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Ecotoxicological information

Endpoint summary

Administrative data

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Additional information

The 96 hr LC50 value for ranibow trout determined in an O.E.C.D. Testing Guideline 203 GLP study was 30 mg/L (95% Confidence Limits = 25 -36 mg/L). The 48 hr static EC50 value for Daphnia magna in an O.E.C.D. Testing guideline 202 GLP study was 47 mg/L with 95% Confidence Limits of 39 -57 mg/L. The O.E.C.D. MultiCASE QSAR model was used to estimate a 48 hr LC50 value for green algae of 23.1 mg/L. Since the QSAR estimated LC50 value is the lowest acute EC50/LC50 value, the 23.1 mg/L value is selected for derivation of freshwater and marine PNECs.

As per E.C.H.A. guidance, RIP 3.2 Chapter R.10: Characterization of dose [concentration]-response for environment an Assessment Factor of 1000 -fold is applied for derivation of the freshwater PNEC. However, an additional adjustment of two-fold is added to account for the use of QSAR modeling and study duration (48 hr vs 72 hr) resulting in a total Assessment Factor of 2,000 -fold. Therefore, the Freshwater PNEC for 1,6 -Hexanediol glycidyl ether is (23.1 mg/L)/2000 = 0.0115 mg/L or 11.5 ug/L. The corresponding marine PNEC = 0.00115 mg/L or 1.115 ug/L.

The PNEC microorganisms for Sewage Treatment Plants (STP) is based on the findings of an O.E.C.D. Testing Guideline 209 Activated Sludge Respiration Inhibition Test conducted with GLP compliance. The estimated IC50 value for 1,6-Hexanediol Diglycidylether (HDDGE) in this study was > 100 mg/L demonstrating that HDDGE is non-toxic to activated sludge microorganisms. Based on E.C.H.A. guidance, a total Assessment Factor of 100 -fold is applied resulting in a PNEC microorganisms of > 1.0 mg/L