EC Nutrition

Rice (Oryza sativa) is a potential dietary source of toxic arsenic. Rice accumulates ten times higher inorganic arsenic, a human car- cinogen than other grains. It is one of the most consumed food crop not only in Kenya but worldwide. Human exposure to arsenic is of great concern. There is need for continual analysis of arsenic in rice. The main purpose for the study was to determine the content of arsenic in locally produced and imported rice. Locally produced rice was sampled from Ahero and Mwea Irrigation schemes, Kenya. The varieties of imported rice from Thailand, Pakistani and India were sampled from market outlets in Nairobi County, Kenya. The analysis was done using Hydride Generation Atomic Absorption Spectrometry (HG-AAS). The results showed that arsenic content in Kenyan ordinary grain (Sindano) and Basmati (Pishori) rice gave an average of 0.059043 ± 0.04 and 0.037124 ± 0.03 mg/kg respec- tively. Arsenic content in imported Basmati rice from Thailand, Pakistan and India showed average means of 0.1259 ± 0.01, 0.0746 ± 0.01 and 0.062167 ± 0.02 respectively. Arsenic content in the imported Sindano variety from Thailand, Pakistan and India 0.15266 ± 0.02, 0.175 ± 0.02 and 0.088372 ± 0.02 mg/kg respectively. Basmati rice from Thailand had significantly higher levels of arsenic than Basmati rice from Kenya. There was significant difference (P < 0.05) in arsenic content of locally produced rice from the imported rice (P < 0.05). However, there was no significant difference in levels of arsenic in the locally produced Sindano and Pishori rice varieties (P > 0.05). The levels were found to be below the WHO recommended levels of 1.0 mg/kg

keywords: Arsenic; Hydride Generation Atomic Absorption spectrometry (HG-AAS); Rice

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