Stefania Paola De Filippis

Correlates of oxidative stress in wild kestrel nestlings (Falco tinnunculus)

The fitness of an organism can be affected by conditions experienced during early development. In light of the impact that oxidative stress can have on the health and ageing of a bird species, this study evaluated factors accounting for the variation in oxidative stress levels in nestlings of the Eurasian kestrel (Falco tinnunculus) by measuring the serum concentration of reactive oxygen metabolites and the serum antioxidant barrier against hypochlorite-induced oxidation. The ratio between these two variables was considered as an index of oxidative stress, with higher values meaning higher oxidative damage. Six-chick broods showed the highest level of oxidative stress, while no effect of sex was found. Age showed an inverse relationship with the oxidants and the levels of oxidative stress, with younger birds having higher levels. Hatching date, body condition, body mass and carotenoid concentration did not show any relationship with oxidants, antioxidants or degree of oxidative stress. These findings suggest that intrabrood sibling competition could play a role in determining oxidative stress, and that in carnivorous birds other antioxidant molecules could be more important than carotenoids to reduce oxidative stress.

Hormetic effect(s) of tetracyclines as environmental contaminant on Zea mays.

Animal wastes from intensive pig farming as fertilizers may expose crops to antimicrobials. Zea mays cultivations were carried out on a virgin field, subjected to dressing with pig slurries contaminated at 15 mg L(-1) of Oxy- and 5 mg L(-1) of Chlor-tetracycline, and at 8 mg L(-1) of Oxy and 3 mg L(-1) of Chlor, respectively. Pot cultivation was performed outdoor (Oxy in the range 62.5-1000 ng g(-1) dry soil) and plants harvested after 45 days. Tetracyclines analyses on soils and on field plants (roots, stalks, and leaves) did not determine the appreciable presence of tetracyclines. Residues were found in the 45-day pot corn only, in the range of 1-50 ng g(-1) for Oxy in roots, accounting for a 5% carry-over rate, on average. Although no detectable residues in plants from on land cultivations, both experimental batches showed the same biphasic growth form corresponding to a dose/response hormetic curve.

Perfluorinated alkylated substances in vegetables collected in four European countries; occurrence and human exposure estimations

The human diet is recognised as one possible major exposure route to the overall perfluorinated alkylated substances (PFAS) burden of the human population, resulting directly from contamination of dietary food items, as well as migration of PFAS from food packaging or cookware. Most European countries carry out national monitoring programs (food basket studies) to monitor contamination with pollutants. Usually, for PFASs, non-coordinated approaches are used in Europe, since food basket studies are mainly carried out by national authorities following national requirements and questions, making comparisons between different countries difficult. A harmonised sampling campaign collecting similar food items in a uniform procedure enabling direct comparison between different regions in Europe was designed. We selected four countries (Belgium, Czech Republic, Italy and Norway), representing the four regions of Europe: West, East, South and North. In spring 2010 and 2011, 20 different types of vegetables were sampled in Belgium, Czech Republic, Italy and Norway. Perfluorinated carboxylic acids (PFCAs) were the main group of detected PFASs, with perfluorinated octanoic acid (PFOA) as the most abundant PFCA (with exception of samples from Czech Republic), followed by perfluorinated hexanoic acid and perfluorinated nonanoic acid. Dietary intake estimates for PFOA show only low human exposure due to vegetable consumption for adults and children, mostly governed by high intake of potatoes.

Temporal and Spatial Covariation of Gender and Oxidative Stress in the Galápagos Land Iguana Conolophus subcristatus

Physiological responses to organismal stress can have direct impacts on individual fitness. While responses to stressors mediated by glucocorticoid hormones are well studied, the regulation of the redox system via pro‐oxidant and antioxidant balance as well as the natural causes of oxidative stress in nature remain poorly known, especially for reptiles. In this study, we investigate the interpopulation and intersex variation in oxidative damage and plasma antioxidant capacity in the Galápagos land iguana, Conolophus subcristatus, over a 3‐yr study to evaluate what factors (e.g., season, food availability, reproductive activity) can explain levels and patterns of oxidative damage and of plasma antioxidant capacity. Our results indicate that (1) males showed lower levels of oxidative damage, higher levels of plasma antioxidant capacity, and better body condition than females and (2) significant interactions exist among patterns of oxidative damage across sexes, sampling localities, body condition, and season. These results suggest that reproductive activity and food abundance might act as determinants shaping levels and patterns of oxidative stress of land iguanas.

Occurrence of perfluorinated alkylated substances in cereals, salt, sweets and fruit items collected in four European countries

In the context of a European project, 12 perfluoroalkyl acids (PFAAs) were determined in 14 food items collected in four European countries representing northern, southern, eastern and western Europe. This study presents the results of PFAAs measured in fruit, cereals, sweets and salt. Out of the 12 PFAAs, 10 PFAAs were detected in 67% of the samples. Overall, PFOA was the most abundant compound and the highest concentrations were found for PFOS but all were less than 1ngg(-1). When comparing the four countries, highest levels and detection frequencies were observed in Belgium (Western Europe), followed by the Czech Republic (Eastern Europe), Italy (Southern Europe) and finally Norway (Northern Europe). Comparison of profiles and levels is difficult due to variations in constitution of the food categories in the investigated countries and countries of origin of the food items. Dietary intake assessments for PFOS and PFOA show that the daily intake of PFAAs is far below the existing tolerable levels. However, they contribute to the total dietary intake and should therefore be included in future dietary exposure assessments.

Bioaccumulation of Dioxin-like Substances and Selected Brominated Flame Retardant Congeners in the Fat and Livers of Black Pigs Farmed within the Nebrodi Regional Park of Sicily

An observational study was designed to assess the bioaccumulation of polychlorodibenzodioxins (PCDD) and polychlorodibenzofurans (PCDF), dioxin-like polychlorobiphenyls (DL-PCB), and 13 selected polybromodiphenylethers (PBDE) in autochthonous pigs reared in the Nebrodi Park of Sicily (Italy). Perirenal fat and liver samples were drawn from animals representative of three different outdoor farming systems and from wild pigs and then analyzed for the chemicals mentioned previously. The highest concentrations of PCDD + PCDF and DL-PCB were detected in the fat (0.45 and 0.35 pg World Health Organization toxicity equivalents [WHO-TE] per g of fat base [FB], respectively) and livers (12.7 and 3.28 pg WHO-TE per g FB) of the wild group, whereas the free-ranging group showed the lowest levels (0.05 and 0.03 pg WHO-TE per g FB in fat and 0.78 and 0.27 pg WHO-TE per g FB in livers). The sum of PBDE congeners was highest in wild pigs (0.52 ng/g FB in fat and 5.64 ng/g FB in livers) and lowest in the farmed group (0.14 ng/g FB in fat and 0.28 ng/g FB in livers). The contamination levels in fat and livers of outdoor pigs had mean concentration values lower than those levels reported for intensively indoor-farmed animals. In wild pigs, bioaccumulation was associated with their free grazing in areas characterized by bush fires. The results of this study aid to emphasize the quality of the environment as a factor to guarantee food safety in typical processed pig meat products, specifically from outdoor and extensive Nebrodi farming systems.

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.

Pentachlorophenol, polychlorodibenzodioxin and polychlorodibenzofuran in eggs from hens exposed to contaminated wood shavings

Laying hens may be exposed to pentachlorophenol (PCP) present in bedding materials derived from treated timber. As a result, this chemical and its contaminants or degradation products, such as polychlorodibenzodioxins (PCDDs) and polychlorodibenzofurans (PCDFs), may be present in eggs. The litter-to-eggs transfer and depletion of these compounds were studied in a flock of laying hens reared on contaminated wood shavings. PCP determination was carried out via high resolution gas chromatography coupled to low resolution mass spectrometry/mass spectrometry (HRGC–LRMS/MS); PCDDs and PCDFs were quantified by HRGC–HRMS (SIM). After substitution of the litter contaminated with PCDDs and PCDFs at an average of 50 pg WHO-TE g−1 and with PCP at 15 µg g−1, pooled eggs from six selected hens were sampled twice a month for the depletion study. At steady state, PCDDs and PCDFs showed a transfer ratio of 0.9; for PCP it was 0.03. PCP concentration in eggs (500 ng g−1 whole weight) fell sharply the second week after exposure withdrawal; for PCDDs and PCDFs (47 pg WHO-TE g−1 fat, at day 0), the overall TEQ half-life was estimated at an average of 3.8 weeks. Due to differences in toxicokinetics (a faster depletion), PCP does not appear to be a suitable marker of PCDD and PCDF violative levels. However, the prominent analytical contribution of H7CCD and O8CCD in the contamination profile may help to trace the source of contamination. Among congeners, 2,3,7,8 T4CDF exhibited a different depletion pattern, indicating a possible mechanism of active transport.

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

Modeling of DR CALUX® bioassay response to screen PCDDs, PCDFs, and dioxin-like PCBs in farm milk from dairy herds

A recent issue in the EU legislation is the evaluation of the toxicologically-equivalent contribution of dioxin-like polychlorobiphenyls (DL-PCBs) in addition to that coming from polychlorodibenzodioxins (PCDDs) and polychlorodibenzofurans (PCDFs) as contaminants in foods for a total of 29 congeners. This fact is determining the need to revise analytical criteria both for confirmatory and screening analysis. In this work, a modeling was developed to check the reliability of the outcomes of the DR CALUX bioassay when applied to farm milk samples characterized by large differences in congener patterns. To reproduce some field conditions where DL-PCB contributions up to 90% of total WHO-TEQs (HRGC-HRMS assessment) were recorded in dairy products, goat milk samples from a common bulk were fortified at different TEQ levels with mixtures containing either PCDDs and PCDFs or non-ortho substituted DL-PCBs. Fortification ranged approximately 4.5-15 pgWHO-TEQ/g fat. Based on the results, DR CALUX relative potency value (REP) of DL-PCB 126 was estimated 0.061 against the canonical WHO-TEF of 0.1. The value of 0.061 together with the other DR CALUX REPs from the literature for the remaining 28 congeners were used to model DR CALUX response (C-TEQs) in milk samples with different congener patterns. The theoretical underestimation of DR CALUX data could be mitigated by correcting the latter with the linear correlation experimentally obtained between C-TEQs and the WHO-TEQs. Under these conditions, the use as calibrants of reference samples with different analytical patterns could help those laboratories involved in a high throughput routine to set the most appropriate decision limits to optimize screening output.