According to recent study, arsenic contamination in paddy is rising from ground water in West Bengal. It reveals that rise in arsenic contamination of paddy plants due to concentration of arsenic accumulation depends on variety of paddy and its stage in crop cycle. Its concentration varies with rice variety and stage in crop cycle.
The study was carried out on two commonly consumed rice varieties — Minikit and Jaya — and it was found that latter to be more resistant to arsenic. It shows processes and dependencies of arsenic trans-location in rice from contaminated irrigation water.
It has found that arsenic contamination in paddy was higher than in previous studies. It shows that arsenic uptake in paddy plant reduces from root to grain and that its concentration is related to variety of rice cultivated. It was observed that highest concentration of arsenic was observed in initial or vegetative state in first 28 days. It reduced during reproductive stage (29-56 days) and again increased in ripening stage.
The uptake of arsenic is faster in young roots in vegetative state than in older tissues with higher concentrations of iron in root soil in reproductive phase. It also raised concerns over disposal of contaminated rice straw which is used as animal fodder or burnt or sometimes left in field itself to serve as fertiliser.
Arsenic is a natural component in Earth’s crust. It is widely distributed throughout environment in air, water and land. It is highly toxic in its inorganic form. Intake of soluble inorganic arsenic over long period can lead to chronic arsenic poisoning (arsenicosis), diabetes, cardiovascular diseases and cancer. In India, Arsenic pollution big problem in West Bengal and neighbouring states. In West Bengal, there are 83 blocks in eight districts where groundwater is arsenic contaminated. Malda, Murshidabad and Nadia districts have higher levels of arsenic concentration.