Sodium iodide

Endpoint summary

Description of key information

Short term toxicity to fish:

This study was designed to assess the acute toxic effects of the test compound on the Zebra fish (Danio rerio). Bowl aquaria containing 10 liters of deionized water were loaded with 8 fishes each. A static procedure was used for the study and it was conducted in compliance with the OECD Guideline 203 (Fish, Acute Toxicity Test). The test solution was prepared by dissolving 1g of the test substance in10 liters deionized water with continuous stirring for achieving the test concentration of 100 mg/L, respectively. The limit test at 100 mg/L was conducted and it was observed that the LC-50 is greater than this concentration. 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. In a 96 h study for test chemical onDanio 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 found in the control aquaria. The LC0 (96 hours) wasobserved at 100 mg/L (highest concentration at which no mortality was observed). LC50 (96 hours) was > 100mg/L.

Long term toxicity to fish:

Based on the prediction done using ECOSAR version, the long term toxicity on fish was predicted for test substance. On the basis of no effects observed in a freshwater system, 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 the growth of fish at environmentally relevant concentrations and can be considered to be not-classified as per the CLP classification criteria. 

 

Short term toxicity to aquatic invertebrates:

Aim of this study was to determine the effect of test chemical on the mortality of daphnia magna. Test conducted for 48 hrs under the static system. <=24 hours old water flea used as a test organism. The lethal concentration (LC50) value of test chemical in aquatic invertebrate (Daphnia magna) on mortality effect is found to be 0.17 mg/L.Thus considering the CLP Criteria for aquatic classification of the substance ,it can be assumed that test chemical could exhibit toxicity to aquatic invertebrate (Daphnia magna) in the aquatic acute 1 classification category.

Long term toxicity to aquatic invertebrates:

1. After the exposure of test chemical with daphnia magna for 21 days effect were not observed at the concentration 14 mg/l. Thus NOEC was determine to be 14 mg/l. By considering this NOEC value it is concluded that test chemical is nontoxic to aquatic invertebrates and cannot be classified as per the CLP regulation.  

2. After the exposure of test chemical with daphnia magna for 21 days no effects were observed on reproduction rate and appearance of 1st offspring at the concentration 91 mg/l.

Thus based on the overall studies, it was concluded that the test chemical was nontoxic to aquatic invertebrate and it cannot be classified as per the CLP classification criteria.

 

 

Toxicity to algae and cyanobacteria:

Toxicity study was conducted to evaluate the effect of test chemical on the cell proliferation of freshwater green algae Scenedesmus quadricauda. Test chemical exposed for 8 days with the green algae. Test performed under the static system by using 10 days old culture. Test substance was dissolved in bi-distilled water, the stock solution neutralized. Two parallel concentration were used in the series which by gradual dilution (factor: 0.5). Control were also used in the study. Algae from permanent cultivation were obtain. New breeding of stock cultures in the 10-day cycle added. Inoculation of the test cultures from 10 days old precultures and same culture conditions for parent, preliminary and test organism were maintain throughout the study. From each inoculated batch, three 10 ml culture tubes were used and one tube per control. Shake the test cultures once a day. Cell density determination at the end of the test photometric at 578 nm. Very low effect were observed on the growth and cell proliferations of green algae after the exposure of test chemical for 8 hrs. Based on the effect observed on the cell proliferation rate of green algae Scenedesmus quadricauda after 8 days of exposure, the LOEC was observed at 2370 mg/l. based on the LOEC, chemical consider to be nontoxic and not classified as per the CLP classification criteria.

Study was conducted to determine the effect of test chemical on the growth and cell proliferation of microorganisms Entosiphon sulcatum. Test conducted under the static system at 25° C. After the exposure of test chemical for 72 hrs, with microorganisms Entosiphon sulcatum, the LOEC was observed at 40 mg/l.

Additional information

Summarized result for the toxicity of test chemical on the growth and mortality of aquatic life’s including fish, invertebrates, algae and microorganism were studied and are as mention below:

 

Short term toxicity to fish:

Based on the various experimental data for the test chemical studies have been reviewed to determine the toxic nature of test chemical on the mortality of fishes. The studies are as mentioned below:

 

The first key study was designed to assess the acute toxic effects of the test compound on the Zebra fish (Danio rerio). Bowl aquaria containing 10 liters of deionized water were loaded with 8 fishes each. A static procedure was used for the study and it was conducted in compliance with the OECD Guideline 203 (Fish, Acute Toxicity Test). The test solution was prepared by dissolving 1g of the test substance in10 liters deionized water with continuous stirring for achieving the test concentration of 100 mg/L, respectively. The limit test at 100 mg/L was conducted and it was observed that the LC-50 is greater than this concentration. 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. 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 found in the control aquaria. The LC0 (96 hours) was observed at 100 mg/L (highest concentration at which no mortality was observed). LC50 (96 hours) was > 100mg/L.

 

First study was supported by the second experimental study. The study was designed to assess the acute toxic effects of the test compound on the Zebra fish (Danio rerio). Bowl aquaria containing 10 liters of deionized water were loaded with 8 fishes each. A static procedure was used for the study and it was conducted in compliance with the OECD Guideline 203 (Fish, Acute Toxicity Test). The test solution was prepared by dissolving 1g of the test substance in10 liters deionized water with continuous stirring for achieving the test concentration of 100 mg/L, respectively. The limit test at 100 mg/L was conducted and it was observed that the LC-50 is greater than this concentration. 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. Since no mortalities and no adverse symptoms were observed after 96 hours, the test was continued for a period of seven days to know the No Observed Effect Concentration (NOEC). The test vessels used were all glass bowl aquaria of 12” each. In a 96 h study for test chemical onDanio 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 found in the control aquaria. Based on nominal concentration, no mortalities were observed at 100 mg/l after 96 hrs of exposure. Hence, the experiment was continued up to seven days and the no observed effect concentration (NOEC) for test chemical on Danio rerio was determine to be 100 mg/L. Based on the no effect chemical consider to be nontoxic to fish growth.

 

Similar study was conducted to determine the effect of test chemical on the growth and mortality of Oncorhynchus mykiss (previous name: Salmo gairdneri). Based on the mortality of fish observed, caused by the test chemical after the exposure of 96 hrs, the LC50 value was determine at 2800 mg/l. Based on the LC50 value, chemical consider to be nontoxic and not classified as per the CLP classification criteria.

 

In the fourth supporting study toxicity was measured. Aim of this study was to determine the effect of test chemical on the growth and mortality of Oncorhynchus mykiss (previous name: Salmo gairdneri). Test conducted under the static system for 96 hrs. Test protocol and fishes holding was performed according to the Ontario Ministry of the Environment guidelines. Before the addition of fish to the test solutions, all of the test pails were sampled to measure pH, electrical conductivity, dissolved oxygen, temperature. Ten trout were added to each pail. Fishes maintained at 6°C until needed. The fish were fed a maintenance ration of a commercial pelleted trout food (Martin Feed Mills Limited, Ontario). The water supply for the continuous flow-through holding tanks was obtain from Winnipeg River and purified by sand filtration and ultraviolet light sterilization, and distributed through polyvinylchloride pipes. Randomly selected fish were acclimated at 15°C (-2°C) for a period of >/5 days prior to testing. Feeding was suspended 24-h prior to and during the test period. The 96-h static tests were aerated and conducted at 15°C (±2°C) in a temperature- and photoperiod- (16-h light, 8-h dark) controlled facility. The lethal concentration (LC50) value of sodium iodide in fish [Oncorhynchus mykiss] in a 96 hr study on mortality effect is found to be 3780 mg/L. Based on the LC50, chemical consider to be nontoxic and not classified as per the CLP classification criteria.

 

This study was designed to assess the acute toxic effects of the test compound on the Rainbow trout. Test conducted under the static system for 96 hrs of exposure period. The lethal concentration (LC50) value of test chemical on fish [Oncorhynchus mykiss (Rainbow Trout)] in a 96 hr study on mortality effect is observed to be at 4500 mg/L and 5480 mg/l. Thus, considering the 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 (Rainbow Trout)] and thus not classified as per the CLP classification criteria.     

Based on the data from various experimental reports and peer reviewed journals, it can be concluded that the substance is considered to be not toxic to aquatic environment (fishes) and cannot be classified as toxic as per the criteria mentioned in CLP regulation.

 

Long term toxicity to fish:

Based on the prediction done using ECOSAR version, the long term toxicity on fish was predicted for test substance. On the basis of no effects observed in a freshwater system, 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 the growth of fish at environmentally relevant concentrations and can be considered to be not-classified as per the CLP classification criteria. 

 

Short term toxicity to aquatic invertebrates:

Various short term studies available for the test chemical were reviewed to determine the toxic nature of test chemical on the growth and mobility of aquatic invertebrates. The studies are as mentioned below:

 

The first key study was for the determination of the effect of test chemical on the mortality of daphnia magna. Test conducted for 48 hrs under the static system. <=24 hours old water flea used as a test organism. The lethal concentration (LC50) value of test chemical in aquatic invertebrate (Daphnia magna) on mortality effect is found to be 0.17 mg/L.Thus considering the CLP Criteria for aquatic classification of the substance ,it can be assumed that test chemical could exhibit toxicity to aquatic invertebrate (Daphnia magna) in the aquatic acute 1 classification category.

 

First study was supported by the second study from peer reviewed journal. Aim of this study was to determine the effect of test chemical on the mortality of daphnia magna. Test conducted for 48 hrs under the static system. <=24 h old daphnia were used for the toxicity measurement. Test performed under the static system. The lethal concentration (LC50) value of test chemical in aquatic invertebrate (Daphnia magna) on mortality effect was observed to be 0.23 mg/L. Thus considering the CLP Criteria for aquatic classification of the substance, it can be assumed that test chemical could exhibit toxicity to aquatic invertebrates and classified in the aquatic acute 1 classification category.

 

Similar short term toxicity of test chemical was studied on the growth of freshwater water flea daphnia magna. Test conducted under the static system for 48 hrs. <=24 hrs old daphnia magna were used as a test organism. Based on the mortality of daphnia magna by the chemical exposure for 48 hrs, the LC50 value was determine to be at 0.43 mg/l and 0.78 mg/l also with the slight changes occurs in the temperature, pH and hardness of water. Thus considering the CLP Criteria for aquatic classification of the substance, it can be consider that the test chemical could exhibit toxicity to aquatic invertebrate (Daphnia magna) and classified in the aquatic acute 1 classification category.

 

Similarly aim of this study was to determine the effect of test chemical on the mobility and Floatability of test daphnia magna by providing the exposure period of 24 hrs. Test conducted under the static system. 24 h old daphnia magna were used in the study. After the exposure of test chemical with daphnia magna for 24 hrs, no effect were observed on the mobility and floating behavior at 1 mg/l. Effects i.e EC50 was observed at the concentration 13 mg/l. Thus based on the EC50 value, it can be concluded that the chemical is toxic and can be consider to be classified as aquatic chronic 3 category as per the CLP classification criteria.

 

Thus based on the all above studies, chemical consider to be toxic to the aquatic invertebrates and classified in aquatic acute category 1 as per the CLP classification criteria.

 

Long term toxicity to aquatic invertebrates:

Various long term studies available for the test chemical and structually and functionally similar read acorr chemical were reviewed to determine the toxic nature of test chemical on the growth and mobility of aquatic invertebrates. The studies are as mentioned below

In the first study (from peer reviewed journal) toxicity was measured. Aim of this study is to determine the effect of test chemical on the 24 hrs old Daphnia Magna by providing the exposure period of 21 days. Effect were measured on the basis of reproduction rate inhibition. Test conducted in Equivalent to OECD 211. This experiment was performed on 24 hrs old Daphnia magna (IRCHA strain) and synthetic fresh water was used as medium in this medium The amount of calcium and magnesium ions was 2.5mmol/L. Before preparing the dilution series the test chemical was fully dissolved in water using magnetic stirrers. From the stock solution of the substance to be tested, graduated dilutions with dilution water were produced in the concentration range in which effects were to be expected in accordance with the results from the acute 24 h Daphnia test. Four parallel test vessels per concentration level and the controls comprising at least four vessels were filled with 24 h-old Daphnia 1 animal/50 ml and this meant 20 test animals (1 litre) per concentration level and COD of 15-20 mg/L. The semi-static procedure was used in this experiment the parent animals in the test and control vessels had to be pipetted 3 times a week into freshly prepared test and control media in each case at the corresponding concentration level. Then, the pH value and the oxygen concentration were measured in two test vessels per concentration level and the photo period 9 hrs light and 16 hrs dark. The validity criteria were reproduction rate per parent animal after 21 days, in the case of the test preparation in the beakers, was 88.8 offspring (SD = 13.1; coefficient of variation = 14.8%), The "parent animal mortality" after 21 days was 7.1% in the case of the test preparation in beakers and 9.1% in bottles, the pH always remained in the neutral to subalkaline range. After the exposure of test chemical with daphnia magna for 21 days effect were not observed at the concentration 14 mg/l. Thus NOEC was determine to be 14 mg/l. By considering this NOEC value it is concluded that test chemical is nontoxic to aquatic invertebrates and cannot be classified as per the CLP regulation. 

Similarly the first study was supported by the second study from peer reviewed journal. Aim of this study was to determine the effect of test chemical on the 24 hrs old Daphnia Magna by providing the exposure period of 21 days. Effect were measured on the basis of reproduction rate inhibition and appearance of 1st offspring. Test conducted in Equivalent to OECD 211. This experiment was performed on 24 hrs old Daphnia magna (IRCHA strain) and synthetic fresh water was used as medium in this medium The amount of calcium and magnesium ions was 2.5mmol/L. Before preparing the dilution series the test chemical was fully dissolved in water using magnetic stirrers. From the stock solution of the substance to be tested, graduated dilutions with dilution water were produced in the concentration range in which effects were to be expected in accordance with the results from the acute 24 h Daphnia test. Four parallel test vessels per concentration level and the controls comprising at least four vessels were filled with 24 h-old Daphnia 1 animal/50 ml and this meant 20 test animals (1 litre) per concentration level and COD of 15-20 mg/L. The semi-static procedure was used in this experiment the parent animals in the test and control vessels had to be pipetted 3 times a week into freshly prepared test and control media in each case at the corresponding concentration level. Then, the pH value and the oxygen concentration were measured in two test vessels per concentration level and the photo period 9 hrs light and 16 hrs dark. The validity criteria were reproduction rate per parent animal after 21 days, in the case of the test preparation in the beakers, was 88.8 offspring (SD = 13.1; coefficient of variation = 14.8%), The "parent animal mortality" after 21 days was 7.1% in the case of the test preparation in beakers and 9.1% in bottles, the pH always remained in the neutral to subalkaline range. After the exposure of test chemical with daphnia magna for 21 days no effects were observed on reproduction rate and appearance of 1st offspring at the concentration 91 mg/l. By considering this NOEC value it is concluded that test chemical is nontoxic to aquatic invertebrates and cannot be classified as per the CLP regulation. 

Thus based on the overall studies, it was concluded that the test chemical was nontoxic to aquatic invertebrate and it cannot be classified as per the CLP classification criteria.

 

 

Toxicity to algae and cyanobacteria:

Various short term studies available for the test chemical were reviewed to determine the toxic nature of test chemical on the growth of aquatic algae and cyanobacteria. The studies are as mentioned below:

 

Toxicity study was conducted to evaluate the effect of test chemical on the cell proliferation of freshwater green algae Scenedesmus quadricauda. Test chemical exposed for 8 days with the green algae. Test performed under the static system by using 10 days old culture. Test substance was dissolved in bi-distilled water, the stock solution neutralized. Two parallel concentration were used in the series which by gradual dilution (factor: 0.5). Control were also used in the study. Algae from permanent cultivation were obtain. New breeding of stock cultures in the 10-day cycle added. Inoculation of the test cultures from 10 days old precultures and same culture conditions for parent, preliminary and test organism were maintain throughout the study. From each inoculated batch, three 10 ml culture tubes were used and one tube per control. Shake the test cultures once a day. Cell density determination at the end of the test photometric at 578 nm. Very low effect were observed on the growth and cell proliferations of green algae after the exposure of test chemical for 8 hrs. Based on the effect observed on the cell proliferation rate of green algae Scenedesmus quadricauda after 8 days of exposure, the LOEC was observed at 2370 mg/l. based on the LOEC, chemical consider to be nontoxic and not classified as per the CLP classification criteria.

 

First key study was supported by the second study from secondary source. Study was designed to evaluate the effect of test chemical on the growth of algae. The lowest observed effect concentration (LOEC) value was observed at 2370 mg/L in Scenedesmus quadricauda (Green Algae) in a aquatic toxicity study conducted with test chemical on the basis of Population growth rate. Thus chemical consider to be not classified as per the CLP classification criteria.

 

Similar study was conducted to determine the effect of test chemical on the growth of algae. Test conducted under the static system. The low observed effect concentration (LOEC) value observed is 66 mg/l in Microcystis aeruginosa (Blue-Green Algae) in a aquatic toxicity study conducted with test chemical on the basis of Population growth rate. As low effect were observed on the growth of algae, EC50 was not obtain. Thus on that basis, chemical not consider to be classified as toxic.

 

Based on the overall data from secondary sources and, it can be concluded that the substance is considered to be not toxic to aquatic environment (algae and cyanobacteria) and cannot be classified as toxic as per the criteria mentioned in CLP regulation.

 

Toxicity to microorganisms:

Various studies available for the test chemical were reviewed to determine the toxic nature of test chemical on the growth and other activity of microorganisms. The studies are as mentioned below:

 

In the first study toxicity was measured on the basis of cell growth inhibition. Study was conducted to determine the effect of test chemical on the growth and cell proliferation of microorganisms Entosiphon sulcatum. Test conducted under the static system at 25° C. After the exposure of test chemical for 72 hrs, with microorganisms Entosiphon sulcatum, the LOEC was observed at 40 mg/l.

 

Similarly first study was supported by the second study from secondary source. Study was conducted to evaluate the effect of test chemical on the growth of microorganism Pseudomonas putida. Test conducted for 16 hrs. The low observed effect concentration (LOEC) value observed is 614 mg/l in Pseudomonas putida in a aquatic toxicity study conducted with test chemical on the basis of Cell Proliferation effect. On the basis of LOEC value it is concluded that the test chemical does not exhibit toxicity to microorganism (Pseudomonas putida).

 

Thus based on the above both studies chemical toxicity was observed as very low and the LOEC ranges from 40-614 mg/l.

Based on the toxicity observed on the growth of fish, algae and cyanobacteria, chemical can be consider to be nontoxic and not classified, but as the toxicity observed on the mortality and mobility of daphnia magna after the exposure of chemical for 48 hrs, chemical concluded to be toxic and classified in aquatic acute 1 category as per the CLP classification criteria.