Roberto Miniero

An overview of TCDD half-life in mammals and its correlation to body weight.

Major determinants of TCDD half-life in organisms are lipophilicity, metabolism, and hepatic binding sites. In addition, half-life seems to be empirically correlated to organism body weight. In this paper, this correlation is evaluated by a regression analysis of half-life measures and body weight data selected from the literature. Single exposure studies on laboratory mammals and human half-life data were specifically taken in consideration. The analysis outcome appears to be highly significant probably owing to the stability and generally slow metabolism of the substance in the organisms considered. The effect on half-life of factors other than body weight does not seem to influence significantly data dispersion around the regression line. The potential effects of a dose-dependent excretion cannot be excluded as toxicokinetic studies have been usually carried out at high exposure doses.

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.

Polychlorinated dibenzodioxins, dibenzofurans, and biphenyls in fresh water fish from Campania Region, southern Italy

Twenty-eight fish muscle specimens from the main water bodies of the Campania Region were analyzed in our laboratory. On average, results showed a low contamination by PCDDs+PCDFs and a relatively more important presence of DL-PCBs. All specimens were compliant with EU regulatory maximum levels. Cumulative PCDD+PCDF+DL-PCB concentrations (TEQ(TOT)) were comprised in the range 0.223-11.4 pgWHO(97)-TEQ g(-1) fresh weight (fw). DL-PCB contribution to TEQ(TOT) was on average greater than 86% (range, 50.2-97.1%). The cumulative concentrations of 30 non-dioxin-like PCB congeners (Σ(30)(NDL-PCBs)) and of the six indicators (Σ(6)(NDL-PCBs)) were respectively in the ranges 3.30-515 and 1.30-195 ng g(-1) fw. The hybrid clustering approach adopted to analyze the sample-specific congener profiles indentified the main analytical patterns present in the database and, in particular, two main diverse exposure macro-areas that seem to exist north and south of the city of Naples. The distribution of PCDD and PCDF congeners among different species showed significant variations from chub (Leuciscus cephalus), characterized by a higher proportion of low-chlorinated congeners (e.g. 2,3,7,8-T(4)CDD), to eel (Anguilla anguilla), whose contamination consisted mainly of highly chlorinated congeners (e.g. O(8)CDD). To have a more complete perspective in relation to the contaminants present in the environment, the study suggestion is to use benthic as well as pelagic species to obtain an integrated characterization of fish tissue contamination.

Mercury (Hg) and methyl mercury (MeHg) concentrations in fish from the coastal lagoon of Orbetello, central Italy

Total mercury (Hg tot) and methyl mercury (MeHg) were quantified in several specimens of Dicentrarchus labrax and Sparus aurata from the east basin of the Orbetello lagoon, central Italy. The size of each specimen was recorded to estimate body burdens (BBs); =Hg tot and MeHg were measured in fillets of both species. Hg tot and MeHg in S. aurata ranged between 0.355-1.58 and 0.341-1.53 μg/g wet weight (ww), respectively; in D. labrax, their ranges were 0.284-2.54 and 0.214-2.35 μg/g ww. Approximately 90% of the concentrations measured exceeded Hg tot regulatory maximum level of 0.5 μg/g ww; however, exceedance rate was different in the two species studied. No correlations between specimen size and Hg tot or MeHg BBs were detected in this study.

Polychlorodibenzodioxin and -furan (PCDD and PCDF) and dioxin-like polychlorobiphenyl (DL-PCB) congener levels in milk of grazing sheep as indicators of the environmental quality of rural areas.

An observational study was set up to evaluate how the quality of the environment may influence the levels of of PCDDs, PCDFs, and DL-PCBs in sheeps milk. Seven farms under natural and anthropogenic pressures were considered, along with an inventory of the surrounding regular and natural sources of emissions. Analysis by HRGC-HRMS revealed the highest cumulative levels (2.1 pg of WHO(1998)-TE/g fat) in one organic and one conventional farm, each close to a relevant bushfire. Their pattern was characterized by a noticeable contribution (24%) from mono-ortho-PCB congeners to the cumulative WHO-TE. For the other farms, close to potential anthropogenic sources, the levels recorded in milk ranged from 0.7 to 1.3 pg of WHO-TE/g fat. The health and reproductive indicators were in all herds within the physiological range. Results suggest the environmental quality in extensive farming system should be eligible as a food safety factor, also for organic productions.

Determination of the composition of complex chemical mixtures in the soil of an industrial site

Abstract Since the late 1800s, the ACNA chemical plant at Cengio (Savona, northern Italy) has used a large portion of the 55 ha of land that it owns to dispose of its chemical wastes and refuse materials by dumping and burying them in the earth. As a result of this practice, an extent of ground of well over 106 m3 and up to 20 m thick has become highly contaminated. In addition, due to the local hydrogeological conditions, for years the site has been a contamination source for the nearby Bormida River and the territory downstream. Since satisfactory primary knowledge of the quality and quantity of the soil contamination of the site was not available, a pilot study was financed to provide the information required. In this paper, the analytical approach to and procedure for the multianalyte multilaboratory assessment in complex soil and sediment matrices are described. The analyte group includes nine families of chemicals which exhibit highly variable toxic potentials, water solubilities, and kows (lg[kow] approximately between 2 and 12). A preliminary appraisal of the procedure is presented with specific reference to the detection of polychlorinated dibenzodioxins, dibenzofurans, and biphenyls of the first 43 subsoil and sediment samples from the site. Also, a comparison is made to the Seveso/ICMESA accident of July 1976.

Chemometric data analysis application to Sparus aurata samples from two offshore farming plants along the Apulian (Italy) coastline.

The levels of polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs), dioxin-like polychlorobiphenyls (DL-PCBs), non-dioxin-like polychlorobiphenyls (NDL-PCBs), and polybromodiphenyl ethers (PBDEs) in fish collected from two marine offshore farming plants were determined. Each sample was constituted by specimens of the same size collected at the same time in four different seasons along the farming year. The feeds given were of industrial origin and the plants were positioned in two different sites respectively exposed to different environmental characteristics. A chemometric approach was applied to interpret the subtle differences observed in fish body burdens across the three chemical groups taken into consideration. The approach consisted in a stepwise multivariate process including a hierarchical cluster analysis (CA) and a linear discriminant analysis (DA). The two main clusters determined by CA were subjected to the canonical DA, backward and forward selection procedures to select the best discriminative functions. A clear temporal and spatial discrimination was found among the samples. Across the three chemical groups, the monthly separation seemed to depend on the growth process and the main exposure was due to the feed. In addition, the two plants differed significantly from the environmental point of view and the most important discriminating group of chemicals were the NDL-PCBs. The approach resulted really effective in discriminating the subtle differences and in individuating suggestions to improve the quality of culturing conditions.

Persistent organic pollutants (POPs) in fish collected from the urban tract of the river Tiber in Rome (Italy)

European eel and chub samples were analyzed to determine the levels of non-dioxin-like polychlorobiphenyls (NDL-PCBs), polychlorodibenzodioxins (PCDDs) and polychlorodibenzofurans (PCDFs), dioxin-like PCBs (DL-PCBs), and brominated polybromodiphenyl ethers (PBDEs) in order to evaluate the extent of contamination of the river Tiber along the urban tract through the city of Rome (Italy). All samples presented detectable levels of the chemicals analyzed, and exhibited species-specific differences in terms of congener composition and total concentrations. On average the European eel presented the highest values. In this species the dioxin-like compound sums (WHO-TEQs) exceeded the pertinent maximum levels (MLs). Non-ortho PCBs constituted approximately 80% of WHO-TEQ toxicological potential whereas NDL-PCB and PBDE concentrations appeared to match values determined in other polluted aquatic ecosystems where non-point contamination sources were present. The contamination patterns determined in fish tissues seemed to reflect the impact of generic contamination source(s).

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.

Polychlorinated biphenyl, dibenzodioxin, and dibenzofuran occurrence in the general environment in Italy

Abstract Topsoil and sediment samples from the Italian general environment were assayed for PCBs, PCDDs, and PCDFs. PCB levels appear to range between 6.2 × 102 and 1.6 × 104 ng/kg in open areas and between 1.2 × 102 and 6.8 × 102 ng/kg in cave samples. PCDD plus PCDF levels, as TCDD equivalents (TE units), are between 1.0 × 10−1 and 4.3 ngTE/kg in open areas, and between 5.7 × 10−2 and 1.2 × 10−1 ngTE/kg in cave samples. The less chlorinated PCB homologs seem to reach higher relative levels in cave sediments than in the topsoil of open areas, this probably due to a lower dissipation rate. PCDD plus PCDF levels (TE units) versus cumulative PCB levels provide highly significant linear regression in logarithmic coordinates.