Développement d'une méthode d'extraction séquentielle de 36 composés phénoliques et 16 hydrocarbures aromatiques polycycliques à partir d'échantillons atmosphériques

Les hydrocarbures aromatiques polycycliques (HAP) sont des polluants organiques persistants émis dans l atmosphère par de nombreux processus de combustion. Ils sont particulièrement étudiés en raison de leur potentiel cancérigène et mutagène. Les phénols fonctionnalisés (chloro- et nitrophénols principalement) sont rejetés dans l atmosphère du fait de leur utilisation comme pesticides. Ils peuvent aussi provenir des combustions de déchets, du charbon, du bois et des émissions des véhicules diesel. Bien que certains d entre eux soient toxiques pour l homme et les végétaux, ils ne sont que très peu étudiés en France.Dans ce contexte, cette étude a pour objectif d élaborer une méthode séquentielle d extraction accélérée par solvant pressurisé à partir de la résine XAD-2 dopée. La première étape est l extraction de 36 composés phénoliques avec de l eau chaude alcaline à 150 C, ensuite, l extraction de 16 HAP se fait avec un mélange de n-hexane-acétone à 105 C. Les composés phénoliques sont concentrés par micro-extraction sur phase solide, suivie d une dérivation par silylation dans l injecteur d un chromatographe en phase gazeuse couplé à un spectromètre de masse pour l analyse. Les HAP sont quantifiés par chromatographie liquide à détection par fluorescence. L optimisation de la méthode d extraction a permis d obtenir des taux de recouvrement satisfaisants: 74-109% (chlorophénols), 60-101% (nitrophénols) et 85-114% (HAP). De plus, la méthode d analyse validée est rapide, sélective, fiable et sensible avec des limites de détection de 0,03-26 ng.mL-1. Grâce à une consommation minimale de solvants organiques, la méthode est également moins polluante de l environnement.Polycyclic aromatic hydrocarbons (PAH) are persistent organic pollutants. They are emitted into the atmosphere by many combustion processes and they have been particularly studied due to their potential carcinogenic and/or mutagenic properties. Functionalized phenols (e.g. chloro- and nitro-phenols) are released into the atmosphere because of their use as pesticides. They can also be emitted from diesel engines, waste incineration, coal and wood combustions. Some of them are known or suspected to be highly toxic to human health and plants. However, they are poorly studied in France.In this laboratory study, accelerated solvent extraction was used for the sequential extraction of 36 phenolic compounds and 16 PAH from spiked XAD-2 resin. The procedure is based on hot alkaline water extraction (150 C) of polar phenolic compounds, followed by acetone-n-hexane (1:1, v/v) extraction of PAH at 105 C. The phenolic compounds in the aqueous extract are preconcentrated onto solid-phase microextraction fiber, followed by desorption and injection-port derivatization prior to gas chromatography analysis with mass spectrometry detection. The PAH, included in the second fraction, are preconcentrated by rotary evaporator and analyzed by liquid chromatography with fluorescence detection.Optimization of the extraction method allowed achieving high recoveries: 74-109% (chlorophenols), 60-101% (nitrophenols) and 85-114% (PAH). The validated analytical procedure is fast, selective, reliable and sensitive with detection limits of 0.03-26 ng.mL-1. Furthermore, the method is environmentally friendly, as it consumes much less harmful organic solvents compared to conventional extraction methods.STRASBOURG-Sc. et Techniques (674822102) / SudocSudocFranceLebanonFRL

Proportionate and Absolute Vascular Disease Mortality by Race and Sex in the United States From 1999 to 2019

Background Despite the known significant morbidity and mortality associated with cardiovascular disease and peripheral vascular disease (PVD), contemporary data describing racial demographics in PVD mortality are scarce. Methods and Results Using the multiple causes of death file from the Centers for Disease Control and Prevention’s Wide‐Ranging Online Data for Epidemiologic Research, we analyzed the trends of age‐adjusted mortality (AAMR) for PVD and its subtypes (aortic aneurysm/dissection, arterial thrombosis, venous thrombosis/disease, pulmonary embolism), by race and sex between 1999 and 2019. Of the 17 826 871 deaths attributed to cardiovascular disease, a total of 888 187 (5.0%) PVD deaths were analyzed during the study period (12.4% Black, 85.6% White). Between 1999 and 2019, AAMR for PVD decreased by 52% (24.8–11.8 per 100 000 people) in the overall population. Despite a decrease in the overall mortality across all race and sex groups, Black men and Black women continued to have higher mortality for PVD (1.5×), aortic dissection (1.8×), arterial thrombosis (1.3×), and venous thrombosis/disease (2.0×) mortality compared with White men and White women in 2019. While there was a 53% decrease in PVD among White individuals (AAMR 24.5–11.5 per 100 000), there was only a 43% decrease (30.0–17.1) in PVD AAMR in Black individuals between 1999 and 2019. The ratio of PVD AAMR increased from 1.2 (1999) to 1.5 (2019) in Black men/White men and from to 1.3 (1999) to 1.5 (2019) in Black women/White women. Similar trends were noted in aortic dissection (Black men/White men, 1.2–1.8; and Black women/White women, 1.5–1.7), arterial thrombosis (Black men/White men, 1.0–1.3; and Black women/White women, 0.9–1.3), and venous thrombosis/disease (Black men/White men, 1.7–1.8; and Black women/White women, 1.7–2.0). Conclusions In this retrospective review of death certificate data in the United States, we demonstrate continued significant disparities between Black and White populations in PVD mortality and its subtypes. Future studies should investigate etiologies and social determinants of PVD mortality