title: Assessing the Fate of an Aromatic Hydrocarbon Fluid in Agricultural Spray Applications Using the Three-Stage ADVOCATE Model Framework.
abstract: Components of emulsifiable concentrates (ECs) used in pesticide formulations may be emitted to air following application in agricultural use and contribute to ozone formation. A key consideration is the fraction of the ECs that is volatilized. This study is designed to provide a mechanistic model framework for estimating emissions of an aromatic hydrocarbon fluid used in ECs based on the results of spray chamber experiments that simulate fate as the fluids become subject to volatilization, sorption to soil, and biodegradation. The results indicate the need to treat the volatilization losses in three stages: (i) losses during spraying, (ii) losses up to 12 h after spraying in which the soil is coated with the ECs, and (iii) subsequent longer term losses in which the ECs become increasingly sorbed and subject to biodegradation. A mass balance model, the agrochemical derived volatile organic compound air transfer evaluation (ADVOCATE) tool, is developed, treating the ECs as seven hydrocarbon component groups, to estimate the volatilization and biodegradation losses using parameters fitted to empirical data. This enables losses to be estimated for each hydrocarbon component under field conditions, thereby providing a basis for improved estimation of ozone formation potential and for designing ECs that have lower emissions.
authors.affiliation: †LTEC, Wroxeter, Ontario, Canada.
authors.forename: Liisa
authors.initials: L
authors.lastname: Toose
authors.forename: Christopher
authors.initials: C
authors.lastname: Warren
authors.affiliation: §Canadian Centre for Environmental Modelling and Chemistry, Trent University, Peterborough, Ontario, Canada.
authors.forename: Donald
authors.initials: D
authors.lastname: Mackay
authors.affiliation: ΔExxonMobil Biomedical Sciences, Inc., 22777 Springwood Village Parkway, Spring, Texas 77339, United States.
authors.forename: Thomas
authors.initials: T
authors.lastname: Parkerton
authors.affiliation: ⊥ExxonMobil Biomedical Sciences, Inc., 1545 U.S. Highway 22 East Annandale, New Jersey 08801, United States.
authors.forename: Daniel
authors.initials: D
authors.lastname: Letinski
authors.affiliation: ⊥ExxonMobil Biomedical Sciences, Inc., 1545 U.S. Highway 22 East Annandale, New Jersey 08801, United States.
authors.forename: Ryan
authors.initials: R
authors.lastname: Manning
authors.affiliation: ⊥ExxonMobil Biomedical Sciences, Inc., 1545 U.S. Highway 22 East Annandale, New Jersey 08801, United States.
authors.forename: Martin
authors.initials: M
authors.lastname: Connelly
authors.affiliation: ⊗̂CONCAWE, Boulevard du Souverain 165, B-1160 Brussels, Belgium.
authors.forename: Arlean
authors.initials: A
authors.lastname: Rohde
authors.forename: Brad
authors.initials: B
authors.lastname: Fritz
authors.forename: W Clint
authors.initials: WC
authors.lastname: Hoffmann
mesh_terms: D000383:Agriculture; D006841:Hydrocarbons, Aromatic / Q000737:chemistry*; D007700:Kinetics; D008962:Models, Theoretical; D010575:Pesticides / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry*; D014835:Volatilization
chemical_list: D006841:Hydrocarbons, Aromatic; D010575:Pesticides; D012989:Soil Pollutants
keywords: biodegradation; emulsifiable concentrate; ozone; pesticide formulation; volatilization