Mercury contamination in human hair and some marine species from Sfax coasts of Tunisia: levels and risk assessment

Abstract

The aim of this study was to measure the mercury (Hg) contents of three marine fish and common seafood species (Diplodus annularis, Sarpa salpa and Sepia officinalis) at two sampling sites in the gulf of Gabes, i.e. Sidi Mansour (polluted site) and Kerkennah (control site). These species are frequently consumed by the population living at the Sfax coasts of Tunisia, particularly by the families of fisherman. Additionally, the hair mercury levels of 55 volunteers (28 women, 27 men) were analysed and the daily total mercury intake through the fish and seafood diet was estimated. The key findings were: (1) the mercury contents of the examined fish and seafood species frequently exceeded the regulatory guideline value of 0.5 mg/kg, (2) no site-specific differences in hair mercury contents were found, (3) fish and seafood consumption is probably the major contributor of mercury exposure in this population, (4) the daily mercury intake through frequent consumption of D. annularis exceeds the US EPA reference dose. Further studies are necessary to evaluate the health risks associated with such high mercury exposure levels in order to allow optimal counseling and therapy of the concerned population and to avoid future impairment of human health, particularly children's health.

Total mercury and selenium concentrations in Sarpa salpa and Balistes capriscus and in their respective Digenean endoparasites Robphildollfusium fractum and Neoapocreadium chabaudi from Tunisia

“…Thunnus spp., Xiphias gladius), studies focusing on mercury concentrations in teleostei fish, including Sparidae and Balistidae, are much scarcer (Türkmen et al 2008;Mezghani-Chaari et al 2011). As expected, the values obtained in the present study revealed that the omnivorous species (B. capriscus) accumulates much more mercury than the herbivorous species (S. salpa).…”

“…As expected, the values obtained in the present study revealed that the omnivorous species (B. capriscus) accumulates much more mercury than the herbivorous species (S. salpa). Mezghani-Chaari et al (2011) also analysed the mercury concentration in the edible parts of two Sparidae fish (Diplodus annularis and S. salpa) from Sidi Mansour (12 Km to the north of Sfax) and reported mean concentrations of 1100 and 80 ppb wet weight, respectively. The value obtained in S. salpa by the latter authors is very similar to that observed in the present study (74.9 ppb) in the muscle of cow breams from Sfax whereas the level of mercury reported in D. annularis was higher than the herein reported in B. capriscus from Sfax (212 ppb).…”

“…Among others, several teleostei fish species, which constitute an important part of the human diet, have been widely used to monitor marine mercury pollution (Usero et al 2003;Türkmen et al 2008;Aksu et al 2011;Mezghani-Chaari et al 2011 In Tunisia, fishing is an important income source throughout the country, where different levels of pollution occur according to each region's main economic activity (eg, industry, tourism). Therefore, monitoring Hg pollution in common edible fish species is necessary.…”

Spatial Distribution and Source Identification of Heavy Metals in Surface Waters of Three Coastal Areas of Tunisia

“…Although there have been a number of investigations on the impacts of pollutants such as hydrocarbons and nutrients (e.g., phosphate, nitrate, ammonium), total polyphenolic compounds and phosphogypsum wastes in the Sfax coast (e.g., [40,43,44]), the human and ecological risk from pollutants, namely heavy metals, have not yet been investigated in the gulf of Gabes. Indeed, the coastal zone of Sfax has been subjected to some investigations on trace metals in sediments [45] or in some seafood such as annular sea bream fish (Diplodus annularis), cow bream (Sarpa salpa), and cuttlefish (Sepia officinalis) [46], and in the marine bivalve Ruditapes decussatus [47][48], but data on the spatial distribution of dissolved trace metals in the surface seawater are scarce or absent.…”

Analysis of a population of magnetotactic bacteria of the Gulf of Gabès, Tunisia

“…The Gulf of Gabès locates in the south-eastern coast of Tunisia. It is characterized by shallow waters, important tidal activity, high temperature, and high salinity (Ladhar-Chaabouni et al 2012;Mezghani-Chaari et al 2011). This marine ecosystem is threatened by pollution from industrial activity developed along the coast.…”