HBM4EU chromates study - Overall results and recommendations for the biomonitoring of occupational exposure to hexavalent chromium

Exposure to hexavalent chromium [Cr(VI)] may occur in several occupational activities, e.g., welding, Cr(VI) electroplating and other surface treatment processes. The aim of this study was to provide EU relevant data on occupational Cr(VI) exposure to support the regulatory risk assessment and decision-making. In addition, the capability and validity of different biomarkers for the assessment of Cr(VI) exposure were evaluated. The study involved nine European countries and involved 399 workers in different industry sectors with exposures to Cr(VI) such as welding, bath plating, applying or removing paint and other tasks. We also studied 203 controls to establish a background in workers with no direct exposure to Cr(VI). We applied a cross-sectional study design and used chromium in urine as the primary biomonitoring method for Cr(VI) exposure. Additionally, we studied the use of red blood cells (RBC) and exhaled breath condensate (EBC) for biomonitoring of exposure to Cr(VI). Personal measurements were used to study exposure to inhalable and respirable Cr(VI) by personal air sampling. Dermal exposure was studied by taking hand wipe samples. The highest internal exposures were observed in the use of Cr(VI) in electrolytic bath plating. In stainless steel welding the internal Cr exposure was clearly lower when compared to plating activities. We observed a high correlation between chromium urinary levels and air Cr(VI) or dermal total Cr exposure. Urinary chromium showed its value as a first approach for the assessment of total, internal exposure. Correlations between urinary chromium and Cr(VI) in EBC and Cr in RBC were low, probably due to differences in kinetics and indicating that these biomonitoring approaches may not be interchangeable but rather complementary. This study showed that occupational biomonitoring studies can be conducted successfully by multi-national collaboration and provide relevant information to support policy actions aiming to reduce occupational exposure to chemicals.This work has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement No 733032 and received co-funding from the author's organizations and/or Ministries. Luxembourg entered the study at a later stage and thus financed the study at its own means.S

HBM4EU chromates study - Overall results and recommendations for the biomonitoring of occupational exposure to hexavalent chromium

Exposure to hexavalent chromium [Cr(VI)] may occur in several occupational activities, e.g., welding, Cr(VI) electroplating and other surface treatment processes. The aim of this study was to provide EU relevant data on occupational Cr(VI) exposure to support the regulatory risk assessment and decision-making. In addition, the capability and validity of different biomarkers for the assessment of Cr(VI) exposure were evaluated. The study involved nine European countries and involved 399 workers in different industry sectors with exposures to Cr(VI) such as welding, bath plating, applying or removing paint and other tasks. We also studied 203 controls to establish a background in workers with no direct exposure to Cr(VI). We applied a cross-sectional study design and used chromium in urine as the primary biomonitoring method for Cr(VI) exposure. Additionally, we studied the use of red blood cells (RBC) and exhaled breath condensate (EBC) for biomonitoring of exposure to Cr(VI). Personal measurements were used to study exposure to inhalable and respirable Cr(VI) by personal air sampling. Dermal exposure was studied by taking hand wipe samples. The highest internal exposures were observed in the use of Cr(VI) in electrolytic bath plating. In stainless steel welding the internal Cr exposure was clearly lower when compared to plating activities. We observed a high correlation between chromium urinary levels and air Cr(VI) or dermal total Cr exposure. Urinary chromium showed its value as a first approach for the assessment of total, internal exposure. Correlations between urinary chromium , Cr(VI) in EBC and Cr in RBC were low, probably due to differences in kinetics and indicating that these biomonitoring approaches may not be interchangeable but rather complementary. This study showed that occupational biomonitoring studies can be conducted successfully by multi-national collaboration and provide relevant information to support policy actions aiming to reduce occupational expo-sure to chemicals

Evaluation of chromium in red blood cells as an indicator of exposure to hexavalent chromium: An in vitro study

International audienceChromium(VI) compounds are classified as carcinogenic to humans. Whereas chromium measurements in urine and whole blood (i.e., including plasma) are indicative of recent exposure, chromium in red blood cells (RBC) is attributable specifically to Cr(VI) exposure. Before recommending Cr in RBC as a biological indicator of Cr(VI) exposure, in-vitro studies must be undertaken to assess its reliability. The present study examines the relationship between the chromium added to a blood sample and that subsequently found in the RBC. After incubation of total blood with chromium, RBC were isolated, counted and their viability assessed. Direct analysis of chromium in RBC was conducted using Atomic Absorption Spectrometry. Hexavalent, but not trivalent Cr, was seen to accumulate in the RBC and we found a strong correlation between the Cr(VI) concentration added to a blood sample and the amount of Cr in RBC. This relationship appears to be independent of the chemical properties of the human blood samples (e.g., different blood donors or different reducing capacities). Even though in-vivo studies are still needed to integrate our understanding of Cr(VI) toxicokinetics, our findings reinforce the idea that a single determination of the chromium concentration in RBC would enable biomonitoring of critical cases of Cr(VI) exposure.Bien que les travailleurs puissent être exposés à du chrome métallique, du Cr (III) et du Cr (VI) sur le lieu de travail, les composés du Cr (VI) sont particulièrement préoccupants en termes de risques pour la santé. Après absorption par ingestion, inhalation et / ou diffusion percutanée, les ions Cr (VI) sont transportés dans le sang et pénètrent les globules rouges. En raison de la réduction intracellulaire du Cr (VI) en Cr (III) et en même temps, de leur liaison aux protéines, les globules rouges représentent un organe cible facilement accessible pour la détermination quantitative de chrome après une exposition aux composés du Cr (VI). Alors que les mesures de chrome dans l'urine et le sang total (y compris le plasma) sont révélateurs d'une exposition récente, le chrome dans les globules rouges est attribuable spécifiquement à une exposition au Cr (VI) et ce, pendant une période correspondant à la durée de vie des globules - une période d'exposition beaucoup plus longue.Avant que le Cr dans les globules rouges puisse être utilisé comme un indicateur biologique d'exposition (IBE) au Cr (VI), sa fiabilité doit être évaluée dans des études in vitro. On examine la relation entre le chrome ajouté à un échantillon de sang et à la quantité de Cr retrouvée dans les globules. L'influence de l'état d'oxydation du Cr, sa spéciation, les paramètres d'incubation, la concentration d'acide ascorbique et l’influence des donneurs de sang ont été étudiés. Bien que des études in-vivo soient encore nécessaires pour mieux comprendre la toxicocinétique du Cr (VI), nos résultats suggèrent que le Cr dans GR devrait sérieusement être considéré comme un IBE pour Cr (VI)

Minéralisation de nanoparticules de TiO2 pour la détermination du titane dans les tissus de rat

International audienceIn order to draw appropriate conclusions about the possible adverse biological effects of titanium dioxide nanoparticles (TiO 2-NPs), the so-called "dose-effect" relationship must be explored. This requires proper quantification of titanium in complex matrices such as animal organs for future toxicological studies. This study presents the method development for mineralizing TiO 2-NPs for analysis of biological tissues. We compared the recovery and quantification limits of the four most commonly used mineralization methods for metal oxides. Microwave-assisted dissolution in an HNO 3-HF mixture followed by H 2 O 2 treatment produced the best results for a TiO 2-NPs suspension, with 96 ± 8% recovery and a limit of quantification as low as 0.9 μg/L. This method was then used for the determination of titanium levels in tissue samples taken from rats. However, our tests revealed that even this method is not sensitive enough for quantifying titanium levels in single olfactory bulbs or hippocampus in control animals.Afin de tirer des conclusions appropriées sur les effets biologiques néfastes possibles des nanoparticules de dioxyde de titane (TiO 2-NP), la relation dite «dose-effet» doit être explorée. Cela nécessite une quantification appropriée du titane dans des matrices complexes telles que des organes animaux pour de futures études toxicologiques. Cette étude présente le développement de la méthode de minéralisation des TiO 2-NP pour l'analyse des tissus biologiques. Nous avons comparé les limites de récupération et de quantification des quatre méthodes de minéralisation les plus couramment utilisées pour les oxydes métalliques. La dissolution assistée par micro-ondes dans un mélange HNO 3-HF suivie d'un traitement H 2 O 2 a donné les meilleurs résultats pour une suspension de TiO 2-NPs, avec une récupération de 96 ± 8% et une limite de quantification aussi basse que 0,9 μg / L. Cette méthode a ensuite été utilisée pour la détermination des niveaux de titane dans des échantillons de tissus prélevés sur des rats. Cependant, nos tests ont révélé que même cette méthode n'est pas assez sensible pour quantifier les niveaux de titane dans les bulbes olfactifs uniques ou l'hippocampe chez les animaux témoins

Study of potential transfer of aluminum to the brain via the olfactory pathway

International audienceMany employees in the aluminum industry are exposed to a range of aluminum compounds by inhalation, and the presence of ultrafine particles in the workplace has become a concern to occupational health professionals. Some metal salts and metal oxides have been shown to enter the brain through the olfactory route, bypassing the blood-brain barrier, but few studies have examined whether aluminum compounds also use this pathway. In this context, we sought to determine whether aluminum was found in rat olfactory bulbs and whether its transfer depended on physicochemical characteristics such as solubility and granulometry. Aluminum salts (chloride and fluoride) and various nanometric aluminum oxides (13 nm, 20 nm and 40–50 nm) were administered to rats by intranasal instillation through one nostril (10 μg Al/30 μL for 10 days). Olfactory bulbs (ipsilateral and contralateral relative to instilled nostril) were harvested and the aluminum content was determined by graphite furnace atomic absorption spectrometry after tissue mineralization. Some transfer of aluminum salts to the central nervous system via the olfactory route was observed, with the more soluble aluminum chloride being transferred at higher levels than aluminum fluoride. No cerebral translocation of any of the aluminas studied was detected.De nombreux salariés de l'industrie de l'aluminium sont exposés à de nombreux composés contenant de l'aluminium par inhalation et la présence de particules ultrafines sur le lieu de travail est devenue une préoccupation pour les professionnels de la santé au travail. Certains travaux ont montré que des sels de métaux et oxydes métalliques pouvaient pénétrer dans le cerveau par la voie olfactive en court-circuitant la barrière hémato-encéphalique, mais peu d'études ont cherché à savoir si les composés de l’aluminium empruntaient également cette voie. Dans ce contexte, cette étude vise à déterminer si l'aluminium pouvait migrer dans les bulbes olfactifs de rat et si ce transfert dépendait des caractéristiques physico-chimiques telles que la solubilité et la granulométrie. Les sels d'aluminium (chlorure et fluorure) et divers oxydes d'aluminium sous forme nanométrique (13 nm, 20 nm et 40-50 nm) ont été administrés à des rats par instillation intranasale (10 ìg Al / 30 microL pendant 10 jours). Les bulbes olfactifs (ipsilatéral et contralatéral par rapport à la narine instillée) ont été collectés et la concentration en aluminium a été déterminée par spectrométrie d'absorption atomique à four graphite après minéralisation des tissus. Il a été montré que les sels d’aluminium migraient vers le système nerveux central via la voie olfactive et que le chlorure d'aluminium, sel plus soluble le faisait davantage que le fluorure d'aluminium. Aucune translocation cérébrale des alumines étudiées n'a été mise en évidence

Is the blood of a surgeon performing HIPEC contaminated by irinotecan, its major metabolites and platinum compounds?

International audienceAbstract Objectives Hyperthermic intraperitoneal chemotherapy (HIPEC) is a beneficial surgical technique for patients, but the surgeons are being exposed to cytotoxic drugs. Few biomonitoring studies were led on blood samples in the context of HIPEC. This study aimed to evaluate the surgeon’s plasmatic and red blood cell (RBC) contamination by irinotecan, two of its major metabolites and platinum compounds. Methods HIPEC procedures performed using the coliseum techniques were observed between September 2015 and April 2018 in a French comprehensive cancer center. Irinotecan and its metabolites SN-38 and APC were dosed by UHPLC with a limit of quantification determined at 50 pg/mL. Platinum compounds were dosed by inductively coupled plasma mass spectrometry with a limit of quantification determined at 16 pg/mL. Results Despite collective and personal protective equipment, 80% of plasma samples were contaminated by irinotecan and 33% by platinum compounds out of 21. The results showed that the surgeon was contaminated after HIPEC and even after a period of HIPEC inactivity. Nineteen percent of plasmatic samples and 45% of RBC samples were contaminated by SN-38, the active metabolite of irinotecan. APC was only found in some RBC samples (33%). Conclusions Even if this study shows blood contamination by irinotecan, two of its major metabolites (including active SN-38) and platinum compounds both in the plasma and RBC of a surgeon performing the HIPEC procedures, further studies should be performed to confirm these results. Additional studies should be carried out to further investigate the contamination in the context of HIPEC and more broadly in the hospital

HBM4EU chromates study: usefulness of measurement of blood chromium levels in the assessment of occupational Cr(VI) exposure

Occupational exposures to hexavalent chromium (Cr(VI)) can occur in welding, hot working stainless steel processing, chrome plating, spray painting, and coating activities. Recently, within the human biomonitoring for Europe initiative (HBM4EU), a study was performed to assess the suitability of different biomarkers to assess the exposure to Cr(VI) in various job tasks. Blood-based biomarkers may prove useful when more specific information on systemic and intracellular bioavailability is necessary. To this aim, concentrations of Cr in red blood cells (RBC-Cr) and in plasma (P–Cr) were analyzed in 345 Cr(VI) exposed workers and 175 controls to understand how these biomarkers may be affected by variable levels of exposure and job procedures. Compared to controls, significantly higher RBC-Cr levels were observed in both plating and paint application workers, but not in welders, while all the 3 groups had significantly greater P–Cr concentrations. RBC-Cr and P–Cr in chrome platers showed a high correlation with Cr(VI) in inhalable dust, outside respiratory protective equipment (RPE), while such correlation could not be determined in welders. In platers, the use of RPE had a significant impact on the relationship between blood biomarkers and Cr(VI) in inhalable and respirable dust. Low correlations between P–Cr and RBC-Cr may reflect a difference in kinetics. This study showed that Cr-blood-based biomarkers can provide information on how workplace exposure translates into systemic availability of Cr(III) (extracellular, P–Cr) and Cr(VI) (intracellular, RBC-Cr). Further studies are needed to fully appreciate their use in an occupational health and safety context.info:eu-repo/semantics/publishedVersio

HBM4EU chromates study - the measurement of hexavalent and trivalent chromium in exhaled breath condensate samples from occupationally exposed workers across Europe

The aim of this study was to investigate the practicability of exhaled breath condensate (EBC) as a biological matrix to detect and measure hexavalent chromium (Cr(VI)) and trivalent chromium (Cr(III)) in workers occupationally exposed to Cr(VI). EBC samples were collected from workers in France, Finland, Italy, The Netherlands and the United Kingdom from three different target activities: chrome platers, stainless steel welders and surface treatment workers. Pre and post working week EBC samples were collected from 177 exposed workers and 98 unexposed workers (control group). Hyphenated chromatography systems with inductively coupled plasma - mass spectrometry (ICP-MS) were for the analysis. The results showed that the occupationally exposed workers had significantly higher levels of Cr(VI) and Cr(III) than the control group. Chrome platers exhibited the highest Cr(VI) levels in their EBC samples, with a significant increase from their pre to post samples for both Cr(VI) and Cr(III). A significant difference was also found between pre and post EBC samples for Cr(III) in welders. This study has shown that EBC has the potential to be a valid, non-invasive biological matrix to assess occupational exposure to Cr(VI) and Cr(III) for biological monitoring assessment, with the ability to detect low level inhalation exposures

HBM4EU chromates study - Usefulness of measurement of blood chromium levels in the assessment of occupational Cr(VI) exposure

Occupational exposures to hexavalent Chromium (Cr(VI)) can occur in welding, hot working stainless steel processing, chrome plating, spray painting and coating activities. Recently, within the human biomonitoring for Europe initiative (HBM4EU), a study was performed to assess the suitability of different biomarkers to assess the exposure to Cr(VI) in various job tasks. Blood-based biomarkers may prove useful when more specific infor-mation on systemic and intracellular bioavailability is necessary. To this aim, concentrations of Cr in red blood cells (RBC-Cr) and in plasma (P-Cr) were analyzed in 345 Cr(VI) exposed workers and 175 controls to understand how these biomarkers may be affected by variable levels of exposure and job procedures.Compared to controls, significantly higher RBC-Cr levels were observed in bath plating and paint application workers, but not in welders, while all the 3 groups had significantly greater P-Cr concentrations. RBC-Cr and P-Cr in chrome platers showed a high correlation with Cr(VI) in inhalable dust, outside respiratory protective equipment (RPE), while such correlation could not be determined in welders. In platers, the use of RPE had a significant impact on the relationship between blood biomarkers and Cr(VI) in inhalable and respirable dust. Low correlations between P-Cr and RBC-Cr may reflect a difference in kinetics.This study showed that Cr-blood-based biomarkers can provide information on how workplace exposure translates into systemic availability of Cr(III) (extracellular, P-Cr) and Cr(VI) (intracellular, RBC-Cr). Further studies are needed to fully appreciate their use in an occupational health and safety context