Metabolism and organ distribution of arsenic in the freshwater fish Tilapia mossambica

Arsenic concentration and arsenic speciation in the liver, intestine, ovary, bone, brain, muscle, gill and eye of the freshwater fish Tilapia mossambica exposed to arsenic were investigated. The profile of arsenic distribution in tissues of T, mossambica after exposure to a medium containing arsenate was brain > intestine > ovary > eyes > muscle > gill > bone > Liver, The minimum content of arsenic is in liver tissue (2.5 mug(As) g(-1) dry weight), whereas the maximum content is in brain tissue (61.8 mug(As), g(-1) dry weight), Arsenic accumulated in liver tissue was present as methylated arsenic species, and no inorganic arsenic species were found in liver tissue. A notable exception is in brain tissue, Most arsenic accumulated in brain tissue was inorganic arsenic species, and no methylated arsenic was found in brain tissue. In a dietary exposure treatment, the maximum arsenic accumulation in the tissue of T, massambica fed with Neocaridina denticulata dosed with arsenic from a Chlorella vulgaris diet (via the food chain) is in the ovary (7.4 mu gAs g(-1) dry weight), followed by gill, liver, muscle, bone, brain, eyes and intestine. Trace amounts of methylated arsenic were found in liver tissue in this treatment. Methylated arsenic in fish exposed via water was more evenly distributed in the organs compared with dietary exposure, Copyright (C) 2001 John Wiley & Sons, Ltd.