Omega-3 Fatty Acids versus Heavy Metals: A Quantitative Estimation of the Benefit-Risk Ratio for the Consumption of Commonly-Consumed Fish and Products in Metro Manila

Abstract

Fish and other marine products consumption is the main route of heavy metal exposure to human which poses health risks if taken in high dosage. On the other hand, the nutritional benefits of fish are mainly due to the content of high-quality protein and high content of the two kinds of omega-3 polyunsaturated fatty acids (PUFA): eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The study aims to assess and compare the benefit-risk ratio for the consumption of commonly-consumed fish and products in Metro Manila. Fish and product samples were analyzed for moisture, crude fat, heavy metals (As, Cd, Pb) and fatty acid profile (saturated, mono-and polyunsaturated) including omega-3 fatty acids EPA and DHA. These findings generally indicate that the consumption of fish and products studied posed no risk to human health. Essential fatty acids EPA and DHA were highest for dried anchovy, Stolephorus indicus (1.5 and 7.3mg/g sample); mussel, Mytilus smaragdinus (1.5 and 1.0mg/g sample); round scad, Decapterus macrosoma (0.9 and 3.4mg/g sample); and skipjack tuna, Auxis thazard (1.1 and 3.9mg/g sample). The hazard quotients of essential fatty acids versus heavy metals were also less than 1 except for Cd in squid (1.8), In the case of dried sardine (19.9), squid (1.8), shrimp (3.4), and skipjack tuna (1.7), these foods should be monitored regularly. In conclusion, the target hazard quotients for most of the fish and products showed values less than 1, which suggest that health risks were insignificant.

Metal Contents in Fish from the Bay of Bengal and Potential Consumer Exposure—The EAF-Nansen Programme

“…In general, the cadmium content in the large fish species from Sri Lanka was similar to that of other large fish species sampled in the same area of the Bay of Bengal: yellowfin tuna (0.01 mg/kg), swordfish (0.09 mg/kg), black marlin (0.02 mg/kg), and red snapper (0.01 mg/kg) [59]. Of the small species sampled from Sri Lanka, considerably lower cadmium contents been reported in the literature (predominantly from other Asian countries): 0.06 mg/kg [60] and 0.03 mg/kg [61] for Auxis Thazard (0.18 mg/kg in this study), 0.04 mg/kg [60] and 0.008 mg/kg [61] for Decapterus macrosoma (mean value of 0.76 mg/kg in this study), 0.27 mg/kg [61] for Stolephorus indicus (0.51 mg/kg in this study), and 0.03 mg/kg for Rastrelliger kanagurta (0.27 mg/kg in this study) [62]. However, cadmium accumulation in fish is not homogeneous.…”