Keywords: trace analytics toxicity stream pyrethroids Insecticides Systems: stream Substances: Bifenthrin (OXCDWLBJSLVWHB-LKRLXIKPSA-N) Chlorpyrifos (SBPBAQFWLVIOKP-UHFFFAOYSA-N) Acrinathrin (YLFSVIMMRPNPFK-WEQBUNFVSA-N) Cyfluthrin (OFHFONYRMVKULH-WNYJFNBPSA-N)