Trace element contamination in fish impacted by bauxite red mud disposal in the Cassidaigne canyon (NW French Mediterranean).

From 1966 to 2015, the Gardanne alumina refinery discharged some 20 million tons of bauxite residue (called red mud) into the Cassidaigne Canyon (northwest French Mediterranean) with impacts on local ecosystem functioning. Although these red muds contained high levels of trace elements (TE), in particular titanium (Ti), vanadium (V), aluminum (Al) and arsenic (As), surprisingly, their impacts on fish contamination levels and the risk related to fish consumption have been little studied until now. Here, 11 trace elements (Al, As, Cd, Cr, Co, Cr, Mn, Ni, Pb, Ti and V) were analyzed in muscle and, when possible, liver, from 1308 fish of 26 species from an impacted zone in the vicinity of the Cassidaigne Canyon and a reference zone, unaffected by red mud disposals. Moreover, 66 arsenic speciation analyses were performed. Although the impact of human activities on the levels of fish contamination by trace elements is generally not easy to assess in situ because it is blurred by interaction with biological effects, we highlighted significant contamination of the fish species collected from the Cassidaigne Canyon, especially by the main trace elements attributable to the discharges of the Gardanne alumina refinery, namely Al, V and Ti. Moreover, inorganic toxic As concentrations were higher in the impacted zone. The results of this baseline research also confirmed the concern previously raised regarding Hg in Mediterranean organisms and that trace element contamination levels in fish are generally negatively related to fish length for all TE except Hg.

Exposure to contaminants and nutritional intakes in a French vegetarian population.

The NutriNet Santé study collected, on a voluntary basis, the dietary consumption of French vegetarian populations (N = 1766, including 188 vegan individuals) from 18 to 81 years (18-77 years for the vegan). Taking advantage of the availability of contamination data generated in the context of the second French total diet study, dietary exposures of French vegetarian populations to several contaminants were estimated. Results showed that exposures to persistent organic pollutants (PCBs, PCDD/Fs for instance) was dramatically lower than those of the general French population due to the non consumption of food of animal origins. On the other hand, exposures to phytoestrogens, some mycotoxins (T2 and HT2 toxins) and some trace elements (Cd, Al, Sn, Ni) were higher in the vegetarian population compared to those of the general population. Despite some limitations of this approach (both the consumption study and the total diet study were not aimed to estimate dietary exposure of the vegetarian populations), this study showed that dietary habits can dramatically influence the exposure of some contaminants.

Development and validation of a specific and sensitive gas chromatography tandem mass spectrometry method for the determination of bisphenol A residues in a large set of food items.

BPA-containing products are widely used in foodstuffs packaging as authorized within the European Union (UE no. 10/2011). Therefore, foods and beverages are in contact with BPA which can migrate from food contact material to foodstuffs. An accurate assessment of the exposure of the consumers to BPA is crucial for a non-ambiguous risk characterization. In this context, an efficient analytical method using gas chromatography coupled to tandem mass spectrometry (GC-MS/MS), in the selected reaction monitoring (SRM) mode, was developed for the quantification of BPA in foodstuffs at very low levels (<0.5µgkg(-1)). A standard operating procedure, based on the combination of two successive solid phase extractions (SPE), was developed for various liquid and solid foodstuffs. The use of (13)C12-BPA as internal standard allowed accurate quantification of BPA by isotopic dilution. Control charts based on both blank and certified materials have been implemented to ensure analytical data quality. The developed analytical method has been validated according to in-house validation requirements. R(2) was better than 0.9990 within the range [0-100µgkg(-1)], the trueness was 4.2%. Repeatability and within-laboratory reproducibility ranged from 7.5% to 19.0% and 2.5% to 12.2%, respectively, at 0.5 and 5.0µgkg(-1) depending on the matrices tested for. The detection and quantification limits were 0.03 and 0.10µgkg(-1), respectively. The reporting limit was 0.35µgkg(-1), taking into account the mean of the laboratory background contamination. The global uncertainty was 22.2% at 95% confidence interval.

Assessment of infant exposure to food chemicals: the French Total Diet Study design.

As part of the previous French Total Diet Studies (TDS) focusing on exposure to food chemicals in the population aged 3 years and older, the French Agency for Food, Environmental and Occupational Health & Safety (ANSES) launched a specific TDS on infants to complete its overall chemical food safety programme for the general population. More than 500 chemical substances were analysed in food products consumed by children under 3 years old, including nutrients, several endocrine disruptors resulting from human activities (polychlorinated biphenyls, dioxins and furans, brominated flame retardants, perfluoroalkyl acids, pesticide residues, etc.) or migrating from food contact materials such as bisphenol A or phthalates, but also natural substances such as mycotoxins, phytoestrogens and steroids. To obtain a representative and general view of infant food consumption, food items were selected based on results of a national consumption survey conducted specifically on this population. Moreover, a specific study on food was conducted on 429 households to determine which home-cooking practices are employed to prepare food consumed by infants. Overall, the targeted chemical substances were analysed in more than 450 food samples, representing the purchase and home-cooking practices of over 5500 food products. Foods included common foods such as vegetables, fruit or cakes as well as specific infant foods such as infant formula or jarred baby food. The sampling plan covered over 80% of the total diet. Specificities in infant food consumption and habits were therefore considered to define this first infant TDS. This study, conducted on a large scale and focusing on a particularly sensitive population, will provide accurate information on the dietary exposure of children under 3 years to food chemicals, especially endocrine disruptors, and will be particularly useful for risk assessment analysis under the remit of ANSES' expert committees.

Dietary exposure to perfluoroalkyl acids of specific French adult sub-populations: high seafood consumers, high freshwater fish consumers and pregnant women.

Perfluoroalkyl acids (PFAAs) are globally found in various media, including food and especially fishery products. In the present study, the dietary exposure to 15 perfluoroalkyl acids was assessed for 3 French adult populations, namely high seafood consumers, high freshwater fish consumers, and pregnant women. Purified food extracts were analysed by LC-MS/MS and PFBA, PFPA, PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUnA, PFTrDA, PFTeDA, PFBS, PFHxS, PFHpS, PFOS and PFDS were monitored and quantified according to the isotope dilution principle. Under lower bound (LB) hypothesis (i.e. contamination values

Attribution of the French human Salmonellosis cases to the main food-sources according to the type of surveillance data.

Salmonella are the most common bacterial cause of foodborne infections in France and ubiquitous pathogens present in many animal productions. Assessing the relative contribution of the different food-animal sources to the burden of human cases is a key step towards the conception, prioritization and assessment of efficient control policy measures. For this purpose, we considered a Bayesian microbial subtyping attribution approach based on a previous published model (Hald et al., 2004). It requires quality integrated data on human cases and on the contamination of their food sources, per serotype and microbial subtype, which were retrieved from the French integrated surveillance system for Salmonella. The quality of the data available for such an approach is an issue for many countries in which the surveillance system has not been designed for this purpose. In France, the sources are monitored simultaneously by an active, regulation-based surveillance system that produces representative prevalence data (as ideally required for the approach) and a passive system relying on voluntary laboratories that produces data not meeting the standards set by Hald et al. (2004) but covering a broader range of sources. These data allowed us to study the impact of data quality on the attribution results, globally and focusing on specific features of the data (number of sources and contamination indicator). The microbial subtyping attribution model was run using an adapted parameterization previously proposed (David et al., 2012). A total of 9076 domestic sporadic cases were included in the analyses as well as 9 sources among which 5 were common to the active and the passive datasets. The greatest impact on the attribution results was observed for the number of sources. Thus, especially in the absence of data on imported products, the attribution estimates presented here should be considered with caution. The results were comparable for both types of surveillance, leading to the conclusion that passive data constitute a potential cost-effective complement to active data collection, especially interesting because the former encompass a greater number of sources. The model appeared robust to the type of surveillance, and provided that some methodological aspects of the model can be enhanced, it could also serve as a risk-based guidance tool for active surveillance systems.

The Bayesian microbial subtyping attribution model: robustness to prior information and a proposition.

Attributing foodborne illnesses to food sources is essential to conceive, prioritize, and assess the impact of public health policy measures. The Bayesian microbial subtyping attribution model by Hald et al. is one of the most advanced approaches to attribute sporadic cases; it namely allows taking into account the level of exposure to the sources and the differences between bacterial types and between sources. This step forward requires introducing type and source-dependent parameters, and generates overparameterization, which was addressed in Hald's paper by setting some parameters to constant values. We question the impact of the choices made for the parameterization (parameters set and values used) on model robustness and propose an alternative parameterization for the Hald model. We illustrate this analysis with the 2005 French data set of non-typhi Salmonella. Mullner's modified Hald model and a simple deterministic model were used to compare the results and assess the accuracy of the estimates. Setting the parameters for bacterial types specific to a unique source instead of the most frequent one and using data-based values instead of arbitrary values enhanced the convergence and adequacy of the estimates and led to attribution estimates consistent with the other models' results. The type and source parameters estimates were also coherent with Mullner's model estimates. The model appeared to be highly sensitive to parameterization. The proposed solution based on specific types and data-based values improved the robustness of estimates and enabled the use of this highly valuable tool successfully with the French data set.

Assessment of dietary exposure to annatto (E160b), nitrites (E249-250), sulphites (E220-228) and tartaric acid (E334) in the French population: the second French total diet study.

The results of the assessment of the dietary exposure to annatto, nitrites, tartaric acid and sulphites within the framework of the second French total diet study (TDS) are reported. These 4 additives were selected from the Bemrah et al. study [Bemrah N, Leblanc JC, Volatier JL. 2008. Assessment of dietary exposure in the French population to 13 selected food colours, preservatives, antioxidants, stabilizers, emulsifiers and sweeteners. Food Addit Contam B. 1(1):2-14] on 13 food additives which identified a possible health risk for annatto, sulphites and nitrites and a lack of data for tartaric acid. Among the composite samples selected for the whole TDS, 524 were analysed for additives (a sample was analysed for a given additive when it was identified as a major contributor for this additive only): 130 for tartaric acid, 135 for nitrites, 59 for annatto and 200 for sulphites. Estimated concentrations (minimum lower bound to maximum upper bound) vary nationally from 0 to 9 mg/kg for annatto, 0 to 420 mg/kg for tartaric acid, 0 to 108 mg/kg for sulphites and 0 to 3.4 mg/kg for nitrites. Based on the analytical results, the dietary exposure was calculated for adults and children, separately, using lower bound and upper bound assumptions. The European ADIs for these 4 additives were not exceeded except for the dietary exposure for sulphites among 2.9% of the adult population, where the major contributors were alcoholic drinks and especially wine under both hypotheses (lower and upper bound).

Quantitative risk assessment of human salmonellosis from the consumption of a turkey product in collective catering establishments.

The quantitative risk assessment (QRA) approach recommended by the Codex Alimentarius Commission was used to assess the risk of human salmonellosis from the consumption of 'cordon bleu', a specific turkey product, in collective catering establishments (CCEs) of a French department. The complete process was modeled and simulated, from the initial storage in the CCE freezer to the consumption, using a Monte Carlo simulation software. Data concerning the prevalence of contaminated 'cordon bleu', the level of contamination of Salmonella, the cooking and storage process were collected from 21 CCEs and 8 retailers of 'cordon bleu' in the selected department. Thermal inactivation kinetics for Salmonella were established to estimate the effect of heat treatment on the concentration in the product and to calculate the dose that could be ingested by the consumer. The Beta-Poisson dose-response model of Rose and Gerba [Water Science and Technology 24 (1991) 29] with the specific parameters for Salmonella was used to estimate the probability of infection related to the ingestion of a particular dose and a factor was applied to estimate the probability of illness from ingestion. The individual risk of salmonellosis, the risk of outbreak and the number of cases were calculated using Monte Carlo simulation method. The risk of salmonellosis was close to zero when the 'cordons bleus' were cooked in the oven. Therefore, the risk was calculated for the fryer cooking since the insufficient cooking time observed was, sometimes, at the origin of low temperatures (37-89 degrees C). The influence of both the initial concentration of Salmonella in the product and the heat storage before consumption on the final risk was studied. For a high initial concentration of Salmonella in the product, when the 'cordons bleus' are fryer cooked, the average risk of salmonellosis was equal to 3.95 x 10(-3) without storage before consumption and 2.8 x 10(-4) if the product is consumed after storage. This paper presents the results of the QRA and discusses risk management options to minimize the risk of salmonellosis.

Quantification des risques sanitaires lies aux contaminations microbiologiques des aliments.

The four keystones of quantitative risk assessment are hazard identification, exposure assessment, dose-response assessment and risk characterization. This paper considers the different steps of risk assessment and their application to food microbiology. Traditionally, quantitative risk assessment has been viewed simply as a method to estimate risk. However, when we conduct a complete risk assessment including different factors from "farm to fork" it can serve to understand the risk process. Quantitative risk assessment can also provide valuable insights as how to best manage the risk.

[Quantitative risk assessment related to microbial food contamination]. / Quantification des risques sanitaires lies aux contaminations microbiologiques des aliments.

The four keystones of quantitative risk assessment are hazard identification, exposure assessment, dose-response assessment and risk characterization. This paper considers the different steps of risk assessment and their application to food microbiology. Traditionally, quantitative risk assessment has been viewed simply as a method to estimate risk. However, when we conduct a complete risk assessment including different factors from "farm to fork" it can serve to understand the risk process. Quantitative risk assessment can also provide valuable insights as how to best manage the risk.

Quantitative risk assessment of human listeriosis from consumption of soft cheese made from raw milk.

Microbial hazards have been identified in soft cheese made from raw milk. Quantification of the resulting risk for public health was attempted within the frame of the Codex Alimentarius Commission, 1995 approach to quantitative risk assessment, using Monte Carlo simulation software. Quantitative data could only be found for Listeria monocytogenes. The complete process of cheese making was modeled, from milking to consumption. Using data published on the different sources of milk contamination (environment and mastitis) and bacterial growth, distributions were assumed for parameters of the model. Equations of Farber, J.M., Ross, W.H., Harwing, J. (1996) for general and at-risk populations were used to link the ingested dose of L. monocytogenes to the occurrence of listeriosis. The probability of milk contamination was estimated to be 67% with concentration ranging from 0 to 33 CFU ml-1. The percentage of cheese with a predicted concentration of L. monocytogenes greater than 100 CFU g-1 was low (1.4%). The probability of consuming a contaminated cheese serving was 65.3%. Individual annual cumulative risk of listeriosis, in a population each consuming 50 servings of 31 g, ranged from 1.97 x 10(-9) to 6.4 x 10(-8) in a low-risk sub-population and 1.04 10(-6) to 7.19 10(-5) in a high-risk sub-population. The average number of expected cases of listeriosis per year was 57 for a high-risk sub-population and one for a low-risk healthy sub-population. When the frequency of environmental milk contamination was reduced in the model and L. monocytogenes mastitis was eliminated, the expected incidence of listeriosis decreased substantially; the average number of expected cases was reduced by a factor of 5. Thus the usefulness of simulation to demonstrate the efficiency of various management options could be demonstrated, even if results should be interpreted with care (as many assumptions had to be made on data and their distributions.