Cerium Biomagnification in a Terrestrial Food Chain: Influence of Particle Size and Growth Stage

详细信息    查看全文

• 作者：Sanghamitra Majumdar ; Jesica Trujillo-Reyes ; Jose A. Hernandez-Viezcas ; Jason C. White ; Jose R. Peralta-Videa ; Jorge L. Gardea-Torresdey
• 刊名：Environmental Science & Technology
• 出版年：2016
• 出版时间：July 5, 2016
• 年：2016
• 卷：50
• 期：13
• 页码：6782-6792
• 全文大小：552K
• 年卷期：0
• ISSN：1520-5851

文摘

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.