Giovanni Arena

Mercury and selenium intake by seafood from the Ionian Sea: A risk evaluation

The subject of the present study is the evaluation of the concentrations of mercury (Hg) and selenium (Se) in fish and shellfish from the Gulf of Catania (Ionian Sea) and the assessment of related risk-based consumption limits per single contaminant in adults and children. In contrast to the potential harm from Hg, Se is an essential element that is normally found in high levels in seafood. If the amount of Hg is high enough, it could bind Se and irreversibly inhibit selenium-dependent enzymes. Thus, adequate levels of Se need to be available to replace the amount of Se lost to Hg sequestration, thereby maintaining normal selenoprotein synthesis. Hg analysis was conducted using a flow injection analysis system coupled with an atomic adsorption spectrometer, and Se analysis was conducted using an inductively coupled plasma mass spectrometry (ICP-MS). Of the trace elements investigated, only Hg has a limit set by the European Community for human consumption, and this was never exceeded. Nevertheless, based on Target Hazard Quotient (THQ) over 1, and on the Estimated Daily Intake per meal (EDIm) higher than the Provisional Tolerable Intake (PTI) suggested by the Joint FAO/WHO Expert Committee on Food Additive (JECFA), Hg oral exposure derived from consumption of the benthonic fish and of the bigger pelagic fish species analyzed, could follow the occurrence of systemic effects. Se was found always in molar excess respect to Hg in all pelagic fish and in the shellfish, nearly equimolar in the benthonic fish. Determining the evidence that foods, such as pelagic fish, with high molar excess of Se, could contribute to replace the amount of Se bound to Hg and thereby maintaining normal selenoprotein synthesis, is useful for a better understanding of the seafood safety.

First data on trace elements in Haliotis tuberculata (Linnaeus, 1758) from southern Italy: Safety issues.

This study evaluated for the first time the concentrations of 10 metals in wild specimens of abalone, Haliotis tuberculata (Ht) (Linnaeus, 1758) from three sites along the southern Italian coast: Gulf of Catania (CT), the Northern Coast of Messina (ME) and the harbor of Villa San Giovanni (VSG). The species is commonly found in the area and has significant commercial value. Additionally, it is long lived, thus suitable as bioindicator of the environmental monitoring. The potential human health risks due to consumption of Ht have been assessed by estimated average daily intake (EDI) and target hazard quotient (THQ) of metals, respectively. In particular arsenic (As), cadmium (Cd), copper (Cu), chromium (Cr), iron (Fe), lead (Pb), manganese (Mn), mercury (Hg), selenium (Se) and vanadium (V) were quantified in the edible tissue of specimens by acid digestion of the samples and ICP-MS determination. The highest concentrations were found in CT sample area for most metals analyzed. Mean values for Pb, Cd and Hg were lower than the maximum levels (MLs) set for bivalve mollusks by Regulation (CE) no. 1881/2006 in all sites, and average intake values below the risk levels for human consumption.

Determination of total vanadium and vanadium(V) in groundwater from Mt. Etna and estimate of daily intake of vanadium(V) through drinking water

Vanadium(V) can be found in natural waters in the form of V(IV) and V(V) species, which have different biological properties and toxicity. The purpose of this study was to determine the concentrations of total V and V(V) in groundwater from the area of Mt. Etna and to assess the estimated daily intake (EDI) of V(V) of adults and children through drinking water. Water was sampled monthly at 21 sites in 2011. Total vanadium was determined by inductively coupled plasma-mass spectrometry (ICP-MS) and speciation by ion chromatography-ICP-MS (IC-ICP-MS). The concentration of V(V) species ranged from 62.8 to 98.9% of total V, with significantly higher concentrations in samples from the S/SW slope of Mt. Etna. The annual mean concentrations of total V exceeded the Italian legal limit of 140 μg/L at four sites on the S/SW slope. In the absence of thresholds for V(V) intake, only the Environmental Protection Agency (EPA) has calculated a reference dose. Childrens EDI of V(V) at the sites with the higher V concentrations exceeded EPA thresholds (9 μg/kg/day). In particular, we found in Camporotondo, Mascalucia, Ragalna and San Pietro Clarenza sites childrens EDIs of 11, 9.3, 11 and 9.9, respectively. The EDI of V(V) was significantly higher than the literature range (0.09-0.34 μg/kg/day).