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Health risk assessment of trace metals from groundwater in the deltaic plain of

Bangladesh.

According to WHO the maximum permissible limits of heavy metals in soil and plants are as follows

Nickel- plants 10mg/kg

Water 0.2mg/l

Chromium- plants 1.30 mg/kg

Water 0.1 mg/l

Cadmium - plants 0.02mg/kg

Water 0.01 mg/l

Copper- plants 10mg/kg

Water 2mg/l

Lead- plants 2mg/kg

Water 0.05 mg/l

Iron- plants 20 mg/kg

Water 1 mg/l

Zinc- plants 50 mg/kg

Water 5mg/l