Elena Dellatte

Assessment of the dietary exposure to non-dioxin-like PCBs of the Italian general population

The dietary intake of non-dioxin-like polychlorinated biphenyls (NDL-PCBs) has been estimated using the sum of six indicator PCBs (Sigma(6)(PCBs)) in the Italian general population. Data from a national food consumption survey were combined with the mean concentration values of the individual six indicator PCBs (IUPAC Nos. 28, 52, 101, 138, 153, and 180) in foodstuffs available on the European market. Mean concentrations were estimated from the raw data set provided by the European Commission (DG SANCO). The purpose was to describe the distribution of NDL-PCB dietary intake in the Italian population, and to investigate to what extent the variability in dietary habits may cause higher exposures to the aforesaid contaminants. Results indicated a mean dietary intake of Sigma(6)(PCBs) corresponding to 24.6, 16.1, and 10.9 ng kg-bw(-1) day(-1) for toddlers (0.5-6 years old, excluding breastfeeding), children (7-12 year old), and adults (13-94 years old), respectively. Fish and fishery products and milk and dairy products were the major contributors to the total dietary intake. The highest exposures due to variation in dietary habits were in general two-three times higher than the corresponding mean values and they were generally due to a higher fish consumption rate. The NDL-PCB dietary intake decreased with age until about 10-12 years; afterwards it appeared to remain constant. The tolerable daily intake (TDI) has not been established for these contaminants; however, action and maximum allowed levels in feeding stuffs and food recently established by the European Commission for dioxin-like PCBs could also protect consumers from exposure to NDL-PCBs.

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.

Dietary exposure to selected perfluoroalkyl acids (PFAAs) in four European regions

The dietary exposure to selected PFAAs was estimated in four selected European states (Belgium, the Czech Republic, Italy and Norway) representing Western, Southern, Eastern and Northern Europe. The harmonised sampling programme designed in the European Union project PERFOOD was targeted at identifying seven selected PFAAs, including perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), in food items that are most important both in terms of consumption and based on known high contamination patterns. The estimated average dietary exposure for adults (18–64 years) and children (3–9 years) is generally below or close to 1 ng kg–1 BW day–1 for all seven PFAAs. Considering the high consumption of food groups that contribute most to the exposure does not result in estimates exceeding 4 ng kg–1 BW day–1. Thus, based on the TDIs proposed by EFSA for PFOS (150 ng kg–1 BW day–1) and PFOA (1500 ng kg–1 BW day–1), no concern can be identified. There are distinct dietary exposure patterns from region to region as a result of different food consumption and contamination patterns. Foods of plant origin (e.g. fruit and vegetables) are most important for the dietary exposure to PFHxA, PFOA and PFHxS, while the consumption of foods of animal origin (particularly fish and seafood) mostly contributes to the dietary exposure to PFDA and PFUnDA. For the dietary exposure to PFNA and PFOS, food of animal and plant origin contributes with equal importance. In conclusion, region-to-region differences as well as the relative importance of food of different origin for each PFAA should be paid more attention in further research.

Occurrence of selected perfluorinated alkyl acids in lunch meals served at school canteens in Italy and their relevance for children’s intake

Ready-to-eat servings may be more contaminated with perfluorinated alkyl acids (PFAAs) than the corresponding unprocessed foods due to the presence of PFAAs in and transfer from food contact materials (FCM) and cookware. Therefore, the presence of selected PFAAs in meals served weekly at lunch time in six Italian school canteens was assessed. Five towns were selected representing different areas with local water and food supply. Daily lunch menus were sampled and pooled to form a composite. Analyses were carried out on the weekly composite from each canteen. UPLC-MS/MS quantification limits were in the 6.0–12 pg g–1 range for the selected PFAAs (PFHxA, PFOA, PFNA, PFDA, PFUnDA, PFHxS, branched and non-branched PFOS). Non-branched PFOS was quantified in four out of six composites, with levels ranging from 14 to 25 pg g–1, while PFOA and PFDA were determined in two out of six in the range 6.5–8.2 pg g–1. Theoretical estimates and analytical results in the same order of magnitude indicate a negligible contribution from food processing and serving to meal contamination. When composite analytical data are transposed into dietary estimates, it is shown that Italian school-age children have intakes in the range of 0.3–1.1 and 0.5–1.4 ng kg–1 bw day–1 for PFOA and PFOS respectively, well below the corresponding tolerable daily intakes (TDIs).

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.

Exposure to polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (DL-PCBs) and polybrominated diphenyl ethers (PBDEs) through the consumption of prepared meals in Italy.

Diet is a relevant source of exposure to environmental pollutants. Dietary intake of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (DL-PCBs) and polybrominated diphenyl ethers (PBDEs) by the Italian population was assessed through a duplicate diet study on prepared meals. Baby food composite representative of the diet of toddlers aged 9–12 months and school canteen servings from four towns in Italy representing the diet of children aged 4–9 years were collected on a 5-day basis. Similarly, 5-day lunches from an office canteen, 7-day lunches from a hotel-school, three fast food meals, and eight duplicate 1-day meals of individuals (one vegetarian) were selected to represent the diet of adults aged above 18 years. Servings from each diet were then pooled to form a composite and analysed. Dietary intake was estimated from the resulting contaminant levels in composites combined with age-related food consumption data from national survey. The mean upper bound (UB) intakes for cumulative PCDDs, PCDFs, and DL-PCBs were 0.67, 0.63–0.92, and 0.27–0.63 pg WHO2005-TE kg−1 body weight (bw) day−1 for toddlers, children and adults, respectively. BDE-47 (UB) ng kg−1 bw day−1 estimates were 2.75 in toddlers, 0.08–0.16 in children and 0.03–0.09 in adults. Similarly, for BDE-99 higher UB intakes (ng kg−1 bw day−1) resulted in toddlers (1.26), than those in children (0.06–0.08) and adults (0.03–0.10), respectively. The above estimates fall below the tolerable weekly intake (TWI) (14 WHO2005-TE kg−1 bw day−1) established by the European Union Scientific Committee on Food (SCF) for PCDD/Fs and DL-PCBs. The margin of exposure (MOE = 3) of toddlers to BDE-99 clearly indicates this age group as target for a risk-oriented approach. This study is proposed as a first cost-effective screening in PCDD, PCDF, DL-PCB and PBDE intake assessment, with a focus also on time trends. Graphical Abstract

Biomonitoring of perfluorinated compounds in adults exposed to contaminated drinking water in the Veneto Region, Italy

In 2013 a contamination of drinking water by perfluoroalkylated substances (PFASs) was discovered in areas of the Veneto Region (northern Italy). In this study the exposure to PFASs of people living in the aforesaid areas was characterized: contaminant serum concentrations were measured and compared with those of a control population group living in neighboring areas at background exposure (based on available drinking water data). The enrolled population was also genotyped for the OATP1A2*3 allelic variant, possibly affecting PFAS excretion and hence the internal dose. The difference in PFAS concentrations between exposed and not exposed subjects was significantly larger for nine of the 12 substances analyzed, and confirmed that water contamination had resulted in an appreciable high exposure of the residing population over time. Within the group of exposed subjects, subgroups at different exposure levels were identified. The contamination of drinking water of the residence area was found to be the main factor influencing PFAS serum levels; in addition to water contamination, other relevant influencing factors were sex, the years of residence and raising own livestock. No relationship with the genetic trait for the studied renal transporter was evidenced. These results provide a baseline characterization of PFAS exposure of the monitored population groups for further studies, planned to be carried out in the near future.