Registration Dossier

Diss Factsheets

Ecotoxicological information

Sediment toxicity

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

The chlorinated isocyanurates are unstable in the environment, because the free available chlorine is rapidly reduced.  CYA, or its salt, is the stable degradation product. Therefore, CYA, or its sodium salt, is the substance of interest for chronic ecotoxicity studies. A sediment-water chironomid toxicity test according to OECD Guideline 218 with the monosodium salt of cyanuric acid. 

Key value for chemical safety assessment

EC50 or LC50 for freshwater sediment:
756 mg/kg sediment dw
EC10, LC10 or NOEC for freshwater sediment:
756 mg/kg sediment dw

Additional information

A study was performed to assess the toxicity of the monosodium salt of cyanuric acid to the sediment dwelling larvae of Chironomus riparious (Goodband 2007).120 larvae of Chironomus riparious (six replicates of 20 larvae) were exposed to formulated spiked sediment with test material at a single concentration of 1000 mg test material/kg dry weight of sediment (equivalent to 757 mg cyanuric acid/kg dry weight of sediment) for a period of 28 days. The numbers of emerged adults were recorded daily. A further 40 larvae (two replicates of 20 larvae) were prepared and sacrificed on day 10 of the exposure to determine the 10 day larval survival and growth data. The 28 day EC50 (reduction in emergence) based on nominal test concentrations was > 1000 mg test material/kg dry weight of sediment (equivalent to 756 mg cyanuric acid/kg dry weight of sediment). The NOEC was 1000 mg test material/kg dry weight of sediment (equivalent to 756 mg cyanuric acid/kg dry weight of sediment). The EC50 (development rate) based on nominal test concentrations was > 1000 mg test material/kg dry weight of sediment (equivalent to 756 mg cyanuric acid/kg dry weight of sediment).

Categories Display