Effect of cooking method and rice type on arsenic concentration in cooked rice and the estimation of arsenic dietary intake in a rural village in West Bengal, India

Abstract

Arsenic (As) contamination of rice plants can result in high total As concentrations (t-As) in cooked rice, especially if As-contaminated water is used for cooking. This study examines two variables: (1) the cooking method (water volume and inclusion of a washing step); and (2) the rice type (atab and boiled). Cooking water and raw atab and boiled rice contained 40 μg As l⁻¹ and 185 and 315 μg As kg⁻¹, respectively. In general, all cooking methods increased t-As from the levels in raw rice; however, raw boiled rice decreased its t-As by 12.7% when cooked by the traditional method, but increased by 15.9% or 23.5% when cooked by the intermediate or contemporary methods, respectively. Based on the best possible scenario (the traditional cooking method leading to the lowest level of contamination, and the atab rice type with the lowest As content), t-As daily intake was estimated to be 328 μg, which was twice the tolerable daily intake of 150 μg.

Keywords:

• atab rice
• Calcutta
• inorganic arsenic
• North 24-Parganas
• total arsenic

Acknowledgements

The paper was produced with the financial assistance of the European Union (Development of a Low Cost Technology for In-situ Treatment of Groundwater for Potable and Irrigation Purposes, TIPOT, ASI/B7301/2598/24-2004/79013), the Spanish Government MEC (CTM2005-2425-E), the Valencian Government GV (AE05/056), and Caja de Ahorros del Mediterráneo (CAM-2007). The contents of this paper are the sole responsibility of UMH and under no circumstances can be regarded as reflecting the positions of the European Union, Spanish/Valencian governments and/or CAM.