title: Pyrethroid insecticides in municipal wastewater.
abstract: Pyrethroids are widely used insecticides, but minimal information has been published on their presence in municipal wastewater in the United States. Pyrethroids in wastewater from the Sacramento, California, USA, area consisted of permethrin, bifenthrin, cypermethrin, and cyhalothrin, with a combined concentration of 200 ng/L to 500 ng/L. Sampling within the wastewater collection system leading to the treatment plant suggested pyrethroids did not originate primarily from urban runoff, but could be from any of several drain disposal practices. Wastewater from residential areas was similar in pyrethroid composition and concentration to that from the larger metropolitan area as a whole. Secondary treatment removed approximately 90% of pyrethroids, but those remaining exceeded concentrations acutely toxic to sensitive species. Toxicity to the amphipod, Hyalella azteca, was consistently evident in the final effluent. The large river into which this particular plant discharged provided sufficient dilution such that pyrethroids were undetected in the river, and there was only slight toxicity of unknown cause in 1 river sample, but effects in receiving waters elsewhere will be site-specific.
authors.affiliation: Department of Integrative Biology, University of California, Berkeley, California, USA.
authors.forename: Donald P
authors.initials: DP
authors.lastname: Weston
authors.forename: Heather L
authors.initials: HL
authors.lastname: Ramil
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Lydy
mesh_terms: D033304:Amphipoda / Q000187:drug effects; D000818:Animals; D002140:California; D007306:Insecticides / Q000032:analysis* / Q000633:toxicity; D009570:Nitriles / Q000032:analysis / Q000633:toxicity; D026023:Permethrin / Q000032:analysis / Q000633:toxicity; D011722:Pyrethrins / Q000032:analysis* / Q000633:toxicity; D045483:Rivers / Q000737:chemistry; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000633:toxicity
chemical_list: D007306:Insecticides; D009570:Nitriles; D026023:Permethrin; D011722:Pyrethrins; D062065:Wastewater; D014874:Water Pollutants, Chemical; C017160:cypermethrin; C099952:bifenthrin; C037304:cyhalothrin
keywords: Hyalella azteca; Municipal wastewater; Pyrethroid; Sewage treatment