title: Mineralization of aged atrazine and mecoprop in soil and aquifer chalk.
abstract: The effect of ageing on the bioavailability and sorption of the herbicides atrazine and mecoprop was studied in soil and aquifer chalk sampled at an agricultural field near Aalborg, Denmark. The herbicides were incubated in sterile soil or chalk up to 3 months prior to inoculation with 5 x 10(7) cells g(-1) (dry weight) of a mecoprop degrading highly enriched culture (PM) or 1 x 10(9) cells g(-1) (dry weight) of the atrazine degrading Pseudomonas sp. strain ADP. As a measure of the bioavailable residues accumulated 14CO2 was measured for 2 months. In both soil and chalk ageing limited the rate of atrazine mineralization, and in chalk the extent of mineralization was reduced as well. The fraction of sorbed atrazine in the soil ranged between 50% and 62%, whereas a maximum of 12% was sorbed in chalk. No impact on the mineralization of aged mecoprop was seen as no sorption of this herbicide on either soil or chalk was measured.
authors.affiliation: Department of Geochemistry, Geological Survey of Denmark and Greenland, GEUS, Copenhagen, Denmark.
authors.forename: G B
authors.initials: GB
authors.lastname: Kristensen
authors.forename: H
authors.initials: H
authors.lastname: Johannesen
authors.forename: J
authors.initials: J
authors.lastname: Aamand
mesh_terms: D008456:2-Methyl-4-chlorophenoxyacetic Acid / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism*; D000042:Absorption; D000327:Adsorption; D000383:Agriculture; D001280:Atrazine / Q000737:chemistry / Q000378:metabolism*; D001682:Biological Availability; D002119:Calcium Carbonate / Q000737:chemistry; D006540:Herbicides / Q000737:chemistry / Q000378:metabolism*; D011549:Pseudomonas / Q000502:physiology; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis*
chemical_list: D006540:Herbicides; D012989:Soil Pollutants; C008340:mecoprop; D008456:2-Methyl-4-chlorophenoxyacetic Acid; D002119:Calcium Carbonate; D001280:Atrazine