Heavy metals contaminant of shrimp paste products and risk assessment in Thailand

Abstract

Shrimp paste (ka-pi) is one of the fermented fishery products that has been widely consumed in Thailand, but the risk assessment of different material sources of shrimp paste is limited. This study aims to investigate the heavy metal concentration of arsenic (As), lead (Pb), cadmium (Cd), and mercury (Hg) in shrimp paste products in Thailand. Thirty shrimp paste product samples were collected from the local markets and were segregated based on the areas where raw materials were collected from. These areas include the Andaman Sea and the Gulf of Thailand. The modified method was validated by checking the linearity between instrument signal response and pure reference standard of a single element using r2 value of external standard and five concentration levels with > 0.9995. The recoveries were within 97% and 103% for all the studied metals. The Limit of Detection (LOD) ranged between 0.005 – 0.25 (mg/kg), and the Limit of Quantification (LOQ) was between 0.016 – 0.598 (mg/kg). As and Hg contaminants were found in all 30 sample products. The health-risk estimation indicated that the hazard quotient for As was the highest, and 8 out of 30 samples from both sampling areas were found to have unacceptable levels. This study presents results that the carcinogenic risk of all 30 samples from the Andaman Sea and the Gulf of Thailand had As levels higher than the acceptable limit. The findings of this study can serve as a useful baseline for taking protective measures and to reduce heavy metal contamination of shrimp paste products in Thailand. The results also suggest measures to improve the seawater quality to protect marine animals from seawater pollution.