Determination of Total Mercury in Muscle Tissues of Marine Fish Species by Ultrasonic Assisted Extraction Followed by Cold Vapor Atomic Absorption Spectrometry

A simple and rapid ultrasonic assisted extraction procedure (UEP) was developed for the determination of total mercury (Hg) in muscle tissues of marine fish species. For this purpose four fish species were collected from fish markets of Karachi, Pakistan. Total Hg concentration was determined by cold vapor atomic absorption spectrometry (CV-AAS), following UEP. Certified reference material DORM-2 (dogfish muscle) was used to validate the results. No significant difference was observed between the experimental results and the certified values of CRM (paired t-test). The limit of detection (LOD) and limit of quantitation (LOQ) of Hg were 0.133 and 0.445 μg/kg respectively. The Hg concentration in muscle tissues were obtained in the range of 0.721 – 1.41 mg/kg on dry weight. The contribution of the daily intake of Hg, based on the consumption of 250 g fresh fish muscles per day was found in the range of 0.615 – 1.22 μg/kg body weight/ day, which is greater than WHO permissible limit.