Two-year study of lipophilic marine toxin profile in mussels of the North-central Adriatic Sea: First report of azaspiracids in Mediterranean seafood.

Since the late 1980s, the North-central Adriatic Sea has frequently experienced blooms of harmful algal species, producing marine lipophilic toxins (MLTs) which accumulate in mussels and pose a serious threat to consumer health. Here, we present a 2-year LC-MS/MS study (2012-2014) of the MLT profile in mussels from the North-central Adriatic Sea in the context of the presence of toxic phytoplankton concentrations in seawater. Okadaic acid increased in mussels from all areas during the summer and autumn-winter periods with a rising trend between 2012 and 2014. In the same periods, Dinophysis sp. increased in abundance in seawater, but the highest densities of algae did not always coincide with the highest levels of toxins in mussels. Yessotoxins (YTXs) content in mussel increased sharply in the autumn-winter periods even exceeding the legal limit; although this accumulation did not always correlated with the YTX-producers in water (such as Lingulodinium polyedrum and Protoceratium reticulatum) a massive bloom of Gonyaulax spinifera was reported in November 2013, suggesting the role of this species in YTXs shellfish contamination. Traces of Azaspiracid 2 (AZA-2) were observed often in mussels during the study period, confirming for the first time the presence of this biotoxin in Mediterranean seafood.

Arsenic Speciation in Fish Products and Seafood as a Prerequisite for Proper Risk Assessment.

The Boi Cerbus lagoon, facing a mining and industrial site in Sardinia (Italy), is an important fishing area for the local population. Previous studies showed high concentrations of total arsenic (Astot) in fish, molluscs and crustaceans sampled in the lagoon, and a possible exceeding of the provisional tolerable weekly intake set by the Joint FAO/WHO Expert Committee on Food Additives by some local consumer groups. However, the percentage of inorganic As (Asinorg) should be known for a correct assessment of potential risk, as its toxicity is much higher than that of the organic forms. Eighty samples of 14 different species of fish, molluscs and crustaceans, sampled in the Boi Cerbus lagoon in 3 different seasons (winter, spring and summer), were analysed for Astot by inductively coupled plasma mass spectrometry (ICP-MS) and Asinorg by high performance liquid chromatography-ICP-MS. All the data obtained from the analysis were statistically processed to evaluate significant differences based on season, taxon and habitat, in preparation for a subsequent risk assessment.

Individual methylmercury intake estimates from local seafood of the Mediterranean Sea, in Italy.

A Seafood Frequency Questionnaire (SFQ) broken down in more than 42 items with 8-week coverage was interview-administered to 278 adults aged 19-82years (167 women, 98 in the reproductive age 19-45years, and 111 men), resident on the Italian Mediterranean shore and frequent buyer at local fish markets. Methylmercury (MeHg) intake on individual basis was estimated for a selected occurrence equal to the median value+Median Absolute Deviation (MAD) in each seafood species reported (conservative scenario). MeHg occurrence was derived from an extensive seafood database referred to years 2009-2011. Accounting for an average body weight of 62.2kg, 24.6% of women resulted overexposed with respect to the European Food Safety Authority (EFSA) Tolerable Weekly Intake (TWI) for MeHg of 1.3µg/kg bw, with a mean of 0.92µg/kg bw. In the vulnerable group aged 19-45years, 29.6% exceeded the TWI. Rather than the amount of seafood consumed, the seafood choice appears to be the main determinant of the MeHg intake. Risk awareness was reported in the 49% of SFQs. Uncertainties related to such estimates from questionnaires are discussed, in order to give adequate health recommendations without compromising seafood consumption in the Mediterranean region.

Dietary exposure to trace elements and radionuclides: the methodology of the Italian Total Diet Study 2012-2014.

This article presents the methodology of the Italian Total Diet Study 2012-2014 aimed at assessing the dietary exposure of the general Italian population to selected nonessential trace elements (Al, inorganic As, Cd, Pb, methyl-Hg, inorganic Hg, U) and radionuclides (40K, 134Cs, 137Cs, 90Sr). The establishment of the TDS food list, the design of the sampling plan, and details about the collection of food samples, their standardized culinary treatment, pooling into analytical samples and subsequent sample treatment are described. Analytical techniques and quality assurance are discussed, with emphasis on the need for speciation data and for minimizing the percentage of left-censored data so as to reduce uncertainties in exposure assessment. Finally the methodology for estimating the exposure of the general population and of population subgroups according to age (children, teenagers, adults, and the elderly) and gender, both at the national level and for each of the four main geographical areas of Italy, is presented.

Mercury occurrence in Italian seafood from the Mediterranean Sea and possible intake scenarios of the Italian coastal population.

Mercury (Hg) settlements in the Mediterranean Sea determine a potential toxicological relevance of seafood intakes for coastal populations. To assess this possibility, fish, molluscs, and crustaceans of commercial size of 69 different species were sampled and analyzed for total mercury (Hg(TOT)) from georeferenced areas and evaluated for their compliance with the European Union Maximum Residue Limits of 0.5 and 1.0 mg/kg wet weight (ww). Accounting for the weekly estimated seafood intake in the Italian coastal population (mean 469-626 g/person/week) it was then possible to recover threshold contamination values in seafood. Under a Tolerable Weekly Intake of 1.3 µg/kg/bw/week, a threshold seafood contamination <0.10 mg/kg ww has been derived for sensitive groups. A suitable algorithm based on the parallel MeHg and Hg(TOT) analysis on the most consumed species, helped to refine the uncertainties related to the conservative assumption in seafood all the Hg(TOT) present is in form of MeHg. This work aims to improve the link between the risk management and risk assessment strategies, with the identification of those fish and seafood species, that, when regularly consumed, could determine or prevent potential Hg(TOT)/MeHg overintakes in sensitive groups.