Environmental Science & Technology Letters Environ.最新文献

Influenza A viruses present important public health risks, with recent outbreaks of highly pathogenic avian influenza (HPAI) H5N1 in dairy cattle raising concerns about potential transmission through raw milk consumption. This study investigated the persistence of influenza A virus H1N1 PR8 (IAV PR8) in raw cow milk at 4 °C. We found a first-order decay rate constant of −2.05 day^–1 equivalent to a T₉₉ of 2.3 days. Viral RNA remained detectable for at least 57 days with no degradation. Pasteurization (63 °C for 30 min) reduced infectious virus to undetectable levels and reduced viral RNA concentrations, but reduction was less than 1 log₁₀. These findings highlight the potential risk of zoonotic virus transmission through raw milk consumption and underscore the importance of milk pasteurization. The prolonged persistence of viral RNA in both raw and pasteurized milk has implications for food safety assessments and environmental monitoring, particularly in the context of the environmental surveillance of influenza viruses.

Detecting and quantifying tire wear particles (TWPs) in the environment pose a unique environmental challenge due to their chemical complexity. There are emerging concerns around TWPs due to their potential high numbers of particles released, outnumbering microplastics, as well as the leaching of toxic additives such as 6-PPD which has been linked to the death of salmon even when present at very low levels (<0.1 μg/L). Analytical techniques such as pyrolysis gas chromatography mass spectrometry (Py-GC/MS) and thermal extraction-desorption gas chromatography mass spectrometry (TED-GC/MS) have been used but also demonstrate limitations including low sample mass, low sample throughput, and complex characterization and quantification procedures. This work aims to overcome these challenges by developing a new approach which utilizes a coupling between thermogravimetric analysis (TGA) and gas chromatography-mass spectrometry (GC/MS). This work is the first to harness conventional TGA-GC/MS for the analysis of tire rubber, with the detection of additives such as 6-PPD, while also pioneering a novel mode of operation, PyroTGA-GC/MS, using fast heating to enable robust quantitative analysis of TWPs in road dust. The limits of detection and quantification of 0.08/0.16 μg and 0.20/0.40 μg for SBR and PI, respectively, are lower than those achieved using Py-GC/MS and TED-GC/MS for SBR and align with those achieved for PI. This study reveals a clear link between the ratio of PI to SBR and the proportion of heavy goods vehicles. This work solves key issues in tire particle analysis related to sample size and throughput. By overcoming these limitations, we introduce a technique that provides an economically viable solution for large-scale commercial analysis of tire rubber and particles.

Detecting and quantifying tire wear particles (TWPs) in the environment pose a unique environmental challenge due to their chemical complexity. There are emerging concerns around TWPs due to their potential high numbers of particles released, outnumbering microplastics, as well as the leaching of toxic additives such as 6-PPD which has been linked to the death of salmon even when present at very low levels (<0.1 μg/L). Analytical techniques such as pyrolysis gas chromatography mass spectrometry (Py-GC/MS) and thermal extraction-desorption gas chromatography mass spectrometry (TED-GC/MS) have been used but also demonstrate limitations including low sample mass, low sample throughput, and complex characterization and quantification procedures. This work aims to overcome these challenges by developing a new approach which utilizes a coupling between thermogravimetric analysis (TGA) and gas chromatography–mass spectrometry (GC/MS). This work is the first to harness conventional TGA-GC/MS for the analysis of tire rubber, with the detection of additives such as 6-PPD, while also pioneering a novel mode of operation, PyroTGA-GC/MS, using fast heating to enable robust quantitative analysis of TWPs in road dust. The limits of detection and quantification of 0.08/0.16 μg and 0.20/0.40 μg for SBR and PI, respectively, are lower than those achieved using Py-GC/MS and TED-GC/MS for SBR and align with those achieved for PI. This study reveals a clear link between the ratio of PI to SBR and the proportion of heavy goods vehicles. This work solves key issues in tire particle analysis related to sample size and throughput. By overcoming these limitations, we introduce a technique that provides an economically viable solution for large-scale commercial analysis of tire rubber and particles.

Sustained browning of northern waters has prompted inquiries into the drivers of increasing concentrations of organic matter. While reduced sulfur deposition is a key cause, an increasing role of hydrologic mechanisms as a result of cleaner air and progressing climate change has been repeatedly suggested. How these controls act remains however unclear. Here we examine over 30 years of organic carbon concentration and discharge data from four reference streams located across Norway to pinpoint consistent hydrologic changes that may promote water browning. Stable slopes with changing intercepts of the concentration-discharge relations indicate that the influence of air pollution on soil solution chemistry is plausible, supporting available chemical explanations from a hydrologic perspective. Decreasing ratios of concentration to discharge variability, observed in autumn over the years, point to less spatial heterogeneity of the sources of organic carbon. A clear rise in the frequency of runoff events, which increases the opportunities for dissolved organic carbon to transit from soil to streams, also indicates higher hydrologic connectivity and more even mobilization of carbon sources. More connected sources and more frequent runoff events, which jointly enhance the likelihood of organic carbon reaching rivers, may thus contribute to the observed browning of northern waters.

The growing issue of electronic waste (E-waste), driven by the exponential growth in electronic device usage, presents significant environmental and economic challenges. E-waste production has surged, increasing by ∼2 million metric tonnes (Mt) annually, reaching 60 Mt in 2023, with projections suggesting it will exceed 70 Mt by 2030. Despite China, the United States, and India being the top E-waste producers, their recycling rates remain critically low at 16%, 15%, and 1%, respectively. E-waste contains valuable metals, such as gold (Au), silver (Ag), and copper (Cu), which comprise ∼60% of its composition. However, only 17.4% of the global E-waste was appropriately recycled in 2023. This Review discusses the latest data on E-waste, evaluates current metal recovery methods, and emphasizes the urgency of sustainable solutions to mitigate environmental hazards and promote a circular economy. The paper also covers case studies highlighting challenges and potential strategies for enhancing metal recovery efficiency, contributing significantly to global sustainability efforts and waste management.

Oxidative potential (OP) is increasingly recognized as a more health-relevant metric than particulate matter (PM) mass concentration because of its response to varying chemical compositions. Given the limited research on the OP of complex combustion aerosols, the effects of aging processes on their OP remain underexplored. We used online instruments to track the evolution of OP [via dithiothreitol (DTT) assays] during the aging of wood burning and coal combustion emissions by hydroxyl-radical-driven photooxidation and dark ozonolysis. We observed very substantial increases in the intrinsic OP (OP_m^DTT) of complex combustion aerosols (e.g., OP_m^DTT up to 100 pmol min^–1 μg^–1 for OH-aged wood burning emissions) within 1 day of equivalent aging. Further analysis in relation to the degree of oxidation revealed a potential for generalizing the OP of carbonaceous aerosols with average carbon oxidation state ${\overline{OS}}_c$ values ranging from −1.5 to −0.5 by assuming they have a constant OP_m^DTT value of ∼10 ± 6 pmol min^–1 μg^–1. Additionally, we uncovered a strong dependency of OP_m^DTT on both the source/precursor and aging pathway with ${\overline{OS}}_c$ above ∼−0.5. OH photooxidation was identified as an exceptionally efficient pathway for generating highly oxidized, multifunctionalized, and DTT-active products, particularly from wood burning emissions.

Oxidative potential (OP) is increasingly recognized as a more health-relevant metric than particulate matter (PM) mass concentration because of its response to varying chemical compositions. Given the limited research on the OP of complex combustion aerosols, the effects of aging processes on their OP remain underexplored. We used online instruments to track the evolution of OP [via dithiothreitol (DTT) assays] during the aging of wood burning and coal combustion emissions by hydroxyl-radical-driven photooxidation and dark ozonolysis. We observed very substantial increases in the intrinsic OP (OP_m ^DTT) of complex combustion aerosols (e.g., OP_m ^DTT up to 100 pmol min^-1 μg^-1 for OH-aged wood burning emissions) within 1 day of equivalent aging. Further analysis in relation to the degree of oxidation revealed a potential for generalizing the OP of carbonaceous aerosols with average carbon oxidation state values ranging from -1.5 to -0.5 by assuming they have a constant OP_m ^DTT value of ∼10 ± 6 pmol min^-1 μg^-1. Additionally, we uncovered a strong dependency of OP_m ^DTT on both the source/precursor and aging pathway with above ∼-0.5. OH photooxidation was identified as an exceptionally efficient pathway for generating highly oxidized, multifunctionalized, and DTT-active products, particularly from wood burning emissions.

Aminiums are significant components of organic aerosols with intense research on aliphatic aminiums. However, the mechanisms of formation of aromatic aminiums in urban aerosols remain elusive. Highly time-resolved PM_2.5 samples were collected in the center of Shanghai (China) during the winter to investigate the origin and formation of aminiums. The dominant aminium groups were aliphatic (mainly dimethylaminium and monomethylaminium). Anilinium was the third most abundant aminium. The concentrations of anilinium and total aminiums showed higher levels during the daytime and on weekdays. This finding combined with source apportionment analysis suggested that the daily and weekly scale variations of anthropogenic activities (e.g., traffic for commuting) were mainly responsible for the fluctuations in aminium concentrations (particularly aromatic aminiums). The acid dependence of aliphatic aminium formation was significantly stronger than that of aromatic aminium formation. Aliphatic and aromatic aminiums were significantly negatively and positively correlated with ozone, respectively, suggesting that the oxidative processes weakened the abundance of aliphatic aminiums but promoted the formation of aromatic aminiums. The molecular characterization of aromatic aminiums suggested that the atmospheric degradation of higher-molecular-weight aromatic amine compounds was an important mechanism for anilinium formation in urban aerosols. Thus, this study provides novel insights into the formation of aromatic aminiums.