Abstract: The study aimed to investigate the status of heavy metal pollution of offshore fish and the health risk of heavy metals through consumption of offshore fish. The concentrations of plumbum (Pb), cadmium (Cd), chromium (Cr), total arsenic (As), inorganic As and total mercury (Hg) were determined in 6 tissues (head, tail, skin, bones, flesh and viscera) from 9 offshore fish species such as Decapterus macrosoma and Scomberomorus niphonius using inductively coupled plasma mass spectrometry (ICP-MS), liquid chromatography-atomic fluorescence spectrometry (LC-AFS) and atomic fluorescence spectrometry (AFS). The heavy metal pollution status of the 9 offshore fish species was estimated by calculating the pollution index and the target hazard coefficient index. The results showed that in 9 (16.67%) of the 54 groups of fish tissue samples, Cr levels exceeded the national standard limit (GB 2762-2017). In 7 (12.96%) of these groups, Cd levels exceeded the national standard limit. In 2 (3.70%) of these groups, Pb levels exceeded the national standard limit. In all groups, the concentrations of inorganic As and total Hg were lower than the national standard limits. For 7 (12.96%) of the 54 groups, heavy metal levels in fish viscera exceeded the national standard limit. For 3 (5.56%) of these groups, heavy metal levels in fish head and tail exceeded the national standard limit. Heavy metal levels in fish flesh did not exceed the standard limit for any of the groups. The single factor pollution index showed that the most serious pollution status occurred in Cr, followed in sequence by Cd and Pb, and the pollution levels of inorganic As and total Hg were the lowest. The highest comprehensive pollution index (3.877) was seen for the viscera of Sardina pilchardus suggesting a serious pollution level. The comprehensive pollution index for the viscera of D. macrosoma, S. niphonius, Pneumatophorus japonicus and Nemipterus virgatus was at the medium pollution level. The health risk indexes of single and multiple heavy metals in fish flesh from the 9 species were all less than 1, indicating that the heavy metal pollution in the viscera of offshore fish is more serious, but the fish flesh can be consumed safely. The results of this study will guide daily consumption of offshore fish and comprehensive development of by-products.

Key words: inductively coupled plasma mass spectrometry; liquid chromatography-atomic fluorescence spectrometry; atomic fluorescence spectrometry; offshore fish; heavy metals; pollution status; food safety