Mitigation of arsenic in rice through deficit irrigation in field and use of filtered water in kitchen

Abstract

An experiment was conducted in an arsenic-affected area of West Bengal, India, with the aim of alleviating arsenic toxicity from food chain through water management in rice field and modification of cooking procedure of the same grain in kitchen. Three regimes of deficit irrigation, viz. intermittent ponding, saturation and aerobic condition were tested in field against continuous ponding, i.e. local farmers’ practice. Produced grains were cooked in traditional method with both arsenic-contaminated and filtered water. Results revealed that deficit irrigation can be efficiently used to reduce the arsenic load in rice grain. Water management in field can reduce 9–21 % arsenic content in raw rice grain and can save 150–340 mm of irrigation water over traditional cultivation procedure. Furthermore, use of filtered water for cooking can alleviate up to 32 % of arsenic. The study also revealed that growing rice under deficit irrigation can also increase the water use efficiency of the crop.