Effects Of Pollution Research Articles

Long-term exposure to air pollution and road traffic noise and incidence of dementia in the Danish Nurse Cohort.

We examined the association of long-term exposure to air pollution and road traffic noise with dementia incidence in the Danish Nurse Cohort. Female nurses were followed for dementia incidence (hospital contact or medication prescription) from 1993/1999 to 2020. Air pollution and road traffic noise levels were estimated at nurses' residences, and their associations with dementia were examined using Cox regression models. Of 25,233 nurses 1409 developed dementia. Particulate matter with a diameter of ≤2.5µm (PM2.5) was associated with dementia incidence, after adjusting for lifestyle, socioeconomic status, and road traffic noise (hazard ratio [95% confidence interval] 1.35 [1.15-1.59] per interquartile range of 2.6µg/m3). There was no association of PM2.5 with dementia in physically active nurses. Association with road traffic noise diminished after adjusting for PM₂.₅ (1.02 [0.93-1.11] per 7.6dB). Long-term exposure to air pollution increases risk of dementia, and physical activity may moderate this risk. Long-term exposure to air pollution was associated with increased risk of dementia among female nurses from the Danish Nurse Cohort. Association of air pollution with dementia was independent of road traffic noise. Association of road traffic noise with dementia diminished after adjusting for air pollution. Physical activity moderated adverse effects of air pollution on dementia.

Indoor and outdoor NO2 and SO2 levels in 13 randomly selected preschools from 7 districts in Mpumalanga Province, South Africa

AbstractBackgroundAir pollution is a serious worldwide issue, where both outdoor and indoor air quality have a substantial impact on the health of children. Children are more vulnerable to the effects of air pollution due to their developing respiratory systems and higher respiration rates than adults. These children dedicate a substantial amount of time to the preschool setting. The study sought to evaluate the concentration of NO2 and SO2 in both outdoor and indoor environments of preschool facilities.MethodsConcurrently, the levels of NO2 and SO2 were measured indoors and outdoors at 13 randomly selected preschools in 7 districts in Mpumalanga Province, South Africa. Radiello passive air samplers were employed to collect gaseous samples.ResultsThe mean levels of NO2 indoors and outdoors were within the recommended criteria outlined by the World Health Organization (WHO), specifically target levels 1–3. Additionally, these values were also below the air quality guides outlined by South Africa, both for yearly and 1‐h mean measurements. Nevertheless, both levels remained above the suitable threshold of 10 µg m−3 outlined by the WHO air quality guidelines.ConclusionsIt is important to implement proactive measures such as enhancing airflow systems, employing air filters and reducing potential sources of air pollution in preschools, to aid in reducing exposure to indoor and outdoor NO2 and SO2.

Specific biomass burning tracers in air pollution in Zagreb, Croatia

Biomass burning is considered a renewable energy source whose household usage is rapidly increasing throughout Europe, largely encouraged by the rising cost of other energy sources. With all the advantages that characterize such an energy source, there are several disadvantages mostly from the air quality standpoint, and consequently with regard to the influence it may have on human health and climate change. Considering the side effects of air pollution, it is important to identify the composition and sources of air pollutants precisely. This study investigated the presence of biomass combustion-specific tracers in the air of Zagreb, Croatia, a city affected by increased air pollution mostly during wintertime. Biomass burning markers in terms of anhydrosugars, namely levoglucosan, mannosan, and galactosan were monitored in particulate matter PM10. A sampling of PM10 particulate matter was conducted in parallel at measuring stations in the northern and southern part of the city during 30 days in each season in 2020. The results showed a significant seasonal difference in PM10 and anhydrosugar levels at both measuring stations with the same seasonal trend decreasing as follows: winter, autumn, spring, summer. Both PM10 and anhydrosugar concentrations were higher in the southern compared to the northern station. Average winter PM10 levels were 58 μg m−3 at the southern and 51 μg m−3 at the northern station, while average levoglucosan levels were 3.68 and 1.64 μg m−3 at the southern and northern stations, respectively. An average levoglucosan/PM10 contribution of 6.3 % was determined at the southern, and 3.2 % at the northern measuring station. The differences in contribution can be explained by areas more populated by households using biomass for residential heating, the dominant wind direction in the area, and influences from other districts, including long- or close-range transport. Linear regression indicated a weak correlation (R2 = 0.32) of anhydrosugars between the stations.

Assessment of Effects of Amended Bioremediation of Toxic Metal-polluted Soil using Organic Composites and Bacillus sp on Plant Growth Parameters

It has become pertinent to develop improved bioremediation techniques, to avert the deleterious effects of heavy metal pollution on agricultural productivity, and safety of its produce. In this study, cow dung, poultry wastes and their composites used as organic amendments were collected and processed, while Bacillus sp used as plant growth promoting rhizosphere was isolated and identified. Then 24 kg of fertile soil was polluted by introducing 20 mL of 0.1M lead acetate solution, before bagging 5 kg of polluted soil into ten perforated nylons. Soil sample was then analyzed before and after treatment. After mixing with Bacillus sp suspension, two of the pot experiments were amended with each of 0.5 kg cow dung only, 0.5 kg poultry wastes only and 1:1 ratio of their composites. Control samples were set up without amendment, and they were bioremediated for 25 days. Following germination of sown corn seedlings, heights of their shoots and number of leaves were monitored on day 4, weeks 2, 4 and 7, before harvesting for analysis together with soil samples. Results obtained revealed that seedlings grown on treated samples as well as properties of treatment of soil were generally better than those of control samples. Highest percentage increase in organic matter content of soil was recorded in treatment with mixture of cow dung only and Bacillus sp, with 9.28% and 7.63% increase at 33.75 mg/kg and 52.55 mg/kg of lead (Pb) pollution. Seedlings grown on samples treated with poultry wastes only, recorded the highest protein content of 161.25±5.5 mg/g, 104.99±4.95 mg/g and 79.75±3.2 mg/g protein contents, at 32.75 mg/kg, 42.02 mg/kg and 52.44 mg/kg levels of Pb pollution, respectively. The amendments also reduced bioaccumulation of Pb in corn seedlings, which was in the order; stem<leaf<root. Therefore, these amendments can be exploited for improved bioremediation of heavy metals.

AIR QUALITY MONITORING USING MACHINE LEARNING

Air pollution is a critical environmental issue with significant implications for public health and the well-being of ecosystems. This project focuses on developing an innovative solution for air pollution monitoring utilizing machine learning (ML) techniques. The primary objective is to design a system that can accurately predict, analyze, and monitor air quality in real time, providing valuable insights for effective pollution control and management. The proposed system incorporates a network of sensors strategically placed in various locations to capture diverse air quality parameters such as particulate matter, nitrogen dioxide, sulfur dioxide, and more. The collected data is then processed through ML algorithms to identify patterns, correlations, and trends, enabling the system to accurately predict air quality levels. The project aims to address traditional monitoring systems' limitations by leveraging ML models' adaptability and self-learning capabilities. By continuously updating and refining the models based on incoming data, the system becomes more adept at providing precise and timely information on air quality fluctuations. This endeavour contributes to a deeper understanding of local air pollution dynamics and empowers decision-makers with actionable insights for implementing targeted interventions. The integration of ML in air pollution monitoring represents a significant step towards creating sustainable and data-driven strategies for mitigating the adverse effects of pollution on human health and the environment. Index terms Air pollution, Machine Learning, Environmental Monitoring, Sustainability, Predictive Modeling, Sensor Network, Data Analysis.

Biomarkers: Their Vital Role in Understanding the Complexity of Marine Pollution Monitoring

The monitoring of marine pollution plays a pivotal role in our efforts to comprehend and mitigate its detrimental effects on marine ecosystems. Biomarkers, quantifiable biological indicators of exposure or effect, have emerged as indispensable tools in gauging the magnitude of pollution. This review delves into the multifaceted challenges associated with the use of biomarkers in marine pollution monitoring, including species-specific responses, sensitivity and specificity concerns, extraneous factors, species variability, an exclusive focus on single stressors, and limited knowledge. Discerning between pollution-induced impacts and natural fluctuations is made challenging by the inherent natural variability and confounding factors. Differences in sensitivity and specificity add complexity to the precision of pollution detection. Species-specific variations and the presence of multiple contaminants add layers of complexity to biomarker examination. Additionally, the lack of standardized operating procedures and insufficient information hinder the widespread adoption of biomarkers. Limited studies on specific stressors restrict our comprehensive understanding of pollution effects particularly in the Philippines. Further research, collaborative efforts, and the establishment of standardized protocols are imperative to enhance the precision and efficacy of biomarker-based monitoring in marine environments.

De novo transcriptome analysis of Protohermes xanthodes Navás (Megaloptera: Corydalidae) reveling the effects of sublethal chlorpyrifos on the expression of cholinergic neuronal genes

The insect cholinergic neuron system is the target for various pesticides, including organophosphate, carbamate and neonicotinoid pesticides. In this study, we conducted a de novo transcriptome analysis on the aquatic insect Protohermes xanthodes and identified for the first time presenting sixteen genes encoding cholinergic neuronal proteins (PxanChaT, PxanVAChT, PxanmAChR, PxannAChRs, and PxanAChEs), which are candidates for acetylcholine synthesis, transport, reception and degradation in cholinergic synapse. FPKM analysis revealed that these genes are primarily expressed in head and nerve cord of P. xanthodes larvae, and some of them are also abundant in hindgut, malpighian tubules and tracheae. After exposed to different concentrations of sublethal chlorpyrifos (CPF), expression of these cholinergic neuronal genes are generally increased and then decreased with the increase of CPF concentration, except PxannAChRα9 which is increased in both 4.2 and 8.4 μg/L CPF groups. Short-term (96 h) CPF exposure resulted in significant up-regulation of PxanAChE1 expression in P. xanthodes larvae exposed to 0.42 and 4.2 μg/L CPF concentrations, while PxanAChE2 was up-regulated only in 0.42 μg/L CPF group. After long-term (14 d) CPF exposure, PxanAChE1 expression was down-regulated in 0.168 and 0.42 μg/L CPF groups. PxanAChE2 expression was dramatically decreased in all CPF groups. Moreover, acetylcholinesterase (AChE) activity was significantly decreased across all long-term CPF exposure groups. These results suggested that sublethal exposure to CPF can disrupt the expression of cholinergic neuronal genes in P. xanthodes larvae, and implied that long-term sublethal CPF exposure may cause toxic effects on P. xanthodes larvae by inhibiting AChE activity. Furthermore, identification of cholinergic neuronal genes in P. xanthodes provided candidate molecular markers for study the toxic effects of environmental pollutants on the neuron system of an aquatic predatory insect with ecological importance.

Effects of mimicking manure removal strategies on ammonia and greenhouse gas emissions in sow pen scale models

With growing concerns about air pollution and global warming effects, the emissions of NH3 and greenhouse gases (GHGs) have become significant issues in the pig production industry. In order to discover whether optimizing manure removal strategies could alter the manure decomposition process and benefit the reduction of gas emissions, a scale model approach was used to quantify the gas emissions under controlled conditions. This study compared the gas emission reduction potential of two classic manure removal systems (scraper and pull-plug system) in three manure removal strategies: scraper-I (retaining manure for 24 h), scraper-II (retaining manure for 8 and 16 h) and pull-plug (retaining manure for 44 days). Fresh urine and faeces collected from a gestation sow house were applied to the scale models and then removed through the manure removal systems. The concentrations of gases (NH3, CH4, CO2, and N2O) within the scale model and removed slurry samples were collected and analysed (pH, electric conductivity, dry matter, total nitrogen, total ammonium nitrogen and total carbon). The results showed that emissions of CH4, CO2, and N2O from scraper-I were on average 54%, 56% and 25% lower than those from scraper-II, and 71%, 67% and 6% lower than those from pull-plug treatment, respectively. The GHGs emission rates (as CO2-equivalents) of scraper-I and scraper-II were 52% and 26.3% lower than that of pull-plug treatment respectively (P < 0.01). The emissions of NH3 displayed a temporary peak during each application of urine and removal of manure. In pull-plug treatment, the concentrations of NH3, CH4, and CO2 exponentially increased between Day 39 and Day 41. The nitrogen content, both total nitrogen and total ammonium nitrogen, within the slurry under the scraper system exhibited lower values compared to those from the pull-plug system. Conversely, the total carbon content was higher in the former system. Caution is warranted in extrapolating results to full-scale pig housing, given study limitations (e.g. small scale, mimicked scraper activity, no animals, etc.). Nevertheless, the conclusions and findings of this study provide fundamental data for understanding gas emissions from pig house manure management. This insight can guide the design and daily operations of low-emission manure removal systems in gestation sow houses.

Effect of Toxicity of Chromium (VI) Stressors Alone and Combined to High Temperature on the Histopathological, Antioxidation, Immunity, and Energy Metabolism in Fish Phoxinus lagowskii

Fish in aquatic ecosystems are often impacted by environmental stressors like temperature fluctuations and exposure to heavy metals. Chromium (Cr6+) is a known environmental pollutant that poses a threat to aquatic life. Various environmental factors, such as water temperature, have been found to affect the toxicity of dissolved chemicals in aquatic ecosystems. We investigated the toxicity of combinations of different concentrations of hexavalent chromium (Cr6+) with high temperatures in fish. Hematological indices demonstrated changes in white blood cells (WBCs), hematocrit (HCT), red blood cells (RBCs), and hemoglobin (Hb) levels during the exposure. The qualitative and semi-quantitative analyses of different tissues confirmed that higher concentrations of Cr6+ caused more significant damage than lower concentrations, with evident alterations observed in circulatory and regressive aspects. Furthermore, brain acetylcholinesterase levels decreased in both single heavy metal exposure and combined exposure at a high temperature. The activity of antioxidant oxidase and immunological parameters increased in all treatment groups compared with the control group following long-term exposure. A significant and increased effect of Cr6+ in the high-temperature groups was observed on the evaluated biomarkers, suggesting a possible synergistic effect between Cr6+ and increased temperature. The integrated biomarker response (IBR) reported the highest level of stress at 10 mg/L Cr6+ combined with high temperature. The IBR analysis revealed that the highest activity of response enzymes, such as acid phosphatase (ACP), superoxide dismutase (SOD), and glutathione S-transferases (GST), was observed in the liver, whereas the gills displayed alkaline phosphatase (ALP), GST, and SOD activity, and the kidneys demonstrated SOD, ACP, and aspartate aminotransferase (AST) to be most active. Through histopathology, antioxidant enzymes, and metabolism- and immunity-related enzymes, we determined that high temperatures enhance the potential toxicity of Cr6+ in fish. We recommend conducting a thorough assessment of the impact of climate change, particularly temperature fluctuations, when studying the toxic effects of metal pollution, like chromium, in aquatic ecosystems.

Synthesizing the Ecological and Societal Ramifications of Environmental Stressors on Philippine Marine Ecosystems: A Comprehensive Literature Review

Coral reefs, which serve as essential ecosystems that support marine biodiversity and coastal populations, are declining at an alarming rate worldwide, including in the Philippines. This study explores the specific effects of overfishing, the causes, and effects of pollution on Philippine waters to understand better rising sea levels, ocean acidification, the overall impact of climate change on coral reefs, and the value of these coral habitats to local communities. Data were acquired using a qualitative approach through literature reviews of secondary sources. The findings show that overfishing, pollution, climate change, and habitat destruction are major causes of coral reef decline in the Philippines. These factors have resulted in severe reductions in coral cover, biodiversity loss, and decreased ecosystem services. Furthermore, coral reef decline has far-reaching consequences for Philippine biodiversity, including decreased resistance to environmental stressors and greater vulnerability of coastal people. This study highlights the urgency for coordinated conservation initiatives, such as enhanced management tactics, sustainable fishing practices, and climate change mitigation measures. Recommendations include creating marine protected areas, stronger coastal development rules, and public awareness programs to support coral reef protection. Addressing coral reef loss is crucial for protecting Philippine biodiversity and ensuring the long-term viability of marine ecosystems.

The short-term effects of individual and mixed ambient air pollutants on suicide mortality: A case-crossover study

It is critical to explore intervenable environmental factors in suicide mortality. Based on 30,688 suicide cases obtained from the Mortality Surveillance System of the Jiangsu Provincial Centre for Disease Control and Prevention, we utilized a case-crossover design, and found that the OR of suicide deaths increased by a maximum of 0.71 % (95 % CI: 0.09 %, 1.32 %), 0.68 % (95 % CI: 0.12 %, 1.25 %), 0.77 % (95 % CI: 0.19 %, 1.37 %), 2.95 % (95 % CI: 1.62 %, 4.29 %), 4.18 % (95 % CI: 1.55 %, 6.88 %), and 0.93 % (95 % CI: 0.10 %, 1.77 %), respectively, for per 10 μg/m3 increase in the particulate matter (PM) with diameters ≤ 2.5 µm (PM2.5), PM with diameters ≤ 10 µm (PM10), ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2), and per 0.1 mg/m3 increase in carbon monoxide (CO) concentrations with the conditional logistic regression analysis. People living in county-level cities were more susceptible. Particularly, a significant positive association was found between air pollutant mixture exposure and suicide deaths (OR=1.04,95 % CI: 1.01, 1.06). The excess fraction of suicide deaths due to air pollution reached a maximum of 8.07 %. In conclusion, we found associations between individual and mixed ambient air pollutants and suicide deaths, informing the development of integrated air pollution management and targeted measures for suicide prevention and intervention. Environmental ImplicationAs a major contributor to the global burden of disease, air pollution was confirmed by accumulating studies to have adverse impact on mental health, and potentially lead to suicide deaths. However, systematic studies on the association between air pollution and suicide mortality are lacking. We explored the associations of multiple air pollutants and pollution mixtures with suicide deaths and assessed excess suicide mortality due to air pollution, emphasizing the importance of air pollution control on suicide prevention. Our study provides evidence to support mechanistic studies on the association between air pollution and suicide, and informs comprehensive air pollution management.

Eficiencia de los bioindicadores de toxicidad sobre contaminantes de aguas residuales industriales

In this paper, we present some important biological factors that modify the efficiency of toxicity bioindicators used to evaluate the harmful effect of industrial wastewater pollutants on biological organisms and processes, such as reproduction, growth and development. The Lactuca sativa model was analyzed and proposal for new biological parameters with fungi, bacteria, plants and animals that can be used as bioindicators of toxicity and ecotoxicity that do not directly compromise the survival of organisms in bioassays and environments contaminated with industrial wastewater effluents.

Environmental challenges and air pollution in Bac Lieu, Vietnam: assessing sources and impacts

AbstractBac Lieu, a region with diverse industries like handicrafts, agriculture, tourism, and a thriving marine economy, faces environmental challenges from climate change, resource exploitation, and rising air pollution due to vehicular, industrial, and agricultural emissions, along with waste management issues. The materials and methods employed in this study encompassed various phases critical for assessing air quality and devising an Air Quality Management Plan (AQMP) for Bac Lieu province. The AQMP framework involved activities such as baseline assessments, emission inventories, air quality monitoring, and modeling using dispersion models like AERMOD. The study proposed the application of the AirQ + model to analyze the correlation between air quality and human health, emphasizing the short-term effects of pollutants on respiratory and cardiovascular diseases, and estimating potential avoidable cases in Bac Lieu province. The emissions inventory in Bac Lieu province categorizes sources into point, mobile, and area. Major CO emissions come from waste burning, cooking, and mixed sources, while traffic significantly impacts CO levels. Residential areas show significant PM10, PM2.5, and NO2 emissions. Point sources impact nearby areas, notably in districts like Hong Dan and Phuoc Long. Cooking activities lead to high PM10 and CO emissions, especially in Bac Lieu city. Traffic emissions, particularly in urban hubs, significantly contribute to pollution, notably in Bac Lieu City, Vinh Loi, and Hoa Binh districts. Transportation emissions in urban zones contribute significantly to air pollution, while rural areas are influenced by various activities like burning, construction, and cooking, shaping diverse local air quality.

Analysis of mathematical model for asthma caused by the effects of environmental pollution

Asthma is a condition in which your airways narrow and swell and may produce extra mucus. In this study, an improved mathematical model of asthma which includes infected class not detected, infected detected class and recovered (relieved) class was formulated. The model exhibits two equilibrium, namely disease free equilibrium and endemic equilibrium. The analysis of positivity and boundedness of solutions showed that the model is epidemiologically well pose d. Simulation results showed that when pollutants are discharged into the environment at a constant rate, the asthma disease cases also increase in the population due to the fact that the interaction rate of both susceptible and infected undetected with pollutants in creases.Finally, asthma can be control by restricting the smokers from the population and the rate of release of pollutants into the environment.

Transforming capital: The role of human capital structure in modulating environmental outcomes across economic transitions

Based on the perspective of new structural economics, this study builds a theoretical framework of human capital structure and environmental pollution. Human capital structure on pollution has different manifestations at different stages of development, the effect of pollution based on human capital structure follows the environmental Kuznets curve. Using multinational panel data (1990–2015) and provincial panel data for China (2004–2020), examined the dynamic relationship between human capital structure upgrading and pollution by introducing an interaction term between human capital and economic development level, applying random-effect, fixed-effect models, and a dynamic model test. The results support our theoretical analysis.

Assessment of genotoxicity of air pollution in urban areas using an integrated model of passive biomonitoring

Atmospheric pollution is a major public health issue and has become increasingly critical for human health. Urban atmospheric pollution is typically assessed through physicochemical indicators aligned with environmental legislation parameters, providing data on air quality levels. While the effects of pollution on sensitive organisms serve as a warning for public health decision-makers, there remains a need to explore the interpretation of environmental data on pollutants. The use of species adapted to urban environments as sentinels enables continuous and integrated monitoring of environmental pollution implications on biological systems. In this study, we investigated the use of the plant species Tradescantia pallida as a biomonitor to evaluate the genotoxic effects of atmospheric pollution under diverse vehicular traffic conditions. T. pallida was strategically planted at the leading urban intersections in Uberlândia, Brazil. During COVID-19 pandemic lockdowns, we compared indicators such as physical, biological, and traffic data at different intersections in residential and commercial zones. The reduction in vehicular traffic highlighted the sensitivity of plant species to changes in air and soil pollutants. T. pallida showed bioaccumulation of heavy metals Cd and Cr in monitored areas with higher traffic levels. Additionally, we established a multiple linear regression model to estimate genotoxicity using the micronucleus test, with chromium concentration in the soil (X1) and particulate matter (PM) in the atmosphere (X2) identified as the primary independent variables. Our findings provide a comprehensive portrait of the impact of vehicular traffic changes on PM and offer valuable insights for refining parameters and models of Environmental Health Surveillance.

Association of transportation noise with cardiovascular diseases.

This comprehensive article delves into the intricate and multifaceted issue of noise pollution, shedding light on its diverse sources, profound health implications, and the economic burden it imposes on societies. Noise pollution is an increasingly prevalent environmental challenge, impacting millions of people worldwide, often without their full awareness of its adverse effects. Drawing from a wealth of scientific research, the article underscores the well-established links between noise pollution and a spectrum of health issues, including cardiovascular diseases, sleep disturbances, and psychological stress. While exploring the sources and consequences of noise pollution, the article highlights the urgent need for a holistic and collaborative approach to mitigate its impact. This entails a combination of regulatory measures, technological innovations, urban planning strategies, and public education campaigns. It is increasingly evident that the detrimental effects of noise pollution extend beyond physical health, encompassing mental and social well-being. The article also addresses the synergistic relationship between noise pollution and other environmental stressors, emphasizing the importance of considering noise in conjunction with factors like air pollution and access to green spaces. It examines the potential of green spaces to mitigate the effects of noise pollution and enhance overall health.

The impact of air pollution on household vulnerability to poverty: An empirical study from household data in China

Understanding the relationship between air pollution and poverty is essential for improving livelihoods and fostering common prosperity. While existing studies have concentrated on the impact of extreme climate and natural disasters on poverty, the adverse effects of air pollution are neglected. Using the China Family Panel Studies (CFPS) from 2016 to 2018, this study investigates air pollution's effect on household vulnerability to poverty, including the mechanisms and heterogeneity. Results shows that air pollution significantly heightens household vulnerability to poverty. This effect stems from air pollution lowering incomes and increasing healthcare burden. Heterogeneity analysis shows that air pollution negatively impacts households with low wealth, poorly educated, weak social networks, and those in developing, non-coastal, and high-terrain cities. Furthermore, air pollution more severely affects households with high consumption volatility and low wealth compared to those with low vulnerability. We also discover that the adverse effects of air pollution on household vulnerability to poverty diminish with increased physical capital. Local governments are encouraged to intensify efforts in reducing emissions through improved environmental regulations, protecting residents from pollution-induced harm.

How does heavy haze weather impact operational efficiency? An empirical study of Chinese manufacturing firms

Global warming has escalated the frequency of extreme climate events. Considering the escalating severity of air pollution, investigating its potential to cause operational problems is of value. Some studies have explored air pollution's effects from individual perspectives, including emotions, attitudes, and decision-making behaviors. Yet, the influence of heavy haze weather on firm performance from an operations management viewpoint remains uninvestigated. This study seeks to address this research gap. Utilizing a longitudinal dataset from 2255 manufacturing firms between 2014 and 2020, this study empirically examines heavy haze weather's impact on operational efficiency. Three contingency categories are identified: strategic positioning, structural contingency, and institutional factors. The findings suggest that heavy haze weather adversely impacts operational efficiency, notably for firms with cost leadership strategies and high labor productivity, whereas such effect can weaken in the firms with process standardization and governmental environment inspection. Enhancing the understanding about the effect of heavy haze weather on operational performance, these findings offer strategic insights for firms to mitigate heavy haze weather and provide empirical support for government to make environmental policy-making.

Polluted air, smarter factories? China's robot imports shed light on a potential link

Robot-centered intelligent manufacturing is leading a new round of technological revolution and industrial change. Existing studies have neglected the impact of air pollution, a non-monetary factor, on firms' intelligent manufacturing transformation (FIMT). Using matched samples from China's industrial enterprise database and China's customs database, and based on enterprises' “machine replacing human” strategy, this paper reveals the facilitating effect of air pollution on FIMT. The robustness estimation results after endogeneity treatment, replacing the core variables, changing the clustering level, removing the policy influence, avoiding the interference of domestic robots, changing the estimation strategy, and restricting the import trade mode still support the conclusion. The mechanism by which air pollution accelerates FIMT lies in the first: the factor substitution effect of rising labor costs due to air pollution. The second is the skill-capital complementarity effect due to increased firms' human capital investment induced by air pollution. The third is the intelligent investment effect due to increased economic policy uncertainty induced by air pollution. In addition, air pollution accelerates FIMT more significantly in non-state-owned firms, high labor-intensity industries, and regions with high population aging. This paper argues that there is no conflict between environmental governance and intelligent manufacturing transformation. Air pollution and “machines replacing humans” in the labor market efficiency and fairness issues need attention.