Metal contaminants and chloramphenicol in litopenaeus vannamei and penaeus silasi at various supply chain stages in Johor Bahru, and their health risk assessment

Abstract

Contamination by toxic metals and antibiotics (like chloramphenicol) in white shrimps can be detrimental to human health. Hence, this present research evaluated the concentrations of As, Pb, Cd and total Hg and chloramphenicol as prescribed by the Malaysian Food Act in Penaeus silasi and Litopenaeus vannamei shrimps sampled from the different supply chain stages. The sampling was made at landing sites, major markets and grocers in Johor Bahru, Johor, Malaysia during the six sampling intervals. A Perkin-Elmer Analyst PinAAcle 900T atomic absorption spectrometer equipped with graphite furnace (GFAAS) and autosampler was used for quantitating the concentrations of As, Pb, and Cd. A flow injection mercury/hydride system (FI-MHS) was utilized for analysing the total Hg. The results revealed the median As and Cd concentrations that ranged between below detection limit (bdl) - 167.5 mg/kg and bdl - 0.46 mg/kg, respectively. As for total Hg, the concentrations ranged between 0.02 - 1.13 mg/kg. Although Pb and chloramphenicol were not detected, As and total Hg concentrations varied significantly across the six sampling intervals (P < 0.05), exceeded the maximum permitted proportions prescribed by the Malaysian Food Act. Identified as P. silasi, shrimps from landing sites Mersing and Pontian had significantly higher As and total Hg concentrations than those of L. vannamei from major markets and their surrounding grocers (P < 0.05). Alarmingly, Hazard Index for P. silasi from landing sites Mersing and Pontian as well as L. vannamei from major markets and grocers exceeded 1.00. Hence, formulating suitable intervention programs and devising efficient removal technologies are paramount for benefiting the public at large.