(2RS,3RS)-3-(2-chlorophenyl)-2-(4-fluorophenyl)-[(1H-1,2,4-triazol-1-yl)methyl]oxirane

Short-term toxicity to fish

Description of key information

The test substance is acutely toxic to fish.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

3.2 mg/L

Additional information

The acute toxicity of epoxiconazole to fish was assessed with the weight-of-evidence approach. This approach is consisting of three GLP studies, conducted according to EPA OPP 72-1 (Fish Acute Toxicity Test). A trout, a bluegill and a carp were used as test organisms in these static studies. These three acute fish tests were performed in the same laboratory and in the same timeframe and with identical study conditions. Acetone was used as a solvent in all tests. In the acute fish studies, some test concentrations were chosen, which are above the determined water solubility of 7.1 mg/L. However, different ecotoxicological studies show that in standard test media solubility of the test substance can increase up to 10 mg/L. Although unexpected precipitation is observed in test concentrations ≥3.16 or ≥4.64 mg/L, analytical concentration control confirms the recovery of ~80-100% of the nominal test concentrations. The endpoints values are presented as nominal in the acute studies with O. mykiss and L. macrochirus. Since some of the measured test concentrations are below < 80% recovery, endpoints can be based on mean measured test concentrations instead. Therefore, the endpoints based on the nominal concentrations were statistically re-calculated using ToxRat v 3.2.1. The table below summarizes the endpoints for the three acute fish studies based on nominal and re-calculated mean measured test concentrations.

Table. 1 Summary of the effects in acute fish studies for exposiconazole.

Test organism	96-h LC50 (nominal) [mg/L]	96-h LC50 (mean measured) [mg/L]	Reference
O. mykiss	3.14	3.20	BASF AG, rep. no.: 12F0959/885095, 1989
L. macrochirus	5.62	5.03	BASF AG, rep. no.: 14F0959/885056, 1989
C. carpio	-	8.27	BASF AG, rep. no.: 12F0959/885095, 1989

 

Overall, based on the available experimental weight-of-evidence data for the test substance, it can be concluded that the revealed 96-h LC50 is in the range between 3.2 and 8.27 mg/L. Therefore, it can be considered that expoxiconazole is acutely toxic to fish.