World Journal of Agricultural Sciences 5 (4): 425-431, 2009
ISSN 1817-3047
© IDOSI Publications, 2009
Corresponding Author: P. Bhattacharya, Department of Environmental Science, University of Kalyani, Kalyani- 741 235, West
Bengal, India
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Transfer of Arsenic from Groundwater and Paddy Soil toRice Plant (Oryza sativa L.):
A Micro Level Study in West Bengal, India
P. Bhattacharya, A.C. Samal, J. Majumdar and S.C. Santra
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Department of Environmental Science, University of Kalyani, West Bengal, India
Abstract: Rice (Oryza sativa L.) is one of the major food crops in many countries. As the cultivation of rice
requires huge volume of water, long term use of arsenic contaminated groundwater for irrigation may result in
the increase of arsenic concentration in the agricultural soil and eventually accumulation in rice plants. Thus
a micro level study was conducted to investigate the transfer of arsenic from irrigation water and soil to rice
plants in the arsenic affected 17 villages of Chakdaha block, Nadia district, West Bengal, India. Results showed
that the level of arsenic in irrigation water (0.11±0.012 and 0.76±0.014 mg lG ) was very much above the WHO
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permissible limit of 0.01 mg lG for drinking water and was also above the FAO permissible limit of 0.10 mg lG
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for irrigation water. The paddy soil gets contaminated by the irrigation water and thus enhances more probable
condition for bioaccumulation of arsenic in rice plants. The total soil arsenic concentrations ranged from
1.38±0.108 to 12.27±0.094 mg kgG dry weight of arsenic, which was below the maximum acceptable limit for
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agricultural soil of 20.0 mg kgG as recommended by the European Community. In the rice plant, the highest
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accumulation of arsenic was noticed in the root (7.19±0.166 to 18.63±0.155 mg kgG ) and the lowest in the grain
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(0.25±0.014 to 0.73±0.009 mg kgG ). Regardless of the sampling locations the arsenic accumulation follows the
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order of root > straw > husk > grain. Consumption of rice straw containing considerable amount of arsenic
(1.17±0.014 to 4.15±0.033) by cattle could potentially lead to increased arsenic levels in meat or milk. As because
the total amount of arsenic in raw rice is not taken in human body due to its distribution in root, straw, husk and
grain parts and also because in any rice sample from the study area concentration of arsenic in the grain part
did not exceed 1.0 mg kgG dry weight of arsenic (the permissible limit of arsenic in rice according to WHO
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recommendation), thus atleast for now rice has remained harmless for consumption in the study area. But the
results clearly showed that the arsenic content in rice plant is correlated to the degree of arsenic contamination
of irrigation water and soil.
Key words: Arsenic, Bioaccumulation, Rice (Oryza sativa L.), Irrigation water, West bengal
INTRODUCTION [6,7]. So, there is a possibility of transfer of arsenic
Groundwater arsenic contamination in the Bengal (Oryza sativa L).
Delta Plain has been termed as the largest mass poisoning Arsenic accumulation in rice is viewed as a newly
in history of human kind [1]. Groundwater of nine out of recognized disaster for South-East Asia, where rice is a
total eighteen districts of West Bengal has been staple food [8]. Rahman et al. [7] reported that regardless
contaminated with arsenic [2, 3, 4]. Among them, the of rice varieties, accumulation of arsenic was 28 and
groundwater arsenic concentration in Nadia district is of 75 folds higher in root than that of shoot and raw
deep concern in terms of level of arsenic and area rice grain, respectively. This trend of higher arsenic
coverage [4]. Anthropogenic activities, such as pesticide accumulation in root was found to be concurrent with
and herbicide applications, mining and irrigation with the reports by Samal [4], Abedin et al. [9] and Liu et al.
contaminated groundwater have significantly enhanced [10]. Abedin et al. [9] reported accumulation of arsenic
arsenic levels in agricultural soil in many parts of the (upto 92.0 mg kgG ) in rice straw through a green house
world [5]. There are various reports about the elevation of pot experiment. The presence of high levels of arsenic in
arsenic concentration in agricultural fields of West Bengal the rice straw is a potential threat to cattle that consume
from contaminated irrigation water and soil to rice plant
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