acute dermal LD50 is >1000 <2000 mg/kg bw.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Reference 1

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

April 13, 2015 - May 26, 2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

This endpoint study record is part of a Weight of Evidence approach comprising two acute oral toxicity studies. Both data sources are sufficient to fulfil the information requirements as further explained in the provided endpoint summary.

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Deviations:

no

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

no

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: AMTBC14001
- Expiration date of the lot/batch: August 22, 2016

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room temperature
- Stability under test conditions: The stability of the test item under storage conditions over the study period was guaranteed by the sponsor, and the sponsor holds this responsibility.

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Wiga GmbH, Germany
- Age at study initiation: ca. 10 weeks
- Weight at study initiation: Animals of comparable weight (± 20% of the mean weight)
- Fasting period before study: Feed was withdrawn from the animals at least 16 hours before administration, but water was available ad libitum.
- Housing: Single housing
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22°C +- 3°C
- Humidity (%): 30 – 70%
- Air changes (per hr): ca. 10
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 3 and 20 g/100 mL
- Amount of vehicle: 10 mL/kg

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg

Doses:

300 and 2000 mg/kg

No. of animals per sex per dose:

6 (300 mg/kg) or 3 (2000 mg/kg) female rats

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: A check for any dead or moribund animals was made at least once each workday; these records are archived by Bioassay. Clinical signs for each animal were recorded several times on the day of administration and at least once during each workday thereafter. Individual body weights shortly before administration (day 0), weekly thereafter and on the last day of observation.
- Necropsy of survivors performed: yes/no
- Other examinations performed: clinical signs, body weight, Necropsy with gross-pathology examination was performed on the last day of the observation period after sacrifice by CO2-inhalation in a chamber with gradually increasing concentrations. Necropsy of all animals that died as early as possible after death.

Statistics:

N/A

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 300 - < 2 000 mg/kg bw

Based on:

test mat.

Mortality:

In the single 2000 mg/kg test group two animals died within 1 or 2 hours after administration, respectively.
No mortality occurred in in both 300 mg/kg test groups.

Clinical signs:

other: In the single 2000 mg/kg bw test group one animal showed impaired general state and piloerection at hour 1 after administration and was found dead at hour 2. A second animal showed poor general state, piloerection, dyspnea, abdominal position and clonic c

Gross pathology:

The following macroscopic pathologic findings were observed in the two animals that died in the 2000 mg/kg bw test group:
- Dark red discoloration of the liver
- Bleedings into the glandular stomach
- Red discoloration of the small intestine
There were no macroscopic pathological findings in all animals sacrificed at the end of the observation period (one animal of the 2000 mg/kg bw test group; six animals of both 300 mg/kg bw test groups).

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

In an acute oral toxicity study with female rats, performed according to OECD test guidelines and GLP principles, an LD50 >300 <2000 mg/kg bw was determined for MTBAC.

Executive summary:

In an acute oral toxicity study performed with the substance according to OECD TG 423, doses of 2000 and 300 mg/kg bw were administered by gavage to three test groups of three fasted Wistar rats each (2000 mg/kg bw in 3 females and 300 mg/kg bw in 6 females). Mortality was observed in two animals of the 2000 mg/kg bw test group. As substance-related clinical signs poor general state, dyspnea, piloerection, ataxia, cowering position, abdominal position and clonic convulsions were observed at this dose level. Macroscopic pathological findings in the two animals that died were dark red discoloration of the liver, bleedings into the glandular stomach and red discoloration of the small intestine. No mortality occurred at the 300 mg/kg bw dose level. As test-item related clinical signs impaired general state, piloerection and reduced defecation were reported. There were no macroscopic pathological findings in the surviving animals sacrificed at the end of the observation period. The mean body weight of the surviving animals increased within the normal range throughout the study period with two exceptions in the second 300 mg/kg test group. The mean body weights of these animals increased in a normal range during the first week but did not adequately increase during the second week. This effect is observed at times in the rat strain used, because in the required age range the female animals have already reached the phase of slow growth. Based on these results the acute oral LD₅₀was calculated to be LD₅₀, oral, rat > 300 < 2000 mg/kg bw.

Reference 2

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

12MAY2015 - 04JUN2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

This endpoint study record is part of a Weight of Evidence approach comprising two acute oral toxicity studies. Both data sources are sufficient to fulfil the information requirements as further explained in the provided endpoint summary.

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Version / remarks:

(2001)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

Version / remarks:

(May 2008, including the most recent amendments)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

Version / remarks:

(2002)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: Japanese Ministry of Agriculture, Forestry and Fisheries (JMAFF), 12 Nousan, Notification No 8147, November 2000, including the most recent partial revisions.

Deviations:

no

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

no

Specific details on test material used for the study:

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: The preparations (w/w) were kept at room temperature and were dosed within 4 hours after adding the vehicle to the test substance. Homogeneity was obtained to visually acceptable levels and the formulations were stirred during dosing, which ensures homogeneity sufficient for these kinds of studies. No correction was made for purity of the test substance.

Species:

rat

Strain:

other: Crl:WI (Han)

Sex:

female

Details on test animals or test system and environmental conditions:

- Source: Charles River Deutschland, Sulzfeld, Germany.
- Age at study initiation: Young adult animals (approx. 9 weeks old)
- Weight at study initiation: 168-175g
- Fasting period before study: yes (o/n prior to dosing and 3-4 hours after administration of the test substance)
- Housing: Group housing of 3 animals per cage in labeled Macrolon cages
- Diet: Free access to pelleted rodent diet (SM R/M-Z from SSNIFF® Spezialdiäten GmbH, Soest, Germany).
- Water: Free access to tap water.
- Acclimation period: At least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18 – 24
- Humidity (%): 40 - 70
- Air changes (per hr): at least 10
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 12MAY2015 - 04JUN2015

Route of administration:

oral: gavage

Details on oral exposure:

GAVAGE METHOD: plastic feeding tubes.

Frequency: single dosage, on day 1.

VEHICLE: water

MAXIMUM DOSE VOLUME APPLIED: 2000 mg/kg (10 mL/kg) body weight.

DOSAGE PREPARATION: The preparations (w/w) were kept at room temperature and were dosed within 4 hours after adding the vehicle to the test substance. Homogeneity was obtained to visually acceptable levels and the formulations were stirred during dosing, which ensures homogeneity sufficient for these kinds of studies. No correction was made for purity of the test substance.

Doses:

2000 mg/kg body weight (10 mL/kg bw)

No. of animals per sex per dose:

6 (2 groups of three females in a stepwise manner)

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing:
Mortality/Viability: Twice daily
Body weights: Days 1 (pre-administration), 8 and 15
Clinical signs: At periodic intervals on the day of dosing (day 1) and once daily thereafter, until day 15.
- Necropsy of survivors performed: The animals surviving to the end of the observation period were sacrificed by oxygen/carbon dioxide procedure. All animals assigned to the study were subjected to necropsy and descriptions of all internal macroscopic abnormalities recorded.

Statistics:

No statistical analysis was performed (The method used is not intended to allow the calculation of a precise LD50 value).

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

One animal was found dead on day 1. No further mortality occurred.

Clinical signs:

other: Hunched posture and/or piloerection were noted for all animals on day 1. No other substance related effects were noted.

Gross pathology:

Abnormalities of the stomach (distended with gas) were found in the animal that died during the study, at macroscopic post mortem examination. Macroscopic post mortem examination of surviving animals did not reveal any abnormalities.

Interpretation of results:

GHS criteria not met

Conclusions:

In an acute oral toxicity study with female rats, performed according to OECD/EC test guidelines and GLP principles, an LD50 >2000 mg/kg bw was determined for MTBAC.

Executive summary:

An acute oral toxicity study was performed with female rats, according to OECD/EC test guidelines and GLP principles. One animal was found dead on day 1, no further mortality occurred. Hunched posture and/or piloerection were noted for all animals on day 1. No other substance related effects were noted. No effects on body weight gain were found. The stomach of the deceased rat was distended with gas, no other macroscopic observations were done.

Based on these results it is concluded that the LD50 of MTBAC exceeds 2000 mg/kg bw.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

The studies have been performed according to OECD and/or EC guidelines and according to GLP principles (Klimisch 1).

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Reference 1

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1200 (Acute Dermal Toxicity)

GLP compliance:

yes

Test type:

standard acute method

Limit test:

no

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: MJV59-115-1

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Kuiper Rabbitry, Gary, Indiana
- Age at study initiation: at least 12 weeks
- Weight at study initiation: between 2.01 - 2.55 kg
- Housing: individually in stainless steel cages
- Diet: Purina Rabbit Chow, ad libitum
- Water: Tap water, ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 16-22
- Humidity (%): 30-70

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: the dorsal and ventral areas of the trunks of the rabbits were shaved (electric clippers), the areas shaved were approximately 30% of the total body surface area
- % coverage: approx. 10
- Type of wrap if used: Two layers of porous gauze dressing and a sleeve of plastic sheeting was fitted over the shaven trunk of the animal and secured in place with non-irritating surgical tape.

REMOVAL OF TEST SUBSTANCE
- Washing: remaining test article wiped off
- Time after start of exposure: 24 hours

Duration of exposure:

24 hours

Doses:

2000 and 200 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Animals were observed frequently during the day of dosing and once daily for 14 days following dosing. The weight of each animal was determined prior to dosing, and for survivors at 7 days and at the end of the 14 days.
- Necropsy of survivors performed: yes

Statistics:

At the end of the observation period, calculations of the LD50 and 95% confidence limits are performed, if necessary, by the method of moving averages, using the tables constructed by Weil, (Weil C.C.: Table for Convenient Calculations of Median Effective Dose (LD50 and ED50) and lnstruction in Their use). Biometrics, 8, 249 (1952).

Sex:

male/female

Dose descriptor:

LD50

Effect level:

ca. 2 000 mg/kg bw

Based on:

test mat.

95% CL:

>= 1 851.928 - <= 2 159.911

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

ca. 1 500 mg/kg bw

Based on:

act. ingr.

95% CL:

>= 1 388.925 - <= 1 619.933

Remarks on result:

other: Aliquat 175 consists of ca. 75 % tributylmethylammonium chloride (56375-79-2) and ca. 25 % water

Mortality:

At the 2000 mg/kg body weight level, 50% mortality occurred during the 14 day observation period. At the 200 mg/kg body weight level, no mortality occurred during the 14 day observation period.

Clinical signs:

other: At the 2000 mg/kg bw dose level, all animals were extremely hyperactive (excessive jumping and thrashing about in the cage) immediately following dosing. Most likely indicative of discomfort from application of the test material. Additionally, edema at th

Gross pathology:

There were no internal or external changes found in the 200 mg/kg dose group. In the 2000 mg/kg dose group no gross changes were found however, some minor effects were observed. For details see the table in: " Any other information on results incl. tables"

Table 1: Body weight and clinical signs

DOSE group 2000 mg/kg
RABBIT	SEX	Initial BWT	Dose	7 DAY BWT	14 DAY BWT	FATE	FINDINGS
		(kg)	(grams)	(kg)	(kg)
546	M	2.25	4.50	---	---	Day of dosing	External: No gross changes observed. InternaL: Stomach slightly distended with gas, no other gross changes observed.
547	M	2.30	4.60	2.34	2.52	Survived	External: Eschar at the application site, no other gross changes observed.Internal: No gross changes observed.
548	M	2.36	4.72	---	---	Day of dosing	External: No gross changes observed.Internal: No gross changes observed.
549	M	2.32	4.64	2.39	2.65	Survived	External: Eschar at the application site, no other gross changes observed.Internal: No gross changes observed.
550	M	2.51	5.02	---	---	Day of dosing	External: No gross changes observed.Internal: No gross changes observed.
551	F	2.42	4.84	---	---	day 1	External: Erythema and edema present at theapplication site, no other gross changes observed.Internal: Stomach slightly distended with gas, no other gross changes observed.
552	F	2.55	5.10	---	---	Day of dosing	External: No gross changes observed.Internal: Liver appeared mottled, no gross changes observed.
553	F	2.32	4.64	2.20	2.33	Survived	External: Eschar at the application site, no other gross changes observed.Internal: No gross changes observed.
554	F	2.10	4.20	1.96	2.16	Survived	External: Eschar at the application site, no other gross changes observed.Internal: No gross changes observed.
555	F	2.01	4.02	1.82	1.97	Survived	External: Eschar at the application site, no other gross changes observed.Internal: No gross changes observed.

Table 2: Body weight and clinical signs

DOSE group 200 mg/kg
RABBIT	SEX	Initial BWT	Dose	7 DAY BWT	14 DAY BWT	FATE	FINDINGS
		(kg)	(grams)	(kg)	(kg)
594	F	2.10	0.42	2.29	2.53	Survived	External: No gross changes observed.Internal: No gross changes observed.
595	F	2.21	0.44	2.43	2.60	Survived	" "
596	F	2.24	0.45	2.42	2.58	Survived	" "
597	F	2.11	0.42	2.34	2.36	Survived	" "
598	F	2.29	0.46	2.41	2.47	Survived	" "
601	M	2.23	0.45	2.41	2.49	Survived	" "
602	M	2.22	0.44	2.38	2.43	Survived	" "
603	M	2.10	0.42	2.26	2.43	Survived	" "
604	M	2.25	0.45	2.39	2.52	Survived	" "
605	M	2.47	0.49	2.63	2.75	Survived	" "

Probitanalysis according to Finney including the 1000 mg/kg dose level of the second study:

Males

Dose: Number: Number survivors:

200 5 5

1000 5 5

2000 5 2

LD50 95% KI (lower) 95% KI (upper)

--------- -------------- --------------

1952.133 1755.310 2171.025

Intercept Slope

--------- ---------

-79.24 10.458

Goodness-of-Fit - Test (Pearson Chi-Square)

p-value

---------

1.0000

Females

Dose: Number: Number survivors:

200 5 5

1000 5 5

2000 5 3

LD50 95% KI (lower) 95% KI (upper)

--------- -------------- --------------

2052.734 1831.243 2301.015

Intercept Slope

--------- ---------

-74.24 9.735

Goodness-of-Fit - Test (Pearson Chi-Square)

p-value

---------

1.0000

Males and Females

Dose: Number: Number survivors:

200 10 10

1000 10 10

2000 10 5

LD50 95% KI (lower) 95% KI (upper)

--------- -------------- --------------

2000.000 1851.928 2159.911

Intercept Slope

--------- ---------

-76.76 10.099

Goodness-of-Fit - Test (Pearson Chi-Square)

p-value

---------

1.0000

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

Based on an acute dermal toxicity study performed with MTBAC according to OPPTS 870.1200 guideline and GLP principles, it is concluded that the LD50 of MTBAC exceeds 2000 mg/kg bw/day. Corrected for the purity the LD50 for acute dermal exposure is ca. 1500 mg/kg bw.

Executive summary:

In an OPPTS 870.1200 guideline study, rabbits were treated with 200 and 2000 mg/kg bw. The test substance was applied dermally under occlusive conditions for 24 hours. No mortality occurred in the 200 mg/kg bw dose group however, 5 out of 10 animals died in the 2000 mg/kg bw dose group. Erythema, edema and eschar formation were observed during the observation period in the 2000 mg/kg bw dose group. In animals of the 200 mg/kg bw dose group edema and erythema were observed during day 1 to 3. No effects were observed after necropsy. The LD₅₀ for acute dermal exposure is ca. 2000 mg/kg bw in the rabbit. The test item consists of ca. 75 % tributylmethylammonium chloride and ca. 25 % water. Corrected for the purity the LD₅₀ for acute dermal exposure is ca. 1500 mg/kg bw.

Reference 2

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

09 February 2016 - 28 June 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Version / remarks:

(1987)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.3 (Acute Toxicity (Dermal))

Version / remarks:

Official Journal of the European Union No. L142, May 2008, including most recent amendments.

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1200 (Acute Dermal Toxicity)

Version / remarks:

Office of Prevention, Pesticides and Toxic Items (7101), EPA 712-C-98-192, August 1998.

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: Japanese Ministry of Agriculture, Forestry and Fisheries (JMAFF), 12 Nousan, Notification No 8147

Version / remarks:

November 2000; including the most recent partial revisions.

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Specific details on test material used for the study:

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: MTBAC was dissolved in water. The preparations (w/w) were kept at room temperature and dosed within 4 hours after adding the vehicle to the test item. Homogeneity was assessed by visual inspection of the solutions and the formulations were stirred during dosing, which ensures homogeneity sufficient for these kinds of studies. No correction was made for purity of the test item.
- Final dilution: The concentration of the test item in vehicle was varied to allow constant dosage volume in terms of mL/kg body weight.

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland, Sulzfeld, Germany
- Age at study initiation:approx. 9-12 weeks
- Weight at study initiation: 235-293 (males); 181-223g (females)
- Fasting period before study: no
- Housing: Individually housed in labeled Makrolon cages
- Diet: Free access to pelleted rodent diet (SM R/M-Z from SSNIFF® Spezialdiäten GmbH, Soest, Germany)
- Water: Free access to tap water
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS (set values)
- Temperature (°C): 18-24
- Humidity (%): 40-70
- Air changes (per hr): at least 10
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 09 February 2016 To: 28 June 2016

Type of coverage:

occlusive

Vehicle:

water

Details on dermal exposure:

TEST SITE
- Area of exposure: 18 cm²
- % coverage: approx. 10% of the total body surface
- Type of wrap if used: surgical gauze patch, successively covered with aluminum foil fixated with Coban elastic bandage and Micropore tape

REMOVAL OF TEST SUBSTANCE
- Washing: yes, tap water
- Time after start of exposure: dressings of the surviving animals were removed after approximately 4 hours

TEST MATERIAL
- Amount applied: 10 mL/kg body weight (initial 3 females only), 20 mL/kg bw (remaining animals)

PREPARATION:
The preparation (w/w) was dosed within 4 hours after adding the vehicle to the test item. Homogeneity was assessed by visual inspection of the solutions and the formulations were stirred during dosing, which ensures homogeneity sufficient for these kinds of studies. No correction was made for purity of the test item.

Duration of exposure:

Maximum 4 hours

Doses:

200, 1000, 2000 mg/kg bw

No. of animals per sex per dose:

200 mg/kg bw: 1 female;
1000 mg/kg bw: 1 female
2000 mg/kg bw: 8 females, 5 males

Control animals:

not required

Details on study design:

- Duration of observation period following administration: 14 days (scheduled observation time)
- Mortality/Viability was checked regularly during exposure time.
- Body weights were recorded day 1 (pre-administration)
- Necropsy of survivors performed: yes
- Clinical signs were recorded at periodic intervals on the day of dosing (day 1)

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred in the animals treated at 20 mL/ kg bw.

Clinical signs:

other: No clinical signs were noted for the animal treated at 200 mg/kg bw. The animal treated at 1000 mg/kg bw showed restless behavior, piloerection and chromodacryorrhoea (snout) between days 1 and 4. At 2000 mg/kg bw (20 mL/kg), restless behavior, hunched po

Gross pathology:

No full thickness destruction of the skin was noted, indicating that no corrosion of the skin had occurred and no further abnormalities were found at macroscopic post mortem examination of the animals.

Other findings:

Thickened area, erythema, scales and/or scabs, were noted for the treated skin-area of all animals treated at 2000 mg/kg bw(20 mL/kg) during the observation period. In four males and one female these local effects were more severe. These animals showed signs of necrosis from day 2 of the study onwards (one male only on day 2) which resulted in fissures, wounds or scar tissue on day 15. These local effects were considered not to have affected the conclusion of the study.

Results of three females treated at 10mL/ kg bw, at 2000 mg/kg bw:

Approximately 1.5 hours after dosing, the bandage of one animal was removed due to restless behaviour of the animals. When no abnormalities were found the same patch was applied again. Clinical signs consisted of restless behaviour (all animals directly after treatment), flat posture and prosis in 2/3 rats (after 1,5 hours of exposure) and flat- and hunched posture, uncoordinated movements, quick breathing, shallow respiration, piloerection and/or ptosis (after 4 hours exposure). Approximately 4 hours after dosing, one animal was found dead. Severe skin reactions (signs of necrosis) were noted for this animal. For animal welfare reasons, the dressings of the remaining two animals were removed at approximately 4 hours after dosing. Severe skin reactions (signs of necrosis) were noted for the deceased animal. Macroscpic examination showed no full thickness destruction of the skin, indicating that no corrosion of the skin had occurred. The surviving animals showed severe general erythema, thickened areas and blue discolouration in the treated skin-area of the animals after removal of the bandage. On day 2, the skin reactions were resolving. A lower grade of general erythema was noted and scabs were noted for the animals. On day 3 the treated skin showed erythema maculate and scabs. Additionally, one of the animals showed scales and thickened areas of the treated skin. No further abnormalities were found at macroscopic post mortem examination in any of the treated animals. No abnormalities were found at macroscopic post mortem examination of the animals.No full thickness destruction of the skin was noted, indicating that no corrosion of the skin had occurred and no further abnormalities were found at macroscopic post mortem examination of the animals. When it was ruled out that the treated skin or signs of systemic toxicity of the two remaining animals worsened the animals were sacrificed on day 3. It was concluded that local effects rather than systemic effects caused death, therefore a lower dilution was choosen to assess dermal toxicity in order to avoid dermal reactions of the treated rats.

Interpretation of results:

GHS criteria not met

Conclusions:

Based on an acute dermal toxicity study performed with MTBAC according to OECD/EC guidelines and GLP principles, it is concluded that the LD50 of MTBAC exceeds 2000 mg/kg bw/day.

Executive summary:

An acute dermal toxicity study was performed with MTBAC according to OECD/EC guidelines and GLP principles. Three females were dosed at 2000 mg/kg bw, at 20 mL/kg bw. Severe local effects resulted in death of one rat and the other two were sacrificed before end of the study. In a step—wise approach, three individual females were treated at 200, 1000 and 2000 mg/kg bw/ day (at 20 mL/kg bw). Subsequently, three females were treated at 2000 mg/kg bw (20 mL/kg bw) followed by a group of five males and one female. No mortality occurred in these rats. No clinical signs were noted for the animal treated at 200 mg/kg bw, at 1000 mg/kg bw restless behavior, piloerection and chromodacryorrhoea (snout) between days 1 and 4 was seen and at high dose restless behavior, hunched posture, quick breathing, shallow respiration and/or chromodacryorrhoea were noted between days 1 and 3. Only at 2000 mg/kg bw/day (20 mL/kg bw), local effects were seen, which included thickened area, erythema, scales and/or scabs. In four males and one female signs of necrosis from day 2 of the study onwards (one male only on day 2) were seen, which resulted in fissures, wounds or scar tissue on day 15. However, no full thickness destruction of the skin was noted, indicating that no corrosion of the skin had occurred and no further abnormalities were found at macroscopic post mortem examination of the animals. In none of these rats unexpected effects on body weight (gain) were observed. Taken all data together it is concluded that the LD50 of MTBAC exceeds 2000 mg/kg bw/day.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

1 000 mg/kg bw

Quality of whole database:

The studies have been performed according to OECD, EC and/or OPPTS guidelines and according to GLP principles (Klimisch 1).

Additional information

Two acute oral toxicity studies are available.

In an acute oral toxicity study performed with MTBAC according to OECD TG 423 and in accordance with GLP principles, doses of 2000 and 300 mg/kg bw were administered by gavage to three test groups of three fasted Wistar rats each (2000 mg/kg bw in 3 females and 300 mg/kg bw in 6 females). Mortality was observed in two animals of the 2000 mg/kg bw test group. Substance-related clinical signs at this dose level included poor general state, dyspnea, piloerection, ataxia, cowering position, abdominal position and clonic convulsions. Macroscopic pathological findings in the two animals that died were dark red discoloration of the liver, bleedings into the glandular stomach and red discoloration of the small intestine. No mortality occurred at the 300 mg/kg bw dose level. As test-item related clinical signs impaired general state, piloerection and reduced defecation were reported. There were no macroscopic pathological findings in the surviving animals sacrificed at the end of the observation period. The mean body weight of the surviving animals increased within the normal range throughout the study period with two exceptions in the second 300 mg/kg test group. The mean body weights of these animals increased in a normal range during the first week but did not adequately increase during the second week. This effect is observed at times in the rat strain used, because in the required age range the female animals have already reached the phase of slow growth.

An acute oral toxicity study with methyltributylammoniumchloride (MTBAC) was performed with female rats, according to OECD/EC test guidelines and GLP principles. One animal was found dead on day 1, no further mortality occurred. Hunched posture and/or piloerection were noted for all animals on day 1. No other substance related effects were noted. No effects on body weight gain were found. The stomach of the deceased rat was distended with gas, no other macroscopic observations were done.

In both studies, female Wistar rats were dosed and in a weight of evidence approach, overall 3/9 rats died at a dose level of 2000 mg/kg bw. Thus, the oral LD₅₀ of MTBAC is >2000 mg/kg bw .

 

Two key acute dermal toxicity studies, one in rabbits and one in rats, and one supporting acute dermal toxicity study in rabbits are available.

An acute dermal toxicity study in rabbits was performed with the test item according to OPPTS 870.1200 guideline and in accordance with GLP principles. Five Rabbits per sex were treated with 200 and 2000 mg/kg bw. The test substance was applied dermally under occlusive conditions for 24 hours. No mortality occurred in the 200 mg/kg bw dose group however, 5 out of 10 animals died in the 2000 mg/kg bw dose group. Erythema, edema and eschar formation were observed during the observation period in the 2000 mg/kg bw dose group. In animals of the 200 mg/kg bw dose group edema and erythema were observed during day 1 to 3. No effects were observed after necropsy. The LD₅₀ for acute dermal exposure is ca. 2000 mg/kg bw in the rabbit. The test item consists of ca. 75 % MTBAC and ca. 25 % water. Corrected for the purity the LD₅₀ for acute dermal exposure is ca. 1500 mg/kg bw.

As supporting information an acute dermal toxicity study in rabbits is available performed according to OPPTS 870.1200 guideline and in accordance with GLP principles. Rabbits were treated with 1000 mg/kg bw of the test item which was applied dermally under occlusive conditions for 24 hours. No mortality occurred. Erythema, edema and eschar formation were observed during the observation period. No effects were observed after necropsy. The test item consists of ca. 75 % MTBAC and ca. 25 % water. Corrected for the purity, the dermal LD₅₀of MTBAC was determined to be >750 mg/kg bw.

An acute dermal toxicity study in rats was performed with MTBAC according to OECD/EC guidelines and GLP principles. Three females were dosed at 2000 mg/kg bw, at 20 mL/kg bw. Severe local effects resulted in death of one rat and the other two were sacrificed before end of the study. In a step—wise approach, three individual females were treated at 200, 1000 and 2000 mg/kg bw/ day (at 20 mL/kg bw). Subsequently, three females were treated at 2000 mg/kg bw (20 mL/kg) followed by a group of five males and one female. No mortality occurred in these rats. No clinical signs were noted for the animal treated at 200 mg/kg bw, at 1000 mg/kg bw restless behavior, piloerection and chromodacryorrhoea (snout) between days 1 and 4 was seen and at high dose restless behavior, hunched posture, quick breathing, shallow respiration and/or chromodacryorrhoea were noted between days 1 and 3. Only at 2000 mg/kg bw/day (20 mL/kg bw), local effects were seen, which included thickened area, erythema, scales and/or scabs. In four males and one female signs of necrosis from day 2 of the study onwards (one male only on day 2) were seen, which resulted in fissures, wounds or scar tissue on day 15. However, no full thickness destruction of the skin was noted, indicating that no corrosion of the skin had occurred and no further abnormalities were found at macroscopic post mortem examination of the animals. In none of these rats unexpected effects on body weight (gain) were observed. Based on the results of the study it is concluded that the LD₅₀ of MTBAC exceeds 2000 mg/kg bw/day.

Based on all results available, it is concluded that the dermal LD₅₀ of MTBAC is >1000 <2000 mg/kg bw.

 

Justification for classification or non-classification

Based on the available data, methyltributylammoniumchloride (MTBAC) is classified for acute dermal toxicity Cat. 4 according to CLP Regulation (EC) No. 1272/2008. Based on the Weight of evidence, no classification for acute oral toxicity is not warranted according to CLP Regulation (EC) No. 1272/2008.