Environments, Volume 8, Issue 4 (April 2021) – 12 articles

Microplastics (MPs) constitute a known, undesirable contaminant of the ecosystems. Land-based pollution is considered to be an important contributor, but microplastics in the terrestrial environment remains largely unquantified. Some agriculture practices, such as plastic mulch and compost application, are suspected to be major sources of microplastics as plastics are exposed to weathering or are present in organic fertilizers. The overall aim of this research is to bridge the terrestrial plastic contamination information gap, focusing on light density microplastics in two vegetable production systems in Southeast Spain and in the Netherlands. The selected farmer in Spain used plastic mulch for more than 12 years whereas the two farmers in the Netherlands annually applied 10 t ha⁻¹ compost for the past 7 and 20 years. Samples from two different depths were collected: 0–10 cm and 10–30 cm. High quality compost samples originating from municipal organic waste and from garden and greenhouse waste were obtained from two Dutch compost plants. All samples from both Spanish (n = 29) and Dutch (n = 40) soils were contaminated by microplastics, containing 2242 ± 984 MPs kg⁻¹ and 888 ± 500 MPs kg⁻¹, respectively. Compost samples from municipal organic waste (n = 9) were more contaminated than the ones from garden and green house wastes (n = 19), with, respectively, 2800 ± 616 MPs kg⁻¹ and 1253 ± 561 MPs kg⁻¹. These results highlight the need for studies focusing on the effects of microplastics in the environment and the need for monitoring campaigns and the implementation of thresholds to regulate the microplastic contamination. Full article

Bisphenol A (BPA) and bisphenol S (BPS) are environmental contaminants that have been associated with the development of insulin resistance and type 2 diabetes (T2D). Two organs that are often implicated in the development of insulin resistance are the skeletal muscle and the adipose tissue, however, seldom studies have investigated the effects of bisphenols on their metabolism. In this review we discuss metabolic perturbations that occur in both the skeletal muscle and adipose tissue affected with insulin resistance, and how exposure to BPA or BPS has been linked to these changes. Furthermore, we highlight the possible effects of BPA on the cross-talk between the skeletal muscle and adipose tissue. Full article

Marine macroalgae offers a promising third generation feedstock for the production of fuels and chemicals, avoiding competition with conventional agriculture and potentially helping to improve eutrophication in seas and oceans. However, an increasing amount of plastic is distributed into the oceans, and as such contaminating macroalgal beds. One of the major plastic contaminants is nylon 6 derived from discarded fishing gear, though an increasing amount of alternative nylon polymers, derived from fabrics, are also observed. This study aimed to assess the effect of these nylon contaminants on the hydrothermal liquefaction of Fucus serratus. The hydrothermal liquefaction (HTL) of macroalgae was undertaken at 350 °C for 10 min, with a range of nylon polymers (nylon 6, nylon 6/6, nylon 12 and nylon 6/12), in the blend of 5, 20 and 50 wt.% nylon to biomass; 17 wt.% biocrude was achieved from a 50% blend of nylon 6 with F. serratus. In addition, nylon 6 completely broke down in the system producing the monomer caprolactam. The suitability of converting fishing gear was further demonstrated by conversion of actual fishing line (nylon 6) with the macroalgae, producing an array of products. The alternative nylon polymer blends were less reactive, with only 54% of the nylon 6/6 breaking down under the HTL conditions, forming cyclopentanone which distributed into the biocrude phase. Nylon 6/12 and nylon 12 were even less reactive, and only traces of the monomer cyclododecanone were observed in the biocrude phase. This study demonstrates that while nylon 6 derived from fishing gear can be effectively integrated into a macroalgal biorefinery, alternative nylon polymers from other sectors are too stable to be converted under these conditions and present a real challenge to a macroalgal biorefinery. Full article

The diffusion of Coronavirus disease (COVID-19) impacted the whole world, changing the life habits of billions of people. These changes caused an abundant increase in personal protective equipment (PPE, e.g., masks and gloves) use by the general population, which can become a concerning issue of plastic pollution. This study aims to evaluate the negative effects of the abundant PPE use following the COVID-19 diffusion using the test site of the Lombardy region, an area highly affected by the pandemic. Population data were retrieved from national databases, and the COVID-19 national guidelines were considered to estimate the total use of PPEs during 2020. Then, the quantity of waste derived from their use was evaluated based on the weight of PPEs. As well, possible scenarios for 2021 were proposed based on 2020 estimations. The results suggested different negative effects of the diffusion of PPEs both on waste management and on the environment: The abundant increase in PPEs-derived waste caused an increase in terms of costs for management, and the potential direct spreading in the environment of these materials (especially masks) poses a serious threat for an increase in microplastics in water bodies. Following this evaluation, a careful choice regarding COVID-19 measures of containment should be performed especially by the general population, avoiding contagion diffusion and reducing the possible environmental impact derived from disposable PPE use. Full article

The management of large volumes of organic residues generated in different livestock, urban, agricultural and industrial activities is a topic of environmental and social interest. The high organic matter content of these residues means that their application as soil organic amendments in agriculture is considered one of the more sustainable options, as it could solve the problem of the accumulation of uncontrolled wastes while improving soil quality and avoiding its irreversible degradation. However, the behavior of pesticides applied to increase crop yields could be modified in the presence of these amendments in the soil. This review article addresses how the adsorption–desorption, dissipation and leaching of pesticides in soils is affected by different organic residues usually applied as organic amendments. Based on the results reported from laboratory studies, the influence on these processes has been evaluated of multiple factors related to organic residues (e.g., origin, nature, composition, rates, and incubation time of the amended soils), pesticides (e.g., with different use, structure, characteristics, and application method), and soils with different physicochemical properties. Future perspectives on this topic are also included for highlighting the need to extend these laboratory studies to field and modelling scale to better assess and predict pesticide fate in amended soil scenarios. Full article

Many governments have imposed the public use of face masks and they are now moving towards enforcing disposable masks to abate COVID-19 transmission. While disposable masks consistently provide higher protection, they also carry multiple environmental burdens, from greenhouse gases released during production to the landfilling and littering. Conversely, reusable masks’ protection can vary from >90% certified industrial masks, similar to disposable masks, to dubious homemade or artisanal masks. This work discusses the protection provided by different masks, their impact on the environment, and new proposals combining concerns about public health and sustainability. Full article

A reduction in the energy-related emissions of air pollutants would not only mitigate climate change but would also improve local air quality and public health. This paper aimed to analyze the trends of air quality index (AQI) and greenhouse gas (GHG) emissions in Taiwan by using the latest official statistics. In addition, this study also summarized regulatory measures for controlling air pollution from the energy sector with relevance to sustainable development goals (SDGs). With the joint efforts by the public and private sectors, the change in the total GHG emissions did not vary much with the exception of 2009, ranging from 250 to 272 million metric tons of CO₂ equivalent from 2005 through 2019. Based on the data on AQI, the percentage of AQI by station-day with AQI > 100 has decreased from 18.1% in 2017 to 10.1% in 2020, indicating a decreasing trend for all criteria air pollutants. On the other hand, the coronavirus disease (COVID-19) lockdown, in 2019, has positively impacted Taiwan’s urban air quality, which was consistent with those observed in other countries. This consistent situation could be attributed to the climate change mitigation policies and promotional actions under the revised Air Pollution Control Act and the Greenhouse Gas Reduction and Management Act of 2015. In response to the SDGs launched by the Taiwan government in 2018, achieving the relevant targets by 2030 can be prospective. Full article

Background: The aim of this preliminary study was to measure radon concentrations in a hospital in order to verify to what extent these concentrations depend on various environmental variables taken into consideration, and consequently to determine the urgency to implement mitigation actions. Methods: The rooms where the concentration of the gas was potentially highest were monitored. Investigators adopted a Continuous Radon Monitor testing device. Qualitative and normally distributed quantitative variables were summarised with absolute (relative) frequencies and means (standard deviations, SD), respectively. As regards environmental variables, the difference in radon concentrations was determined using the rank-based nonparametric Kruskal–Wallis H test and the Mann–Whitney U test. Results: All measurements, excluding the radiotherapy bunkers that showed high values due to irradiation of radiotherapy instruments, showed low radon levels, although there is currently no known safe level of radon exposure. In addition, high variability in radon concentration was found linked to various environmental and behavioural characteristics. Conclusions: The results on the variability of radon levels in hospital buildings highlighted the key role of monitoring activities on indoor air quality and, consequently, on the occupants’ health. Full article

Assessing the water quality by using biological indicators is a reliable and economically feasible way to promote environmental conservation in developing tropical countries. Here, we report one of the few examples of river biomonitoring in Honduras. In June 2005, benthic macroinvertebrates were collected from six sites in the Río Cangrejal basin. An adapted version of the Biological Monitoring Working Party index (BMWP) was used to assess the water quality because it is simple, consolidated, relatively easy to use, and needs a family-level identification. Moreover, two other community metrics were calculated, namely the total taxon richness and local contribution to beta diversity (LCBD). Differences in the biomonitoring and diversity metrics among sites and their correlations were statistically tested. Thirty-nine macroinvertebrate taxa were collected and, despite significant differences in the BMWP score, all sampling sites were classified in the high environmental quality class. A very strong and positive correlation between the BMPW and taxon richness was found, while LCBD did not vary significantly and did not correlate with the other metrics. Our results suggest that taxon richness could be used as a surrogate indicator to assess the water quality when consolidate biomonitoring methods are not available. Full article

Gas transport parameters such as gas diffusivity (D_p/D₀), air permeability (k_a), and their dependency on void space (air-filled porosity, ε) in a waste body govern convective air and gas diffusion at solid waste dumpsites and surface emission of various gases generated by microbial processes under aerobic and anaerobic decompositions. In this study, D_p/D₀(ε) and k_a(ε) were measured on dumping solid waste in Japan such as incinerated bottom ash and unburnable mixed waste as well as a buried waste sample (dumped for 20 years). Sieved samples with variable adjusted moistures were compacted by a standard proctor method and used for a series of laboratory tests for measuring compressibility, saturated hydraulic conductivity, and gas transport parameters. Results showed that incinerated bottom ash and unburnable mixed waste did not give the maximum dry density and optimum moisture content. Measured compressibility and saturated hydraulic conductivity of tested samples varied widely depending on the types of materials. Based on the previously proposed D_p/D₀(ε) models, the diffusion-based tortuosity (T) was analyzed and unique power functional relations were found in T(ε) and could contribute to evaluating the gas diffusion process in the waste body compacted at different moisture conditions. Full article

The reintroduction of the extinct beluga sturgeon (Huso huso L.), an anadromous species with economic and traditional relevance, is a priority in next conservation strategies in Northern Italy. The EU-LIFE NATURA project aims to reintroduce the beluga sturgeon in the Po River basin through a captive breeding program. Critical requirements for the success of the program are river connectivity and knowledge of genetic diversity of the selected broodstocks to ensure self-sustainability of reintroduced populations. Here, the four broodstocks used for the reintroduction of beluga sturgeon have been genetically screened, genotyping 13 loci and sequencing mitochondrial DNA cytochrome b (Cyt b) gene and the entire mitochondrial DNA control region (D-Loop). The four broodstocks showed a medium-high level of nuclear genetic variability and the presence of two sub-populations, evidencing a total level of inbreeding coefficients able to sustain the good potential as future breeders. Mitochondrial analyses showed a genetic variability comparable to wild populations, further strengthening the positive potential of the investigated broodstock. Therefore, this study, showed how the degree of genetic diversity found within the four broodstocks used for H. huso reintroduction in the Po River basin could be suitable to ensure the success of the program, avoiding the inbreeding depression associated with founder effect and captive breeding. Full article