Reaction mass of tetramethylammonium hypochlorite and tetramethylammonium chloride

Endpoint summary

Description of key information

Oral:
There are two studies available for acute oral toxicity for the target substance (Halo Salt) and one study for approximately 1:2 water diluted mixture of the target substance (trade name CLK-222). CLK-222 is the only formulation marketed and used in the EU.
The oral LD50 (rat) is > 300 mg/kg bw for Halo Salt
The oral LD50 (rat) is > 300 mg/kg bw for CLK-222 (water solution of Halo Salt)
The oral LD50 (rat) is 50 - 300 mg/kg bw for Halo Salt
Inhalation:
Not relevant route of human exposure
Dermal:
Not relevant route of human exposure

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

July 9, 2014 - August 11, 2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study is conducted according to the current guideline and in compliance with GLP:

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

other: Crl:CD(SD)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories, Inc., Kingston, NY
- Age at study initiation: 9-10 weeks old
- Weight at study initiation: 179g to 212g
- Fasting period before study: overnight
- Housing: All rats were housed individually in clean, stainless steel, wire-mesh cages suspended above cage-board until euthanasia.
- Diet (e.g. ad libitum): PMI Nutrition International, LLC, Certified Rodent LabDiet® 5002 ad libitum throughout the acclimatisation period and during the study except overnight period prior to dosing
- Water (e.g. ad libitum): Municipal water ad libitum throughout the acclimatisation period and during the study except overnight period prior to dosing
- Acclimation period: minimumoof 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 71°F ± 5°F (22°C ± 3°C)
- Humidity (%): 50% ± 20%
- Air changes (per hr): 10 fresh air changes per hour
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES:
20-JUL-2014 Animals fasted
21-JUL-2014, 24-JUL-2014, 28-JUL-2014 Test article administration
11-AUG-2014 Last necropsy

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

For the 300 mg/kg group, the test substance was dosed undiluted. The dose volume of 0.29 mL/kg.

For the 50 mg/kg group, the test substance was dosed at a diluted concentration of 5 mg/mL. The dose volume of 10 mL/kg.

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: The recent toxicity information from 10-D dose range finding study shows that the substance caused mortality (one rat died at study day 1, 3, 4) when dosed repeatedly at 200 mg/kg bw (Baracani, R. (2014).

Doses:

300 mg/kg bw, 50 mg/kg bw

No. of animals per sex per dose:

3 females / dose (300mg/kg) and 6 (3+3) females / dose (50mg/kg)

Control animals:

no

Details on study design:

All 3 females at 300 mg/kg died. Therefore, 3 females were dosed at 50 mg/kg. No mortality was observed, and 3 additional females were dosed at 50 mg/kg. Again, no mortality was observed, and therefore, no additional rats were dosed.

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The rats were observed at approximately 15 minutes (± 5 minutes) and 1, 2 and 4 hours post-dosing on study day 0 and twice daily, once in the morning and once in the afternoon.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight,organ weights

Sex:

female

Dose descriptor:

LD50

Effect level:

> 50 - < 300 mg/kg bw

Based on:

test mat.

Remarks on result:

other: mortality

Mortality:

300 mg/kg 3/3
50 mg/kg 0/6

Clinical signs:

other: There were no clinical observations for the 50 mg/kg group females.

Gross pathology:

There were no test substance-related macroscopic findings. One female in the 300 mg/kg group that died had clear uterine contents.

Other findings:

- Organ weights: not measured
- Histopathology: not done
- Potential target organs: not found
- Other observations: not done

Interpretation of results:

Toxicity Category III

Remarks:

Migrated information This study result is used for a classification Criteria used for interpretation of results: EU

Conclusions:

Fasted female albino rats were administered with HaloSalt once orally via gavage. The estimated LD50 of Halo Salt was greater than 50 mg/kg but less than 300 mg/kg.

Executive summary:

The objectives of this study were to determine the estimated acute oral median lethal dose and evaluate potential systemic toxicity of the test substance when administered as a single dose to albino rats.

The study is considered reliable without restrictions since the study is carried out according to OECD No. 423 guideline and in compliance with principles of Good Laboratory Paractice (GLP).

Based on the results of this study, the estimated LD50 of Halo Salt was greater than 50 mg/kg but less than 300 mg/kg when administered once orally via gavage to fasted female albino rats (Acute Tox. 3).

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

50 mg/kg bw

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Data waiving:

exposure considerations

Justification for data waiving:

other:

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Additional information

Oral exposure

There are three guideline compliant acute toxicity studies via oral route conducted for the target substance. The studies by Weinberg, J.T. 2014 and DiDonato, L.J. 2009a are conducted to the target substance itself (trade name Halo Salt) and the study by DiDonato, L.J. 2009b is conducted for the diluted form of the target substance (trade name CLK-222). CLK-222 is approximately 1:2 water dilution of Halo Salt and the only formulation marketed and used in the EU.

The acute oral lethal dose (LD50) of the target substance was evaluated in male and female rats (DiDonato, L.J. 2009a). The objective of the study was to determine by oral exposure if a substance is a poisonous material and, if so, to assign the substance to the applicable packing group category, (49 CFR 173.123(a), revised October 1, 2007). The limit value for assignment of a certain substance to a packing group category is 300 mg/kg of body weight. Thus, this substance was tested only using this limit dose. In this study, the LD50 value of the target substance in male and female rats was estimated to be greater than 300 mg/kg of body weight.

The second acute oral toxicity study was conducted for the diluted formulation of the target substance (CLK-222) (DiDonato, L.J. 2009b). The objective of this study was also to assign the substance to the applicable packing group category and the limit value for assignment is 300 mg/kg of body weight. Thus, the study was conducted using 300mg/kg limit dose. The acute oral lethal dose (LD50) of CLK-222 in male and female rats was estimated to be greater than 300 mg/kg of body weight.

Both studies are considered reliable with restrictions. The studies are carried out using the equivalent method to OECD No. 423 guideline and in compliance with principles of Good Laboratory Practice (GLP). However, only one dose level was used.

Based on these results, there is not enough data to conclude if the substance needs to be classified for acute oral toxicity. Further acute oral toxicity study was conducted to assign the substance in an appropriate hazard class (Weinberg, J.T. 2014).

To select the starting dose for the acute toxicity study the most recent data from 10-D dose range finding study was assessed (Baracani, R., 2014). The results showed that the target substance caused mortality (all rats died by study day 4) when dosed repeatedly at 200 mg/kg bw. Thus, 300 mg/kg bw dose was selected for acute toxicity study. 

In a guideline study of Weinberg, J.T. (2014) (OECD 423 - Acute Toxic Class Method) three female rats were gavaged with undiluted test substance at a dose level of 300 mg/kg bw. All 3 females at 300 mg/kg died. Following 48 hours observation, an additional three female animals were given a single oral dose level of 50 mg/kg bodyweight. No mortality was observed, and 3 additional females were dosed at 50 mg/kg. Again, no mortality was observed, and therefore, no additional rats were dosed.

Clinical signs and bodyweight development were monitored during the study. All animals were subjected to gross necropsy. The post exposure period was 14 days. There were no deaths observed during the study and no signs of toxicity were noted. All animals showed expected gains in bodyweight. No abnormalities were noted at necropsy. The acute median lethal dose (LD50) of the test item in female Wistar rat was estimated to be 50 - 300 mg/kg of body weight.

Justification for selection of acute toxicity – oral endpoint
A good quality study conducted for the target substance according to the OECD 423 guideline and in accordance of GLP.

Justification for selection of acute toxicity – inhalation endpoint
Not a likely exposure route, since the target substance has low evaporation rate from aqueous solution.

Justification for selection of acute toxicity – dermal endpoint
Not a likely exposure route. The skin absorption is expected to be negligible due to the polarity of the chlorine species. As the substance is classified as skin corrosive appropriate RMMs are in use to prevent human exposure.

Justification for classification or non-classification

The available data for Halo Salt indicate potential for acute toxicity. Based on the oral LD50 values the substance has to be classified to hazard class Acute Tox 3 H301 (oral) according to CLP Regulation 1272/2008 and T; R25 according to Directive 67/548/EEC.