Environmental Science & Technology Letters Environ.最新文献

Finding relevant chemicals in the vast (known) chemical space is a major challenge for environmental and exposomics studies leveraging nontarget high resolution mass spectrometry (NT-HRMS) methods. Chemical databases now contain hundreds of millions of chemicals, yet many are not relevant. This article details an extensive collaborative, open science effort to provide a dynamic collection of chemicals for environmental, metabolomics, and exposomics research, along with supporting information about their relevance to assist researchers in the interpretation of candidate hits. The PubChemLite for Exposomics collection is compiled from ten annotation categories within PubChem, enhanced with patent, literature and annotation counts, predicted partition coefficient (logP) values, as well as predicted collision cross section (CCS) values using CCSbase. Monthly versions are archived on Zenodo under a CC-BY license, supporting reproducible research, and a new interface has been developed, including historical trends of patent and literature data, for researchers to browse the collection. This article details how PubChemLite can support researchers in environmental and exposomics studies, describes efforts to increase the availability of experimental CCS values, and explores known limitations and potential for future developments. The data and code behind these efforts are openly available. PubChemLite can be browsed at https://pubchemlite.lcsb.uni.lu.

Finding relevant chemicals in the vast (known) chemical space is a major challenge for environmental and exposomics studies leveraging nontarget high resolution mass spectrometry (NT-HRMS) methods. Chemical databases now contain hundreds of millions of chemicals, yet many are not relevant. This article details an extensive collaborative, open science effort to provide a dynamic collection of chemicals for environmental, metabolomics, and exposomics research, along with supporting information about their relevance to assist researchers in the interpretation of candidate hits. The PubChemLite for Exposomics collection is compiled from ten annotation categories within PubChem, enhanced with patent, literature and annotation counts, predicted partition coefficient (logP) values, as well as predicted collision cross section (CCS) values using CCSbase. Monthly versions are archived on Zenodo under a CC-BY license, supporting reproducible research, and a new interface has been developed, including historical trends of patent and literature data, for researchers to browse the collection. This article details how PubChemLite can support researchers in environmental and exposomics studies, describes efforts to increase the availability of experimental CCS values, and explores known limitations and potential for future developments. The data and code behind these efforts are openly available. PubChemLite can be browsed at https://pubchemlite.lcsb.uni.lu.

Per- and polyfluoroalkyl substances (PFAS) have garnered increasing attention in recent years, and non-targeted analysis (NTA) has become essential for elucidating novel PFAS structures. NTA and PFAS research have been dominated by liquid chromatography–mass spectrometry (LC-MS) with gas chromatography–mass spectrometry (GC-MS) used less often as evidenced by bibliometrics. However, the performance of GC-MS in NTA studies (GC-NTA) rivals that of LC-ESI-MS, and GC-MS is shown to cover a complementary chemical space. An LC-ESI-MS amenability model applied to a list of approximately 12,000 PFAS revealed that less than 10% of known PFAS chemistry is predicted to be amenable to typical LC-MS analysis. Therefore, there is strong potential for applying GC-MS methods to more fully assess the PFAS environmental contamination landscape, uniquely shedding light on both known and novel PFAS, especially within the chemical space realm of volatile and semivolatile PFAS. Waste streams from fluorochemical manufacturing facilities have been heavily studied using LC-MS and targeted GC-MS; however, GC-NTA is needed to discover novel PFAS that are not amenable to LC-MS emitted from facilities. Studies on the incineration of PFAS-containing materials, such as aqueous film forming foam, have focused on the destruction of parent compounds, and little is known about the transformation products formed during such processes. GC-NTA holds the potential to elucidate transformation products formed when PFAS are incinerated. Wastewater treatment plants and landfills are known sources of PFAS to the environment, yet GC-NTA is needed to understand air emissions of PFAS and PFAS transformation products from these sources. Consumer products are known to lead to indoor exposures to PFAS via emissions to air and dust, but research in this area has either used LC-MS or targeted GC-MS. Despite the challenges with advancing GC-NTA, we call on NTA researchers, grantors, managers, and other stakeholders to recognize the potential and necessity of GC-NTA in PFAS research so that we may face these challenges together.

Zebrafish are widely used as model organisms in biological research with embryos typically reared in media supplemented with methylene blue (MB) as an antifungal agent. Many animal care guidelines recommend the use of MB during early development stages. However, this practice overlooks MB’s known effects as a monoamine oxidase inhibitor and antidepressant. This study demonstrates that at recommended husbandry concentrations, MB significantly reduces zebrafish locomotion in a 24 h behavior assay, a finding consistent across strains and laboratories. Gene expression profiling and pharmacological experiments using the MAO-inhibitor deprenyl suggest that MB induces hypolocomotion by increasing the serotonergic tone. Importantly, MB use in standard embryo medium masks known hypolocomotor responses to fluoxetine, a common aquatic contaminant and selective serotonin-reuptake inhibitor. These findings have significant implications for the increasing use of larval zebrafish in high-throughput neurotoxicity assessments and highlight the need to reconsider the use of MB in zebrafish research. The study emphasizes the importance of eliminating potential confounds in husbandry practices and improving experimental protocol reporting to enhance reproducibility in zebrafish-based (eco)toxicity testing.

The sustainability of lithium mining is one of the critical factors for a successful transition to renewable energy. A potential practice to alleviate brine level decline and loss of adjacent fresh groundwater from brine pumping in the salt pans (salars) is through injection of spent brines into the subsurface. The quality and possible impacts of injecting spent brines have not been fully investigated. Here we present data for major and trace elements in natural brines, brines and salts from evaporation ponds, and wastewaters from a lithium processing plant at the Salar de Uyuni in Bolivia, the largest known global lithium deposit. The investigation reveals that evaporation of natural brines results in highly saline brines (TDS ≈ 360 g/kg) with low pH (3.2) and elevated concentrations of lithium, boron, and arsenic (up to ∼50 mg/kg) that could modify the chemical composition and mineral saturation upon release to the environment. The extremely high arsenic concenrations and low pH also have potential environmental impacts. In contrast, the processing plant generates saline and low-saline wastewater streams with high pH (∼10) and lower solute concentrations that could dilute the natural lithium reservoir, while the high pH limits their disposal options.

Understanding the biodegradation of organic pollutants is crucial for assessing the persistence and fate of these contaminants and improve their risk assessment, eventually drawing policy. The occurrence of organophosphate ester (OPE) flame retardants and plasticizers has been widely reported in the marine environment. However, few studies have assessed the potential of marine microorganisms to degrade them, particularly under oceanic conditions. Here, we report the results of six degradation experiments where in situ bacterial communities were challenged with environmentally relevant concentrations of OPEs in the Atlantic and Southern Oceans. Hydrophobic aryl-OPEs significantly decreased by 60% and 25% in the Atlantic and Southern Oceans, respectively. In Atlantic waters, up to 40% of OPE depletion was due to sorption to cells and close to 20% to biodegradation. The cold temperatures of the Southern Ocean resulted in a slower, nondetectable biodegradation, further confirmed by bacterial production results. Bacterial composition exposed to OPEs also showed a larger degree of changes in the Atlantic than in the Southern Ocean. Significant negative correlations were found between the fold changes in bacterial production and the decreases in OPE concentrations, suggesting that bacterial carbon demand is directly related to OPE biodegradation in the oceans.

Road salt (e.g., NaCl) application in cold-temperature regions has increased Cl^– concentrations in freshwater. Removing Cl^– from water is challenging because it is highly soluble. This paper is the first to demonstrate and characterize the removal of Cl^– from stormwater via Friedel’s salt (Ca₄Al₂(OH)₁₂Cl₂(H₂O)₄) precipitation (FSP), achieved by adding calcium oxide (CaO) and sodium aluminate (NaAlO₂). Laboratory tests were done on Cl^– removal with FSP using a range of Ca/Al/Cl ratios in deionized (DI) water and stormwater samples impacted by road salt. Even the lowest doses resulted in significant removal of Cl^– with maximum removal rates for comparable Ca/Al/Cl ratios of 72% and 84% in stormwater and DI water, respectively. Temporal experiments in stormwater and DI water indicate that most of the Cl^– removal occurred within the first 10 min of reaction time. Potential applications of FSP were demonstrated for two hypothetical scenarios based on a well-characterized, salt-impacted lake. The first scenario indicates that a 30% reduction in stormwater Cl^– mass is sufficient to maintain concentrations below 150 mg/L. A second scenario with an initial 300 mg/L lake water concentration shows the potential for implementing FSP in low-flow pump and treat systems for the rehabilitation of road-salt-impaired lakes.

Nonmethane volatile organic compound (NMVOC) pollution severely impacts urban atmospheric quality. We propose a top-down method for estimating NMVOC emissions based on glyoxal─an important oxidation product of NMVOCs observed from space. We applied the wind rotation aggregation and exponential modified Gaussian methods to estimate the glyoxal effective lifetime and production rate in the glyoxal plumes downwind. These methods were applied to 60 cities worldwide, and the effective production rate of glyoxal was screened out in 22 cities, ranging from 0.8 ± 0.3 to 13.7 ± 3.3 mol/s. The results indicate significant correlation with total NMVOC emission from bottom-up inventory (r = 0.85, p < 0.01). Additionally, we utilized daily satellite results to identify biomass burning emission sources in Australian fire events. Our research offers a novel perspective on monitoring of urban and transient NMVOC emissions and provides a new data source for emission reduction policymaking.

With widespread adult-use cannabis legalization in the United States, cannabis consumption lounges have rapidly emerged. However, studies of indoor cannabis exposure are still lacking, particularly in public spaces. We measured fine particle (PM_2.5) mass concentrations and particle number concentrations at a cannabis consumption lounge in Los Angeles, California. We compared particle concentrations at the street front, backyard, and two smoking cabins and identified three busyness levels to investigate concentration differences in the smoking cabin. The results showed that PM_2.5 concentrations in the smoking cabin exceeded 1600 μg/m³. During busy hours (12:00 p.m. to 10:00 p.m.), the median (IQR) PM_2.5 concentration [31.2 (317.3) μg/m³] was >10 times higher than overnight (10:00 p.m. to 9:00 a.m.) concentrations [3.0 (1.3) μg/m³] and >3 times higher than concentrations [8.5 (13.8) μg/m³] during less busy hours (9:00 a.m. to 12:00 p.m.). The particle number concentration during active cannabis use [median of 1.9 × 10⁴, interquartile range (IQR) of 1.3 × 10⁴ particles/cm³] was significantly higher than the baseline (median of 0.9 × 10⁴, IQR of 0.3 × 10⁴ particles/cm³). Our research shows high fine and ultrafine particle concentrations in a cannabis consumption lounge, which could facilitate future studies of related health effects and the development of targeted regulations.