Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 260-828-5
CAS number: 57583-34-3
RESULTS: RANGE FINDING- Measured substance concentrations: The chemical analysis of the substance (as Sn) in a 100% Water Soluble Solution (WSF) resulted in 170 micrograms Sn/L on t=0 and 180 micrograms Sn/L on t=3 days), respectively. The Sn concentration was thus stable during the range-finding test.- Results: The range-finding test revealed an expected NOEC of approximately 0.01% of the WSF. Based on the results of the range-finding test, it was decided to test 0, 0.003, 0.01, 0.03, 0.3, 10 and 33% WSF. However, as the measured Sn concentration at different levels was not consistent, it was decided to repeat the (main) test and add 99% WSF to the concentration series.RESULTS: EXPOSED- Nominal/measured concentrations: Nominal concentrations were 0, 0.003, 0.01, 0.03, 0.3, 10, 33 and 99% of the WSF. At all nominal concentrations <9.9% WSF, the measured Sn concentrations were less than the analytical level of detection (LOD). The mean recovery of the Sn concentration at the end of the test was 89% and supports the conclusion of the range finding test that the test substance was stable during the test period. The measured Sn concentrations showed a linear relationship with the percentage of the dilutions of the WSF (plotted on a Ln scale), allowing for an extrapolation of Sn concentrations where measured values were <LOD. Therefore, the effect values were calculated on the basis of the geometric mean of the measured and extrapolated Sn concentrations at the start and end of the test. The geometric mean measured concentrations corresponding to the nominal test substance concentrations of 0.003, 0.01, 0.03, 0.3, 10, 33 and 99% WSF were 0.007, 0.023, 0.072, 0.76, 28, 95 and 294 micrograms Sn/L, respectively.Remark: There was a difference in the measured Sn concentration of the WSFs between the range-finding and the final growth inhibition tests. Attempts to obtain consistent Sn concentrations in WSFs prepared at different times with the same method did not succeed. Even the addition of energy with the aid of an Ultra Turrax homogenizer did not yield a higher Sn concentration.Some algal density determinations deviated from the expected range. The reason for this variation is uncertain, but might be due to the tendency of the test organism for a synchronic growth pattern. Nevertheless, no determinations were regarded as outliers, as the averages revealed a normal pattern.- Effect values (micrograms Sn/L and micrograms MMT(2-EHMA)/L respectively, both with 95% confidence limits): micrograms Sn/L micrograms MMT(2-EHMA)/LNOEC 95 595ErC10 130 814ErC50 >294 >1840ErC90 >294 >1840EbC10 4.8 (0.76-28)* 30 (4.8-173)*EbC50 >294 >1840EbC90 >294 >1840* = range between tested concentrationsNOEC = estimated No Observed Effect ConcentrationErC values = Effect Concentration with regard to the growth rateEbC values = Effect Concentration with regard to area under the growth curvesRESULTS CONTROL: Microscopic inspection of the morphology of algal cells in the pre-culture at the start of the test revealed normal cells. At the end of the test, no abnormal cells were observed in the cultures containing different concentrations of the test substance.
The toxicity of MMT(EHMA) to the fresh water green alga Scendesmus
subspicatus was determined in a 72 -h growth inhibition tests following
the OECD testing guideline 201. A saturated solution of the test
substance (Water Soluble Fraction) was prepared with algal growth
medium. Repeated dilutions of the WSF resulted in a testing
concentration series of 0, 0.003, 0.01, 0.03, 0.3, 9.9, 33 and 99 % of
the WSF of MMT(EHMA) in algal growth medium. It was concluded that the
ErC50 value >1840 µg MMT(EHMA)/l, based on the geometric mean of the
measured tin concentrations is the best estimate of the mean effect
concentration of MMT(EHMA) to the fresh water algae Scendesmus
subspicatus. The NOEC value in the S. subspicatus test system was 95 µg
as tin/L, which is equivalent to 595 µg/L.
Toxicity to algae: ErC50 >1840 µg/L in Scenedesmus subspicatus; NOEC 595 µg/L (OECD 201)
The toxicity to the freshwater green alga Scenedesmus subspicatus was
determined in a 72 hour OECD 201 study. Of several parametric models
available, the model that assumes an effect on the growth rate and
exponential growth (ErC50 values) appeared to fit the data. The EC50
with respect to growth rate and geometric mean (ErC50) was found to be
>1840 µg/L. The average specific growth rate and percentage inhibition
were determined. The highest concentration that produced no oberservable
effects was 595 µg/L. However, the effects found gave no consistent
concentration effect relationship.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
Welcome to the ECHA website. This site is not fully supported in Internet Explorer 7 (and earlier versions). Please upgrade your Internet Explorer to a newer version.
Do not show this message again