ACS Central Science最新文献

Drinking water halogenated disinfection byproducts (DBPs) have become an increasing health concern. However, the endocrine-disrupting effects of DBPs have not been well evaluated, and the limited available data have inhibited a comprehensive understanding of their health risks. In this study, a total of 43 DBPs were evaluated for their estro-androgenic effects using two types of human breast cancer cells. Among the tested DBPs, 16 exhibited estrogenic/antiestrogenic/androgenic/antiandrogenic effects, and the effects could be observed even at concentrations typically detected in drinking water. Iodinated and polyhalogenated DBPs generally showed higher effects than other species. For a broader comparison, DBP endocrine-disrupting effect data from this study and previous studies were summarized. It was found that the endocrine disruption efficacy of DBPs followed the rank order of iodinated > brominated > chlorinated species, and halophenolic DBPs were potential endocrine-disrupting compounds. Moreover, molecular docking results demonstrated that the binding of DBPs to estro-androgenic receptors was dominated by hydrophobic bonding, hydrogen bonding, halogen bonding, and van der Waals forces. The force strength and molecular volume were related to the magnitude of the estro-androgenic effects. Iodinated DBPs and polyhalogenated DBPs tended to have larger binding forces than other analogues and thus exhibited stronger effects.

Incorporation of pollutants, e.g., heavy metals, or critical elements, e.g., lithium, as impurities in mineral phases can significantly affect their mobility or sequestration in the environment. Even when present at low concentrations, impurities can alter the solubility and reactivity of the host mineral. In this study, we investigate the incorporation of trace amounts of iron (Fe³⁺) and chromium (Cr³⁺) during the crystal growth of the aluminum (Al³⁺) hydroxide, gibbsite, a major component of bauxite ores, an important soil mineral, and a dominant mineral phase in stored radioactive wastes. Using a comprehensive suite of analytical techniques, we show that both Cr³⁺ and Fe³⁺ can be incorporated into the gibbsite lattice during coprecipitation by replacing Al³⁺ in octahedral sites. These small amounts are consistent with limited to no structural isomorphism shared between Al³⁺ and Cr³⁺/Fe³⁺ hydroxide precipitates, nor room temperature miscibility of their isostructural M₂O₃ oxide forms, in contrast with oxyhydroxide forms where Al³⁺ and Fe³⁺ share similar structural topologies. Despite the limited uptake of Cr³⁺/Fe³⁺, we show that these impurities have significant implications for gibbsite dissolution behavior. The limited uptake of Cr³⁺/Fe³⁺ (e.g. 0.43% Cr³⁺ and 0.4% Fe³⁺), we show that these impurities have significant implications for gibbsite dissolution behavior and subsequent reactivity in complex environments.

Indirect photolysis driven by photochemically produced reactive intermediates (PPRIs) is pivotal for the transformations and fates of pollutants in nature. While well-studied in bulk water, indirect photolysis processes at environmental interfaces remain largely unexplored. This study reveals a significant acceleration of indirect photodegradation of organic pollutants at the soil–water interface of wetlands. Organic pollutants experienced ubiquitously enhanced indirect photodegradation at the soil–water interfaces, with rates 1.41 ± 0.01 to 4.27 ± 0.03-fold higher than those in bulk water. This enhancement was observed across various natural and artificial wetlands, including coastal wetlands and rice paddies. In situ mapping indicated that soil–water interfaces act as hotspots, concentrating both organic pollutants and PPRIs by 9.30- and 4.27-folds, respectively. This synchronized colocation is the primary cause of the accelerated pollutant photolysis. Additionally, the contribution of each PPRI species to pollutant photolysis and a coupled transformation pathway at the soil–water interface significantly differed from those in bulk water. For instance, the contribution of singlet oxygen to metoxuron photolysis increased from 10.1% in bulk water to 44.4% at the soil–water interface. Our study highlights the rapid indirect photolysis of organic pollutants at the soil–water interfaces, offering new insights into the natural purification processes in wetlands as “Earth’s kidneys.”

California’s organic waste diversion law, SB 1383, mandates a 75% reduction in organics disposal by 2025 to reduce landfill methane emissions. Composting will likely be the primary alternative to landfilling, and 75–100 new large-scale composting facilities must be sited in the state to meet its diversion goal. We developed a strategy for evaluating site suitability for commercial composting by incorporating land-use, economic, and environmental justice criteria. In our Baseline scenario, we identified 899 candidate sites, and nearly all are within a cost-effective hauling distance of cropland and rangelands for compost application. About half of sites, mostly in rural areas, are not within a cost-effective collection distance of enough municipal organics to supply an average-sized facility. Conversely, sites near cities have greater access to organics but cause greater health damages from ammonia and volatile organic compounds emitted during the composting process. The additional required composting capacity corresponds to $266–355 million in annual damages from air pollution. However, this excludes avoided emissions from landfilling, and damages could be reduced by 56% if aerated static piles are used instead of windrows. Siting a higher number of smaller decentralized facilities could also help equally distribute air pollution to avoid concentrating burdens in certain communities.

We identified and analyzed suitable compost facility sites in California to help the state meet its organic waste diversion law.

Demulsification technology for separation of oil–water (O/W) emulsions, especially those stabilized by surfactants, is urgently needed yet remains highly challenging due to their inherent stability characteristics. Electrocoalescence has emerged as a promising solution owing to its simplicity, efficacy, and versatility, yet hindered by substantial energy consumption (e.g., >50 kWh/m³) along with undesirable Faradic reactions. Herein, we propose an innovative electric demulsification technology that leverages conductive membrane microchannels to confine oil droplets from the oil–water emulsion for achieving high energy-efficient coalescence of oil droplets. The proposed system reduces the required voltage down to 12 V, 2 orders of magnitude lower than that of conventional electrocoalescence systems, while achieving a similar separation efficacy of 91.4 ± 3.0% at a low energy consumption (3 kWh/m³) and an ultrahigh permeability >3000 L/(m²·h·bar). In situ fluorescence microscopy combined with COMSOL simulations provided insight into the fundamental mechanistic steps of an electric demulsification process confined to membrane microchannels: (1) rapid electric-field redistribution of oil droplet surfactant molecules, (2) enhanced collision probability due to confined oil droplet concentration under dielectrophoretic forces, and (3) increased collision efficacy facilitated by the membrane pore structure. This strategy may revolutionize the next generation of demulsification and oil–water separation innovations.

Microcystis spp. threaten freshwater ecosystems through the proliferation of cyanobacterial harmful algal blooms (cyanoHABs) and production of the hepatotoxin, microcystin. While microcystin and its biosynthesis pathway, encoded by the mcy genes, have been well studied for over 50 years, a recent study found that Microcystis populations in western Lake Erie contain a transcriptionally active partial mcy operon, in which the A2 domain of mcyA and mcyB-C are present but the mcyD-J genes are absent. Here, we investigate the potential biosynthetic products and the evolutionary history of this partial operon. Our results reveal two candidate tetrapeptide constructs, with an X variable position, to be produced by strains with the partial operon. The partial operon appears necessary and sufficient for tetrapeptide biosynthesis and likely evolved from a single ancestor hundreds to tens of thousands of years ago. Bioactivity screens using Hep3B cells indicate a mild elevation of some markers of hepatotoxicity and inflammation, suggesting the need to further assess the effects of these novel secondary metabolites on freshwater ecosystems and public health. The need to assess these effects is even more pressing given the detection of tetrapeptides in both culture and western Lake Erie, which is a vital source of fresh water. Results from this study emphasize previous findings in which novel bacterial secondary metabolites may be derived from the molecular evolution of existing biosynthetic machinery under different environmental forcings.

The move toward electrification is critical for decarbonizing the energy sector but may exacerbate energy unaffordability without proper safeguards. Addressing this challenge requires capturing neighborhood-scale dynamics to uncover the blind spots in residential electricity inequality. Based on publicly available, multisourced remote sensing and census data, we develop a high-resolution, spatiotemporally explicit machine learning (ML) framework to predict tract-level monthly electricity consumption across the conterminous U.S. from 2013–2020. We then construct the electricity affordability gap (EAG) metric, defined as the gap between electricity bills and 3% of household income, to better identify energy-vulnerable communities over space and time. The results show that our framework largely improves the resolution of electricity consumption data while achieving an R² of 0.82 compared to the Low-Income Energy Affordability Data (LEAD). We estimate an annual $16.18 billion economic burden on the ability to afford electricity bills, exceeding current federal appropriations in alleviating energy difficulties. We also observe pronounced seasonal and urban-rural disparities, with monthly EAG in summer and winter being 2–3 times greater than other seasons and rural residents facing burdens up to 1.7 times higher than their urban counterparts. These insights inform equitable electrification by addressing spatiotemporal mismatches and multiple jurisdictional challenges in energy justice efforts.