Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Short term toxicity to fish:

Based on nominal concentrations, experimental median lethal Concentrations [LC-50 (96 h)] for CAS No. 302-17-0 on Zebra Fish (Denio rario) was found to be > 100 mg/L. This value indicates that the substance2,2,2-trichloroethane-1,1-diol (Chloral hydrate) is not toxic to fish and hence considered as Not classified as per CLP classification criteria.

Short term toxicity to aquatic invertebrate:

The effect concentration (EC50) value was determined to be >98 mg/L for Daphnia magna based on immobilization effect when they were exposed to Chloral hydrate for 48h under static condition. Therefore the EC50 may be considered greater than 100 mg/L for Chloral hydrate. Also this chemical has a harmonized classification that does not indicate the chemical to cause aquatic toxicity.

Thus the substance2,2,2-trichloroethane-1,1-diol (Chloral hydrate) is concluded to be not toxic to aquatic invertebrate and considered as Not classified as per CLP classification criteria.

Long term toxicity to aquatic invertebrate:

In a Long-term toxicity to aquatic invertebrates study for Chloral hydrate in Daphnia magna when they were exposed for 21 days under semi -static condition, the Median lethal concentration LC50 was found to be >96.2mg/l at inhibition in breeding effect, whereas effect concentration (EC50) were found to be 65 mg/l based on inhibition in breeding (at 95% confidence limit is 53.8 to 81.9 mg/l) while low effect concentration (LOEC) on the cumulative survival production litter size was found to be 23.6 mg/l. And NOEC was found to be 11.5 mg/l based on survival and litter size.

Toxicity to aquatic algae and cyanobacteria:

After 72 hours of exposure to various nominal test concentrations of disodium 2,2,2-trichloroethane-1,1-diol (CAS No. 302-17-0) to freshwater green alga Chlorella vulgaris, EC50 was found to be >200 mg/l graphically through probit analysis.

This value indicates that the substance2,2,2-trichloroethane-1,1-diol (Chloral hydrate) is not toxic to aquatic algae and hence considered as Not classified as per CLP classification criteria.

Toxicity to microorganisms:

EC0 was found to be <79mg/l for Chloral hydrate in Entosiphon sulcatum when it was exposed for 72 h. Since there was no inhibition in cell multiplication, EC0 was considered to be equivalent to NOEC and the value for the same was considered to be 79 mg/L. Thus the substance 2,2,2-trichloroethane-1,1-diol (Chloral hydrate) can be concluded to be non toxic to microorganisms.

Additional information

Short-term toxicity to fish:

Two different experimental studies were reviewed for short term toxicity to fish for the test substance 2,2,2-trichloroethane-1,1-diol (Chloral hydrate). The same is presented below as key and supporting studies:

In key study, Fish Acute Toxicity test according to OECD Guideline 203 was conducted for2,2,2-trichloroethane-1,1-diol. The nominal concentration selected for the experiment were 6.25 mg/L, 12.5mg/L,25mg/L, 50mg/L, 100mg/L and Zebra Fishes (Denio rario) were exposed to these concentration for 96 hours. The lethal concentrations i.e. LC50 value was determined to be > 100mg/L.

While in supporting study obtained from J-check database, the lethal concentration (LC50) value of Chloral hydrate in fish (Oryzias latipes) in a 96 hr study on mortality effect was found to be >96 mg/L. Therefore the LC50 may be considered greater than 100 mg/L for Chloral hydrate. Also this chemical has a harmonized classification that does not indicate the chemical to cause aquatic toxicity.

Hence considering the key study value and harmonized classifcation, the substance2,2,2-trichloroethane-1,1-diol (Chloral hydrate) is concluded to be not toxic to fish and hence considered as Not classified as per CLP classification criteria.

Short-term toxicity to aquatic invertebrates:

Experimental and predicted values for short term toxicity to aquatic invertebrate of the target substance 2,2,2-trichloroethane-1,1-diol (Chloral hydrate; CAS No. 302 -17 -0) along with the data for its read across substance 2,2,2-trichloroethanol (Cas No.115-20-8) were reviwewd and same are presented below as weight of evidence approach:

In experimental study, the effect concentration (EC50) value was determined to be >98 mg/L for Daphnia magna based on immobilization effect when they were exposed to Chloral hydrate for 48h under static condition. Therefore the EC50 may be considered greater than 100 mg/L for Chloral hydrate. Also this chemical has a harmonized classification that does not indicate the chemical to cause aquatic toxicity.

In supporting weight of evidence data from Gestis database, 48 hrs short term toxicity of the substance chloral hydarate was determined for Crustaceans. 50% effective concentration (EC50) value of the test substance chloral hydrate was determined to be 500mg/L for crustaceans after 48 hrs of exposure.

While based on the prediction done by EPI suite, ECOSAR version 1.1, on the basis of similarity of structure to chemicals for which the aquatic toxicity has been previously measured by structure-activity relationships (SARs) program,the LC50 value for short term toxicity to aquatic invertebrates was predicted to be 557.918 mg/l 2,2,2-trichloroethane-1,1-diol (Chloral hydrate) in 48 hrs.

Further data obtained from ECOTOX database, short term toxicity to aquatic invertebrates was performed in Ceriodaphnia reticulata (Water Flea) for 48 hrs with <24 hrs age at Larva(e) stage (1ST INSTAR) Test in fresh water media for read across substance 2,2,2-trichloroethanol (Cas No.115-20-8). After the experiment, the EC 50 value for 2,2,2-trichloroethanol (Cas no.115-20-8) was determined to be 190 mg/l on the basis of intoxication.

Thus considering harmonized classification and applying weight of evidence approach, the substance 2,2,2-trichloroethane-1,1-diol (Chloral hydrate) is concluded to be not toxic to aquatic invertebrate and considered as Not classified as per CLP classification criteria.

Long-term toxicity to aquatic invertebrates:

In a Long-term toxicity to aquatic invertebrates study for Chloral hydrate in Daphnia magna when they were exposed for 21 days under semi -static condition, the Median lethal concentration LC50 was found to be >96.2mg/l at inhibition in breeding effect, whereas effect concentration (EC50) were found to be 65 mg/l based on inhibition in breeding (at 95% confidence limit is 53.8 to 81.9 mg/l) while low effect concentration (LOEC) on the cumulative survival production litter size was found to be 23.6 mg/l. And NOEC was found to be 11.5 mg/l based on survival and litter size.

Considering the NOEC value it is concluded that the test substance Cloral hydrate does not considered for long term aquatic toxicity.

Toxicity to aquatic algae and cyanobacteria:

Different experimental studies of the substance2,2,2-trichloroethane-1,1-diol (Chloral hydrate) were reviwed for the toxicity aquatic algae and cyanobacteriaendpoint. The same is summarised below as key and supporting studies:

In key study, the effect of test item2,2,2-trichloroethane-1,1-diol, CAS No. 302-17-0 was studied on the growth of fresh water green alga Chlorella vulgaris. The study was conducted following OECD guideline 201- Alga growth inhibition test. The test concentration chosen for the study were 6.25mg/l, 12.5mg/l, 25mg/l, 50 mg/l, 100mg/l and 200 mg/l. The test concentrations were prepared using stock solution of the test item using mineral media. The green alga was exposed to the test concentration for a period of 72 hours to observe average specific growth rate and % growth inhibition under the effect of the test item. EC50 calculated graphically through probit analysis was observed to be >200 mg/l.

While in the supporting data obtained from J-check database, the growth rate concentration (ErC50) value of Chloral hydrate in aquatic algae (Scenedesmus quadricauda) in 72 hrs on the basis of growth effect was found to be >95 mg/l .And no observed effect concentration for growth rate (NOECr) was found to be 15 mg/l. Therefore the EC50 may be considered greater than 100 mg/L for Chloral hydrate. Also this chemical has a harmonized classification that does not indicate the chemical to cause aquatic toxicity.

Further supporting data from peer reviewed journal indicates the effective concentration (EC0) value based on analogous methods of the cell multiplication inhibition test of Chloral hydrate in aquatic algae (Scenedesmus quadricauda) in 7 days was determined to be 2.8 mg/l.

Hence considering the key study value and harmonized classification, the substance 2,2,2-trichloroethane-1,1-diol (Chloral hydrate) is concluded to be not toxic to aquatic algae and hence considered as Not classified as per CLP classification criteria.

Toxicity to microorganisms:

Two studies on two different microorganisms were reviewed for the substance2,2,2-trichloroethane-1,1-diol (Chloral hydrate) for the same peer reviewed journal. The same are represented below as key and supporting studies:

In key toxicity to microorganism study for Chloral hydrate the biological effect was evaluated. By using analogous methods of the cell multiplication inhibition test, the toxicity threshold (TT) of chloral hydrate was determined to be 79 mg/l for Entosiphon sulcatum. Therefore EC0 was considered to be <79mg/l for 72h for Entosiphon sulcatum.

 

While in supporting toxicity to microorganisms study for Chloral hydrate the biological effect was evaluated. By using analogous methods of the cell multiplication inhibition test, the toxicity threshold (TT) of chloral hydrate was determined to be 1.6 mg/l for bacteria Pseudomonas putida. Therefore EC0 was considered to be 1.6 mg/l for 16 h for Pseudomonas putida.

Considering the EC0 values i.e. no effects observed on cell multiplication of both the species the substance2,2,2-trichloroethane-1,1-diol (Chloral hydrate) can be concluded to be non toxic to microorganisms.