Environmental Science & Technology Letters Environ.最新文献

Microplastic pollution is now ubiquitous in the environment, making human exposure to microplastics unavoidable. This results in the detection of microplastics in human bodies, including blood. However, the pathways through which microplastics enter the bloodstream still need to be clarified, despite the studies of several direct and indirect routes. Herein, the potential occurrence of microplastics in infusion therapy sets, including glass infusion bottles, plastic infusion bottles, plastic infusion bags, and plastic infusion tubes, was investigated. The results showed that a total of eight microplastics, ranging from 4 to 148 μm in size, were identified from three PP-bottled infusion, three PE-bagged infusion, and one glass-bottled infusion, consisting of PE, PA, PS, and PC, while no particles were detected in infusion tubes. The samples containing microplastics accounted for 11.66% of the total samples with 1–2 particles/unit. Although microplastics were detected in infusion solutions, microplastic exposure to the bloodstream via infusion therapy is minimal, owing to their low abundance. Nevertheless, these findings suggested that infusion therapy might be a direct pathway of microplastics entering the bloodstream, partially or fully explaining the presence of microplastics in human blood and tissues.

Liquid crystal monomers (LCMs) exemplify a group of chemicals prevalent in indoor environments. However, current frameworks for assessing the environmental persistence of chemicals predominantly focus on outdoor environments, often overlooking indoor environments. Here, we model and compare the persistence of LCMs across indoor and outdoor multimedia environments. Our findings reveal that, when assessed in an outdoor context, <10% of the investigated LCMs exhibit overall persistence comparable to those of persistent organic pollutants regulated by the Stockholm Convention, and one-third to two-thirds of the investigated LCMs meet the Stockholm Convention’s medium-specific half-life thresholds for persistence. However, we found a notable disparity between indoor and outdoor persistence: Approximately 90% of the investigated LCMs demonstrate substantially prolonged persistence indoors, 10 times longer on average, and up to ∼150 times longer in some cases, compared to outdoors. This long indoor persistence is mainly attributed to the low volatility of LCMs and their high affinity for indoor surface compartments. Our work highlights the indoor environment’s role as both a continuous source of human exposure to LCMs and a potential reservoir for long-term regional contamination. Therefore, a tailored, fit-for-purpose assessment of “indoor persistence”, focusing on chemicals predominantly found in indoor environments, carries profound implications for both human and ecological health.

Road tunnels play a crucial role in modern road networks, in both urban and non-urban areas, and necessitate frequent cleaning and washing due to the harsh tunnel environment. As a result, road tunnels are considered hot spots for the emission of road-related pollutants into the environment. In this study, we conducted extensive measurements of tire wear particles (TWPs) and 18 tire-derived chemicals (TDCs) during the washing process, throughout a 21-day treatment period in a rectangular sedimentation basin in concrete, and during the discharge of treated wash water. Our key findings indicate that TWPs are effectively retained in the sedimentation basin, demonstrating that simple mitigation measures can prevent their release near the source. However, several TDCs displayed high concentrations, mobility, and leachability, leading to inadequate retention in the basin. Moreover, some TDCs exhibited negative treatment performance, resulting in higher concentrations in the treated wash water than in the untreated wash water. Importantly, our findings can be applied to not only tunnel wash water but also normal road runoff, as sedimentation basins are widely used in many countries. This study provides a novel and significant contribution to the evolving understanding of the presence and fate of TWPs and TDCs in the environment.

In contrast with phthalate esters (PAEs), many non-PAE plasticizers (NPPs) remain poorly characterized in their environmental distribution. Our work explored the spatial distributions of 44 NPPs in airborne fine particles (PM_2.5) from 13 Chinese cities as well as the temporal change of contamination at a selected city (Jinan, Shandong Province). The results revealed ubiquitous distributions of several groups of NPPs in the ambient environment, such as oleates, adipates, citrates, and isobutyrates. The total abundance of NPPs (ΣNPPs) ranged from 0.37 to 54.7 ng/m³, and the ratios of ΣNPPs to ΣPAEs ranged from 0.06 to 4.17 across the study sites. The spatial variations in ΣNPPs appeared to be significantly associated with the gross domestic product of the cities, indicating a link between economic prosperity and environmental releases of NPPs. The ratios of ΣNPPs to ΣPAEs also exhibited a significant temporal increase during the period of 2015–2020 in the study site located in Jinan, providing strong evidence of the increasing applications of NPPs relative to PAEs in previous years. Our work constitutes one of the first reports on the spatiotemporal distributions of NPPs over a large geographic range.

Here, we evaluated the uptake and biotransformation mechanism of the systemic fungicide phenamacril in hydroponic/soil–plant systems. Phenamacril was preferentially accumulated in shoots with the translocation factor up to 3.5 (or 6.9) in wheat (or rice) during 144 h of the uptake kinetic experiment. Apart from upward xylem translocation, phenamacril could also be redistributed from shoots to roots (0.4%) through phloem transport and then released into the rhizosphere surrounding solution (1.7%) through plant excretion via a split-root experiment. Then, 76.4% (or 70.4%) of phenamacril was transformed to 14 (or 12) metabolites in hydroponic-wheat (or hydroponic-rice) systems after 28 days of exposure, with nine of them first identified based on nontarget analysis. The proposed metabolic pathways included hydroxylation, hydrolysis, isomerization, dehydrogenation, deamination, dehydration, decarboxylation, reduction, and conjugation reactions, which were modulated by genes overexpression of metabolic enzymes (e.g., cytochrome P450). Notably, metabolite M-157 was predicted to be more persistent in environments and more toxic to rats and aquatic organisms than phenamacril by theoretical calculation. This study highlights that phloem transport and plant excretion may result in cycling chemical contamination, and the transformation products may possess elevated toxicities, thus should be considered in estimating the contamination of pesticides in crops and environments.

With the rapid global expansion of mobile communication networks and the introduction of new radiofrequencies, especially above 6 GHz with the emergence of 5G/6G technology, there is an urgent requirement to investigate and tackle the possible effects of radiofrequency electromagnetic field emissions on wildlife. Here, we highlight (i) the pressing need for robust research on this topic, (ii) the inadequacy of existing guidelines from the International Commission for Non-Ionizing Radiation Protection, which solely address human health, and (iii) the lack of attention given to wildlife exposure to radiofrequency electromagnetic field levels when creating and/or restoring wildlife habitats and deploying new radiofrequency electromagnetic field sources. We call for a common worldwide agenda that would prioritize research on wildlife exposure to radiofrequency electromagnetic fields and for an independent international organization to address this issue. Finally, we provide key recommendations aimed at reducing wildlife exposure to radiofrequency electromagnetic fields while awaiting further evidence.

Ammonium (NH₄⁺) is a significant component of fine aerosol particles (PM_2.5), and its behavior in the atmosphere is crucial to air pollution. We present a novel study that analyzes the vertical distribution and temporal trends of NH₄⁺ in the urban boundary layer of Beijing, tracking hourly concentrations throughout a complete haze episode. Our results unveil a surprising single-peak profile of NH₄⁺ at heights of 300–700 m in the urban boundary layer with its hourly concentration reaching ∼50 μg m^–3, which is 3 times higher than that at the ground level, in contrast to the conventional patterns of decreasing concentrations with height. The vertical structure is closely related to the observed escape of ammonia (NH₃) or NH₄⁺ from upwind industrial sources via elevated chimneys. The NH₄⁺ plumes emitted through these sources are prone to transport at an altitude of 270–750 m for approximately 6 h, covering >250 km to Beijing. This study reveals that non-agricultural point emissions of NH₄⁺ impact the vertical patterns of aerosol NH₄⁺ in the urban boundary layer, demonstrating potential opportunities for limiting such emission sources to curb PM_2.5 pollution in the North China Plain.

Climate change and urbanization are increasing the distribution of insect vectors of infectious diseases. Dengue virus is an arbovirus that causes nearly 100 million symptomatic infections per year and is endemic in 124 countries, and the range of its mosquito vectors continues to increase. Surveillance of dengue virus infections is complicated by the fact that infections can be asymptomatic, and symptoms may not be readily recognizable to clinicians. Here we show that wastewater monitoring can be used to detect dengue virus RNA to yield information about the circulation of dengue infections in a community. We collected three samples of wastewater solids per week from three different wastewater treatment plants in Miami-Dade County, Florida, where dengue infections were locally acquired. Using molecular methods, we tested wastewater solids for RNA from the 4 dengue virus serotypes and consistently detected dengue virus 3 RNA at all three wastewater plants and did not detect the other 3 serotypes. According to publicly available data on dengue infections, a vast majority of infections were caused by serotype 3. Wastewater detection of dengue virus RNA is possible with as few as 4.23 laboratory confirmed dengue cases per 1 million people based on publicly available infection data.