Drivers of the accumulation of mercury and organochlorine pollutants in Mediterranean lean fish and dietary significance

Abstract

An integrated assessment of lean fish of commercial value as Hg and organochlorine compound source into the population of the Balearic Islands were reported. Dependences between pollutant concentrations, trophic level, fish species, specimen weight and physical-chemical properties were evaluated. Hg and total DDTs showed highest variability between fish species whereas PCBs and HCB displayed more constant median values. The organochlorine compounds found in highest concentrations were those with highest hydrophobicity, consistently with their higher bioaccumulation potential. These pollutant concentrations were higher in Mediterranean than Atlantic fish. Higher median total DDT and PCBs concentrations were also observed in the third than the second trophic level species. The observed concentrations were below the threshold recommended by the EU for human consumption (75ng/g wet weight). The Hg concentrations were higher in Mediterranean than Atlantic fish, with average values of 1.5μg/g ww and 0.43μg/g ww, respectively. Forty-one percent of the specimens from the Mediterranean and 25% of dusky grouper specimens from the Atlantic Ocean showed Hg concentrations above the EU recommended limits for human consumption, either 0.5μg/g ww or 1μg/g ww. In the third trophic level, a significant dependence between median Hg concentrations and weight of each studied species was observed, which remained significant in specimen weight correlations. Independent species correlations of Hg concentrations vs individual weight generally showed higher concentrations at higher weight. Weight/size of the individuals was therefore an important factor for Hg accumulation but the trend was modulated by a species effect. Extrapolation of the observed Hg concentrations in Mediterranean fish to Provisional Tolerable Weekly Intakes (PTWIs) showed higher intakes than the thresholds recommended by EFSA for adults and children, 110% and 140%, respectively. The estimated PTWIs for MeHg corresponded to 310% and 400% of the recommended threshold values. The PTWI values for organochlorine compounds were lower than those recommended.

Changes of organochlorine compound concentrations in maternal serum during pregnancy and comparison to serum cord blood composition

“…Structural confirmations were performed by GC coupled to mass spectrometry (MS, Agilent Technologies 5975 C, Agilent Palo Alto, USA) operating in negative chemical ionization mode (GC-NICI-MS; Junqué et al, 2018).…”

“…Despite these results only concern a few significant cases, they consistently show that the most affluent women with highest education level are those more exposed to some of these OCs. This higher exposure could respond to distinct dietary habits (Tarasuk et al, 2010) since these groups tend to have a higher proportion of fish and seafood in the diet and fish has been shown to be a preferred source of incorporation of these pollutants in Mediterranean cohorts (Junqué et al, 2018). However, in the specific case of Tarragona, examination of the food consumption habits did not show any significant trend in relation to OC incorporation except for the positive association of organic food consumption and the concentration of PCB138 in the maternal serum collected in the first trimester and at delivery.…”

“…This class of compounds include polychlorobiphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and its metabolites, hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB) and others. Their lipophilic nature and high chemical stability lead to their bioaccumulation in food chains and the human body (Junqué et al, 2017(Junqué et al, , 2018Bravo et al, 2019). Due to their adverse effects in humans and the environment, their use was progressively banned in many countries since the 1970s and they were finally banned globally, with a few exceptions, by the Stockholm Convention in 2001 (Stockholm Convention, 2005).…”

Biomonitoring of pesticides, pharmaceuticals and illicit drugs in a freshwater invertebrate to estimate toxic or effect pressure

“…Additionally, neonicotinoid insecticides, which are largely used on land and have rarely been targeted for measurement in aquatic fauna except for a small number of recent studies in fish and invertebrates (Munz et al, 2018; Jabeen et al, 2015; Masiá et al, 2013). However, other pesticides have been more routinely monitored in aquatic biota, such as organochlorine insecticides, which are reported at the low to mid ng g −1 range in both vertebrates and invertebrates (Varol and Sünbül, 2017; Junqué et al, 2018). This is likely due to extensive regulation of these types of contaminants following seminal research in the 1950s (e.g., with dichlorodiphenyltrichloroethane (DDT) (Carson, 2002)) to the more recent Stockholm Convention treaty on persistent organic pollutants which cover many other such compounds (Commission, E., 2004).…”

Determinants of Persistent Organic Pollutants (POPs) Levels in Human Specimens: A Review

“…A study from Spain discovered associations between fish, fruit, meat, vegetables, and shellfish consumption and organochlorine compounds levels in serum (71). Fish and meat consumption significantly correlated with DDT levels, but the most significant food items that affected organochlorine compounds levels in the serum were fish and fruit.…”