Tridecan-1-ol

Endpoint summary

Description of key information

Short term toxicity to fish

Aim of this study was to determine the nature and effect of test chemical when comes in contact withOryzias latipes. Test conducted according to the OECD Guideline 203 (Fish, Acute Toxicity Test).Test performed under the semi-static condition for the total incubation period of 96 hrs. 0.1 mL/L vehicle was used for the preparation of test solution. 5 L test solution were used in the study. Total amount of the test solution was renewed every 24 hours. Oryzias latipes (Japanese rice fish) is a freshwater fish. 10 fishes per concentration were tested with the tested solution as well as with control.Based on the mortality of fish Oryzias latipes, because of the contact with chemical , test chemical lethal concentration (LC50) was determine to be 1.7 mg/l after the exposure period of 96 hrs.

Long term toxicity to fish

Based on the prediction done using ECOSAR version 1.11, the long term toxicity on fish was predicted for test chemical. On the basis of effects observed in a flow through freshwater system on test organism, the NOEC value for the substance was estimated to be 0.027 mg/l for fish for 28 days of exposure duration. Thus, test chemical can be considered as toxic to fish at environmentally relevant concentrations and hence, considered to be classified in aquatic chronic category 2 as per the CLP classification criteria.

Short term toxicity to aquatic invertebrates

Study was assess to evaluate the nature of test chemical chemical on the growth of aquatic invertebrates daphnia magna for the exposure of 96 hrs. Study was conducted according to the OECD Guideline 202 (Daphnia sp., Acute Immobilisation Test and Reproduction Test).

Test performed under the semi-static condition for the total incubation period of 48 hrs. 100 mL/L vehicle were used for the preparation of 100 ml of test solution. Total amount of test solution was renewed after 24-hour exposure. Chemical tested at various concentrations 0, 0.10, 0.22, 0.46, 1.0, 2.2 mg/L (nominal concentrations) and also on vehicle (100 microl/l). 5 daphnia magna per vessel added and the test repeated 4 times. Room light, 16 hours light / 8 hours dark provided to the test organism.

 

After the exposure of test chemical for 48 hrs effect were observed on the daphnia magna. After 24 hrs, the EC50 was 0.92 mg/l and after 48 hrs the NOEC was determine 0.22 mg/l. The EC50 was determine to be 0.61 mg/l with the 95 % CL of 0.49 - 0.75 mg/L. Based on the EC50, chemical was consider as toxic and classified as aquatic acute 1 as per the CLP classification criteria.

Long term toxicity to aquatic invertebrates

Long term toxicity to aquatic invertebrate study was carried out for assessing the effect of test chemical. The study was performed in accordance with the OECD Guideline 211 (Daphnia magna Reproduction Test) under semi-static conditions. Test chemical solution was prepared in vehicle Dimethylformamide, Hydrogenated castor oil (HCO-40)  (100 microL/L). Test chemical concentrations were verified analytically using GC/MS. Test chemical concentrations used for the study were 0 (control), 0 (vehicle control), 0.022, 0.046, 0.10, 0.22, 0.46 mg/L (geometric ratio: 2.2), respectively. 10 daphnids/conc. (1 per vessel) were exposed to test chemical in test vessel for 21 days. Volume of test solution in test vessel was 80 ml. Total amount of the test solution was renewed every 24 hours. Controls were also run simultaneously during the study. Test conditions involve a temperature of 20 ± 1° C and under a photoperiod of 16 hours light / 8 hours dark.  All experiments were performed in 10 replicates. After an exposure period of 21 days, the reproduction effect of the test organism was noted. On the basis of the effect of test chemical on reproduction rate of the test daphnids, the 21 d NOEC, EC50 and LC50 value was determined to be 0.22, 0.46 and >0.46 mg/l, respectively. Based on the result, test chemical was considered as toxic to aquatic invertebrates at environmental relevant concentrations and hence, considered to be classified in aquatic chronic category 3 as per the CLP classification criteria.

Toxicity to aquatic algae and cyanobacteria

Study was assess to evaluate the nature and effect of test chemical on the growth of green algae for the exposure period of 72 hrs. Study was conducted under the static system. After the exposure effect was determine. Based on the growth rate inhibition of green algae due to the exposure of test chemical , the EC50 and NOEC was 0.012 mg/l and 0.0029 mg/l. But on the basis of Biomass and area under the growth curve, the EC50 and NOEC was determine to be 0.09 mg/l and 0.017 mg/l. Based on the EC50, test chemical was concluded as toxic and can be consider to be classified as aquatic acute 1 as per the CLP classification criteria.

Toxicity to microorganisms

Aim of this study was to determine the toxic nature of test chemical on the growth of microorganism Tetrahymena pyriformis for the total exposure period of 48 hrs. Chemical purchased from Aldrich Chemical Co., Milwaukee, Wisconsin having 95 % purity. Test performed in 3 replicates and each replicate was a five-step graded concentration series using freshly prepared stock solutions. Only replicate with control cultures in the late log-growth-phase (absorbance of 0.6 to 0.9) were used in these studies. Based on the growth rate inhibition of test organisms Tetrahymena pyriformis due to the exposure of test chemical for 48 hrs, the IGC50 was determine to be 586 mg/l.

Additional information

Short term toxicity to fish

Based on the various experimental and predicted data for the target chemical and experimental data for structurally and functionally similar read across chemicals study have been reviewed to determine the toxic nature of target chemical 1-Tridecanol (112-70-9) on the fishes. The studies are as mentioned below:

Aim of this study was to determine the nature and effect of test chemical when comes in contact withOryzias latipes. Test conducted according to the OECD Guideline 203 (Fish, Acute Toxicity Test).Test performed under the semi-static condition for the total incubation period of 96 hrs. 0.1 mL/L vehicle was used for the preparation of test solution. 5 L test solution were used in the study. Total amount of the test solution was renewed every 24 hours. Oryzias latipes (Japanese rice fish) is a freshwater fish. 10 fishes per concentration were tested with the tested solution as well as with control.Based on the mortality of fish Oryzias latipes, because of the contact with chemical , test chemical lethal concentration (LC50) was determine to be 1.7 mg/l after the exposure period of 96 hrs. Based on the LC50, chemical was consider as toxic and classified as aquatic chronic 2 as per the CLP classification criteria.

 

First experimental study was supported by the second supporting study from peer reviewed journal.

Aim of this study was to determine the nature and effect of test chemical when comes in contact withpimephales promelas (Fathead minnow). Chemical was less soluble thus first extracted into hexane or hexane/ether (75: 25) and analyzed on an appropriate GC column utilizing either flame ionization or electron capture detectors. Chemicals were added to water in 500-mL flasks and gently shaken in a 25 ±1°C water bath until the concentration was constant. Samples of saturated water were centrifuged for 30 min.30 days old 0.2 g Pimephales promelas (Fathead Minnow) collected from Environmental Research Laboratory-Duluth. Fish were not fed during the test. Fish were randomly divided amongst the test tanks (control and five different concentrations each in duplicate for proportional diluter system and singly for continuous-flow minidilutor systems).Deaths were recorded after 1, 3, 6, 12, 24, 48,72, and 96 h. As the chemical was not highly soluble thus tested at 0.33 mg/l. After the exposure of chemical 1-Tridecanol on the Pimephales promelas (Fathead Minnow) for 96 hrs, no mortality were observed LC0 was 0.33 mg/l and LC50 was > 0.33 mg/l, respectively.

 

Similarly in the third study for the target chemical f supports the classification of chemical. In a 96 hours short team toxicity study, the effect of test material was evaluated on Fathead Minnows (Pimephales promelas). Test conducted on 30 days old fish. The results show no mortality in treated fish. Therefore, NOEC was considered to be 0.64 mg/L when Fathead Minnows (Pimephales promelas) treated with test material for 96 hours. The results show 0% Lethality i.e 100% survival for test organism’s at given concentration.

The 96 hr NOEC value was determined to be 0.64 mg/l.

 

The fourth study consider for the test chemical . Aim of this study was to determine the nature and effect of test chemical when comes in contact with testfish. Test conducted according to the OECD Guideline 203 (Fish, Acute Toxicity Test). Test performed under the static condition for the total incubation period of 96 hrs. Based on the mortality of fish, because of the contact with test chemical , lethal concentration (LC50) was determine to be 2.8 mg/l after the exposure period of 96 hrs. Based on the LC50, chemical was consider as toxic and classified as aquatic chronic 2 as per the CLP classification criteria.

In a supporting study, short term toxicity to fish study was carried out for assessing the effect of test chemical. The study was performed following the U. S. EPA test method. Pimephales promelas (Fathead minnow) (of 1, 4 and 7 day larvae) was used as a test organism. Test organism waas obtained from Fathead minnow culture unit at the EPA Newtown Facility. Larvae were fed 3 drops per replicate of concentrated brine shrimp slurry. The larvae were fed once on the first day, twice daily on days 1 to 6 and not fed on the last day. Test chemical concentrations used for the study were 0, 0.75, 1.5, 3.0, 6.0 and 11.9 mg/l, respectively. Test concentrations were verified analytically. 3 grab samples were taken of the final test solution and the measured concentration of the high concentration (11.9 mg/l) was 1.3 mg/l. Grab samples of final concentrations of 6.0 and 3.0 mg/l gave measured concentrations of 0.09 mg/l and none detected. Test fishes (10 test organism/replicate) were exposed to different test chemical concentrations in 600 ml borosilicate glass beakers. Dilution water was prepared with reagant grade chemicals added to a carbon-filtered, deionised Cincinnati tap water that was treated in a Millipore Milli-Q system. It was aerated vigorously for approx. 24 hours before usage. Test conditions include a temperature of 25 +/- 1°C, pH of 7.5 (7.24-7.81), hardness of 86 - 94 mg/l, alkalinity of 56 - 64 mg/l and dissolved oxygen of 6.0 mg/l (4.4-7.2 mg/l), respectively. Control was also run simultaneously during the study. All experiments were performed in 4 replicates. After an exposure period of 7 days, survival and growth of the test organism was noted. Based on the effect on survival/mortality of the test fishes, the 7 day NOEC and LOEC value was determined to be > 1.5 to < 11.9 mg/l and > 3 to < 11.9 mg/l, respectively. On the basis of the effect on growth, the 7 day NOEC and LOEC value was determined to be > 0.75 to < 3 mg/l and > 1.5 to < 6.0 mg/l, respectively.

 

Based on the experimental data as well as predicted data for the target chemical,it can be concluded that the substance is considered to be toxic to aquatic environment (fishes) and can be classified as aquatic chronic 2 as per the criteria mentioned in CLP regulation.  

Long term toxicity to fish

Based on the prediction done using ECOSAR version 1.11, the long term toxicity on fish was predicted for test chemical. On the basis of effects observed in a flow through freshwater system on test organism, the NOEC value for the substance was estimated to be 0.027 mg/l for fish for 28 days of exposure duration. Thus, test chemical can be considered as toxic to fish at environmentally relevant concentrations and hence, considered to be classified in aquatic chronic category 2 as per the CLP classification criteria.

Short term toxicity to aquatic invertebrates

Based on the various experimental for the target chemical study have been reviewed to determine the toxic nature of test chemical on the mobility and growth of aquatic invertebrates. The studies are as mentioned below:

 

In the first key study for the test chemical from authoritative database , determine the toxicity. Study was assess to evaluate the nature of test chemical chemical on the growth of aquatic invertebrates daphnia magna for the exposure of 96 hrs. Study was conducted according to the OECD Guideline 202 (Daphnia sp., Acute Immobilisation Test and Reproduction Test).Test performed under the semi-static condition for the total incubation period of 48 hrs. 100 mL/L vehicle were used for the preparation of 100 ml of test solution. Total amount of test solution was renewed after 24-hour exposure. Chemical tested at various concentrations 0, 0.10, 0.22, 0.46, 1.0, 2.2 mg/L (nominal concentrations) and also on vehicle (100 microl/l). 5 daphnia magna per vessel added and the test repeated 4 times. Room light, 16 hours light / 8 hours dark provided to the test organism.

 

After the exposure of test chemical for 48 hrs effect were observed on the daphnia magna. After 24 hrs, the EC50 was 0.92 mg/l and after 48 hrs the NOEC was determine 0.22 mg/l. The EC50 was determine to be 0.61 mg/l with the 95 % CL of 0.49 - 0.75 mg/L. Based on the EC50, chemical was consider as toxic and classified as aquatic acute 1 and chronic 1 as per the CLP classification criteria.

 

First experimental study was supported by the second supporting study from peer reviewed journal . Study was access to evaluate the toxic nature of test chemical on the growth of daphnia magna for 48 hrs of exposure. Study was conducted according to the OECD guideline 202 (Daphnia sp., Acute Immobilisation Test and Reproduction Test). After the exposure effect were observed. The effect concentration (EC50) was determine to be 0.5 mg/l by the test chemical . Based on the EC50 chemical was consider as toxic and can be consider to be classified as aquatic acute category 1 as per the CLP classification criteria.

 

 

Similarly in the third supporting study for the target chemical from peer reviewed journal . In a 48 hours short team toxicity study, the effect of test material was evaluated on Mysidopsis bahia (mysids). The test substance was introduced by feed in a concentration of 600 mg/L. The reactor was seeded with activated sludge from an industrial wastewater treatment plant treating ethoxylated surfactant. The reactors were operated for 10 weeks except reactor 4 of which operation was terminated after 8 weeks. The results show mortality at 2.2 mg/L. Therefore, LC50 for test material was considered to be 2.2 mg/L when tested on Mysidopsis bahia(mysids). Estimates by probit method and reported as concentration (for untreated product) or a dilettante (for effluents) resulting in death of 50 % of test organisms (LC50). LC50 for test material was determine to be 2.2 mg/l when tested on Mysidopsis bahia (mysids)  for 48 hours. Based on LC50 chemical was consider as toxic and classified as aquatic acute category 2, as per the CLP classification criteria

 

The data from the secondry data source for the target chemical concluded that the chemical was toxic to invertebrates.

Study was assess to evaluate the nature of test chemical on the growth of aquatic invertebrates daphnia magna for the exposure of 96 hrs. As the chemical was treated with the test organism daphnia magna effect were observed (EC50) was determine at 0.51 mg/l. Based on the EC50, chemical was consider as toxic and classified as aquatic acute 1 as per the CLP classification criteria.

Another short term toxicity to aquatic invertebrate study was carried out for assessing the effect of test chemical. The study was performed following the principles of the OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test). The test substance was water-insoluble, however, a fine-turbid suspension could be prepared using slightly prewarmed demineralised water (23 C to 25°C). The test substance and prewarmed water were placed into vessels and were shaken manually for 3 minutes. The resulting suspension remained stable even at temperatures of 20°C and could be diluted. The suspensions were not filtered. Note, effects seen at concentration less than SPARC estimated water solubility. The tests reported in this entry used a standard methodology. An additional test was also carried out using a non-standard submergible chamber procedure. Daphnia magna of 6 to 24 hr old (Water flea) obtained from Institut fur Wasser-, Boden-, und Lufthygiene was used as a test organism. Test daphnids (5 test organisms) were exposed to different test chemical concentrations (i.e., 0.178, 0.316, 0.562, 1.00, 1.78 and 3.16 mg/l, respectively) in glass vessels (diameter: 38 mm, height: 60 mm, volume: 50 ml) for a period of 48 hrs. Test conditions involve a temperature of 20°C, hardness of 250 mg CaCO3/l, pH of 7.9 (mean), dissolved oxygen of >80% of maximum saturation and alkalinity of 0.8 mM/l under a photoperiod of 16 hours light/8 hours darkness, white type fluorescent light, respectively. Control was also run simutaneously during the study. All test experiments were performed in 4 replicates. After an exposure period of 48 hrs, the mobility of the test organism was noted. On the basis of effect of test chemical on mobility of test daphnids, the 48 hr NOEC, EC50 and EC100 value was determined to be 0.316, 0.765 and 1.78 mg/l. Based on the result, test chemical was considered as toxic to aquatic invertebrates at environmental relevant concentrations and hence, considered to be classified in aquatic acute category 1 as per the CLP classification criteria.

 

Based on the experimental data of test chemical ,it can be concluded that the test substance is considered to be toxic and classified in aquatic acute 1 as per the CLP classification criteria.

Long term toxicity to aquatic invertebrates

Experimental studies of the test chemical and various supporting weight of evidence studies for its structurally similar read across chemical were reviewed for long term toxicity to aquatic invertebrate end point which are summarized as below:

 

In an experimental study from authoritative database, long term toxicity to aquatic invertebrate study was carried out for assessing the effect of test chemical. The study was performed in accordance with the OECD Guideline 211 (Daphnia magna Reproduction Test) under semi-static conditions. Test chemical solution was prepared in vehicle Dimethylformamide, Hydrogenated castor oil (HCO-40)  (100 microL/L). Test chemical concentrations were verified analytically using GC/MS. Test chemical concentrations used for the study were 0 (control), 0 (vehicle control), 0.022, 0.046, 0.10, 0.22, 0.46 mg/L (geometric ratio: 2.2), respectively. 10 daphnids/conc. (1 per vessel) were exposed to test chemical in test vessel for 21 days. Volume of test solution in test vessel was 80 ml. Total amount of the test solution was renewed every 24 hours. Controls were also run simultaneously during the study. Test conditions involve a temperature of 20 ± 1° C and under a photoperiod of 16 hours light / 8 hours dark.  All experiments were performed in 10 replicates. After an exposure period of 21 days, the reproduction effect of the test organism was noted. On the basis of the effect of test chemical on reproduction rate of the test daphnids, the 21 d NOEC, EC50 and LC50 value was determined to be 0.22, 0.46 and >0.46 mg/l, respectively. Based on the result, test chemical was considered as toxic to aquatic invertebrates at environmental relevant concentrations and hence, considered to be classified in aquatic chronic category 3 as per the CLP classification criteria.

 

In a supporting weight of evidence study, chronic toxicity to aquatic invertebrate study was carried out for assessing the effect of test chemical (secondary source, 2006). The study was performed following the principles of the OECD Guideline 211 (Daphnia magna Reproduction Test). Modification with the OECD TG is that aeration of exposure media was done. Test solutions were prepared daily by stirring the test substance in test media under slow stir conditions (21 h) in sterilized mixing vessels. The mixing vessels were cylindrical brown glass bottles with teflon covered screw caps, fitted with a drain port near the bottom for drawing off the test solution. The volume of the mixing vessels was 2 L. After stirring, the contents of the vessels were left to settle for 2 h. The saturated aqueous phase was then taken out of the drain port. The first fraction 0-100 mL was discarded. The fraction between 100 and 1800 mL was used for rinsing (200 mL) and filling (1000 mL) the test flasks for toxicity testing and for analytical measurements (500 mL), if done. Rinsing of the test vessels was carried out to saturate the surfaces of the test vessels. After filling, the vessels were closed immediately by using autoclaved silicone stoppers and only opened to introduce the test organisms and again at the renewals of the test media. The test media were not stored for more than 1 - 2 hours prior to testing. Daphnia magna STRAUS (Water flea) of 4 to 24 hr old was used as a test organism. Test organisms was bred in the laboratory of the Fh-IME (testing facility). The Daphnia magna were fed at each renewal with suspensions of unicellular green algae. The suspensions of Desmodesmus subspicatus (daily prepared from axenic cultures) were controlled analyzed for microbial contamination one and two weeks after test start by using "Cult-Dip combi® Dip Slides (Merck)". No bacterial contamination was detected. The content of food in the test suspensions, measured as turbidity at 758 nm, increased during the test from 7 mg C/L equivalents to 15 mg C/L equivalents. Test chemical concentrations used for the study were 0, 0.025, 0.069, 0.185 and 0.500 mg/l (nominal conc.); < Limit of quantification, 0.02, 0.056, 0.163 and 0.534 mg/l (measured initial conc.) and < Limit of quantification, 0.003, 0.005, 0.014 and 0.095 mg/l (geometric measured conc.), respectively. All the test concentrations were sampled for chemical analysis three times a week at renewal of the test media. A 500 mL aliquot of the fresh solutions was used for analysis. After 24 h, at the next renewal, the aged test liquids were pooled (vessels 1- 5 and 6-10) and analysed. The analyte was extracted from the aqueous test samples by liquid-liquid partitioning with n-hexane. After derivatization of the analyte by MSTFA measurement was performed by GC-MS using n-dodecanol-d25 as internal standard. The method was validated for the determination of the test item in Daphnia test medium in the concentration range of 1.0 - 100 μg/L. Test daphnids (10 organisms) were exposed to test chemical in test vessel for an exposure period of 24 hrs. ll test vessels were aerated with sterile filtrated synthetic air: the autoclaved silicone stoppers were fitted with fine glass capillaries connected to the aeration unit. The aeration was necessary to avoid severe oxygen depletion due to the increase of transferred bacteria with growing Daphnia magna as observed in pre-studies and the associated oxygen consumption by the degradation of the test substance. Test conditions involve a photoperiod of 16/8 hour light: dark condition, temperature of 21 to 22°C, photoperiod of 9.3 to 9.5, the oxygen saturation never fell below 56 % (4.0 mg/L) and light intensity of 585 to 647 lux, respectively. The parent Daphnia magna were assessed visually daily for immobility and any other abnormalities in appearance and behaviour. At study termination, the length of the adults was measured by digital photography and image analysis and their statistics compared with those of the control animals. The newborn Daphnia magna in each beaker were counted at each daily renewal of the test solutions, inspected for abnormalities in condition, and removed. The evaluation of the concentration-effect relationships and the calculations of effect concentrations were based on mean measured initial concentrations as multiple peak concentrations, as well as on geometric means between mean measured initial and aged (24h) test concentrations. For each endpoint, the NOEC, LOEC, and, if possible, the EC50, EC20 and EC10 were determined. A LOEC and NOEC were calculated by ANOVA followed by Williams’ test or an appropriate nonparametric test suggested by the ToxRat program. When the test results showed a concentration-response relationship, the data were analysed by regression using Probit-analysis assuming log-normal distribution of the values using the computer program ToxRat program. Based on the effect on reproduction rate of the test daphnids, the 21 d NOEC, LOEC, EC10 and EC20 value was determined to be 0.014, 0.095, 0.013 and 0.034 mg/l (measured geometric conc.) and 21 d NOEC & LOEC value was determined to be 0.185 and 0.5 mg/l (nominal concentration), respectively. Based on the result (21 d NOEC = 0.185 mg/l), test chemical was considered as toxic to aquatic invertebrates at environmental relevant concentrations and hence, considered to be classified in aquatic chronic category 3 as per the CLP classification criteria.

 

For the test chemical, long term toxicity to aquatic invertebrate study was carried out for 21 days. Study was performed following the principles of the OECD test guideline 202, part 2 (from handbook, 2009 and secondary source, 1995). Test chemical concentrations were measured by DOC analysis. Total 20 daphnids (5 per test vessel) were exposed to different test chemical conc. (i.e., 1, 3, 10, 30, and 100 mg/l) for a period of 21 days under flow through conditions. Test solutions were changed three times per week. The test vessels are controlled regularly and the time of first appearance of decedents and the number of juvenile organisms was determined. Measured (DOC) concentrations were 0.6/0.5 mg/l at 0 hours, 1.3/1.2 mg/l at 48 hours, and 1.9/1.8 mg/l at 120 hours for the 10 mg/l group. Similar measured concentrations were obtained in the 30 mg/l and 100 mg/l groups. No information was given on possible physical effects on the Daphnia (surface floating, etc.). At (nominal) concentrations of 1 mg/l no effects were noted, while at concentrations of 3 mg/l and above, fertility was significantly effected. There were no effects on the adults in any group including controls on day 2. On day 5, 1/(20) died in the control group, and 8/(20) in the 10 mg/l group, 4/(20) in the 30 mg/l group, and 1/(20) in the 100 mg/l group. By day 21, adult mortality reached or exceed 50% in all test groups above 3 mg/l, while being 10% in the control and low dose groups. Thus, on the basis of these effects, the 21 d NOEC and LOEC value was determined to be 1.0 mg/l and 3.0 mg/l, respectively.  Thus, test chemical was considered as toxic to aquatic invertebrates at environmental relevant concentrations and hence, considered to be classified in aquatic chronic category 3 as per the CLP classification criteria.

 

Another chronic toxicity to aquatic invertebrate study (Kuhn R et. al., 1989) was carried out for assessing the effect of test chemical. The study was performed in accordance with the OECD Guideline 211 (Daphnia magna Reproduction Test) and Federal Environment Agency (1984), respectively. The test substance was dispersed to make up a stock solution of 200 mg/L, then gradual serial dilutions (corresponding to a ratio of 1:2) of the stock solution were made to produce the concentration range tested. Samples were taken twice from selected concentration levels of the test series during the test period and analysed chemically. The first sampling was taken before the 7th day previous to any offspring appearance, the second sample was taken between day 16 and day 21. No further details on analytical methods were presented. Test organism Daphnia magna (Water flea) was maintained in accordance with the procedure practised since 1978. During the acclimation period, test organism was fed daily with dry algae Scenedsmus spp. 9g of feed were suspended in 1000 mL tap water and 2 mL were added to each 2 L cultures. Test daphnids (5 test organisms/vessel) were exposed to test chemical conc. (0.4 to 50 mg/l) in 400 ml glass beakers filled with 250 mL test water.  Deionised water was used to prepare standard artificial medium (synthetic fresh water) as stated by DIN - German Institute of Standardisation. Aeration was not provided in the test vessel. All experiments were performed in 4 repilcates. Test conditions involve a temperature of 25 +/- 1°C, pH of > 7, dissolved oxygen >69%, light with fluorescent lamps - Philis TL having intensity of 40/25W. Mortality, reproduction rate and appearance of offspring, daily. Student's t-test and U-test was used for deterimining the NOEC of reproduction rate and parent mortality. On the basis of the effect on reproduction rate of the test organism, the 21 day NOEC value was determined to be 1.0 mg/l.

 

On the basis of the above results, it can be concluded that the test chemical test chemical was considered as toxic to aquatic invertebrates at environmental relevant concentrations and hence, considered to be classified in aquatic chronic category 3 as per the CLP classification criteria.

Toxicity to aquatic algae and cyanobacteria

Based on the various experimental data for the target chemical study have been reviewed to determine the toxic nature on the growth of aquatic algae and cyanobacteria. The studies are as mentioned below:

 

In the first key study for the target chemical was described in authorative database,

Study was assess to evaluate the nature and effect of test chemical on the growth of green algae for the exposure period of 72 hrs. Study was conducted under the static system. After the exposure effect was determine. Based on the growth rate inhibition of green algae due to the exposure of test chemical , the EC50 and NOEC was 0.012 mg/l and 0.0029 mg/l. But on the basis of Biomass and area under the growth curve, the EC50 and NOEC was determine to be 0.09 mg/l and 0.017 mg/l. Based on the EC50, test chemical was concluded as toxic and can be consider to be classified as aquatic acute 1 as per the CLP classification criteria.

 

Similarly in the second supporting study for the target chemical from secondry source says that the chemical was toxic. Study was assess to evaluate the nature and effect of test chemical on the growth of algae for the exposure period of 72 hrs. After the exposure of chemical for 72 hrs, the EC50 was determine to be 0.1-1 mg/l. Based on the EC50, test chemical was concluded as toxic and can be consider to be classified as aquatic acute 1 as per the CLP classification criteria.

 

The fourth study consider for the test chemical from authorative database. Study was assess to evaluate the nature and effect of test chemical on the growth of green algae for the exposure period of 72 hrs. Study was conducted under the static system. After the exposure effect was determine. Based on the growth rate inhibition of green algae due to the exposure of test chemical , the EC50 and NOEC was 0.56 mg/l and 0.028 mg/l. But on the basis of Biomass and area under the growth curve, the EC50 and NOEC was determine to be 0.72 mg/l and 0.09 mg/l. Based on the EC50, test chemical was concluded as toxic and can be consider to be classified as aquatic acute 1 as per the CLP classification criteria.

 

Based on the experimental data for the test chemical it can be concluded that the substance is considered to be toxic to aquatic algae and cyanobacteria and classified as aquatic acute 1/ chronic 1 category as per the CLP classification criteria.

 

Toxicity to microorganisms

Various experimental data for the target chemical have been reviewed to determine the toxic nature of test substance on the growth of microorganisms. The studies are as mentioned below:

In the first key study for the target chemical from peer reviewed journal , Aim of this study was to determine the toxic nature of test chemical on the growth of microorganism Tetrahymena pyriformis for the total exposure period of 48 hrs. Chemical purchased from Aldrich Chemical Co., Milwaukee, Wisconsin having 95 % purity. Test performed in 3 replicates and each replicate was a five-step graded concentration series using freshly prepared stock solutions. Only replicate with control cultures in the late log-growth-phase (absorbance of 0.6 to 0.9) were used in these studies. Based on the growth rate inhibition of test organisms Tetrahymena pyriformis due to the exposure of test chemical for 48 hrs, the IGC50 was determine to be 586 mg/l.

First experimental study was supported by the second supporting study from peer reviewed journal. In a 48 hours short team toxicity study, the effect of test material was evaluated on 484 Tetrahymena pyriformis Ciliate. The test substance was test on the basis of QSAR in a concentration of 1001.5 mg/L. The results show 50% inhibition in growth rate of test organism’s population at given concentration. Therefore, IC50 for test material was considered to be growth inhibiter at 1001.5 mg/L when tested on Tetrahymena pyriformis Ciliate for 48hrs.

 

Similarly in the third supporting study test chemical from another peer reviewed journal study was conducted. In a 48 hours short team toxicity study, the effect of test material was evaluated on 484 Tetrahymena pyriformis Ciliate. The test substance was test on the basis of QSAR, TOXICITY and BCF MODELS in a concentration of 1.05 mg/L (1050 µg/L). The results show 50% inhibition in growth rate of test organism’s population at given concentration. Therefore, IC50 for test material was considered to be growth inhibitor at 1.05 mg/L (1050 µg/L) when tested on 484 Tetrahymena pyriformis Ciliate for 2 days.

 

The first two study supports the nontoxic nature of chemical but according to the remaining study chemical was toxic and the MIC ranges from 1.05 mg/l to 1001.5 mg/l.