Ammonium Carbon Research Articles

Long-Term Exposure to Fine Particulate Matter (PM2.5) Components and Precocious Puberty Among School-Aged Children: Cross-Sectional Study.

The increasing incidence of precocious puberty is a major health challenge for Chinese children, while related risk factors remain less well explored. Exposure to ambient fine particulate matter (PM2.5) is a leading environmental hazard in China. Although certain components of PM2.5 have been reported to be endocrine disruptors for sex hormones, population-based evidence is still lacking on the association between PM2.5 exposure and precocious puberty in China. Based on a cross-sectional survey covering 30 cities in 2017 to 2019, this study was designed to explore the association between long-term exposure to PM2.5 and its 5 major components with precocious puberty in China and to check the potential modifying effects of family-related and personal factors. We included 34,105 children aged 6 to 9 years. We collected the 5-year average concentrations of PM2.5 and its 5 major components (sulfate, nitrate, ammonium, organic matter, and black carbon) in the area (at a spatial resolution of 0.1° × 0.1°) where each school was located. We used mixed effect logistic regression to estimate the effect sizes of the total mass of PM2.5 and each of its components on precocious puberty, and we examined the modifying effects of family-related and personal factors using an additional interactive term. A weighted quantile sum (WQS) regression model was applied to identify the weights of each component in explaining the effect size of the total mass of PM2.5. We found that the odds ratio (OR) for precocious puberty per IQR increase in the concentration of total PM2.5 mass was 1.27 (95% CI 0.92-1.75) for the whole population, 2.12 (95% CI 1.27-3.55) for girls, and 0.90 (95% CI 0.62-1.30) for boys. Similarly, the effect sizes of the 5 major components were all substantial for girls but minimal for boys. Results of the WQS analysis showed that organic matter could explain the highest proportion of the effect of PM2.5, with the weight of its contribution being 0.71. Modification effects of family income and dietary habits were only observed in certain population subgroups. Long-term exposure to total PM2.5 mass was significantly associated with precocious puberty in girls, with organic matter identified as the major effect contributor. The results add evidence on the detrimental effects of PM2.5 on children's development and growth.

A wearable antifouling electrochemical sensor integrated with an antimicrobial microneedle array for uric acid detection in interstitial fluid.

A wearable antifouling electrochemical sensor integrated with an antimicrobial microneedle array for uric acid detection in interstitial fluid.

Impacts of changes in PM2.5 concentrations and their major components on blood pressure during pregnancy.

Impacts of changes in PM2.5 concentrations and their major components on blood pressure during pregnancy.

Analyzing the Role of Chemical Mechanism Choice in Wintertime PM2.5 Modeling for Temperature Inversion-Prone Areas.

Chemical transport models are used for federal compliance demonstrations when areas are out of attainment, but there is no guidance for choosing a chemical mechanism. With the 2024 change of the annual PM2.5 standard and the prevalence of multiday wintertime inversion episodes in the western U.S., understanding the wintertime performance of chemical transport models is important. This study explores the impact of chemical mechanism choice on the Community Multiscale Air Quality (CMAQ) model performance for PM2.5 and implications for attainment demonstration in inversion-prone areas in the western United States. Total and speciated PM2.5 observations were used to evaluate wintertime CMAQ simulations using four chemical mechanisms. The study evaluated intermechanism differences in total and secondary PM2.5 and the impact of meteorology at sites with observed multiday temperature inversions. Model performance for total PM2.5 was similar across chemical mechanisms, but intermechanism differences for total and secondary PM2.5 were exacerbated during inversion periods, suggesting that modeled chemistry contributes to the model bias. Results suggest that nitrate, ammonium, and organic carbon are secondary species for which model results do not agree or perform to standard evaluation metrics in scientific literature. These findings show a need for mechanistic investigations of the causes of these differences.

Unveiling the Dissociation Mechanism of Diglycine Perchlorate.

Determining the dissociation mechanism of perchlorate materials remains a top priority to address sustainability, handling, processing, and synthesis issues of new and existing high-energy density materials vital to many industrial processes. We determined the dissociation mechanism of diglycine perchlorate (DGPCl) using vibrational spectroscopy, which unveiled the formation of ammonium perchlorate (AP) and carbon at high temperatures. Our studies establish that DGPCl shows multiple phase transitions upon heating. The reversible melting transition (∼100 °C) is characterized by reorientations in hydrogen bonding, thereby modifying glycine geometry. The irreversible liquid-liquid transition (∼170 °C) is guided by the dissociation of cationic glycine and the formation of an intermediate complex, showing a change in color. Above 240 °C, the liquid state transforms to a solid state with the evolution of H2O, HCN, CO, CH4, N2O, CO2, etc., gases, detected using high-resolution rovibrational and mass spectroscopy. Notably, no NH3 release was observed, ruling out an earlier prediction. This results in the formation of AP, one of the strongest oxidizers, as residue enveloped by carbon layers, a potential fuel. The observed exothermic enthalpy above 240 °C is ∼405 kJ/mol. The discovery may pave the way toward finding better organic perchlorates with modified properties to mitigate challenges with the existing ones.

Do Water Pollutant Reduction Projects Promote or Limit Carbon Reduction? Evidence from Building a Beautiful China

The total control of major water pollutants (TCMWP) is a critical strategy for improving water quality in China, with the added benefit of yielding climate-related advantages. This study uses the emission factor method to quantify the reductions in pollutants and carbon emissions resulting from China’s implementation of TCMWP. A synergy scale for pollution and carbon reduction was constructed to assess the co-benefits of reducing the Chemical Oxygen Demand (COD) and ammonium nitrogen (NH4+-N) and carbon dioxide (CO2) emissions. Furthermore, to account for regional variations in energy structure regulation strategies, whether aggressive or unified, we developed Pollutant Synergistic Carbon Reduction Pathways at the Regional (R.PSCRP) model framework level to evaluate the carbon emission reduction potential of TCMWP during the “14th Five-Year Plan” period. The study revealed that China’s unified TCMWP employs different but highly effective combinations of emission reduction paths across different regions. Notably, new renovations and expansions of wastewater treatment facilities (NRE-WWTFS) and pipeline network construction and renovation (CR-PNK) together accounted for 89.3% of the total emission reduction. The construction of key water pollutant reduction projects plays a significant role in reducing carbon emissions at the district level compared to direct discharge practices. Additionally, indirect emissions resulting from TCMWP implementation account for approximately 50% of the total carbon reduction achieved. By aligning either harmonized or independent energy adjustment targets, regions were able to achieve substantial pollution and carbon reduction benefits, ranging from 7.5 to 8 million tons of CO2-equivalent.

Association of early life exposure to PM2.5 and its components with offspring neurodevelopment: a prospective birth cohort study

Association of early life exposure to PM2.5 and its components with offspring neurodevelopment: a prospective birth cohort study

Fine Particulate Matter, Its Constituents, and Spontaneous Preterm Birth

The associations of exposure to fine particulate matter (PM2.5) and its constituents with spontaneous preterm birth (sPTB) remain understudied. Identifying subpopulations at increased risk characterized by socioeconomic status and other environmental factors is critical for targeted interventions. To examine associations of PM2.5 and its constituents with sPTB. This population-based retrospective cohort study was conducted from 2008 to 2018 within a large integrated health care system, Kaiser Permanente Southern California. Singleton live births with recorded residential information of pregnant individuals during pregnancy were included. Data were analyzed from December 2023 to March 2024. Daily total PM2.5 concentrations and monthly data on 5 PM2.5 constituents (sulfate, nitrate, ammonium, organic matter, and black carbon) in California were assessed, and mean exposures to these pollutants during pregnancy and by trimester were calculated. Exposures to total green space, trees, low-lying vegetation, and grass were estimated using street view images. Wildfire-related exposure was measured by the mean concentration of wildfire-specific PM2.5 during pregnancy. Additionally, the mean exposure to daily maximum temperature during pregnancy was calculated. The primary outcome was sPTB identified through a natural language processing algorithm. Discrete-time survival models were used to estimate associations of total PM2.5 concentration and its 5 constituents with sPTB. Interaction terms were used to examine the effect modification by race and ethnicity, educational attainment, household income, and exposures to green space, wildfire smoke, and temperature. Among 409 037 births (mean [SD] age of mothers at delivery, 30.3 [5.8] years), there were positive associations of PM2.5, black carbon, nitrate, and sulfate with sPTB. Adjusted odds ratios (aORs) per IQR increase were 1.15 (95% CI, 1.12-1.18; P < .001) for PM2.5 (IQR, 2.76 μg/m3), 1.15 (95% CI, 1.11-1.20; P < .001) for black carbon (IQR, 1.05 μg/m3), 1.09 (95% CI, 1.06-1.13; P < .001) for nitrate (IQR, 0.93 μg/m3), and 1.06 (95% CI, 1.03-1.09; P < .001) for sulfate (IQR, 0.40 μg/m3) over the entire pregnancy. The second trimester was the most susceptible window; for example, aORs for total PM2.5 concentration were 1.07 (95% CI, 1.05-1.09; P < .001) in the first, 1.10 (95% CI, 1.08-1.12; P < .001) in the second, and 1.09 (95% CI, 1.07-1.11; P < .001) in the third trimester. Significantly higher aORs were observed among individuals with lower educational attainment (eg, less than college: aOR, 1.16; 95% CI, 1.12-1.21 vs college [≥4 years]: aOR, 1.10; 95% CI, 1.06-1.14; P = .03) or income (<50th percentile: aOR, 1.17; 95% CI, 1.14-1.21 vs ≥50th percentile: aOR, 1.12; 95% CI, 1.09-1.16; P = .02) or who were exposed to limited green space (<50th percentile: aOR, 1.19; 95% CI, 1.15-1.23 vs ≥50th percentile: aOR, 1.12; 95% CI, 1.09-1.15; P = .003), more wildfire smoke (≥50th percentile: aOR, 1.19; 95% CI, 1.16-1.23 vs <50th percentile: aOR, 1.13; 95% CI, 1.09-1.16; P = .009), or extreme heat (aOR, 1.51; 95% CI, 1.42-1.59 vs mild temperature: aOR, 1.11; 95% CI, 1.09-1.14; P < .001). In this study, exposures to PM2.5 and specific PM2.5 constituents during pregnancy were associated with increased odds of sPTB. Socioeconomic status and other environmental exposures modified this association.

Multiyear high-temporal-resolution measurements of submicron aerosols at 13 French urban sites: data processing and chemical composition

Abstract. This paper presents a first comprehensive analysis of long-term measurements of atmospheric aerosol components from aerosol chemical speciation monitor (ACSM) and multiwavelength Aethalometer (AE33) instruments collected between 2015 and 2021 at 13 (sub)urban sites as part of the French CARA (Chemical Characterization of Particles) program. The datasets contain the mass concentrations of major chemical species within submicron aerosols (PM1), namely organic aerosols (OAs), nitrate (NO3-), ammonium (NH4+), sulfate (SO42-), non-sea-salt chloride (Cl−), and equivalent black carbon (eBC). Rigorous quality control, technical validation, and environmental evaluation processes were applied, adhering to both guidance from the French Reference Laboratory for Air Quality Monitoring (LCSQA) and the Aerosol, Clouds, and Trace Gases Research Infrastructure (ACTRIS) standard operating procedures. Key findings include geographical differences in the aerosol chemical composition, seasonal variations, and diel patterns, which are influenced by meteorological conditions, anthropogenic activities, and proximity to emission sources. Overall, OA dominates PM1 at each site (43 %–60 % of total mass), showing distinct seasonality with higher concentrations (i) in winter, due to enhanced residential heating emissions, and (ii) in summer, due to increased photochemistry favoring secondary aerosol formation. NO3 is the second most important contributor to PM1 (15 %–30 %), peaking in late winter and early spring, especially in northern France, and playing a significant role during pollution episodes. SO4 (8 %–14 %) and eBC (5 %–11 %) complement the major fine-aerosol species, with their relative contributions strongly influenced by the origin of air masses and the stability of meteorological conditions, respectively. A comparison with the 3D chemical transport model (CTM) CHIMERE shows high correlations between simulations and measurements, albeit with an OA concentration underestimation of 46 %–76 %. Regional discrepancies in NO3 concentration levels emphasize the importance of these datasets with respect to validating air quality models and tailoring air pollution mitigation strategies. The datasets can be found at https://doi.org/10.5281/zenodo.13318298 (Chebaicheb et al., 2024).

Prenatal exposure to PM2.5 and its composition on child growth trajectories in the first two years: A prospective birth cohort study

Prenatal exposure to PM2.5 and its composition on child growth trajectories in the first two years: A prospective birth cohort study

Anthropogenic and biogenic pollutants in a forested environment: SPRUCE-22 campaign overview

Anthropogenic and biogenic pollutants in a forested environment: SPRUCE-22 campaign overview

Colony‐forming and single‐cell picocyanobacteria nitrogen acquisition strategies and carbon fixation in the brackish Baltic Sea

AbstractPicocyanobacteria are widespread and globally significant primary producers. In brackish waters, picocyanobacterial populations are composed of diverse species with both single‐cell and colony‐forming lifestyles. Compared to their marine counterparts, brackish picocyanobacteria are less well characterized and the focus of research has been weighted toward single‐cell picocyanobacteria. Here, we investigate the uptake dynamics of single and colony‐forming picocyanobacteria using incubations with dual carbon‐13 and inorganic (ammonium and nitrate) or organic (urea and amino acids) nitrogen‐15 sources during August and September 2020 in the central Baltic Sea. Phytoplankton community and group‐specific uptake rates were obtained using an elemental analyzer isotope ratio mass spectrometer (EA‐IRMS) and nano secondary‐ion mass spectrometry (NanoSIMS). Picocyanobacteria contributed greater than one third of the ammonium, urea, amino acids, and inorganic carbon community uptake/fixation in September but &lt; 10% in August when phytoplankton biomass was higher. Overall, single‐cell ammonium and urea uptake rates were significantly higher for single‐celled compared to colonial picocyanobacteria. In a 6‐yr offshore central Baltic Sea time series (2015–2020), summer abundances of colonial picocyanobacteria reached up to 105 cells mL−1 and represented &gt; 5% of the average phytoplankton biomass, suggesting that they are periodically important for the ecosystem. Colonial strain identification was not distinguishable using 16S rRNA gene amplicon data, highlighting a need for refined tools for identification of colonial forms. This study shows the significance of single‐celled brackish picocyanobacteria to nutrient cycling and the importance of considering uptake and lifestyle strategies when assessing the role of picocyanobacteria in aquatic ecosystems.

Interaction between Extreme Temperature Events and Fine Particulate Matter on Cardiometabolic Multimorbidity: Evidence from Four National Cohort Studies.

Accumulating evidence linked extreme temperature events (ETEs) and fine particulate matter (PM2.5) to cardiometabolic multimorbidity (CMM); however, it remained unknown if and how ETEs and PM2.5 interact to trigger CMM occurrence. Merging four Chinese national cohorts with 64,140 free-CMM adults, we provided strong evidence among ETEs, PM2.5 exposure, and CMM occurrence. Performing Cox hazards regression models along with additive interaction analyses, we found that the hazards ratio (HRs) of CMM occurrence associated with heatwave and cold spell were 1.006-1.019 and 1.063-1.091, respectively. Each 10 μg/m3 increment of PM2.5 concentration was associated with 17.9% (95% confidence interval: 13.9-22.0%) increased risk of CMM. Similar adverse effects were also found among PM2.5 constituents of nitrate, organic matter, sulfate, ammonium, and black carbon. We observed a synergetic interaction of heatwave and PM2.5 pollution on CMM occurrence with relative excess risk due to the interaction of 0.999 (0.663-1.334). Our study provides novel evidence that both ETEs and PM2.5 exposure were positively associated with CMM occurrence, and the heatwave interacts synergistically with PM2.5 to trigger CMM.

New insights into black carbon light absorption enhancement: A comprehensive analysis of two differential behaviors

New insights into black carbon light absorption enhancement: A comprehensive analysis of two differential behaviors

Association between PM2.5 constituents and cardiometabolic risk factors: Exploring individual and combined effects, and mediating inflammation

Association between PM2.5 constituents and cardiometabolic risk factors: Exploring individual and combined effects, and mediating inflammation

Effects of carbon to nitrogen ratio on nitrogen removal in a single-stage microaerobic system: A model-based evaluation

Effects of carbon to nitrogen ratio on nitrogen removal in a single-stage microaerobic system: A model-based evaluation

Ammonium-Enhanced Arsenic Mobilization from Aquifer Sediments.

Ammonium-related pathways are important for groundwater arsenic (As) enrichment, especially via microbial Fe(III) reduction coupled with anaerobic ammonium oxidation; however, the key pathways (and microorganisms) underpinning ammonium-induced Fe(III) reduction and their contributions to As mobilization in groundwater are still unknown. To address this gap, aquifer sediments hosting high As groundwater from the western Hetao Basin were incubated with 15N-labeled ammonium and external organic carbon sources (including glucose, lactate, and lactate/acetate). Decreases in ammonium concentrations were positively correlated with increases in the total produced Fe(II) (Fe(II)tot) and released As. The molar ratios of Fe(II)tot to oxidized ammonium ranged from 3.1 to 3.7 for all incubations, and the δ15N values of N2 from the headspace increased in 15N-labeled ammonium-treated series, suggesting N2 as the key end product of ammonium oxidation. The addition of ammonium increased the As release by 16.1% to 49.6%, which was more pronounced when copresented with organic electron donors. Genome-resolved metagenomic analyses (326 good-quality MAGs) suggested that ammonium-induced Fe(III) reduction in this system required syntrophic metabolic interactions between bacterial Fe(III) reduction and archaeal ammonium oxidation. The current results highlight the significance of syntrophic ammonium-stimulated Fe(III) reduction in driving As mobilization, which is underestimated in high As groundwater.

Ambient fine particulate matter chemical composition associated with in-hospital case fatality, hospital expenses, and length of hospital stay among patients with heart failure in China.

Previous studies have observed the adverse effects of ambient fine particulate matter pollution (PM2.5) on heart failure (HF). However, evidence regarding the impacts of specific PM2.5 components remains scarce. We included 58 129 patients hospitalised for HF between 2013 and 2017 in 11 cities of Shanxi, China from inpatient discharge database. We evaluated exposure to PM2.5 and its components ((sulphate (SO42-), nitrate (NO3-), ammonium (NH4+), organic matter (OM) and black carbon (BC)), along with meteorological factors using bilinear interpolation at each patients' residential address. We used multivariable logistic and linear regression models to assess the associations of these components with in-hospital case fatality, hospital expenses, and length of hospital stay. Increase equivalents to the interquartile range (IQR) in OM (odds ratio (OR) = 1.13; 95% confidence interval (CI) = 1.02, 1.26) and BC (OR = 1.14; 95% CI = 1.02, 1.26) were linked to in-hospital case fatality. Per IQR increments in PM2.5, SO42-, NO3-, OM, and BC were associated with cost increases of 420.62 (95% CI = 285.75, 555.49), 221.83 (95% CI = 96.95, 346.71), 214.93 (95% CI = 68.66, 361.21), 300.06 (95% CI = 176.96, 423.16), and 303.09 (95% CI = 180.76, 425.42) CNY. Increases of 1 IQR in PM2.5, SO42-, OM, and BC were associated with increases in length of hospital stay of 0.10 (95% CI = 0.02, 0.19), 0.09 (95% CI = 0.02, 0.17), 0.10 (95% CI = 0.03, 0.17), and 0.16 (95% CI = 0.08, 0.23) days. Our findings suggest that ambient SO42-, OM, and BC might be significant risk factors for HF, emphasising the importance of formulating customised guidelines for the chemical constituents of PM and controlling the emissions of the most dangerous components.

PM2.5 constituents associated with childhood obesity and larger BMI growth trajectory: A 14-year longitudinal study

PM2.5 constituents associated with childhood obesity and larger BMI growth trajectory: A 14-year longitudinal study

The development of the biological soil crust regulates the fungal distribution and the stability of fungal networks.

The heterogeneous composition of fungi plays an indispensable role in the foundation of the multifunctionalities of ecosystems within drylands. The precise mechanisms that govern fluctuations in soil fungal assemblages in dryland ecosystems remain incompletely elucidated. In this study, biological soil crusts (biocrusts) at different successional stages in the Gurbantunggut Desert were used as substrates to examine the characteristics and driving factors that influence fungal abundance and community dynamics during biocrust development using qPCR and high-throughput sequencing of the ITS2 region. The findings showed that the physicochemical properties changed significantly with the development of biocrusts. In particular, total nitrogen increased 4.8 times, along with notable increases in ammonium, total phosphorus (2.1 times) and soil organic carbon (6.5 times). Initially, there was a rise in fungal abundance, which was subsequently followed by a decline as the biocrust developed, with the highest abundance detected in lichen crust (2.66 × 107 copies/g soil) and the lowest in bare sand (7.98 × 106 copies/g soil). Ascomycetes and Basidiomycetes emerged as dominant phyla, collectively forming 85% of the fungal community. As the biocrust developed, noticeable alterations occurred in fungal community compositions, resulting from changes in the relative proportions of Dothideomycetes, Lecanoromycetes and unclassified ascomycetes. Nitrogen, phosphorus, organic carbon content, and pH of biocrusts were identified as direct or indirect regulators of fungal abundance and community structure. The complexity of fungal networks increased as biocrusts developed as revealed by network analysis, but reduced in the stability of fungal communities within algal and lichen crusts. Keystone species within the fungal community also underwent changes as biocrust developed. These results suggested that shifts in interspecies relationships among fungi could further contribute to the variation in fungal communities during the development of biocrusts.