TOXICOCHEMICAL ANALYSIS OF ARSENIC IN BROILER CHICKEN; IMPLICATIONS FOR HUMAN RISK ASSESSMENT

Abstract

Among the general public, the word „„arsenic” has become almost synonymous with the word„„poison” because of its toxic nature to humans. Although there has been considerable concern about the adverse effect of arsenic present in drinking water, the risks of arsenic in food have received less attention. The main purpose of this study was to estimate the total arsenic concentration in different tissues (breast, liver and heart) of broiler chicken in different brands available in the Sri Lankan market. Graphite furnace atomic absorption spectrometry (GF-AAS) was used subsequent to dry ash preparation with the presence of Mg(NO3)2 as the ashing aid. The accuracy of the technique was evaluated by using spiked chicken breast sample; the percentage recovery of total As was observed as 105.7%. The concentrations of total arsenic in different brands of broiler chicken were found in  the ranges of 0.65-0.85, 0.42-0.52 and not detectable-0.08 µg g-1on wet basis with respect to the brands “A”, “B” and “C”. Some of the tested breast tissue samples violated the tolerance limit (0.5 µg g-1) for total residue of arsenic in chicken meat set by the US-FDA.  These values are also higher than the values observed in a market study in the United States, during 1991–1996 and lower than the arsenic values reported in Pakistan in 2007. The variation of mean total arsenic concentrations in breasts, liver and heart tissues within the brand “C”, was observed as  0.04, 0.33 and 0.30 µg g-1on wet basis. These observations conclude that liver and heart tissues contain relatively higher amounts of total arsenic than breast tissues.

Another purpose of this study was to estimate total and inorganic arsenic ingested by humans through chicken consumption and thereby make implications for human risk assessment. Taking into account observed total arsenic concentrations of breast muscle tissues in this study and 65% from the total as inorganic arsenic, the inorganic and total arsenic ingested by eating chicken was calculated. Considering average levels of chicken consumption as 60 g/person/day, people may ingest as much as 44.90, 28.29 and 2.10 µg of total arsenic/day, which is equivalent to 29.19, 18.39 and 1.37 µg inorganic arsenic/day from brands “A”, “B” and “C”, respectively. For a person weighing 60 kg, the inorganic arsenic intake would be 0.49, 0.31, and 0.02 µg/kg/day and contributes 23.77, 14.60 and 1.09 percentages by chicken alone out of the FAO/WHO tolerable daily intake which is 2.1µg/ kg/day received from  all  dietary sources. Moreover, arsenic was tested among the cooked chicken breasts which were subjected to different cooking recipes and it was found that the cooked chicken breast tissues had total arsenic closer to 1 µg g-1; none of them were below the maximum permissible level. These studies suggest that the cooking methods do not have any impact on removing arsenic.