Internal distribution of Cd in lettuce and resulting effects on Cd trophic transfer to the snail: Achatina fulica.
The mechanisms underlying Cd trophic transfer along the soil-lettuce-snail food chain were investigated. The fate of Cd within cells, revealed by assessment of Cd chemical forms and of subcellular partitioning, differed between the two examined lettuce species that we examined (L. longifolia and L. crispa). The species-specific internal Cd fate not only influenced Cd burdens in lettuce, with higher Cd levels in L. crispa, but also affected Cd transfer efficiency to the consumer snail (Achatina fulica). Especially, the incorporation of Cd chemical forms (Cd in the inorganic, water-soluble and pectates and protein-integrated forms) in lettuce could best explain Cd trophic transfer, when compared to dietary Cd levels alone and/or subcellular Cd partitioning. Trophically available metal on the subcellular partitioning base failed to shed light on Cd transfer in this study. After 28-d of exposure, most Cd was trapped in the viscera of Achatina fulica, and cadmium bio-magnification was noted in the snails, as the transfer factor of lettuce-to-snail soft tissue was larger than one. This study provides a first step to apply a chemical speciation approach to dictate the trophic bioavailability of Cd through the soil-plant-snail system, which might be an important pre-requisite for mechanistic understanding of metal trophic transfer.
Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
Cheng-Cheng
CC
Li
Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, PR China.
Fei
F
Dang
Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, PR China.
Long
L
Cang
Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, PR China. Electronic address: dmzhou@issas.ac.cn.
Dong-Mei
DM
Zhou
National Institute of Public Health and the Environment (RIVM), Center for Safety of Substances and Products, 3720 BA Bilthoven, The Netherlands; Institute of Environmental Sciences (CML), Leiden University, 2300 RA Leiden, The Netherlands.
Willie J G M
WJ
Peijnenburg
D000818:Animals; D002104:Cadmium / Q000378:metabolism*; D004784:Environmental Monitoring; D020387:Food Chain; D006372:Helix, Snails / Q000378:metabolism; D018545:Lactuca / Q000378:metabolism*; D008670:Metals / Q000378:metabolism; D012908:Snails / Q000378:metabolism; D012987:Soil; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism*
D008670:Metals; D012987:Soil; D012989:Soil Pollutants; D002104:Cadmium
Achatina fulica; Cadmium; Chemical forms; Food chain; Lactuca sativa; Subcellular distribution