Clomazone is an herbicide that reduces chlorophyll and carotenoid levels in plants.1 It is used to control grasses and broad-leaved weeds but is toxic to certain aquatic wildlife with an LC50 of 7.32 mg/L for silver catfish.2 It decreases acetylcholinesterase (AChE) activity in brain and muscle tissue of the silver catfish (83 and 89% inhibition, respectively) when used at concentrations of 5, 10, and 20 mg/L. However, it increases AChE activity in muscle of the teleost fish.3
1.Kaňa, R., ?pundová, M., Ilík, P., et al.Effect of herbicide clomazone on photosynthetic processes in primary barley (Hordeum vulgare L.) leavesPestic. Biochem. Physiol.78(3)161-170(2004) 2.dos Santos Miron, D., Crestani, M., Rosa Shettinger, M., et al.Effects of the herbicides clomazone, quinclorac, and metsulfuron methyl on acetylcholinesterase activity in the silver catfish (Rhamdia quelen) (Heptapteridae)Ecotoxicol. Environ. Saf.61(3)398-403(2005) 3.Moraes, B.S., Loro, V.L., Glusczak, L., et al.Effects of four rice herbicides on some metabolic and toxicology parameters of teleost fish (Leporinus obtusidens)Chemosphere68(8)1597-1601(2007)