Understanding the differences in the approaches used to assess household air pollution (HAP) is crucial for evaluating HAP-related health effects and interpreting the effectiveness of stove-fuel interventions. Our review aims to understand how exposure to HAP from solid fuels was measured in epidemiological studies in children under five. We conducted a search of PubMed, EMBASE, Cochrane Central Register of Controlled Trials, Global Health Library, Web of Science, and CINAHL to identify English-language research articles published between January 1, 2000 and April 30, 2022. Two researchers applied the inclusion and exclusion criteria independently. Study region, type of measurement, study design, health outcomes, and other key characteristics were extracted from each article and analyzed descriptively. Our search strategy yielded 2229 records, of which 185 articles were included. A large proportion was published between 2018 and 2022 (42.1%), applied a cross-sectional study design (47.6%), and took place in low- or lower middle-income countries. Most studies (130/185, 70.3%) assessed HAP using questionnaires/interviews, most frequently posing questions on cooking fuel type, followed by household ventilation and cooking location. Cooking frequency/duration and children's location while cooking was less commonly considered. About 28.6% (53/185) used monitors, but the application of personal portable samplers was limited (particulate matter [PM]: 12/40, 30.0%; carbon monoxide [CO]: 13/34, 38.2%). Few studies used biomarkers or modeling approaches to estimate HAP exposure among children under five. More studies that report household and behavioral characteristics and children's location while cooking, apply personal exposure samplers, and perform biomarker analysis are needed to advance our understandings of HAP exposure among infants and young children, who are particularly susceptible to HAP-related health effects.

Studies have linked gaseous air pollutants to multiple health effects via inflammatory pathways. Several major inflammatory biomarkers, including C-reactive protein (CRP), fibrinogen, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) have also been considered as predictors of cardiovascular disease. However, there has been no meta-analysis to evaluate the associations between gaseous air pollutants and these typical biomarkers of inflammation to date. To evaluate the overall associations between short-term and long-term exposures to ambient ozone (O₃), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), carbon dioxide (CO) and major inflammatory biomarkers including CRP, fibrinogen, IL-6 and TNF-α. A meta-analysis was conducted for publications from PubMed, Web of Science, Scopus and EMBASE databases up to Feb 1st, 2021. The meta-analysis included 38 studies conducted among 210,438 participants. Generally, we only observed significant positive associations between short-term exposures to gaseous air pollutants and inflammatory biomarkers. For a 10 μg/m³ increase in short-term exposure to O₃, NO₂, and SO₂, there were significant increases of 1.05% (95%CI: 0.09%, 2.02%), 1.60% (95%CI: 0.49%, 2.72%), and 10.44% (95%CI: 4.20%, 17.05%) in CRP, respectively. Meanwhile, a 10 μg/m³ increase in NO₂ was also associated with a 4.85% (95%CI: 1.10%, 8.73%) increase in TNF-α. Long-term exposures to gaseous air pollutants were not statistically associated with these biomarkers, but the study numbers were relatively small. Subgroup analyses found more apparent associations in studies with better study design, higher quality, and smaller sample size. Meanwhile, the associations also varied across studies conducted in different geographical regions. Short-term exposure to gaseous air pollutants is associated with increased levels of circulating inflammatory biomarkers, suggesting that a systemic inflammatory state is activated upon exposure. More studies on long-term exposure to gaseous air pollutants and inflammatory biomarkers are warranted to verify the associations.

Forest fires significantly affect the wildlife, vegetation, composition and structure of the forests. This study explores the potential of partially burnt wood recovered in the aftermath of a recent Canadian forest fire incident as a feedstock for generating hydrogen-rich syngas through hydrothermal gasification. Partially burnt wood was gasified in hydrothermal conditions to study the influence of process temperature (300–500 °C), residence time (15–45 min), feed concentration (10–20 wt%) and biomass particle size (0.13 mm and 0.8 mm) using the statistical Taguchi method. Maximum hydrogen yield and total gas yield of 5.26 mmol/g and 11.88 mmol/g, respectively were obtained under optimized process conditions at 500 °C in 45 min with 10 wt% feed concentration using biomass particle size of 0.13 mm. The results from the mean of hydrogen yield show that the contribution of each experimental factors was in the order of temperature > feed concentration > residence time > biomass particle size. Other gaseous products obtained at optimum conditions include CO₂ (3.43 mmol/g), CH₄ (3.13 mmol/g) and C₂–C₄ hydrocarbons (0.06 mmol/g).

Biomass of Java plum (JP) and amaltash (AT) seeds were employed to remove arsenic from synthetic wastewater, cost effectively. The prepared biomasses were characterized by FE-SEM, EDX, FTIR, XRD, and ICP techniques. Experimentation the optimization study has been carried out by using Design-software 6.0.8. Response surface methodology has been applied to design the experiments where we have used three factors and three levels Box-Behnken design (BBD). Arsenic removal ability of bio-sorbents was evaluated and optimized by varying pH, adsorbent dose concentration of arsenic in synthetic wastewater. For 2.5 mg/L arsenic concentration and 80 mg adsorbent dose at pH 8.8 Java plum seeds (JP) based bio-adsorbent removed ∼93% and amaltash seeds (AT) based bio-adsorbent removed ∼91% arsenic from synthetic wastewater. The adsorption behaviour better explained following Freundlich model (R² = 0.99) compared to Temkin model (R² = 0.986) for As (III) ions. The adsorption capacity was 1.45 mg g⁻¹ and 1.42 mg g⁻¹ for JP and AT, respectively after 80 min under optimal set of condition. The adsorption kinetics was explained by either pseudo-first order model or Elovich model.

We aimed to update the evidence-base of long-term noise exposures from road, rail, and aircraft traffic on both non-accidental and cardiovascular mortality.A systematic review and meta-analysis were conducted following PRISMA guidelines. The literature was searched using PubMed, Scopus, Web of Science, and EMBASE for the period between January 01, 2000 and October 05, 2020. 13 studies were selected for final review. The risk of bias and overall quality of evidence was evaluated using a pre-defined list of criteria. Risk estimates from each study were converted into per 10 dB higher of Ldₑₙ for each traffic source. Inverse-Variance heterogeneity (I-Vhet) meta-analysis was used to pool these individual risk estimates, along with assessment of heterogeneity and publication bias. Sensitivity analyses include using random-effect model and leave-one-out meta-analysis. Subgroup analyses by study design and noise exposure assessment were conducted to explore potential sources of heterogeneity.For road traffic, the pooled relative risk (RR) per 10 dB higher Ldₑₙ for mortality from non-accidental causes was 1.01 (95% CI: 0.98, 1.05) (5 studies, I² = 78%), CVD was 1.01 (95% CI: 0.98, 1.05) (5 studies, I² = 41%), ischemic heart disease (IHD) was 1.03 (95% CI: 0.99, 1.08) (7 studies, I² = 46%), and stroke was 1.05 (95% CI: 0.97, 1.14) (5 studies, I² = 62%). The overall quality of evidence for most meta-analyses was rated as very low to low, except for CVD or IHD mortality, for which the quality of evidence was rated as moderate. A possible threshold of 53 dB was visually suggested for CVD-related mortality from road traffic noise in the trend analysis. For aircraft noise, pooled estimates were based on fewer studies and varied by mortality outcomes.Evidence of long-term exposure to traffic noise on mortality remains weak except the association between road traffic noise and IHD mortality. High-quality longitudinal studies are required to better characterise mortality effects of traffic noise.

Soil microbes influence the uptake of toxic metals (TMs) by changing soil characteristics, bioavailability and translocation of TMs, and soil health indicators in polluted environment. The potential effect of Streptomyces pactum (Act12) and Bacillus consortium (B. subtilis and B. licheniformis; 1:1) on soil enzymes and bacterial abundance, bioavailability and translocation of Zn and Cd by Symphytum officinale, and physiological indicators in soil acquired from Fengxian (FX) mining site. Act12 and Bacillus consortium were applied at 0 (CK), 0.50 (T1), 1.50 (T2), and 2.50 (T3) g kg⁻¹ in a split plot design and three times harvested (H). Results showed that soil pH significantly dropped, whereas, electrical conductivity increased at higher Act12 and Bacillus doses. The extractable Zn lowered and Cd increased at each harvest compared to their controls. Soil β-glucosidase, alkaline phosphatase, urease and sucrase improved, whereas, dehydrogenase reduced in harvest 2 and 3 (H2 and H3) as compared to harvest 1 (H1) after Act12 and Bacillus treatments. The main soil phyla individually contributed ∼5–55.6%. Soil bacterial communities’ distribution was also altered by Act12 and Bacillus amendments. Proteobacteria, Acidobacteria, and Bacteroidetes increased, whereas, the Actinobacteria, Chloroflexi, and Gemmatimonadetes decreased during the one-year trial. The Zn and Cd concentration significantly decreased in shoots at each harvest, whereas, the roots concentration was far higher than the shoots, implicating the rhizoremediation by S. officinale. Accumulation factor (AF) and bioconcentration ratio (BCR) of Zn and Cd in shoots were lower and remained higher in case of roots than the standard level (≥1). BCR values of roots indicated that S. officinale can be used for rhizoremediation of TMs in smelter/mines-polluted soils. Thus, field trials in smelter/mines contaminated soils and the potential role of saponin and tannin exudation in metal translocation by plant will broaden our understanding about the mechanism of rhizoremediation of TMs by S. officinale.

Increasing levels of road noise are creating new anthropogenic soundscapes that may affect wildlife globally. Bats, which form about a third of all mammal species, are sensitive bioindicators, and may be particularly vulnerable because of their dependency on echolocation. Here we present the first controlled field experiment with free-living bats. Using a Before-After-Control-Impact phantom road experimental design, we examine the impacts of traffic noise on their activity and feeding behaviour. Disentangling the impacts of traffic noise from other co-varying exposures such as habitat quality, the experiment demonstrates a significant negative effect on the activity of each of the five, ecologically different, species (genus for Myotis spp.) examined. This suggests that the results are widely applicable. The negative effects are largely attributable to noise in the sonic spectrum, which elicited aversive responses in all bat species tested,whereas responses to ultrasoundwere restricted to a single species. Our findings demonstrate that traffic noise can affect bat activity at least 20m away from the noise source. For Pipistrellus pipistrellus and Pipistrellus pygmaeus, feeding behaviour, as well as overall activity, was negatively affected. Ecological Impact Assessments are therfore needed wherever there are significant increases in traffic flow, and not just when new roads are built. Further research is required to identify effective mitigation strategies, to delineate the zone of influence of road noise, and to assess whether there is any habituation over time.

The heating of edible oils during cooking activities promotes the emissions of pollutants that have adverse impacts on the health of humans. This study investigated the evaporative emissions of fifteen (15) commonly used cooking oils. Split-plot experimental design under the response surface methodology framework was used to study singular and interaction effects of influencing parameters (temperature, volume of cooking oil and time) on cooking oil evaporation rate and pollutants emissions (i.e. Particulate matter of aerodynamic diameter ≤1 μm (PM₁.₀); ≤2.5 μm (PM₂.₅); ≤10 μm (PM₁₀); Total Suspended Particulate (TSP); Total Volatile Organic Compounds -TVOCs, and Carbon Monoxide- CO) on a groundnut oil sample that served as a case study. Obtained values of density, viscosity, kinematic viscosity, smoke, flash and fire points were; 873–917 kg/m³; 1.12–9.7 kg/ms; 2.4–3.4 m²/s; 96 -100 °C; 124–179 °C and 142–186 °C, respectively. The role of temperature as the most significant parameter influencing the rate of evaporative emissions was established. Evaporation rate and pollutants emission from unrefined samples were the highest. The restricted maximum likelihood (REML) analysis results suggested a strong relationship between the actual values and the predicted values as R-squared values obtained were greater than 0.8 for all the responses. These results suggest that minimal rates of evaporation and pollutants emission from heating cooking oils can be achieved with a high volume of the cooking oil at moderate temperature levels.

Sediment quality monitoring is commonly used to assess for river pollution by industrial activities, but requires knowledge of pre-disturbance conditions. This has long been a critical knowledge gap for assessing pollution of the Lower Athabasca River within the Athabasca Oil Sands Region (AOSR) because sediment quality monitoring started 30 years after mining operations began in 1967. Here, we analyze oil-sands pollution indicator metals vanadium (V) and nickel (Ni) in sediment cores from five Athabasca River floodplain lakes spanning from 17 km upstream to 58 km downstream of central oil sands operations. These data are used to define pre-development baseline (i.e., reference) concentrations and assess for enrichment in sediment deposited after 1967. Measurements of organic and inorganic matter content were used to differentiate periods of strong and weaker Athabasca River influence in the sediment records, as needed to discern pathways of metal deposition. Numerical analyses reveal that post-1967 V and Ni enrichment factors have remained below the 1.5 threshold for ‘minimal enrichment’ (sensu Birch, 2017) in stratigraphic intervals of strong river influence in the floodplain lakes. Thus, concentrations of V and Ni carried by Athabasca River sediment have not become measurably enriched since onset of oil sands development, as demonstrated by our before-after study design with >99.99% power to detect a 10% increase above pre-development baselines. At the closest lake (<1 km) to oil sands operations, however, enrichment factors for V and Ni increased to 2.1 and 1.5, respectively, in the mid-1980s and have remained at this level when river influence was weaker, indicating contamination via atmospheric transport. Localized enrichment within the oil sands region via atmospheric pathways is a greater concern for ecosystems and society than local and far-field transport by fluvial pathways.