In-house validation of chromatographic speciation methods for arsenic in fishery products

The relatively high concentrations of arsenic found in shellfish in recent years have contributed to raise the threshold of attention of European Union, in terms of food security. Among the various factors that influence the toxicity of arsenic, the chemical form is of particular significance, given the high toxicity of the inorganic form in respect of the organic that frequently contaminates fishery products. The Expert Committee of FAO / WHO defined a provisional tolerable weekly intake (PTWI) of 15 mg/kg b.w. only for the inorganic form and, in view of definition of residual limits for arsenic in fish, it becomes necessary to have analytical methods able to differentiate inorganic form from the organic ones (e.g. monomethyland dimethylarsenic acid, arsenobetaine, arsenocholine). The purpose of this study was to optimize and validate an analytical method for the speciation of arsenic in fishery products, that could identify and quantify the organic forms of arsenic. Screening of organic forms of arsenic was carried out using HPLC (high performance liquid chromatography) coupled to a tandem mass spectrometry detector, while determination of total arsenic was carried out using the atomic absorption spectroscopy. The validation procedure was conducted according to the requirements of the European Community to allow the use of the present method by the Official Control laboratories. The matrices considered for method optimization and validation have been fish, molluscs and crustaceans from the coasts of southern Italy. Obtained results allowed the method to enter within the routinely activities of the laboratory and require method accreditation

EFFECTS OF NDL-PCB AND TCDD ON INTESTINAL EPITHELIAL CELLS HOMEOSTASIS

Polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins (PCDD) are persistent organic pollutants (POPs) recognized as causing adverse effects on humans, animals and environment. Exposure occurs mainly through the consumption of contaminated food, in particular those of animal origin. the aim of the current study was to evaluate the effects of three ndl-PCB congeners, PCB 138, PCB 153 and PCB 180, and tetrachlorodibenzo-p-dioxins (TCDD), alone and differently combined, on non tumorigenic rat intestinal epithelial cell line (IEC-6). The results of the current study showed that ndl-PCBs and TCDD reduced significantly cell viability only at the highest concentrations (50-100 µM and 0.1-1 µM, respectively); such effect was not linked to apoptosis induction or cell cycle arrest. The contemporary presence of more than one contaminant (differently combined) did not induce any enhancement of effects on IEC-6 cell line. Intestinal restitution was not affected by low non cytotoxic concentrations of ndl-PCBs and TCDD. The results of the current study highlight the need to continue the evaluation of toxic properties of ndl-PCBs, which represent a less studied PBCs; such studies could provide useful information in particular in term of risk assessment

Levels of heavy metals in liver and kidney of dogs from urban environment

Lead, cadmium and mercury were detected in liver and kidney tissue of dogs from an urban habitat. Samples were digested in a microwave system and analyzed by atomic absorption spectroscopy. Results of the current study showed that at least one of the three heavy metals was detected in tissues of all examined dogs. These findings make us suppose that humans are exposed to the same heavy metals similar to those of dogs that are exposed since they share the same environment. Mercury concentrations detected in kidney of household dogs were higher than stray dogs, therefore the involvement of pet food in exposure to mercury can be supposed

Heavy Metal Levels in Dog Liver and Kidney in Naples (Campania, Italy)

The aim of the current study was to carry out a retrospective analysis of heavy metal (Pb, Cd, and Hg) levels in liver and kidney of 38 dogs living in an urban habitat (city of Naples). Tissues were homogenized, digested in a microwave digestion system, and analyzed by atomic absorption spectrometry. The results of this study showed generally low levels of heavy metals in tissues of all examined dogs; only mercury concentrations in kidneys of pet dogs were higher than in stray dogs, and no significant age-dependent differences in metal levels were shown between the two groups. In conclusion, these results suggest the involvement of ad hoc-formulated pet food exposure to heavy metals in domestic animals

LEVELS OF HEAVY METALS IN ITALIAN MARKETED CANNED TUNA

Fish products are essential and irreplaceable components of human diet; nevertheless, they could result in a risk to the health of consumers due to the potential content of some xenobiotics such as heavy metals and persistent organic contaminants (Debeka et al., 2004; Storelli et al., 2005). Constant control network and surveys are valuable tools in order to prevent such risk and to ensure product quality and consumers??? safety. The aim of the current study was to measure the levels of some heavy metals (Hg, Pb, Cd) in samples of marked canned tuna in olive oil. The results showed that levels of Cd and Hg were always within the law limits and, in many samples, below the detection limit. Pb was found in concentrations exceeding the law limits in 9.8% of the analyzed samples. In conclusion, the results of the current study, quite reassuring in terms of food safety, highlighted the need to constantly monitor the levels of some chemical contaminants in fish products such as heavy metals that might endanger the health of the consumers

Heavy Metals in Canned Tuna from Italian Markets

Fish is a good source of nutrients for humans but can pose a risk to human health because of the possible presence of some xenobiotics such as heavy metals and persistent organic contaminants. Constant monitoring is needed to minimize health risks and ensure product quality and consumer safety. The aim of the present study was to use atomic absorption spectrometry to determine the concentrations of some heavy metals (Hg, Pb, and Cd) in tuna packaged in different kinds of packages (cans or glass) in various countries (Italy and elsewhere). Concentrations of Cd and Hg were within the limits set by European Commission Regulation (EC) No 1881/2006 and in many samples were below the detection limit. Pb concentrations exceeded European limits in 9.8% of the analyzed samples. These results are reassuring in terms of food safety but highlighted the need to constantly monitor the concentrations of heavy metals in fish products that could endanger consumer health

Method for speciation of organoarsenic in mussels by liquid chromatography coupled to electrospray ionization and QTRAP tandem mass spectrometry

Arsenic toxicity to humans critically depends on its chemical form. The Expert Committee of the FAO/WHO defined a tolerable intake only for inorganic arsenic although there are evidences on toxicity of some organoarsenic compounds. Arsenobetaine (AsB), arsenocholine (AsC), dimethylarsinic acid (DMA) and monomethylarsonic acid (MMA) are abundant species in shellfish. Herein, we present a fast and reliable method for speciation of organic arsenic in mussels by liquid chromatography coupled to electrospray tandem mass spectrometry on triple quadrupole (LC/ESI-MS/MS) with parallel determination of total arsenic by atomic absorption spectrophotometry (AAS) aimed at setting tolerable levels for both inorganic and organic arsenic in fishery products; methods performances were evaluated in terms of mean recoveries of the analytes, precision, specificity, limits of quantification (LOQs) and limits of detection (LODs). Finally, the described approach was employed to perform a survey about the contamination of organic arsenic in mussels from Campania region (Southern Italy)

Accreditation of a sreening method for non dioxin-like polychlorinated biphenyls (NDL-PCB) detection in fishery products according to European legislation

European Commission Regulation 882/2004/EC requires that official control laboratories for foodstuffs in the member states are certified according to UNI EN ISO/IEC 17025:2005 (general requirement for the competence of calibration and testing laboratories). This mandatory requirement has resulted in a continuous adaptation and development of analytical procedures. The aim of this study was to develop a method for semiquantitative screening of polychlorinated biphenyls in fish for human consumption. According to the Commission Decision 657/2002/CE, the detection capability, the precision, the selectivity-specificity, and applicability-ruggedness-stability were determined to validate the method. Moreover, trueness was verified. This procedure resulted in rapid execution, which allowed immediate and effective intervention by the local health authorities to protect the health of consumers. Finally, the procedure has been recognized by the Italian accrediting body, ACCREDIA

Predicting dioxin-like PCBs soil contamination levels using milk of grazing animal as indicator

Dioxin-like PCBs (dl-PCBs) are ubiquitous persistent organic pollutants of recognized negative effects onhuman health. Assessing highly polluted areas should be an important public health issue. This studyproposes to use the milk of grazing animals as a bioindicator of dl-PCB contamination in the environment.The hypothesis is that milk concentration of dl-PCBs are related to soil concentrations of these compounds,and that soils are generally reflective of a larger environmental issue of dl-PCB contamination.In this study, we evaluate the possibility of predicting soil concentrations using milk of sheep, cowsand buffalos in a spatial model. For this purpose, samples of soil and milk collected in Campania (Italy)were introduced in a GIS platform to perform geostatistical analysis for building a simple predictivemodel. The ordinary least squares regressions (OLS) showed a statistically significant correlation(p < 0.05) between soil and milk contamination. However, this relationship was spatially variable. Thus,a geographically weighted regression (GWR) was performed, obtaining R2 values of 0.91, 0.77 and 0.66 forsheep’s, buffalo’s and cow’s milk respectively. Assessed the mathematical relationships between the variables,new data was introduced to evaluate the performance of the model. Predictions of soil contaminationwith dl-PCBs using sheep’s, cow’s and buffalo’s milk showed a mean error of 23%, 25% and 36%respectively. According to these results the sheep’s milk can be considered the best bioindicator of dl-PCBs contamination among the three species. The results of this project evidence the potentialities ofthe proposed approach to assess bioindicator performance in a spatial predictive model.[...