title: Cerium Biomagnification in a Terrestrial Food Chain: Influence of Particle Size and Growth Stage.
abstract: Mass-flow modeling of engineered nanomaterials (ENMs) indicates that a major fraction of released particles partition into soils and sediments. This has aggravated the risk of contaminating agricultural fields, potentially threatening associated food webs. To assess possible ENM trophic transfer, cerium accumulation from cerium oxide nanoparticles (nano-CeO2) and their bulk equivalent (bulk-CeO2) was investigated in producers and consumers from a terrestrial food chain. Kidney bean plants (Phaseolus vulgaris var. red hawk) grown in soil contaminated with 1000-2000 mg/kg nano-CeO2 or 1000 mg/kg bulk-CeO2 were presented to Mexican bean beetles (Epilachna varivestis), which were then consumed by spined soldier bugs (Podisus maculiventris). Cerium accumulation in plant and insects was independent of particle size. After 36 days of exposure to 1000 mg/kg nano- and bulk-CeO2, roots accumulated 26 and 19 μg/g Ce, respectively, and translocated 1.02 and 1.3 μg/g Ce, respectively, to shoots. The beetle larvae feeding on nano-CeO2 exposed leaves accumulated low levels of Ce since ∼98% of Ce was excreted in contrast to bulk-CeO2. However, in nano-CeO2 exposed adults, Ce in tissues was higher than Ce excreted. Additionally, Ce content in tissues was biomagnified by a factor of 5.3 from the plants to adult beetles and further to bugs.
authors.affiliation: Department of Chemistry, The University of Texas at El Paso , 500 West University Ave., El Paso, Texas 79968, United States.|University of California's Center for Environmental Implications of Nanotechnology (UC CEIN) , El Paso, Texas 79968, United States.
authors.forename: Sanghamitra
authors.initials: S
authors.lastname: Majumdar
authors.affiliation: Department of Chemistry, The University of Texas at El Paso , 500 West University Ave., El Paso, Texas 79968, United States.
authors.forename: Jesica
authors.initials: J
authors.lastname: Trujillo-Reyes
authors.affiliation: Department of Chemistry, The University of Texas at El Paso , 500 West University Ave., El Paso, Texas 79968, United States.
authors.forename: Jose A
authors.initials: JA
authors.lastname: Hernandez-Viezcas
authors.affiliation: Department of Analytical Chemistry, The Connecticut Agricultural Experiment Station , 123 Huntington Street, New Haven, Connecticut 06504, United States.
authors.forename: Jason C
authors.initials: JC
authors.lastname: White
authors.affiliation: Department of Chemistry, The University of Texas at El Paso , 500 West University Ave., El Paso, Texas 79968, United States.|Environmental Science and Engineering Ph.D. Program, The University of Texas at El Paso , 500 West University Ave., El Paso, Texas 79968, United States.|University of California's Center for Environmental Implications of Nanotechnology (UC CEIN) , El Paso, Texas 79968, United States.
authors.forename: Jose R
authors.initials: JR
authors.lastname: Peralta-Videa
authors.affiliation: Department of Chemistry, The University of Texas at El Paso , 500 West University Ave., El Paso, Texas 79968, United States.|Environmental Science and Engineering Ph.D. Program, The University of Texas at El Paso , 500 West University Ave., El Paso, Texas 79968, United States.|University of California's Center for Environmental Implications of Nanotechnology (UC CEIN) , El Paso, Texas 79968, United States.
authors.forename: Jorge L
authors.initials: JL
authors.lastname: Gardea-Torresdey
mesh_terms: D002563:Cerium; D020387:Food Chain; D010316:Particle Size; D018517:Plant Roots; D012987:Soil
chemical_list: D012987:Soil; D002563:Cerium