Unveiling the presence of endocrine disrupting chemicals in northern French soils: Land cover variability and implications.

Endocrine disrupting chemicals (EDCs) are chemicals that can be found in the environment and have adverse effects on human health by mimicking, perturbing and blocking the function of hormones. They are commonly studied in water surfaces, rarely in soils, although it can be an important source of their presence in the environment. Their detection in soils is analytically challenging to quantify, hence the lack of known background concentrations found in the literature. This scientific research aimed to detect EDCs in soils by analyzing 240 soil samples using an optimized protocol of double extraction and analysis using liquid chromatography coupled to mass spectrometry. The optimized protocol allowed for very sensitive detection of the targeted compounds. The results showed a high concentration of 29.391 ng/g of 17ß-estradiol in soils and 47.16 ng/g for 17α-ethinylestradiol. Testosterone and Progesterone were detected at a highest of 1.02 and 6.58 ng/g, respectively. The ∑EDCs which included estrogens, progesterone, testosterone and Bisphenol A was found at an average of 22.72 ± 35.46 ng/g in the study area. The results of this campaign showed a heterogeneous geographic distribution of the EDCs compounds in the different zones of study. Additionally, the study conducted a comparison of the concentration of EDCs in different land covers including urban areas, agricultural lands, grasslands and forests. We observed a significant difference between forests and other land covers (p < 0.0001) for 17α-ethinylestradiol, estriol, and progesterone. This presence of EDCs in forest lands is not yet understood and requires further studies concerning its origins, its fate and its effect on human health. This study is the first large-scale sampling campaign targeting EDCs in soils in Europe and the second in the world. It is also the first to assess the concentrations of these compounds based on different land covers.

Combined toxic effects and DNA damage to two plant species exposed to binary metal mixtures (Cd/Pb).

Acute and long-term (3-, 10- and 56-day exposure) laboratory toxicity tests were carried out to assess the individual and combined toxic effects of cadmium (Cd) and lead (Pb) in Brassica oleracea and Trifolium repens. In addition to morphological parameters, this work also used comet assay to address endpoints in relation to genotoxicity. Bioaccumulation was measured to demonstrate the influence of the mixture on the concentrations of each metal in the plant. The statistical method reported by Ince et al. (1999) was used to evaluate the types of interaction between Cd and Pb in each treatment and concerning their combined effect. This study concludes that the combined effects of binary metal combinations of Cd/Pb on morphological parameters are most often additive, sometimes antagonistic and more rarely synergistic, thus extending the findings of previous publications on this subject. DNA damage analysis revealed concentration- and time-dependent interactions. Synergistic effects of mixed metals (more breaks than individually applied metals) are observed in T. repens after a short exposure. Antagonistic effects are statistically significant after 10 days-exposure, suggesting competition between metals. At 56 days, the rate of DNA damage observed in plants exposed to the Cd/Pb mixture was similar to that measured in plants exposed to lead only and was significantly lower than the rate of DNA damage induced by Cd. This supports the idea that there may be competition between metals and also strengthens the hypothesis that long-term reparation mechanisms may be implemented. Cd/Pb co-exposure does not significantly influence the bioaccumulation of each metal. It is nevertheless important to note that a statistically significant 'interaction' is not necessarily biologically relevant and should therefore be considered with caution when assessing heavy metals combined effects.

Combined effect of Cd and Pb spiked field soils on bioaccumulation, DNA damage, and peroxidase activities in Trifolium repens.

The present study was designed to investigate the combined effects of Cd and Pb on accumulation and genotoxic potential in white clover (Trifolium repens). For this purpose, T. repens was exposed to contaminated soils (2.5-20 mg kg(-1) cadmium (Cd), 250-2000 mg kg(-1) lead (Pb) and a mixture of these two heavy metals) for 3, 10 and 56 days. The resulting bioaccumulation of Cd and Pb, DNA damage (comet assay) and peroxidase activities (APOX and GPOX) were determined. The exposure time is a determinant factor in experiments designed to measure the influence of heavy metal contamination. The accumulation of Cd or Pb resulting from exposure to the two-metal mixture does not appear to depend significantly on whether the white clover is exposed to soil containing one heavy metal or both. However, when T. repens is exposed to a Cd/Pb mixture, the percentage of DNA damage is lower than when the plant is exposed to monometallic Cd. DNA damage is close to that observed in the case of monometallic Pb exposure. Peroxidase activity cannot be associated with DNA damage under these experimental conditions.

Antioxidant defense gene analysis in Brassica oleracea and Trifolium repens exposed to Cd and/or Pb.

This study focused on the expression analysis of antioxidant defense genes in Brassica oleracea and in Trifolium repens. Plants were exposed for 3, 10, and 56 days in microcosms to a field-collected suburban soil spiked by low concentrations of cadmium and/or lead. In both species, metal accumulations and expression levels of genes encoding proteins involved and/or related to antioxidant defense systems (glutathione transferases, peroxidases, catalases, metallothioneins) were quantified in leaves in order to better understand the detoxification processes involved following exposure to metals. It appeared that strongest gene expression variations in T. repens were observed when plants are exposed to Cd (metallothionein and ascorbate peroxidase upregulations) whereas strongest variations in B. oleracea were observed in case of Cd/Pb co-exposures (metallothionein, glutathione transferase, and peroxidase upregulations). Results also suggest that there is a benefit to use complementary species in order to better apprehend the biological effects in ecotoxicology.

Antioxidant responses of Annelids, Brassicaceae and Fabaceae to pollutants: a review.

Pollutants, such as Metal Trace Elements (MTEs) and organic compounds (polycyclic aromatic hydrocarbons, pesticides), can impact DNA structure of living organisms and thus generate damage. For instance, cadmium is a well-known genotoxic and mechanisms explaining its clastogenicity are mainly indirect: inhibition of DNA repair mechanisms and/or induction of Reactive Oxygen Species (ROS). Animal or vegetal cells use antioxidant defense systems to protect themselves against ROS produced during oxidative stress. Because tolerance of organisms depends, at least partially, on their ability to cope with ROS, the mechanisms of production and management of ROS were investigated a lot in Ecotoxicology as markers of biotic and abiotic stress. This was mainly done through the measurement of enzyme activities The present Review focuses on 3 test species living in close contact with soil that are often used in soil ecotoxicology: the worm Eisenia fetida, and two plant species, Trifolium repens (white clover) and Brassica oleracea (cabbage). E. fetida is a soil-dwelling organism commonly used for biomonitoring. T. repens is a symbiotic plant species which forms root nodule with soil bacteria, while B. oleracea is a non-symbiotic plant. In literature, some oxidative stress enzyme activities have already been measured in those species but such analyses do not allow distinction between individual enzyme involvements in oxidative stress. Gene expression studies would allow this distinction at the transcriptomic level. A literature review and a data search in molecular database were carried out on the basis of keywords in Scopus, in PubMed and in Genbank™ for each species. Molecular data regarding E. fetida were already available in databases, but a lack of data regarding oxidative stress related genes was observed for T. repens and B. oleracea. By exploiting the conservation observed between species and using molecular biology techniques, we partially cloned missing candidates involved in oxidative stress and in metal detoxification in E. fetida, T. repens and B. oleracea.

[Air pollution biomonitoring with plants and fungi: concepts and uses]. / La biosurveillance végétale et fongique de la pollution atmosphérique : concepts et applications.

Air pollution remains a major environmental concern of the French. Since about 30 years, due to evolution and diversification of sources, pollution became more and more complex, constituting a true "cocktail". Today, it is very important to know environmental and health effects of this cocktail. In this context air biomonitoring using plants and fungi can bring a lot of information. Biomonitoring includes four concepts: the use of biomarkers, bioindication biointegration and bioaccumulation. These four concepts are articulated according to the levels of biological organization, what links up biosurveillance on fundamental plan with ecotoxicology. It is a complementary approach of the physicochemical techniques of air pollution measurements. The main objectives of biomonitoring studies are the monitoring of the space and temporal distribution of pollutants effect; the monitoring of local sources; participation in the health risks assessment; the information of people and the help to decision in public policies. Biomonitoring of air quality is a method, which made its proof in numerous domains of application and brings fundamental information on the impacts of the quality of air. Recent evolution of low concerning biggest industries allows us to envisage the increase of air quality biomonitoring with plants and fungi applications in the field of the valuation of environmental and health risks. The recent normalization (French and European) of different methods will also allow the development of uses.

[Indoor air quality in schools]. / Qualité de l'air à l'intérieur des écoles.

Indoor air quality in schools has received particular attention over the past several years. Children are considered as one of the most sensitive groups to atmospheric pollution because their bodies are actively growing and they breathe higher volumes of air relative to their body weights than adults do. They also spend more time in school or group structures (preschools, day nurseries) than in any indoor environments other than the home. The analysis of children's exposure to air pollution at school requires the identification of the main pollutant sources present in these educational institutions. Both a strong contribution of outdoor pollution and a very specific pollution bound to school activities such as the use of paints, markers, glues, and manufactured ink eraser pens, exist. The ventilation in school buildings also plays an important role in air quality. A higher air exchange may improve thermal comfort and air quality. The cause of indoor air pollution is a combinatory effect of physical, chemical, and biological factors, and the adequacy of ventilation in the environment. Several pollutants have been reported to exist in classrooms such as bacteria, molds, volatile organic compounds, persistent organic pollutants and microparticles. There is a correlation between the concentrations of the pollutants and onset of health problems in schoolchildren. We observe predominantly respiratory symptoms as well as a prevalence of respiratory diseases such as asthma and allergies. This study shows that poor indoor air quality affects children's health.