| heavy metal levels and esterase variations between metal-exposed and unexposed duckweed lemna minor: field and laboratory studies. | environmental homogeneity is being continuously disturbed and affected by artificially introduced loads of chemical toxicants that also include heavy metals. the tiljala wetlands of the eastern fringe of calcutta, west bengal (india) are a virtual sink for the deposition of urban and industrial wastes that get admixed with the aquatic environment. we have selected lemna minor (duckweed), as a representative of the biota surviving therein for the present study. concentrations of lead, cadmium, ch ... | 2004 | 15120200 |