Potassium iodide

Endpoint summary

Description of key information

Short term toxicity to fish:

Short term toxicity of test chemical were carried out on the Danio rerio (previous name: Brachydanio rerio). Test conducted in accordance with OECD Guideline 203 (Fish, Acute Toxicity Test). The limit test at 100 mg/L was conducted. The test solution was prepared by dissolving 1 g of the test substance in 10 liters deionized water with continuous stirring test water. Deionized water was used. Observations (mortality, visible symptoms, pH, Temperature, dissolved oxygen content) were recorded after 24 hours, 48 hours, 72 hours and 96 hours of the start of the experiment. The test vessels used were all glass bowl aquaria of 12” each. 3-4 months old 8 fishes in each vessel were added. In a 96 h study for test chemical on Danio rerio, at a test concentration of 100 mg/L, the fishes were found to be freely swimming in the bowl aquaria without showing any abnormal symptoms. No mortalities were observed at the test concentration of 100 mg/l. No mortalities were observed in the control aquaria. Based on the mortality of Danio rerio (previous name: Brachydanio rerio) by the test chemical after 96 hrs of exposure, LC50 was observed to be > 100 mg/l. As no effect were observed at 100 mg/l test extended for 7 days. After 7 days of exposure no effect were observed. Thus on the basis of LC50 > 100 mg/l, chemical consider to be nontoxic and can be consider to be not classified as per the CLP classification criteria.

Long term toxicity to fish:

Based on the prediction done using ECOSAR version 1.1, the long term toxicity on fish was predicted for test substance. On the basis of no effects observed in a semi-static freshwater fish, the NOEC value for the substance is estimated to be 66.356 mg/l for fish for 28 days of exposure duration. Based on this value, it can be concluded that the test chemical can be considered as non-toxic to fish at environmentally relevant concentrations and can be considered to be not- classified as per the CLP classification criteria. 

Short term toxicity of aquatic invertebrate:

The study was conducted to determine the effect of test chemical on Dreissena polymorpha. Test conducted under the static system on 1.5-2.0 cm old freshwater Dreissena polymorpha. 24 hrs of exposure period were provided. The lethal concentration (LC50) value of test chemical on aquatic invertebrates (Dreissena polymorpha) in a 24 hrs study by observing effect on mortality was determine to be 226 mg/L. Based on the LC50 value, chemical consider to be nontoxic and can be consider to be not classified as per the CLP classification criteria.

Long term toxicity of aquatic invertebrate:

Based on the prediction done using ECOSAR version 1.1, the long term toxicity on aquatic invertebrates was predicted for test substance. On the basis of no effects observed on a freshwater aquatic invertebrates, the NOEC value for the substance is estimated to be 29.870 mg/l for daphnia for 21 days of exposure duration. Based on this value, it can be concluded that the test chemical can be considered as non-toxic to daphnia at environmentally relevant concentrations and can be considered not-classified as per the CLP classification criteria. 

Toxicity to aquatic algae and cyanobacteria:

To evaluate toxicity of test chemical on the growth of Dunaliella salina. Saltwater Dunaliella salina were used as a test organism which exposed for the 10 days of incubation. Serial concentrations of test chemical were supplemented into the modified medium for the culture of Dunaliella salina. The inocula, each containing 3 × 10(4) alga cells, were added to 10mL of the corresponding media and incubated in an oscillator shaker at a rate of 150 rpm under light irradiation of 81.04μmolm−2 s−1 and a 12 h/12 h light/dark cycle. Minimum Inhibitory Concentration (MIC100) value of test chemical in green algae (Dunaliella salina) in a 10 days. study on growth effect was determine to be 356.8 mg/L.Thus considering CLP Criteria for aquatic classification of the substance, it is concluded that test chemical does not exhibit toxicity to green algae (Dunaliella salina).

Toxicity to microorganisms:

In this study the effects of test chemical on the growth and metabolite accumulation of Staphylococcus auerus (JKB068) and Escherichia coli (JKE029). MIC100 values were determined as the minimum concentration of test chemical that inhibited the growth of the organism. Minimum Inhibitory Concentration (MIC100) value of test chemical in microorganism (Staphylococcus auerus) in a 24hrs. study on growth effect was determine to be 358.3 ± 17.1 mg/L and Minimum Inhibitory Concentration (MIC100) value of test chemical on microorganism (Escherichia coli) in a 24 hrs study on growth effect was determine to be 219.4 ± 9.6 mg/L.

 

Additional information

Summarized study results for the toxicity of test chemical on the growth and other behavior of test organisms fish, invertebrates, algae, cyanobacteria and microorganisms. The studies are as mentioned below:

 

Short term toxicity to fish:

Data available for the test chemicals including structurally and functionally similar read across chemicals, study has been reviewed to determine the short term toxicity on fish of the test chemical. The studies are as mentioned below:

 

In the first study short term toxicity of test chemical were carried out on the Danio rerio (previous name: Brachydanio rerio). Test conducted in accordance with OECD Guideline 203 (Fish, Acute Toxicity Test). The limit test at 100 mg/L was conducted. The test solution was prepared by dissolving 1 g of the test substance in 10 liters deionized water with continuous stirring test water. Deionized water was used. Observations (mortality, visible symptoms, pH, Temperature, dissolved oxygen content) were recorded after 24 hours, 48 hours, 72 hours and 96 hours of the start of the experiment. The test vessels used were all glass bowl aquaria of 12” each. 3-4 months old 8 fishes in each vessel were added. In a 96 h study for test chemical on Danio rerio, at a test concentration of 100 mg/L, the fishes were found to be freely swimming in the bowl aquaria without showing any abnormal symptoms. No mortalities were observed at the test concentration of 100 mg/l. No mortalities were observed in the control aquaria. Based on the mortality of Danio rerio (previous name: Brachydanio rerio) by the test chemical after 96 hrs of exposure, LC50 was observed to be > 100 mg/l. As no effect were observed at 100 mg/l test extended for 7 days. After 7 days of exposure no effect were observed. Thus on the basis of LC50 > 100 mg/l, chemical consider to be nontoxic and can be consider to be not classified as per the CLP classification criteria.

 

Above study was supported by the second study. Short term toxicity of test chemical were determine on the growth of fishes Oncorhynchus mykiss (previous name: Salmo gairdneri). Test conducted under the static system for 96 hrs. The lethal concentration (LC50) value of test chemical on fish (Oncorhynchus mykiss) in a 96 hrs study on mortality effect was determine to be 2190 mg/L. Thus considering CLP Criteria for aquatic classification of the substance, it is concluded that the test chemical does not exhibit short term toxicity to fish (Oncorhynchus mykiss).

 

In the third study from secondary source short term toxicity of test chemical were determine on the growth of fish Oncorhynchus mykiss (previous name: Salmo gairdneri). Test conducted under the static system on 50 MM Oncorhynchus mykiss. 96 hrs of incubation were provided to the fishes. After the exposure of test chemical with Oncorhynchus mykiss (previous name: Salmo gairdneri) for 96 hrs, LC50 was observed to be 896 mg/l. Based on the LC50 value, chemical consider to be nontoxic and not classified as per the CLP classification criteria.

 

Long term toxicity to fish:

Based on the prediction done using ECOSAR version 1.1, the long term toxicity on fish was predicted for test substance. On the basis of no effects observed in a semi-static freshwater fish, the NOEC value for the substance is estimated to be 66.356 mg/l for fish for 28 days of exposure duration. Based on this value, it can be concluded that the test chemical can be considered as non-toxic to fish at environmentally relevant concentrations and can be considered to be not- classified as per the CLP classification criteria. 

 

Short term toxicity of aquatic invertebrate:

Data available for test chemicals including structurally and functionally similar read across chemical, study has been reviewed to determine the short term toxicity of the test chemical on the growth and mobility of daphnia magna. The studies are as mentioned below:

The first study was conducted to determine the effect of test chemical on Dreissena polymorpha. Test conducted under the static system on 1.5-2.0 cm old freshwater Dreissena polymorpha. 24 hrs of exposure period were provided. The lethal concentration (LC50) value of test chemical on aquatic invertebrates (Dreissena polymorpha) in a 24 hrs study by observing effect on mortality was determine to be 226 mg/L. Based on the LC50 value, chemical consider to be nontoxic and can be consider to be not classified as per the CLP classification criteria.

 

First study was supported by the second study from experimental report. The study was designed to assess the toxic effects of the test compound on the test Daphnids. Beaker containing 20ml of media with 10 Daphinds. A static procedure was used for the study and it was conducted in compliance with the OECD guideline 202. The test substance was soluble in water. Therefore, the test solution was prepared by dissolving 2 mg of the test substance in 20 ml of ADaM’s media. Achieving test concentrations of 100 mg/L, respectively. The test concentrations selected for the study was 100 mg/L. The test vessels used were all glass beaker having the water capacity of 25ml, in each vessel 10 daphnia were incorporated. Observations (immobility, pH, Temperature, dissolved oxygen content) were recorded after 24 and 48hours of the start of the experiment. Based on nominal concentrations, experimental median effective Concentrations [EC-50 (48 h)] for test chemical on freshwater daphnia magna was determine to be 100 mg/L. This value indicates that the substance is likely to be nonhazardous to aquatic invertebrate and cannot be classified as per the CLP criteria.

 

Similar study was conducted to investigate the effect of test chemical on the growth of daphnia magna. Study conducted according to the ISO 6341 15 "Water quality – Determination of the inhibition of the mobility of Daphnia magna Straus (Cladocera, Crustacea)". Test chemical exposed with the daphnia magna for 48 hrs. After the exposure of test chemical with the daphnia magna for 48 hrs, EC0 no effect were observed on the mobility at the concentration 940 mg/l. Thus on the basis of above result it can be concluded that the chemical was nontoxic and not classified as per the CLP classification criteria.

 

Thus based on the above results, chemical consider to be nontoxic and thus not classified as per the CLP classification criteria.

 

Long term toxicity of aquatic invertebrate:

Based on the prediction done using ECOSAR version 1.1, the long term toxicity on aquatic invertebrates was predicted for test substance. On the basis of no effects observed on a freshwater aquatic invertebrates, the NOEC value for the substance is estimated to be 29.870 mg/l for daphnia for 21 days of exposure duration. Based on this value, it can be concluded that the test chemical can be considered as non-toxic to daphnia at environmentally relevant concentrations and can be considered not-classified as per the CLP classification criteria. 

 

Toxicity to aquatic algae and cyanobacteria:

Data available for the test chemicals, study has been reviewed to determine the short term toxicity on growth of algae and cyanobacteria of the test chemical. The studies are as mentioned below:

To evaluate toxicity of test chemical on the growth of Dunaliella salina. Saltwater Dunaliella salina were used as a test organism which exposed for the 10 days of incubation. Serial concentrations of test chemical were supplemented into the modified medium for the culture of Dunaliella salina. The inocula, each containing 3 × 10(4) alga cells, were added to 10mL of the corresponding media and incubated in an oscillator shaker at a rate of 150 rpm under light irradiation of 81.04μmolm−2 s−1 and a 12 h/12 h light/dark cycle. Minimum Inhibitory Concentration (MIC100) value of test chemical in green algae (Dunaliella salina) in a 10 days. study on growth effect was determine to be 356.8 mg/L.Thus considering CLP Criteria for aquatic classification of the substance, it is concluded that test chemical does not exhibit toxicity to green algae (Dunaliella salina).

 

In the second study the effects of chemical on the growth and metabolite accumulation of Chlorella sp. were investigated to assess its possible application to the mass culture of the two diatoms in open environment, extensive systems. Test conducted under the static system for 10 days brackish water Chlorella sp. maintain under the proper conditions of temperature and pH. Serial concentrations of test chemical were supplemented into the f/2 medium for Chlorella sp. At concentrations >700 mg/l, the growth of Chlorella sp. was inhibited. Minimum Inhibitory Concentration (MIC100) of test chemical in green algae (Chlorella sp.) in a 10 days study on growth effect was observed to be 696.2 ± 9.4 mg/L. Thus considering CLP Criteria for aquatic classification of the substance, it is concluded that the test chemical does not exhibit toxicity to green algae (Chlorella sp.) and thus not classified.

 

Above results were supported by another study from peer reviewed journal. Aim of this study was to determine the effect of test chemical on the growth of Cryptomonas sp. Test conducted under the static system for the total exposure period of 10 days. Minimum Inhibitory Concentration (MIC100) value of test chemical in green algae (Cryptomonas sp.) in a 10 days study on growth effect was determine to be 475.9 ± 10.3 mg/L. Thus considering CLP Criteria for aquatic classification of the substance, it is concluded that the test chemical does not exhibit toxicity to green algae (Cryptomonas sp) and thus not classified as per the classification criteria.

 

Thus based on the above results, chemical consider to be nontoxic and not classified as per the CLP classification criteria.

 

Toxicity to microorganisms:

Data available for the test chemicals, study has been reviewed to determine the short term toxicity on growth of microorganisms of the test chemical. The studies are as mentioned below:

In the first study from peer reviewed journal the effects of test chemical on the growth and metabolite accumulation of Staphylococcus auerus (JKB068) and Escherichia coli (JKE029). MIC100 values were determined as the minimum concentration of test chemical that inhibited the growth of the organism. Minimum Inhibitory Concentration (MIC100) value of test chemical in microorganism (Staphylococcus auerus) in a 24hrs. study on growth effect was determine to be 358.3 ± 17.1 mg/L and Minimum Inhibitory Concentration (MIC100) value of test chemical on microorganism (Escherichia coli) in a 24 hrs study on growth effect was determine to be 219.4 ± 9.6 mg/L.

 

First study was supported by the second study. Aim of this study was to determine the effect of test chemical on the growth of microorganism. Minimum Inhibitory Concentration were checked after the 24 hrs. Nutrient agar plates containing various concentrations of chemical were prepared in quintuplicate. The above mentioned organisms were inoculated by standardized loops. Minimum Inhibitory Concentration (MIC100) value of test chemical on microorganism (Bacillus subitilis) in a 24hrs study on growth effect was determine to be 147.6 ± 10.2mg/L. Thus chemical consider to be nontoxic.

 

Similar study was conducted to determine the effect of test chemical on the growth and mortality of test organisms Clostridium species. Nutrient agar plates containing various concentrations of potassium iodide were prepared in quintuplicate. The two Clostridium species that had been isolated from the cultures of N. closterium and P. tricornutum, were inoculated by standardized loops. MIC100 values were determined as the minimum concentration of test chemical that inhibited the growth of the organism. Test conducted for 24 hrs. Inhibition observed at 231.5 mg/l and 200.9 mg/l on 2nd species.

 

Thus based on the above results, chemical toxicity ranges from 147 mg/l to 231.5 mg/l.