Multiple approaches to assess human health risks from carcinogenic and non-carcinogenic metals via consumption of five fish species from a large reservoir in Turkey

Highlights: • Metal concentrations in fish species were below the maximum permissible levels. • EDI, THQ, TTHQ and CR were estimated for non-carcinogenic and carcinogenic risks. • Fish consumption limits were determined to minimize risks to human health. Keban Dam Reservoir (KDR), located on the Euphrates River (Turkey), is an internationally important reservoir. In this study, levels of ten metals in 220 muscle samples of five fish species (mangar, common carp, Tigris scraper, Euphrates barbell and trout barb) taken from 11 sampling sites in the KDR were determined and compared with the results of previous studies carried out in other countries and Turkey. In addition, multiple approaches were used to assess human health risks from fish consumption. The significant spatial differences in concentrations of studied metals except As and Ni in Euphrates barbell were not found. However, concentrations of all metals except Cd showed significant seasonal differences. The concentrations of ten metals in fish species were lower than or comparable to those in fish species from other freshwater bodies. The metal concentrations in all fish species were found below the maximum permissible concentrations. No health risks of studied heavy metals on human were found by daily fish intake. The target hazard quotient (THQ) and total THQ values were below 1, which suggests there are no significant non-carcinogenic health risks for fish consumers. The cancer risk values calculated for inorganic arsenic in all fish species except Euphrates barbell did not exceed the 10⁻⁶ threshold. The allowable number of fish meals per month can be categorized as safe fish consumption. The results of this study revealed that the consumption of the examined fish species does not pose a significant risk to human health.