Mercury accumulation in Lethrinus nebulosus from the marine waters of the Qatar EEZ

Abstract

Total mercury (THg) and methylmercury (MeHg) were recorded in the commercial demersal fish Lethrinus nebulosus, caught from six locations in Qatar EEZ (Exclusive Economic Zone). Concentrations of THg decreased in the order: liver ˃ muscle ˃ gonad. THg concentrations in fish tissue ranged from 0.016 ppm in gonad to 0.855 ppm (mg kg−1 w/w) in liver tissues, while concentrations in muscle tissue ranged from 0.24 to 0.49 ppm (mg kg−1 w/w) among sampling sites. MeHg concentrations were used to validate food web transfer rate calculations. Intake rates were calculated to assess the potential health impact of the fish consumption. There is no major threat to human health from the presence of Hg in L. nebulosus, based upon reasonable consumption patterns, limited to no more than three meals of L. nebulosus per week.

Health risk assessment of methyl mercury from fish consumption in a sample of adult Qatari residents

“…Moreover, HM had the highest T-Hg concentrations. This finding is in agreement with previous studies where T-Hg concentrations in HM were found to be the highest and exceeded the guidelines levels in some samples (Elsayed et al, 2020;Al-Ansari et al, 2017;Laird et al, 2017;Ahmad et al, 2016;Burger et al, 2014). HM is a carnivorous predatory fish species that is placed at the top level of the trophic chain (Wei et al, 2018).…”

“…These variations may be related to the sampled fish (species, age, and size), sampling sites, and season (Da Silva et al, 2020;Elsayed et al, 2020, Wei et al, 2018. Nevertheless, previous studies conducted in the Gulf region reported similar results (Elsayed et al, 2020;Al-Ansari, 2017;Laird et al, 2017;Ahmad et al, 2016;Burger et al, 2014). All of the commercially available fish species in Qatar are considered to have T-Hg levels within acceptable levels set by EU.…”

“…In Qatar, fish constitutes a major food comodity (Canada, 2021). Moreover, there are limited data on the concentrations of mercury in fish and seafood available in Qatar (Elsayed et al, 2020;Al-Ansari, 2017). Previous studies focused on determining mercury contamination levels in limited marine fish species at different trophic levels that were collected from local sites.…”

The concentration and biomagnification of trace metals and metalloids across four trophic levels in a marine food web

“…There are numerous physiological and ecological factors that might affect metal contamination and bioaccumulation in the marine environment: geographic location (Frodello and Marchand, 2001;Lewis and Devereux, 2009;Xia et al, 2019;Jarosz-Krzemińska et al, 2020;Lawson et al, 2021), feeding patterns (Azevedo et al, 2020), age and size of species (Mustafa and Guluzar, 2003;Farkas et al, 2003;Le Bourg et al, 2019), sex (Gewurtz et al, 2011;Jankovská et al, 2013), tissue type (Bilandžic et al, 2012;Al-Ansari et al, 2017) and metabolic rates (Caurant et al, 1996;Seco et al, 2021).…”

Methylmercury, Trace Metals, Organotins and Their Effects on the Qatari Mangrove Shrimp, Palaemon khori

“…In the Arabian Gulf, values of MeHg ranging from 0.112 to 0.865 mg/kg have been reported in tissues of various crustacean species in different locations [19], sometimes exceeding the maximum recommended level of 0.5 mg/kg wet weight [20]. In Qatar, concentrations of MeHg in local commercial fish species, such as Lethrinus nebulosus, were found to range from 0.064 to 0.871 mg/kg [21]. Methylmercury may complex with other chemical groups within the cells leading to DNA damage through free radical formation [22] and also produce chromosomal aberrations [23]: it has indeed been previously recognized as a genotoxic contaminant in aquatic organisms (e.g., [24]).…”