title: Uptake and Metabolism of Phthalate Esters by Edible Plants.
abstract: Phthalate esters (PAEs) are large-volume chemicals and are found ubiquitously in soil as a result of widespread plasticulture and waste disposal. Food plants such as vegetables may take up and accumulate PAEs from soil, potentially imposing human health risks through dietary intake. In this study, we carried out a cultivation study using lettuce, strawberry, and carrot plants to determine the potential of plant uptake, translocation, and metabolism of di-n-butyl phthalate (DnBP) and di(2-ethylhexyl) phthalate (DEHP) and their primary metabolites mono-n-butyl phthalate (MnBP) and mono(2-ethylhexyl) phthalate (MEHP). All four compounds were detected in the plant tissues, with the bioconcentration factors (BCFs) ranging from 0.16 ± 0.01 to 4.78 ± 0.59. However, the test compounds were poorly translocated from roots to leaves, with a translocation factor below 1. Further, PAEs were readily transformed to their monoesters following uptake. Incubation of PAEs and monoalkyl phthalate esters (MPEs) in carrot cell culture showed that DnBP was hydrolyzed more rapidly than DEHP, while the monoesters were transformed more quickly than their parent precursors. Given the extensive metabolism of PAEs to monoesters in both whole plants and plant cells, metabolism intermediates such as MPEs should be considered when assessing human exposure via dietary intake of food produced from PAE-contaminated soils.
authors.affiliation: †Department of Environmental Sciences, University of California, Riverside, California 92521, United States.|‡College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China.
authors.forename: Jianqiang
authors.initials: J
authors.lastname: Sun
authors.affiliation: †Department of Environmental Sciences, University of California, Riverside, California 92521, United States.
authors.forename: Xiaoqin
authors.initials: X
authors.lastname: Wu
authors.affiliation: †Department of Environmental Sciences, University of California, Riverside, California 92521, United States.
authors.forename: Jay
authors.initials: J
authors.lastname: Gan
mesh_terms: D018552:Daucus carota / Q000187:drug effects / Q000378:metabolism; D003993:Dibutyl Phthalate / Q000378:metabolism / Q000493:pharmacokinetics*; D004051:Diethylhexyl Phthalate / Q000031:analogs & derivatives / Q000378:metabolism / Q000493:pharmacokinetics; D031985:Fragaria / Q000187:drug effects / Q000378:metabolism; D018545:Lactuca / Q000187:drug effects / Q000378:metabolism; D010795:Phthalic Acids / Q000378:metabolism / Q000493:pharmacokinetics*; D018515:Plant Leaves / Q000187:drug effects / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000378:metabolism; D010945:Plants, Edible / Q000187:drug effects* / Q000378:metabolism; D012037:Refuse Disposal; D012989:Soil Pollutants / Q000493:pharmacokinetics*; D014018:Tissue Distribution
chemical_list: D010795:Phthalic Acids; D012989:Soil Pollutants; D003993:Dibutyl Phthalate; D004051:Diethylhexyl Phthalate; C016599:mono-(2-ethylhexyl)phthalate