4,7-dichloroquinoline

Endpoint summary

Description of key information

Short term toxicity to fish:

Prediction done using average value of both models i.e Leadscope and SciMatics SciQSAR model and the result were predicted in Battery model. Based on the QSAR prediction done using the Danish (Q)SAR Database, the 96 hours LC50 was estimated to be 5.147 mg/l on Pimephales promelas for tested substance with mortality effects. Thus based on this (LC50) value, it can be concluded that the substance can be classified as toxic in the category of aquatic chronic 2 as per the criteria of CLP regulation.

Short term toxicity to aquatic invertebrates:

An acute immobilisation test was conducted for 48 hrs for assessing the short term toxicity of test chemical to aquatic invertebrate. Study was performed according to the OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test). Daphnia magna was used a test organism. The stock solution 1.0 g/l  was prepared in acetone. Test solutions of required concentrationas were prepared by mixing the stock solution of the test sample with reconstituted test water. 0.06 , 0.12 , 0.24 , 0.50 , 1.00 , 2.00 mg/l, respectively nominal concentrations were used in the study. Effects on immobilisation were observed for 48 hours and conducted under the static system. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration EC50 was calculated using nonlinear regression by the software Prism 4.0. Based on the immobilisation of Daphnia magna due to the exposure of test chemical for 48 hours, the EC50 value was determine to be 1.84 mg/l. EC50 value indicates that the substance is likely to be hazardous to aquatic invertebrates and can be consider to be classified in aquatic chronic 2 category as per the CLP criteria.

Toxicity to aquatic algae:

Principle of this study was to evaluate the nature of test chemical when comes in contact with the test organism. Test was conducted according to the OECD guideline 201. Desmodesmus subspicatus (previous name: Scenedesmus subspicatus) was used as test organism. The stock solution 10.0 g/l was prepared in acetone. Test solutions of required concentrations were prepared by mixing the stock solution of the test sample with OECD growth medium and inoculum culture. 0.6 , 1.2 . 2.4 , 5.0 , 10.0 mg/l, respectively concentrations were used. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration EC50 was calculated using nonlinear regression by the software Prism 4.0. Effect on the growth of algae was determined after an exposure period of 72 hrs. The median effective concentration (EC50) of the test substance on algae was determined to be 9.8 mg/L with 95% CI of 9.6 mg/l to 9.9 mg/l on the basis of growth rate inhibition effects in a 72 hour study. Based on the ErC50 value, the substance chemical was consider likely to be hazardous to aquatic algae and can be consider to be classified in aquatic chronic 2 category as per the CLP classification criteria.

Toxicity to microorganisms:

As the study was conducted on two different organisms, effects were measured on the basis of different parameter. Based on the population growth rate inhibition of microorganisms Tetrahymena thermophila (Ciliate Protozoa), due to the test chemical exposure for 48 hours, the EC50 value was determined to be 25.5 mg/l. Also based on the inhibition of luminescence Photobacterium phosphoreum, due to the test chemical exposure for 15 minutes, the EC50 value was determined to be 3.29 mg/l. Thus on the basis of above all studies, the EC50 value ranges from 3.29 to 25.5 mg/l.

Additional information

Short term toxicity to fish:

Based on the various predicted data and experimental studies from different sources including secondary databases, authoritative database and study reports were reviewed for the evaluation of the effects of test chemical and structurally and functionally similar read across chemicals on the mortality of fishes. The studies are as mentioned below:

Prediction done using average value of both models i.e Leadscope and SciMatics SciQSAR model and the result were predicted in Battery model. Based on the QSAR prediction done using the Danish (Q)SAR Database, the 96 hours LC50 was estimated to be 5.147 mg/l on Pimephales promelas for tested substance with mortality effects. Thus based on this (LC50) value, it can be concluded that the substance can be classified as toxic in the category of aquatic chronic 2 as per the criteria of CLP regulation.

Based on the prediction done by EPI suite, 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 fish was predicted. On the basis of this program, the LC 50 value for short term toxicity to fish was predicted to be 8.427 mg/l for test chemical in 96 hrs. Based on this value it can be concluded that the substance is considered to be toxic to aquatic environment and can be classified in aquatic chronic 2 category as per the criteria mentioned in CLP regulation.

Above data further supported by the third weight of evidence study from authoritative database. Principle of this study was to determine the short term toxicity of test chemical on the mortality rate of fishes. Test conducted under the static system for 96 hours. Based on the mortality of fishes due to the test chemical exposure, the LC50 value was determined to be 2.5 mg/l. Based on the LC50 value, test chemical consider to be toxic and can be consider to be classified in aquatic chronic category 2 as per the CLP classification criteria.

Similar study was conducted to determine the effect of test chemical on the mortality of fishes. Oryzias latipes (Japanese Medaka Medaka) was used as test organism. Test conducted under the static system for 96 hours. Based on the mortality of fishes Oryzias latipes (Japanese Medaka Medaka), due to the test chemical exposure for 96 hours, the LC50 value was observed to be 6.4 mg/l with 95% CI of 3.3 mg/l to 11 mg/l.

Thus based on the above all studies and effects observations, it was concluded that the test chemical was toxic and classified in aquatic chronic category 2 as per the CLP classification criteria.

Short term toxicity to aquatic invertebrates:

Based on the various experimental studies from different sources including secondary databases, authoritative database and studies were reviewed for the evaluation of the effects of test chemical and structurally and functionally similar read across chemicals on the immobility of aquatic invertebrates. The studies are as mentioned below:

An acute immobilisation test was conducted for 48 hrs for assessing the short term toxicity of test chemical to aquatic invertebrate. Study was performed according to the OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test). Daphnia magna was used a test organism. The stock solution 1.0 g/l  was prepared in acetone. Test solutions of required concentrationas were prepared by mixing the stock solution of the test sample with reconstituted test water. 0.06 , 0.12 , 0.24 , 0.50 , 1.00 , 2.00 mg/l, respectively nominal concentrations were used in the study. Effects on immobilisation were observed for 48 hours and conducted under the static system. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration EC50 was calculated using nonlinear regression by the software Prism 4.0. Based on the immobilisation of Daphnia magna due to the exposure of test chemical for 48 hours, the EC50 value was determine to be 1.84 mg/l. EC50 value indicates that the substance is likely to be hazardous to aquatic invertebrates and can be consider to be classified in aquatic chronic 2 category as per the CLP criteria.

Above study further supported by the second study from authoritative database. Aim of this study was to assess the short term toxicity of test chemical to aquatic invertebrates. Study was performed according to the OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test). Daphnia magna was used as a test organism. Test chemical was analytically monitorized by HPLC method. 0, 1.0, 1.8, 3.2, 5.6, 10 mg/L respectively concentrations were used in the study. Test conducted under the static system on Juvenile (Less than 24 hours after birth) for 48 hours. Based on the effects observation on the mobility of Daphnia magna due to the test chemical exposure for 48 hours, the E50 value was determined to be 2.4 mg/l. This EC50 value indicates, that the test chemical was toxic to the aquatic invertebrate Daphnia magna and thus can be consider to be classified in aquatic chronic category 2 as per the CLP classification criteria.

Principle of this third weight of evidence study was to determine the short term toxicity of test chemical to aquatic invertebrates. Daphnia magna was used as a test organism. Syudy was performed under the static systme for 48 hours. (6 - 24) hours old Daphnia magna was used in the study which was collected from the laboratory. Based on the immobility of Daphnia magna, the EC50 value was observed to be 3.4 mg/l after exposure period of 48 hours, This EC50 value indicates that the test chemical was toxic to the aquatic invertebrate Daphnia magna and thus can be consider to be classified in aquatic chronic category 2 as per the CLP classification criteria.

Thus based on the above all studies and effects observations, it was concluded that the test chemical was toxic and classified in aquatic chronic category 2 as per the CLP classification criteria.

Toxicity to aquatic algae:

Based on the various experimental studies from different sources including secondary databases, authoritative database and studies were reviewed for the evaluation of the effects of test chemical and structurally and functionally similar read across chemicals on the growth of algae. The studies are as mentioned below:

Principle of this study was to evaluate the nature of test chemical when comes in contact with the test organism. Test was conducted according to the OECD guideline 201. Desmodesmus subspicatus (previous name: Scenedesmus subspicatus) was used as test organism. The stock solution 10.0 g/l was prepared in acetone. Test solutions of required concentrations were prepared by mixing the stock solution of the test sample with OECD growth medium and inoculum culture. 0.6 , 1.2 . 2.4 , 5.0 , 10.0 mg/l, respectively concentrations were used. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration EC50 was calculated using nonlinear regression by the software Prism 4.0. Effect on the growth of algae was determined after an exposure period of 72 hrs. The median effective concentration (EC50) of the test substance on algae was determined to be 9.8 mg/L with 95% CI of 9.6 mg/l to 9.9 mg/l on the basis of growth rate inhibition effects in a 72 hour study. Based on the ErC50 value, the substance chemical was consider likely to be hazardous to aquatic algae and can be consider to be classified in aquatic chronic 2 category as per the CLP classification criteria.

Above study further supported by the seconfd study from authoritative database. Principle of this study was to determine the effect of test chemical on the growth of green algae. Chlorella vulgaris was used as a test organism. Test conducted under the static system for 96 hours. Effects were measured on the basis of growth rate inhibition of algae. Exponential growth phase algae were exposed with test chemical. Based on the growth rate inhibition of green algae Chlorella vulgaris, due to the test chemical exposure for 96 hours, the EC50 value was determined to be 9.7 mg/l.

Principle of this third study was to determine the effect of test chemical on the growth of aquatic algae. Anacystis aeruginosa (Blue green algae) was used as a test organism. Test conducted under the static system for 24 hours. After the exposure period of 24 hours, 0% survival of algae was observed. Based on the mortality rate of Blue green algae Anacystis aeruginosa, due to the test chemical exposure for 24 hours, the EC100 value was observed to be at 5 mg/l.

Thus based on the above all studies and effects observations, it was concluded that the test chemical was toxic and classified in aquatic chronic category 2 as per the CLP classification criteria.

Toxicity to microorganisms:

Based on the various experimental studies from different sources, studies were reviewed for the determination of effects of test chemical and structually and functionally similar read across chemicals on the growth of microorganisms and the studies are as mention below:

Principle of this study from secondary source was to determine the effect of test chemical on the population growth rate inhibition of microorganisms Tetrahymena thermophila (Ciliate Protozoa). Test conducted under the static system for 48 hours. After the exposure period of 48 hours, effects on the population growth was observed and noted. Based on the population growth rate inhibition of microorganisms Tetrahymena thermophila (Ciliate Protozoa), due to the test chemical exposure for 48 hours, the EC50 value was determined to be 25.5 mg/l.

Above study further supported by the weight of evidence data from secondary sources. Principle of this study was to determine the effect of test chemical on the luminescence of Photobacterium phosphoreum. Test conducted for 15 minutes. Based on the inhibition of luminescence Photobacterium phosphoreum, due to the test chemical exposure for 15 minutes, the EC50 value was determined to be 3.29 mg/l.

As the study was conducted on two different organisms, effects were measured on the basis of different parameter. Based on the population growth rate inhibition of microorganisms Tetrahymena thermophila (Ciliate Protozoa), due to the test chemical exposure for 48 hours, the EC50 value was determined to be 25.5 mg/l. Also based on the inhibition of luminescence Photobacterium phosphoreum, due to the test chemical exposure for 15 minutes, the EC50 value was determined to be 3.29 mg/l. Thus on the basis of above all studies, the EC50 value ranges from 3.29 to 25.5 mg/l.

Thus based on the overall studies and effects observations on the fishes, invertebrates, algae and cyanobacteria, test chemical was consider to be toxic and classified in aquatic chronic category 2 as per the CLP classification criteria.