The present study, conducted in the Galion Bay in Martinique, aims to highlight the temporal and seasonal variations of chlordecone contamination (an organochlorine pollutant) in the ambient environment (seawater) and also in the marine organisms in three main coastal marine habitats (mangroves, seagrass beds and coral reefs). To this end, two methodologies were used to measure and compare the chemical contamination of seawater during 13 months (spot samplings and POCIS technique). In parallel, concentrations of chlordecone and isotopic ratios (C and N) were carried out on marine organisms, collected during two contrasting climatic periods (dry and rainy), to evidence seasonal variations. The results showed that the contamination of seawater displayed significant variations over time and depended on environmental factors such as water flows, which imply dilution and dispersion phenomena. Concerning the marine organisms, the level of contamination varied considerably between the two seasons in seagrass beds with higher levels of contamination during the rainy season. Reef organisms were more moderately affected by this pollution, while mangrove organisms showed a high level of chlordecone whatever the season. Finally, isotope analyses highlighted that bioamplification along marine food webs occurs at each season and each station.

The EcotoxicoMicYR group was initially composed of 4 Ph.D. students and 4 post-doctoral researchers. In brief, the EcotoxicoMicYR webinar took place three Monday afternoons in a row from November 22 to December 6, 2021. These three half-day webinars reached a success beyond our expectations with 25 countries and 41 presentations. Keynote lectures were delivered by Dr Fabio Roldan (Pontificia Universidad Javeriana, Colombia), Dr Belinda Ferrari (The University of New South Wales, Australia), and Dr Ahmed Tlili (Eawag, Switzerland). Their presentations provided an insight on latest research developments in the microbial ecotoxicology field and highlighted their specific contribution to this discipline. Twenty-two oral presentations and 16 pre-recorded presentations were diffused.

Plastic and microplastic pollutions are known to be widespread across the planet in all types of environments. However, relatively little about microplastic quantities in the deeper areas of the oceans is known, due to the difficulty to reach these environments. In this work, we present an investigation of microplastic (<5 mm) distribution performed in the bottom sediments of the abyssal plain off the coast and the canyon of Toulon (France). Four samples of deep-sea sediment were collected at the depth of 2443 m during the sea operations carried out by the French oceanographic cruises for the KM3NeT project. The chemical and physical characterisation of the sediment was carried out, and items were extracted from sediments by density separation and analysed by optical microscope and µRaman spectroscopy. Results show microplastics in the deep-sea sediments with a concentration of about 80 particles L−1, confirming the hypothesis of microplastics spread to abyssal sediments in the Mediterranean Sea.

Regulatory assessment of the effects of chemicals requires the availability of validated tests representing different environments and organisms. In this context, developing new tests is particularly needed for marine species from temperate environments. It is also important to evaluate effects that are generally poorly characterized and seldom included in regulatory tests. In this study, we designed an exposure protocol using European sea bass (Dicentrarchus labrax) larvae. We examined classical toxicological values (LCx) as well as behavioral responses. By comparing different hatching and breeding strategies, we defined the optimal conditions of exposure as non-agitated conditions in 24- or 48-well microplates. Our exposure protocol was then tested with 3,4-dichloroaniline (3,4-DCA), a recommended reference molecule. Based on our results, the 96 h LC50 for 3,4-DCA corresponded to 2.04 mg/L while the 168 h LC50 to 0.79 mg/L. Behavioral analyses showed no effect of 3,4-DCA at low concentration (0.25 mg/L). In conclusion, the present work established the basis for a new test which includes behavioral analysis and shows that the use of sea bass is suitable to early-life stage toxicity tests.

Sleep is a crucial aspect of the human daily life since it allows us to recover from physical and psychological fatigue and its lack can bring several consequences to human health. People spend around one third of their life sleeping but, despite that, their exposure to pollutants during sleep is often neglected. Specifically, students typically change their habits after entering university, due to the freedom that they are allowed at this stage of their lives. These habits often include their sleep patterns, which not only affects their health, but their academic performance as well. This study aimed to assess the indoor air quality (IAQ) that university students are exposed to in their sleeping environment and how it affects their sleep quality. Firstly, an online survey, based in standardized questionnaires, was conducted to a sample of 1040 individuals to characterize sleep habits and, ultimately, to provide an overview of the sleep quality of the Portuguese population. Students were one of the population groups that showed worse results: only 31% had good sleep quality and only 62% showed good sleep health. Afterwards, a study to assess sleep quality (by actigraphy and standardized questionnaires) and IAQ (by a monitoring unit based in low-cost sensors) during the sleeping period of two consecutive nights of 13 students in Lisbon university dorms was conducted. Mean levels of CO₂ and VOCs above the established legislation were found during sleep, indicating that ventilation conditions were not sufficient to keep an acceptable IAQ. Temperature was also out of the acceptable comfort range during 44% of the sleeping time. The perceived sleep quality of students was found to be negatively associated with the number of awakenings and the mean levels of carbon dioxide and relative humidity during the sleeping period. These results confirm previous findings where some IAQ parameters may influence the sleep quality of the individuals, highlighting the importance to focus on the IAQ of sleeping environments as a strategy to improve sleep quality of individuals.

This study presents a method for “downscaling” aggregated global emissions of CO, NOₓ, and PM₂.₅ based on georeferenced information (spatial proxies). We distribute ECLIPSE-CLE emissions for Quito, Ecuador, in 2015 and 2017. The study area is a grid of 0.5 × 0.5 km² cells over a 110 × 110 km² area. The emission sectors (proxies in parenthesis) are agricultural (land-use maps), domestic (land-use and population density), energy, industry, and waste disposal (point source location from local inventory), and transport (population, vehicle traffic, and road density). Emission distribution quality is satisfactorily evaluated (graphically and statistically) by implementing them in the UBM model and comparing modeled concentrations with observations. This study also explores an alternative proxy set-up for main road emissions based on road density, which, for some modeling sites, results in a better agreement with the observations. Finally, this methodology is applied for comparing air pollution due to two urban growth types for Quito in 2040: sprawl and densification. Both scenarios lead to lower concentrations than in 2017, except for O₃. Although the two scenarios attain similar concentrations, urban sprawl presents, in general, noticeably higher values for NOₓ and NO₂.

Air pollutants influence the morphological, physiological, and biochemical status of plants, and their impacts vary substantially among different species and cultivars. Current review synthesises published literature on the assessment of air pollution impacts on vegetation, with a specific focus on chronicling and summarizing scientific methods that quantify those impacts. Investigations carried out globally on pollutant-plant exposure-response, and articles that describe impact of air pollutants on plants and pollutant abatement using green infrastructure (GI) were systematically reviewed. 273 articles reviewed indicated that a substantial number of past explorations were on a small spectrum of certain species, mainly wheat, rice, soybean and maize; and fewer on non-crop plant species, which cover most of the urban areas and are part of GI. Furthermore, in lower middle-income countries which face significant pollution loads, even studies on crop species are limited. Most studies either use Air Pollution Tolerance Index, which is not pollutant dependent or concentrate on either Ozone or Particulate Matter (PM) and rarely investigate the impact of multiple pollutants in the atmosphere. Also, very few studies differentiate the effect of PM on plants based on its composition. Subsequently, the best possible experimental set ups and wide array of plant health parameters for determining and understanding the effects of different air pollutants on a variety of plant species has been emphasized. While this review compiled literature-based commendations for academic federations wanting to study and quantify air pollutant impacts on vegetation, numerous pertinent vital topics for future research were identified.

Countries in Northeast Asia have been regulating PM₂.₅ sources and studying their local and transboundary origins since PM₂.₅ causes severe impacts on public health and economic losses. However, the separation of local and transboundary impacts is not fully realized because it is impossible to change air pollutant emissions from multiple countries experimentally. Exceptionally, the early stage of the COVID-19 outbreak (January–March 2020) provided a cross-country experiment to separate each impact of PM₂.₅ sources identified in Seoul, a downwind area of China. We evaluated the contributions of PM₂.₅ sources compared to 2019 using dispersion normalized positive matrix factorization (DN-PMF) during three meteorological episodes. Episodes 1 and 2 revealed transboundary impacts and were related to reduced anthropogenic emissions and accumulated primary pollutants in Northeast China. Anthropogenic emissions, except for the residential sector, decreased, but primary air pollutants accumulated by residential coal combustion enhanced secondary aerosol formation. Thus, the contributions of sulfate and secondary nitrate increased in Seoul during episode 1 but then decreased maximally with other primary sources (biomass burning, district heating and incineration, industrial sources, and oil combustion) during episode 2 under meteorological conditions favorable to long-range transport. Local impact was demonstrated by atmospheric stagnation during episode 3. Meteorological condition unfavorable to local dispersion elevated the contributions of mobile and coal combustion and further contributed to PM₂.₅ high concentration events (HCE). Our study separates the local and transboundary impacts and highlights that cooperations in Northeast Asia on secondary aerosol formation and management of local sources are necessary.

Understanding and quantifying the influence of volatile organic compounds (VOCs) on ozone and secondary organic aerosol formation is essential for better prediction/estimation of these products. A total of 9 VOCs along with surface ozone were measured during the year 2019 at Pune (India) location. The ozone formation potential (OFP) and secondary organic aerosol formation potential (SOAFP) estimations are compared for 2 methods-using measured VOC concentrations and using their photochemical initial concentrations (PIC). The OFP and SOAFP estimated based on the measured VOC concentrations provide an incomplete understanding of these 2 formation processes. This is mainly because measured VOCs don't account for the photochemical losses that compounds undergo from the source to the receptor. The PIC values of VOCs have been estimated in this study to highlight the importance of considering the photochemical losses. For example, the PIC value of highly reactive compound, isoprene, was found to be 152% higher (1.48 ppbv) than its measured value (0.59 ppbv). The resultant total OFP estimate based on PIC values of all the VOCs was found to be 53.30 ± 35.02 ppbv as compared to 45.99 ± 29.35 ppbv obtained from measured VOCs. Based on k-means clustering analysis, it was found that the highest ozone formation was favored under transition regime chemistry when PIC values were considered. The average total SOAFP based on PIC values was found to be 1.32 ± 1.40 ppbv, while it was 1.17 ± 1.18 ppbv for measured VOCs. The aromatics contributed to over 90% of total SOAFP estimated for the region.