The aim of this study was to determine the amount, composition and origin of plastic debris in one of the world largest river, the Paraná River in Argentina (South America), focusing on the impact of urban rivers, relationships among macro, meso and microplastic, socio-political issues and microplastic ingestion by fish.We recorded a huge concentration of macroplastic debris of domestic origin (up to 5.05 macroplastic items per m2) dominated largely by bags (mainly high- and low-density polyethylene), foodwrapper (polypropylene and polystyrene), foam plastics (expanded polystyrene) and beverage bottles (polyethylene terephthalate), particularly downstream from the confluence with an urban stream. This suggests inadequate waste collection, processing and final disposal in the region, which is regrettably recurrent in many cities of the Global South and Argentina in particular.We found an average of 4654 microplastic fragments m−2 in shoreline sediments of the river, ranging from 131 to 12687 microplastics m−2. In contrast to other studies from industrialized countries from Europe and North America, secondary microplastics (resulting from comminution of larger particles) were more abundant than primary ones (microbeads to cosmetics or pellets to the industry). This could be explained by differences in consumer habits and industrialization level between societies and economies.Microplastic particles (mostly fibres) were recorded in the digestive tract of 100% of the studied Prochilodus lineatus (commercial species).Contrary to recently published statements by other researchers, our results suggest neither macroplastic nor mesoplastics would serve as surrogate for microplastic items in pollution surveys, suggesting the need to consider all three size categories.The massive plastic pollution found in the Paraná River is caused by an inadequate waste management. New actions are required to properly manage waste from its inception to its final disposal.

In the present study Mytilus galloprovincialis mussels were exposed for 28 days to three salinities: 30 (control), 25 and 35. Simultaneously, organisms at each salinity were exposed to either the antimicrobial agent Triclosan (TCS) or the pharmaceutical drug Diclofenac (DIC) at 1 μg/L. Salinity alone and exposure to PPCPs changed mussel's metabolic capacity and oxidative status, but no additive or synergetic effects resulting from the combined exposures were observed. Overall, the metabolic capacity of mussels was decreased when exposed to TCS and DIC under control salinity, which was less pronounced at salinities out of the control level. TCS had a notorious effect over glutathione peroxidase activity while DIC exposure enhanced catalase response. Such defence mechanisms were able to prevent cellular damage but still a clear reduction in GSH/GSSG ratio after PPCPs exposures indicates oxidative stress which could compromise bivalve's performance to further stressing events.

Due to the growing concern about the presence of microplastics (MP) in the environment, the number of studies evaluating the toxicity of these small persistent particles on different marine species has increased in recent years. Few studies have addressed their impact on marine phytoplankton, a subject of great concern since they are primary producers of the aquatic food web. The aim of this study is to unravel the cytotoxicity of 2.5 μg mL⁻¹ unlabelled amino-modified polystyrene beads of different sizes (0.5 and 2 μm) on the marine diatom Chaetoceros neogracile. In addition to traditional growth and photosynthesis endpoints, several physiological and biochemical parameters were monitored every 24 h in C. neogracile cells by flow cytometry during their exponential growth (72 h). Dynamic Light Scattering measurements revealed the strong aggregation and the negative charge of the beads assayed in the culture medium, which seemed to minimize particle interaction with cells and potentially associated impacts. Indeed, MP were not attached to the microalgal cell wall, as evidenced by scanning electron micrographs. Cell growth, morphology, photosynthesis, reactive oxygen species levels and membrane potential remained unaltered. However, exposure to MP significantly decreased the cellular esterase activity and the neutral lipid content. Microalgal oil bodies could serve as an energy source for maintaining a healthy cellular status. Thus, MP-exposed cells modulate their energy metabolism to properly acclimate to the stress conditions.

The consequences of indoor and outdoor air pollution on human health are of great concern nowadays. In this study, we firstly evaluated indoor and outdoor air pollution levels (CO, CO₂, NO, NO₂, PM₁₀) at an urban site in Dakar city center and at a rural site. Then, the individual exposure levels to selected pollutants and the variations in the levels of biomarkers of exposure were investigated in different groups of persons (bus drivers, traders working along the main roads and housemaids). Benzene exposure levels were higher for housemaids than for bus drivers and traders. High indoor exposure to benzene is probably due to cooking habits (cooking with charcoal), local practices (burning of incense), the use of cleaning products or solvent products which are important emitters of this compound. These results are confirmed by the values of S-PMA, which were higher in housemaids group compared to the others. Urinary 1-HOP levels were significantly higher for urban site housemaids compared to semirural district ones.Moreover, urinary levels of DNA oxidative stress damage (8-OHdG) and inflammatory (interleukin-6 and -8) biomarkers were higher in urban subjects in comparison to rural ones.The air quality measurement campaign showed that the bus interior was more polluted with PM₁₀, CO, CO₂ and NO than the market and urban or rural households. However, the interior of households showed higher concentration of VOCs than outdoor sites confirming previous observations of higher indoor individual exposure level to specific classes of pollutants.

Nanotechnology and use of nanomaterials (NMs) improve life quality, economic growth and environmental health. However, the increasing production and use of NMs in commercial products has led to concerns about their potential toxicity on human and environment health, as well as its toxicological classification and regulation. In this context, there is an urgent need to standardize and validate procedures for nanotoxicity testing. Since the zebrafish embryotoxicity test (ZET) has been indicated as a suitable approach for the toxicity assessment of traditional and emergent pollutants, the aim of this review is to summarize the existing literature on embryotoxic and teratogenic effects of NMs on zebrafish. In addition, morphological changes in zebrafish embryos induced by NMs were classified in four reaction models, allowing classification of the mode of action and toxicity of different types of NM. Revised data showed that the interaction and bioaccumulation of NMs on zebrafish embryos were associated to several toxic effects, while the detoxification process was limited. In general, NMs induced delayed hatching, circulatory changes, pigmentation and tegumentary alterations, musculoskeletal disorders and yolk sac alterations on zebrafish embryos. Recommendations for nanotoxicological tests are given, including guidance for future research. This review reinforces the use of the ZET as a suitable approach to assess the health risks of NM exposure.

BADGE (bisphenol A diglycidyl ether) is a synthesis product of bisphenol A (BPA), which, like other plasticizers, can cross the human placenta and reach the foetus. However, compared to BPA, there is almost no toxicological information. This work investigates the toxicity, endocrine and lipid disruption potential of BADGE and its hydrolysed and chlorinated derivatives (BADGE·H₂O and BADGE·2HCl) in human placental JEG-3 cells. The analysis of culture medium by HPLC-ESI(+)-QqQ evidenced a good bioavailability of BADGE·2HCl and BADGE·H₂O, but low stability of BADGE. Regardless, BADGE·2HCl and BADGE showed higher cytotoxicity than BADGE·H₂O, which was the only compound that significantly inhibited CYP19 activity (IC₅₀ 49 ± 5 μM). JEG-3 cells lipidome analyzed by FIA-ESI(+/−)-Orbitrap was significantly altered by exposure to BADGE·2HCl and BADGE at concentrations at the low μM range. BADGE·2HCl lead to a strong decrease of diacyl- and triacyl-glycerides (DGs,TGs) together with some membrane lipids, while BADGE lead to an accumulation of TGs. The results evidence the ability of BADGE and derivatives to affect placental lipid handling and to modulate placental CYP19 activity (BADGE·H₂O) and highlights the need to monitor human exposure to these compounds, at least as intensely as BPA is monitored.

International audience | Several human activities such as mining, smelting, or transportations lead to trace metal pollution in soil. The presence of these pollutants can represent environmental and organism health risks. Phytoextraction can be used to remediate trace metal-contaminated soils. It uses the plants' ability to remove trace metals from soil and to accumulate them in their shoots, which can then be harvested. We studied the spontaneous vegetation growing on a brownfield located in France. The use of native plants is interesting since spontaneous vegetation is already well adapted to the site's environmental conditions leading to a better survival and growth than non-native plants. Ten native plant species were sampled, and the Cr, Cu, Cd, Ni, Pb, and Zn concentrations present in their shoots were measured. In order to determine the plant's capacity to extract trace metals from the soil, the bioconcentration factor (BCF) was calculated for each plant and trace metal. Plants with a BCF greater than 1 are able to accumulate trace metals in their shoots and could be a good candidate to be used in phytoextraction. Results underscored one new accumulator plant for Zn, Tussilago farfara L., with a BCF value of 3.069. No hyperaccumulator was found among the other sampled plants. Our preliminary study showed that T. farfara is able to accumulate zinc in its shoots. Moreover, this native plant is a pioneer species able to quickly colonize various habitats by vegetative multiplication. That is why T. farfara L. could be interesting for zinc phytoextraction and could be worth further studies.

Microplastic pollution has received considerable attention in marine systems, but recent work shows substantial plastic pollution also occurs in freshwater ecosystems. Most freshwater research has focused on large rivers and lakes, but small streams are the primary interface between land, where plastic is used, and drainage networks. We examined variation in the amount and form of plastic occurring in small streams spanning an urbanisation gradient. All streams contained microplastics with concentrations similar to that found in larger systems (up to 303 particles m−3 in water and 80 particles kg−1 in sediment). The most abundant types were fragments and small particles (63–500 μm). Chemical types of plastic were quite variable and often not predictable based on size, form and colour. Variation in microplastic abundance across streams was high, but only partially explained by catchment scale parameters. There was no relationship between human population density or combined stormwater overflows and microplastic abundance. Residential land cover was related to microplastic abundance, but explanatory power was low. Our results suggest local-scale factors may be more important than catchment-scale processes in determining microplastic pollution in small streams.