Arsenic Problems

Arsenic contamination in water is a grave concern in the national and international perspective. The problem of arsenic contamination in water in general and in ground water in particular in some parts of India and other countries has been reported as world’s biggest episode of arsenic pollution.

Conservation of sources and management of groundwater quality, therefore, have become the need of the time. Attempts has been made to present information about arsenic pollution and give a state of art of arsenic pollution. Some remedial measures to overcome the problem of arsenic pollution have also been discussed.

Redox reactions exert major controls on the occurrence of nitrate, chromate and arsenate in ground water. Nitrate levels can be lowered by denitrification in the presence of soil biota or by electron donors like pyrite in deep aquifers.

Cr(VI) and As(V) species, on the other hand, are strongly adsorbed an positively charged surfaces of iron hydroxide minerals. However, their retention is affected when competing anions are supplied through increase in salinity or fertilizer application.