N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)isophthalamide

Endpoint summary

Additional information

Fish, acute

Freshwater fish (Brachydanio rerio) were exposed to the test article for 96 hours at nominal concentrations of 1, 10, 50, 100 and 250 mg of test article per liter of test medium. Ten fish were used per treated group, in comparison with an untreated group. A static system was used, and each group of 10 fish was kept in 4 litres of test medium. No auxiliary substance was used

The following results were obtained from the study for the test item: LC 50 > 250 mg/l, LC0 = 100 mg/l and LC100 > 250 mg/l.

A second study was conducted as a limit test to confirm that the test item has no effects on the test organisms around maximum concentration on applied test guidelines. No effect was observed on test organisms. Therefore, it was judged that the test item had no adverse acute effect on test organisms around maximum concentration on applied test guidelines. The test item concentrations in the test solution was maintained within ±20 % of measured concentration at the preparation and the environmental conditions were within the suitable range, therefore, it was concluded that this study complied with the applied test guidelines.

As a result of the study, both the 48-hour and 96-hour LC50 to Medaka were > 110 mg/L

Daphnia, acute 

A study (CERI, 2010) was conducted according to OECD Guideline 202 in order to confirm the effect of the test item on the test organisms below the solubility of the test item in dilution water. As a result, pH unadjusted 48 -hourEC50 was 15 mg/L.In the highest concentration level, since pH exceeded 9, the test concentration division which performed pH adjusted levels prepared separately. As a result, pH adjusted 48 -hour EC50 was 16 mg/L. From this result, it is guessed that pH is not participating in the toxicity over the Daphnia magna of a test item. The concentration of the test item in the test solution during exposure was maintained at that of the start of the exposure. The environmental conditions were within the suitable range; therefore, it is concluded that this study complied with the applied test guidelines.

 

In a second study Daphnia magna were exposed to the test article for 48 hours at the nominal concentrations of 1, 10, 50, 100 and 250 mg of test article per liter of test medium. Measurements of pH, dissolved oxygen and temperature were performed at the beginning and at the end of the test for each test medium. Each test medium was sampled at the start and at the end of the test.

The following results were obtained from the study for the test item: EC50 (24 h) > 250 mg/l, EC50 (48 h) = 250 mg/l, EC0 < 1 mg/l and EC100 > 250 mg/l.

Daphnia, chronic

A Daphnia magna (Crustacea, Cladocera) reproduction test was performed according to the OECD Guideline No 211 (adopted September 21, 1998) and Principles of Good Laboratory Practice (GLP, OECD 1997).

The aim of the study was the determination of the reproductive output of Daphnia magna exposed to a range of concentrations of the test substance (determination of NOEC after 21-day exposure). 5 concentrations in the range from 1.00 to 100 mg/L with separation factor of 3.2 were used. The NOEC (21-day in mg/I) is 10 mg/I while LOEC is 32 mg/L.

Algae

The study (CERI, 2010) was conducted in order to estimate the effect on the test organisms under the solubility of the test item in medium. As a result, in pH unadjusted test, the EC50 and NOEC of the test item were 27 mg/L and 1.0 mg/L, respectively. The pH of the test solution at the start of exposure in the higher test item concentration tended to be higher (pH was 9.4 in 98 mg/L exposure level which was the highest exposure level at the start of exposure). Therefore the pH of test solution was adjusted to around that of medium, and this study was conducted. As a result, the EC50 and NOEC of the test item were 52 mg/L and 3.2 mg/L, respectively. The effect on the test organism was eased somewhat. Therefore, it was considered that the effect of the test item on the test organism was the total effect of pH and toxicity of the test item and the results from experiments with adjusted pH were used for the assessment (EC50 and NOEC: 52 mg/L and 3.2 mg/L).

In pH unadjusted test, the EC50 and NOEC of the test item were 27 mg/L and 1.0 mg/L, respectively. In pH adjusted test, the EC50 and NOEC of the test item were 52 mg/L and 3.2 mg/L, respectively.

 

In a second study (Pharmakon, 1997), the following results were obtained:

- EC50, for freshwater green algae (actual concentration of test article): Growth curves (IA) EC50 > 250 mg/l, Growth rates (Iµ) > 250 mg/l

- NOEC, for freshwater green algae (actual concentration of test article): Growth curves (IA) NOEC > 250 mg/l, Growth rates (Iµ) > 250 mg/l

Microorganisms

The inhibitory effect of the test item on the respiration rate of aerobic wastewater microorganisms of activated sludge was investigated in a 3-hour respiration inhibition test according to OECO Guideline for Testing of Chemicals, No. 209.The following nominal concentrations were tested: 10, 32, 100, 320, and 1000 mg/l.

Up to and including the concentration of nominal 100 mg/L l the test item had no significant («15%) inhibitory effect on the respiration rate of activated sludge after the incubation period of three hours. At the higher test item concentrations of nominal 320 and 1000 mg/L the inhibitory effect increased to 24% and to 45%, respectively.

The calculated 3-hour EC-values were as follows:

NOEC (EC15): 148 mg/L:

EC20: 220 mg/L

EC50: 1250 mg/L