The findings, part of the second report of the First Hong Kong Total Diet Study, revealed dietary exposure of the local population to inorganic arsenic fell within the mid-range of levels found in other developed nations.
Of all the samples tested by the center, 51% tested positive for inorganic arsenic. In all, the center tested a total of 600 composite samples composed of 150 different foods with three purchases collected and prepared on each of the four occasions from March 2010 to February 2011.
Better off? More the exposure
According to the report, the dietary exposures to inorganic arsenic were 0.22 and 0.38mg/kg bw/day for average and high consumer of the population, respectively.
Those of the individual age-gender population subgroups ranged from 0.19 to 0.26mg/kg bw/day and from 0.33 to 0.46mg/kg bw/day for average and high consumers, respectively, the report said.
Chief among the positive tested samples were eggs and egg products (23mg/kg), followed by fish and fish products (15mg/kg), vegetable and vegetable products (9mg/kg), and finally cereals and cereal products (8mg/kg).
Rice concerns
Interestingly, while the report revealed that dairy and dairy products, and other fats and oils contained no inorganic arsenic, rice was easily the biggest culprit of all contributing to about 54% of the total exposure.
“Rice is the major contributor of the dietary exposure to inorganic arsenic, in which the cooked white rice alone accounted for 45.2% of total exposure. This finding that rice was the major contributor were consistent with data reported in other countries where rice is the staple food,” the center said.
At food item level, water spinach was found to contain the highest level (75mg/kg), followed by salted egg (58mg/kg) and oyster (58mg/kg), whereas no water sample from the study has been detected with inorganic arsenic.
“The findings of the current study are not sufficient to warrant changes in basic dietary advice on healthy eating. Have a balanced diet, and take cereals, such as rice, noodles, oatmeal and bread, as the major dietary source,” the center said.
The report advised individuals who wish to reduce the exposure to inorganic arsenic, can consider choosing more other cereals, which generally contain lower levels of inorganic arsenic than rice, as part of their diet.