Quantification of light Polycyclic Aromatic Hydrocarbons in seafood samples using on-line Dynamic HeadSpace extraction, ThermoDesorption, Gas Chromatography tandem Mass Spectrometry, based on an isotope dilution approach

The aim of our work was to develop an analytical strategy to quantify naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene and anthracene in fish products by on-line dynamic headspace extraction, followed by thermodesorption injection and gas chromatography analysis coupled with tandem mass spectrometry using electron ionization mode (DHS-TD-GC-EI-MS/MS). The developed protocol used 1 g of freeze-dried or oil sample supplemented with perdeuterated light PAHs. The sample was heated at [90 - 100°C], the headspace of the sample was swept by nitrogen and the trapping of the PAHs was carried out on a Tenax-type adsorbent placed at 25°C. Analytes were thermodesorbed at 300°C from the dried adsorbant and then cryofocused on a cooled injection system (CIS) at ¬25°C before injection (12°C s−1 up to 300°C). The chromatographic separation of PAHs was carried out on a 5-MS type column (30 m × 0.25 mm, 0.25 μm) and the acquisition of the signals was performed in SRM following the transitions, involving the loss of one or two hydrogen atoms from the molecular ion. In view of the principle of extraction, the calibration curve was performed on a representative matrix or using the standard addition method. Quantification limits were determined between 0.01 and 0.6 ng g−1 of matrix from the method blank results. The method was validated by a series of multi-level supplemented matrix assays and by the analysis of a reference material from an inter-laboratory test (mussels, IAEA-432). The average of the expanded measurement uncertainty was from 9 to 44% for the four lightest PAHs, except for fluorene when the sample incubation was set at 90°C. Occurrence measurements were performed on almost two hundred samples of molluscs, echinoderms and fish. The results have shown a quantification frequency greater than 66% for naphthalene and fluorene, at concentrations below a few ng g−1 of dry matter of fishery products. With this methodology, the light PAHs occurrence can now be measured in a wider range of foodstuffs in order to better characterize their contamination trends and the associated risk simultaneously.

Focus on the GC-HRMS based analytical development for characterization of human internal exposure to pesticides, in a multiplex inter-laboratory approach

International audienceProviding a methodology for broad assessment of human internal exposure to pesticides, via suspect screening, based on urine samples.Development of an unique protocol for analysis of a single urine sample by 3 complementary analytical platforms providing extensive picture of the internal exposure to pesticides, including both parent compounds and metabolites

Widening exposome exploration by means of complementary HRMS analytical platforms: use case on pesticide exposure

International audienceHuman exposure to food and environmental contaminants (such as pesticides) is generally estimated by indirect methods. Targeted bio-monitoring is a way to assess the internal exposure on a limited number of substances, needing large sample amounts for analyses as rigorous and sensitive as possible. Thus, the human health risks associated with multi-exposure to complex mixtures currently remain under-explored.In this context, the SCREENPEST project aims at providing a unified methodology for large-scale characterisation of human internal exposure to pesticides, via a "suspect profiling" approach, using urine

Widening exposome exploration by means of complementary HRMS analytical platforms: use case on pesticide exposure

International audienceHuman exposure to food and environmental contaminants (such as pesticides) is generally estimated by indirect methods. Targeted bio-monitoring is a way to assess the internal exposure on a limited number of substances, needing large sample amounts for analyses as rigorous and sensitive as possible. Thus, the human health risks associated with multi-exposure to complex mixtures currently remain under-explored.In this context, the SCREENPEST project aims at providing a unified methodology for large-scale characterisation of human internal exposure to pesticides, via a "suspect profiling" approach, using urine

Widening exposome exploration by means of complementary HRMS analytical platforms: use case on pesticide exposure

International audienceHuman exposure to food and environmental contaminants (such as pesticides) is generally estimated by indirect methods. Targeted bio-monitoring is a way to assess the internal exposure on a limited number of substances, needing large sample amounts for analyses as rigorous and sensitive as possible. Thus, the human health risks associated with multi-exposure to complex mixtures currently remain under-explored.In this context, the SCREENPEST project aims at providing a unified methodology for large-scale characterisation of human internal exposure to pesticides, via a "suspect profiling" approach, using urine

Widening exposome exploration by means of complementary HRMS analytical platforms: use case on pesticide exposure

International audienceHuman exposure to food and environmental contaminants (such as pesticides) is generally estimated by indirect methods. Targeted bio-monitoring is a way to assess the internal exposure on a limited number of substances, needing large sample amounts for analyses as rigorous and sensitive as possible. Thus, the human health risks associated with multi-exposure to complex mixtures currently remain under-explored.In this context, the SCREENPEST project aims at providing a unified methodology for large-scale characterisation of human internal exposure to pesticides, via a "suspect profiling" approach, using urine

Nouvelle approche de spectrométrie de masse haute résolution multiplexée pour une évaluation exhaustive de l’exposition interne aux pesticides

National audienc

Persistent organochlorine pesticides in periprostatic adipose tissue from men with prostate cancer: Ethno-geographic variations, association with disease aggressiveness

International audienceAlthough several studies have examined the relationship between organochlorine pesticides (OCPs) and prostate cancer (PCa) risk, no data are available concerning the association between OCPs concentrations in periprostatic adipose tissue (PPAT), which reflects cumulative exposure, and PCa aggressiveness. Moreover, no previous study has compared OCPs exposure in two distinct ethno-geographical populations. The objectives were to analyze OCPs in PPAT of PCa patients from either Mainland France or French West Indies in correlation with features of tumor aggressiveness, after adjusting for potential confounders such age, BMI, and polyunsaturated fatty acid (PUFA) content of PPAT. PPAT was analyzed in 160 patients (110 Caucasians and 50 African-Caribbeans), 80 with an indolent tumor (ISUP group 1 + pT2), and 80 with an aggressive tumor (ISUP group more than 3 + pT3). The concentrations of 29 OCPs were measured in PPAT concomitantly with the characterization of PUFA content. Exposure patterns of OCPs differed according to the ethno-geographical origin. Most OCPs were found at higher concentration in Caucasian patients, whereas pp’-DDE content was twice as high in African-Caribbeans. Chlordecone was only detected in PPAT from African-Caribbean patients. Most OCP concentrations were positively correlated with age, and some with BMI. After adjusting for age, BMI, and PUFA composition of PPAT, no significant association was found between OCPs content and risk of aggressive disease, except of mirex which appeared inversely associated with aggressive features of PCa in Caucasian patients. These results highlight a significant ethno-geographic variation in internal exposure to OCPs, which likely reflects differences in consumption patterns. The inverse relationship observed between mirex concentration and markers of PCa aggressiveness need to be further investigated