Arsenic and cadmium in food-chain in Bangladesh--an exploratory study.
Arsenic contamination of tubewell water is a major public-health problem in Bangladesh. In the recent years, the use of shallow and deep tubewell water for irrigation and the use of excess amount of cheap fertilizers and pesticides containing cadmium pose a serious threat of contamination of arsenic and cadmium in food. In an exploratory study, arsenic and cadmium were measured in foods from Matlab, a rural area in Bangladesh, that is extensively affected by arsenic and the economy is agriculture-based. Raw and cooked food samples were collected from village homes (households, n=13) and analyzed to quantify concentrations of arsenic and cadmium using atomic absorption spectrophotometry. Washing rice with water before cooking reduced the concentration of arsenic in raw rice by 13-15%. Rice, when cooked with excess water discarded, showed a significant decrease in arsenic concentration compared to that cooked without discarding the water (p<0.001). In contrast, concentration of cadmium did not decrease in cooked rice after discarding water. Cooked rice with discarded water had significantly lower concentration of arsenic compared to raw rice (p=0.002). Raw rice had higher concentration of arsenic compared to raw vegetables (p<0.001); however, no such difference was found for cadmium. Compared to raw vegetables (e.g. arum), concentration of arsenic increased significantly (p=0.024) when cooked with arsenic-contaminated water. Thus, the practice of discarding excess water while cooking rice reduces the concentration of arsenic but not of cadmium in cooked rice. However, water generally not discarded when cooking vegetables to avoid loss of micronutrients consequently retains arsenic. The results suggest that arsenic and cadmium have entered the food-chain of Bangladesh, and the cooking practices influence the concentration of arsenic but not of cadmium in cooked food.
Laboratory Sciences Division, ICDDR,B, Mohakhali, Dhaka 1212, Bangladesh.
Shafiqul Islam
SI
Khan
A K Mottashir
AK
Ahmed
Mohammad
M
Yunus
Mahfuzar
M
Rahman
Samar Kumar
SK
Hore
Marie
M
Vahter
M A
MA
Wahed
D001151:Arsenic / Q000032:analysis*; D001459:Bangladesh; D002104:Cadmium / Q000032:analysis*; D003296:Cooking / Q000379:methods; D005504:Food Analysis; D020387:Food Chain; D005506:Food Contamination / Q000517:prevention & control; D010865:Pilot Projects; D012423:Rural Health
D002104:Cadmium; D001151:Arsenic
Proc Natl Acad Sci U S A. 2000 Apr 25;97(9):4991-6
10781110
J Health Popul Nutr. 2006 Mar;24(1):36-41
16796148
J Occup Med Toxicol. 2006 Sep 10;1:22
16961932
Altern Med Rev. 2003 May;8(2):106-28
12777158
J Anim Sci. 1991 Oct;69(10):4078-87
1778821
Environ Health Perspect. 1979 Feb;28:59-66
488049
Nature. 1997 Jul 31;388(6641):482-8
9242408
Environ Sci Technol. 2008 Aug 1;42(15):5574-9
18754478
Bull World Health Organ. 2000;78(9):1093-103
11019458
Gastroenterology. 1978 May;74(5 Pt 1):841-6
640339
J Epidemiol Community Health. 2006 Mar;60(3):242-8
16476755
Environ Sci Technol. 2003 Jan 15;37(2):229-34
12564892
Occup Environ Med. 1997 Oct;54(10):750-5
9404324
Food Chem Toxicol. 2006 Nov;44(11):1823-9
16876928
Lancet. 2002 Dec 7;360(9348):1839-40
12480363
J Anim Sci. 1991 Oct;69(10):4088-96
1778822
Environ Health Perspect. 2004 Aug;112(11):1172-7
15289162