Variables: concentration Keywords: stream pyrethroids Substances: Chlorpyrifos (SBPBAQFWLVIOKP-UHFFFAOYSA-N) Empenthrin (YUGWDVYLFSETPE-JLHYYAGUSA-N) Chlorpyrifos-methyl (HRBKVYFZANMGRE-UHFFFAOYSA-N) Cypermethrin (KAATUXNTWXVJKI-UHFFFAOYSA-N)