Amines, N-C16-22-alkyltrimethylenedi-

Toxicity to aquatic algae and cyanobacteria

Description of key information

The toxicity to algae was tested according to OECD guideline 201 under GLP. The ErC50 was observed to be 0.15 mg/L and the ErC10 was observed to be 0.08 mg/L. Therefore Amines, N-C16-22-alkyltrimethylenedi was considered to be toxic to aquatic algae.

Key value for chemical safety assessment

EC50 for freshwater algae:

0.15 mg/L

EC10 or NOEC for freshwater algae:

0.08 mg/L

Additional information

The toxicity of Amines, N-C16-22-alkyltrimethylenedi to the unicellular freshwater green alga Pseudokirchneriella subcapitata was determined in accordance with OECD Test Guideline 201 and GLP requirements (Doig, 2013). Specific modifications to the guideline were that natural surface water was used for testing. Chemical analysis of test samples taken at 0 and 72 h indicated that concentrations of test substance were maintained within the range 29% to 42% of the initial measured values over the 72 h test period.The 72 hour ErC10 was calculated as 0.08 mg/L and the ErC50 as 0.15 mg/L, expressed as geometric mean measured concentrations.

The toxicity of N-C12 -14 -alkyltrimethylenediamines (CAS No. 90640-43-0) to algae was determined in the same conditions than performed with N-C16 -22 -alkyltrimethylenediamine (Noack, 2009). The concentrations of test substance were analysed at all concentration levels at test start and test end via LC-MS/MS analysis. The measured concentrations at test start were in the range of 100 - 132 % of the nominal values. At the end of the test N-C12-14-alkyltrimethylenediamines gave recoveries of below the limit of quantification (LOQ) to 8 % of the nominal values. Biodegradation as possible reason for this decrease is very unlikely considering the short time frame, also the river water was frozen before use to minimize the microbial activity. The decrease was attributed to additional sorption to suspended matter and DOC due to thermodynamically driven redistribution of the sorbed fraction. Therefore all effect values are given based on nominal concentrations of the test item. The 72 hour ErC10 was calculated as 40.6 µg/L and the ErC50 as 0.15 mg/L. A similar toxicity test was performed with C18-unsatd-1,3-diaminopropane (CAS 7173 -62 -8) to Desmodesmus subspicatus (Noack, 2008a). The concentrations of test substance were analysed at all concentration levels at test start and test end via LC-MS/MS analysis. The measured concentrations at test start were in the range of 91 to 98 % of the nominal values. At the end of the test recoveries were below the limit of quantification up to 12 % of the nominal values. As for N-C12 -14 -alkyltrimethylenediamines, it was considered that the test organisms were fully exposed to the test substance during the test and thus all effect values were given based on nominal concentrations of the test item. The 72 h ErC10 was188 µg/L and the 72 h ErC50 507 µg/L. Finally, toxicity test was performed with C16 -18 and C18 -saturated-1,3 -diaminopropane (CAS 133779 -11 -0) to Desmodesmus subspicatus (Noack, 2008b). The measured concentrations of test substance at test start were in the range of 92 - 135 % of the nominal values and 24 -28% at the end of the test. As for C12 -14 and C18-unsatd-1,3-diaminopropanes, the all effect values are given based on nominal concentrations of the test item. The ErC50 was observed to be 596 µg/L and the ErC10 was observed to be 193 µg/L.