HAL du Programme national de recherche environnement-santé-travail (PNR EST)
Not a member yet
917 research outputs found
Sort by
No evidence for behavioral or physiological effects of nanoplastics ingestion in the fruit fly Drosophila melanogaster
No full textInternational audiencePlastic pollution increases worldwide, releasing small plastic particles into the environment, such as nanoplastics (NP) that affect living organisms. NP can penetrate biological membranes and interact with cellular components such as mitochondria. However, the effects of NP on terrestrial insects, the most diverse and abundant taxa, remains poorly studied compared to aquatic species. Our study assesses the effect of nanoplastics on the emergence rate, mitochondrial activity, metabolism, body mass, and locomotor activity in Drosophila melanogaster (Meigen, 1830, Diptera: Drosophilidae), a terrestrial insect. Three experimental groups were compared: a control group (C) with flies fed food without NP, a low contamination group (LOW) with flies fed food containing 1 mu g/g of NP of different sizes (20, 80 and 200 nm), and a high contamination group (HIGH) with flies fed food containing 500 mu g/g of NP of the same classes of sizes. Low and High groups were exposed to polystyrene NP for their entire development cycle. NP ingestion did not affect the number of pupae and adults, emergence rate, mitochondrial activity, metabolism and body mass. The locomotor activity of the flies was also unaffected by ingestion of NP. These results, compared with those reported in the literature, showed that the effect of nano-plastics on living organisms might depend on the species and polymer nature. The absence of detectable effects on flies is positive for the ecology of the species, constantly exposed to plastic pollution. Further studies in this area are still needed to fully determine the effects of NP on Drosophila biology and behavior
Sulfamethazine biodegradation in sediments is driven by chronic exposure concentrations
No full textInternational audienceSulfonamide antibiotics like sulfamethazine (SMZ) can accumulate in river surface sediments and promote the development of sulfonamide-degrading microorganisms. However, it remains unclear whether the capacity of natural microbial communities to biodegrade sulfonamide is significantly stimulated above specific exposure thresholds. To investigate this, we performed a 47-day microcosm study in laboratory channels, exposing natural sediment communities to six SMZ concentrations (from C0 to C5) using an exponential dose–response design with a maximal nominal concentration of 10 mg.kg−1 DW. At the end of the experiment, 14C-SMZ mineralization kinetics revealed a strong microbial adaptation to SMZ biodegradation at the two highest concentrations tested. Indeed, percentage mineralization was about 50 % in treatment C4 and 62 % in treatment C5 but remained lower than 2 % in all other treatments (C0 to C3). The relative abundance of sadA genes increased in C4 and C5, suggesting sadA as a key functional gene controlling potential to biodegrade SMZ within the community. The adaptation to biodegradation of SMZ was associated with changes in microbial community structure, diversity and composition. Cyanobacteria and Bacteroidota were the phyla most negatively affected by treatments C4 and C5 whereas the relative abundance of Proteobacteria increased, suggesting that at least some of the bacteria involved in SMZ biodegradation belonged to this class. Changes in diversity and the increase in the biodegradation potential of SMZ had no influence on the community tolerance to this pharmaceutical, as assessed through short-term toxicity tests on β-glucosidase activity
Long-term effects of the herbicide glyphosate and its main metabolite (aminomethylphosphonic acid) on the growth, chlorophyll a and morphology of freshwater benthic diatoms
No full textInternational audienceAlthough glyphosate and its main degradation product, aminomethylphosphonic acid (AMPA), are frequently found in surface waters worldwide, their effects on surface waters’ ecological health remain difficult to identify. In this study we investigated the impact of these two compounds on freshwater benthic diatoms, a key biological compartment which has been rarely documented so far. Besides potential effects on growth and chlorophyll a, diatom morphology was also documented via the appearance of deformations but also more subtle, non-teratological changes. In a first experiment, the two common diatom species Nitzschia palea and Gomphonema gracile were exposed to a wide range of concentrations of glyphosate (0.41-84.27 mg/L) and AMPA (2.89-103.53 mg/L) in order to assess their effects on growth and physiology (chlorophyll a content) after 7 d of exposure. Our results show that both compounds inhibited diatom growth while chlorophyll a was not affected. Glyphosate was more toxic than AMPA for both species and N. palea was more sensitive than G. gracile regardless of the tested compound. In a second experiment, longer-term effects were assessed by exposing the diatom N. palea in semi-static conditions for 28 d to 4 concentrations including an environmental one (0.0035-4.77 mg/L of glyphosate and 0.16-41.79 mg/L of AMPA). In addition to growth and chlorophyll a, a machine-learning based methodology was developed in order to analyze individual diatom morphometric descriptors. At the highest tested concentration, both contaminants inhibited growth but also chlorophyll a content. Moreover, the tested compounds did not generate teratological forms, but AMPA favored longer and slimmer individuals while glyphosate restricted diatom morphology by eliminating intermediate sizes, creating two subpopulations with distinct morphologies, thus underlying the activation of different mechanisms at population level. Our results show that morphological features could prove useful to quantify on a routine basis in order to better document the subtle ecotoxicological effects of contaminants
Temporal and spatial dynamics of the invasion of river biofilms communities by antibiotic resistance
No full textInternational audienceBackground and objectives: The emergence and dissemination of antibiotic resistance lies on two pillars, the selection of resistant variants during therapy and the subsequent spread of resistant bacteria (ARB) and their resistance genes (ARGs)[1]. As both recipient of anthropic pollution and sources of exposure, river aquatic environments act as a transmission belt for the spread of ARB/ARG. However, understanding the invasion of ARB/ARGs in rivers remains complex considering the number of existing ARG determinants and the multiplicity of pollution sources. In this work we explored the invasion dynamics of ARB/ARGs in river biofilms from remote streams with well-identified anthropogenic pollution inputs. The reversibility of the invasion phenomenon and the role of the resident community were also investigated.Methods: Remote rivers from the Vosges Mountains (Northeastern France) were selected for lack of anthropic activity in their watershed heads. Epilithic biofilms (resident community) were sampled along of the river continuums and the sites of prime-exposure to ARB/ARGs were identified by high-throughput qPCR for 45 ARGs. Immerged artificial biofilm supports were used to determine the dynamics of invasion processes and its reversibility when biofilms were moved upstream of the pollution source. The structure of biofilm communities was characterized by 16S rRNA gene metabarcoding.Results: The analysis of ARG composition in biofilms collected along the continuum of selected rivers allows identifying the site of prime-exposure to anthropogenic pollution responsible for ARB/ARG invasion. Using artificial supports positioned upstream and downstream the pollution input, we showed that the biofilm community composition differed by less than 20% over a 5-week period and between sites. When biofilms formed upstream of the pollution source are transferred downstream and vice versa, we demonstrated that upstream biofilm communities are more dynamics than the downstream ones. However, both biofilm communities are equally dynamics in terms of ARG invasion and ARG depuration for biofilm re-positioned downstream and upstream the pollution source respectively. Conclusions: Depuration of ARB/ARGs from natural biofilms can occur relatively fast when the anthropogenic pressure cease, without any massive alteration of the microbial community structur
Metabolic characterization of seven bee pollens: molecular network, metabolite isolation and antioxidant assessment
No full textInternational audienceIn a changing world, bees are facing increasing stressful conditions, such as ozone and pollutant concentrations, and more events of higher temperatures [1–3]. In a project called BeeMed [4], Vanderplanck et al. (CEFE, Montpellier, France) suggested that bees may develop an auto-medication behaviour by selecting the species that may provide them the most beneficial pollen content, notably antioxidant metabolites.The objective of this study, part of the BeeMed project, was to characterize the metabolic content of bee pollens from five dominant species and two mix of species. A Featured-Based Molecular Network (FBMN) was realized after UHPLC-MS/MS analysis to underscore the occurence of species metabolites. Major metabolites from one-species dominant pollen were purified by Centrifugal Partition and preparative chromatography for further chemical characterization (1D and 2D NMR). Extracts and purified metabolites were assessed for their antioxidant properties using an online-antioxidant ABTS assay.Three main spectral families were detected in all bee pollens namely polyamines (ex: spermidines, spermines), flavonoid glycosides and amino-acids. Specific benzylisoquinoline alkaloids (ex: scoulerin and derivatives) were exclusively detected in one-species dominant pollen."Isorhamnetin-like" dihexoside, exerting antioxidant properties, and "isorhamnetin-like" hexoside were purified from pollen and structurally confirmed. Myricetin dihexoside and p-coumaroyl dicaffeoyl spermidine isomers demonstrated the best antioxidant properties.The use of three complementary approaches (MS-based FBMN, metabolite purification and anti-oxydant assay) permitted to better describe pollen chemical diversity and pave the way for further experiments to better understand bee resilience facing oxidative stresses
Effects of household cleaning products on the lungs: an update
No full textInternational audienceIntroduction: Household disinfectants and cleaning products (HDCPs), which involve a complex mixture of chemical ingredients, are commonly used in homes. HDCPs significantly contribute to chemical exposure in the indoor environment by releasing particles and volatile organic compounds while being used, potentially harming the respiratory health of those exposed.Areas covered: We provide an overview of scientific literature, especially from the last five years, regarding the (i) effects of using of HDCPs on adults' respiratory health; (ii) associations between prenatal or childhood exposure to HDCPs and children respiratory health. Finally, we discuss on standard and innovative methods of HDCP exposure assessment.Expert opinion: Recent literature provides further evidence on the harmful role of HDCPs on respiratory health in both adults and children. Exposure to HDCPs is a modifiable asthma risk factor that requires more consideration, in order to reduce asthma-related morbidity, and to improve and maintain an optimal control of the disease. Further research is essential to deepen the current knowledge, particularly by using innovative methods of exposure assessment to HDCPs, which could enhance the exposure characterization in both adults and children, and contribute to identify HDCP's chemical compounds leading to a risk for respiratory health
Exploring heat risk in pregnant women: do environmental and social inequalities amplify heat exposure?
No full textInternational audienceHeat exposure in pregnancy has been associated with mother-child health. However, characterization of exposure to heat in pregnant women and its associated factors, such as air pollution, vegetation or social stressors, is lacking. We aimed to describe heat exposure according to air pollution and vegetation co-exposures, individual social position and socio-economic context of residence among French pregnant women. We studied 12,235 pregnant women from four mother-child cohorts. Exposure to heat (intensity, duration, severity), particulate matter, nitrogen dioxide (NO2), ozone (O3), and vegetation during summer were estimated at the women's residences. Socio-economic context of residence was assessed using the European Deprivation Index (EDI). Cumulative overexposure to heat, air pollution and vegetation were estimated according to reference values. Three profiles of heat exposure, multi-exposure and individual social position, were created using multivariate analysis and unsupervised clustering. Associations of the profiles of heat exposure and multi-exposure with air pollution, vegetation, individual social position and EDI were described using Wilcoxon tests and polytomous regressions. About one-third of pregnant women had a high heat exposure profile combining intense, severe and durable exposure. Depending on the location and year of pregnancy, 27-88% of women were overexposed to heat, air pollution and lack of vegetation. The relationships between profiles of heat and multi-exposure with air pollution, vegetation and individual social position and socioeconomic context of residence depended on the geographical and temporal context. No clear differential exposure pattern across social strata was found. Co-exposure to heat, air pollution and lack of vegetation is common among French pregnant women. Protective measures against summer heat would apply to all pregnant women, as heat exposure represents a universal risk, regardless of socioeconomic status. This research supports future epidemiological studies on combined effects of heat and co-exposures on pregnancy outcomes
Could electrohypersensitivity be a specific form of high sensory processing sensitivity?
No full textInternational audienceIntroduction Electrohypersensitivity (EHS) refers to a syndrome in which individuals claim to suffer from a variety of symptoms that they attribute to electromagnetic fields. The characteristics of this specific hypersensitivity, particularly in terms of symptoms, are similar to those associated with high sensory processing sensitivity (HSPS). This article raises the question of the superposition of these two types of sensitivity and investigates the existence of a link between the two. Methods Participants ( n = 100) completed a questionnaire measuring EHS and HSPS, as well as absorption, risk perception and avoidance strategies related to electromagnetic fields, and anxiety and depressive disorders. Results They showed an overrepresentation of highly sensitive people within the electrohypersensitive group. Furthermore, the results showed differences in terms of anxiety-depressive symptomatology and cognitive strategies (risk perception and avoidance strategies). Discussion The article discusses these results in the light of the literature and suggests avenues for future research and ways to help highly sensitive people, whether wor not this condition is considered to be caused by electromagnetic radiation
A Western-style diet shapes the gut and liver responses to low-dose, fit-for-purpose polystyrene nanoplastics in mice
No full textInternational audienceNanoplastics (NPLs) are an emerging global health concern, yet their toxicological impact remains uncertain, particularly among at-risk populations who are more susceptible to environmental stressors. While research on NPLs is expanding, most studies use commercial particles containing chemical additives, making it difficult to distinguish the effects of the polymer itself in its particulate form from those of confounding substances. In this study, we investigated the toxicity of fit-for-purpose, gold-labelled polystyrene NPLs (PS-NPLs; ∼600 nm) in mice exposed via drinking water at literature-informed doses (0.1, 1, and 10 mg kg -1 per day) for 90 days, under either chow diet (CD) or Western diet (WD) conditions. Using ICP-MS, PS-NPLs were detected and quantified in intestinal contents. Moreover, low-dose exposure (0.1 or 1 mg kg -1 per day, depending on diet and endpoint considered) resulted in increased body weight gain, altered mucus quality (i.e. shift in mucin O-glycan profiles), and subtle impairment of gut barrier integrity in a diet-dependent manner. Low-dose exposure also altered the gut microbiota composition in both diet groups, with diet-specific profiles, and shifted caecal metabolomic signatures only in CD-fed mice. Metabolically, low-dose PS-NPL exposure exacerbated glucose intolerance in WD-fed mice and promoted hepatic lipid accumulation and a shift in droplet size, regardless of diet. Overall, these findings demonstrate that PS-NPLs, in their particulate form and in the absence of confounding additives, can induce non-monotonic, diet-modulated effects on the gut and liver. This highlights the importance of considering particle behaviour in complex biological environments and including both healthy and at-risk populations in NPL toxicity assessments
