title: Pesticides in surface water, sediment, and rainfall of the northeastern Pantanal basin, Brazil.
abstract: Within the last 25 years an intensive agriculture has developed in the highland regions of Mato Grosso state (Brazil), which involves frequent pesticide use in highly mechanized cash-crop cultures. To provide information on pesticide distribution and dynamics in the northeastern Pantanal basin (located in southern Mato Grosso), we monitored 29 pesticides and 3 metabolites in surface water, sediment, and rainwater of the study area during the main application season. In environmental samples, 19 pesticides and 3 metabolites were detected in measurable quantities, resulting in at least one pesticide detection in 68% of surface water samples (n = 139), 62% of sediment samples (n = 26), and 87% of rainwater samples (n = 91). Surface water samples were most frequently contaminated by endosulfan compounds (alpha-, beta-, -sulfate), ametryn, metolachlor, and metribuzin, although in low (< 0.1 microgram L-1) concentrations. Sediment samples exhibited concentrations up to 4.5 micrograms kg-1 of p,p'-DDT, p,p'-DDE, endosulfan-sulfate, beta-endosulfan, and ametryn. In contrast, rainwater was polluted with substantial amounts of endosulfan, alachlor, metolachlor, trifluralin, monocrotofos, and profenofos (maximum concentrations = 0.3 to 2.3 micrograms L-1) in the highlands. Lowland rainwater samples taken 75 km from the next application area contained 5- to 10-fold lower mean pesticide concentration than in the highlands. Cumulative deposition rates of the pesticide sum within the study period ranged from 423 micrograms m-2 in the highlands to 14 micrograms m-2 in the lowlands. The atmospheric input of pesticides to ecosystems seemed to be of higher relevance in the tropical study area than known from temperate regions.
authors.affiliation: Institute of Soil Science and Soil Geography, University of Bayreuth, D-95440 Bayreuth, Germany. volker.laabs@covance.com
authors.forename: Volker
authors.initials: V
authors.lastname: Laabs
authors.forename: Wulf
authors.initials: W
authors.lastname: Amelung
authors.forename: Alicio A
authors.initials: AA
authors.lastname: Pinto
authors.forename: Matthias
authors.initials: M
authors.lastname: Wantzen
authors.forename: Carolina J
authors.initials: CJ
authors.lastname: da Silva
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Zech
mesh_terms: D000383:Agriculture; D001938:Brazil; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D010575:Pesticides / Q000032:analysis*; D011891:Rain; D014329:Tropical Climate; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D010575:Pesticides; D014874:Water Pollutants, Chemical