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ARS Home » Southeast Area » New Orleans, Louisiana » Southern Regional Research Center » Commodity Utilization Research » Research » Publications at this Location » Publication #354038
Title: Leaf aging effects on copper and cadmium transfer along the lettuce-snail food chain

Author
item WANG, YI-MIN - Hohai University
item ZHANG, HUI - Hohai University
item XIONG, YU-TING - Hohai University
item ZHU, QIAN - Hohai University
item DING, YU-CHEN - Hohai University
item ZHAO, SHUAI - Hohai University
item ZHANG, XIAO-HUI - Hohai University
item Uchimiya, Sophie
item YUAN, XU-YIN - Hohai University

Submitted to: Chemosphere
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/23/2018
Publication Date: 7/23/2018
Citation: Wang, Y.-M., Zhang, H., Xiong, Y.-T., Zhu, Q., Ding, Y.-C., Zhao, S., Zhang, X.-H., Uchimiya, M., Yuan, X.-Y. 2018. Leaf aging effects on copper and cadmium transfer along the lettuce-snail food chain. Chemosphere. 211:81-88.

Interpretive Summary: Toxicity and trophic transfer (accumulation in the ecological food chain) vary greatly depending on the type of heavy metal contaminant affecting the agricultural soils. This study systematically compared the transfer of copper and cadmium heavy metal contaminants from soil to food crop (root and leaves of lettuce) to different organs of snails feeding on lettuce. Leaf age and sensitivity of heavy metal to ligand complexation influenced the lability of transferred contaminants (Cd or Cu species) and their transfer up the food chain. Results could be used to predict the ecological impact of leaf aging on the contaminant cycles.

Technical Abstract: Metal bioavailability at root plasma membrane surfaces putatively controls the trophic transfer processes. Accumulation of different Cu and Cd species were investigated as a function of lettuce leaf aging through soil-solution culture experiments. Metal contents in snail tissues were examined after fed on young or old age leaves for 15d, respectively. In both roots and leaves, Cu concentration was higher than Cd concentration. Young leaves accumulated more Cu than the old leaves, while the opposite trend was observed for Cd. Copper had a higher transfer factor (TF) value than Cd in biomagnification from lettuce leaf to snail. Distinctions involved in metal chemical forms within cells at different leaf ages, where higher percentages of metal in toxicity and migration associated fractions (Fi: inorganic form, Fii: water-soluble form and Fiii: pectate- and protein- integrated form) are found for Cu in old leaves and Cd in young leaves. Metal activities at root plasma membrane surfaces ({M2+}0) and chemical forms in F(i)-F(iii) linearly correlated with metal accumulation in lettuce and snail tissues (r2 > 0.900, p < 0.001 for snails fed on old leaves). This study incorporated both the chemical form approach and {M2+}0 into evaluating the trophic bioavailability of different metals along the lettuce-snail chain, which is important for mechanistic understanding of metal behaviors in the ecosystem.