title: Agricultural pesticide residues in farm ditches of the Lower Fraser Valley, British Columbia, Canada.
abstract: Transient and permanent farm ditches flowing to the Lower Fraser River tributary fish streams of British Columbia, Canada, were sampled at several locations in 2003-2004 to determine the occurrence and concentration of residues of selected pesticides, their transformation products, and soluble/extractable Cu++ ions. Of the 43 compounds analyzed, 28 and 22 pesticides were detected in transient farm ditch water and sediments, respectively. About 34% fewer pesticides, however, were found in both matrices of permanent farm ditches. Average concentrations (microg L(-1)) of those most frequently detected in permanent farm ditch water were atrazine (0.20), alpha -chlordane (0.06), desethylatrazine (0.13), diazinon (0.55), dieldrin (0.28), endosulfan sulfate (0.16), glyphosate (6), metalaxyl (0.27); and soluble Cu++ ions (25). Those most often found in ditch sediments (microg kg(-1)) were aminomethylphosphonic acid (AMPA) (2,300), 1,1,1-trichloro-2,2-bis-(4-chlorophenyl)ethane (DDT) (250), endosulfan sulfate (500), glyphosate (1,225); and extractable Cu++ ions (58,000). The risk potential of these pesticide residues to non-target aquatic organisms inhabiting Fraser River tributary fish streams contiguous to permanent farm ditches is evaluated and discussed.
authors.affiliation: Environmental Stewardship Branch, Commercial Chemicals Division and Environmental Emergencies, Environment Canada, Pacific and Yukon, Vancouver, British Columbia, Canada. MTW-Consulting@shaw.ca
authors.forename: Michael T
authors.initials: MT
authors.lastname: Wan
authors.forename: Jen-ni
authors.initials: JN
authors.lastname: Kuo
authors.forename: Brad
authors.initials: B
authors.lastname: McPherson
authors.forename: John
authors.initials: J
authors.lastname: Pasternak
mesh_terms: D000383:Agriculture; D000827:Animal Welfare; D000818:Animals; D001955:British Columbia; D005399:Fishes / Q000378:metabolism; D019015:Geologic Sediments / Q000737:chemistry*; D010573:Pesticide Residues / Q000032:analysis*; D045483:Rivers; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D010573:Pesticide Residues; D014874:Water Pollutants, Chemical