Effects of agriculture crop residue burning on children and young on PFTs in North West India

Exposure to Smoke From Wildfire, Prescribed, and Agricultural Burns Among At-Risk Populations Across Washington, Oregon, and California

Wildfires, prescribed burns, and agricultural burns all impact ambient air quality across the Western U.S.; however, little is known about how communities across the region are differentially exposed to smoke from each of these fire types. To address this gap, we quantify smoke exposure stemming from wildfire, prescribed, and agricultural burns across Washington, Oregon, and California from 2014 to 2020 using a fire type-specific biomass burning emissions inventory and the GEOS-Chem chemical transport model. We examine fire type-specific PM2.5 concentration by race/ethnicity, socioeconomic status, and in relation to the Center for Disease Control's Social Vulnerability Index. Overall, population-weighted PM2.5 concentrations are greater from wildfires than from prescribed and from agricultural burns. While we found limited evidence of exposure disparities among sub-groups across the full study area, we did observe disproportionately higher exposures to wildfire-specific PM2.5 exposures among Native communities in all three states and, in California, higher agricultural burn-specific PM2.5 exposures among lower socioeconomic groups. We also identified, for all three states, areas of significant spatial clustering of smoke exposures from all fire types and increased social vulnerability. These results provide a first look at the differential contributions of smoke from wildfires, prescribed burns, and agricultural burns to PM2.5 exposures among demographic subgroups, which can be used to inform more tailored exposure reduction strategies across sources.

Crop residue burning increased during the COVID-19 lockdown: A case study of rural India

The customary practice of crop residue burning (CRB) is a major policy concern across several developing economies because of the associated increase in air pollution and reduction in soil quality. CRB poses a hazard to public health and sustainable farmland management. We collected original survey data from a panel of 400 wheat farmers on CRB choices during April-May of 2019 and 2020 - with the latter coinciding with India's COVID-19 nationwide lockdown. This timeline of events facilitated a unique identification of changes in CRB that are attributable to the lockdown. Several studies find that lockdowns during 2020 had beneficial effects on the environment owing to reduced economic activity. However, our findings indicate that CRB may have unintentionally increased during the lockdown. A binary variable regression framework analyzes the determinants of CRB choices of farmers over two years. We control for farmers' opinions on various socioeconomic aspects of the pandemic lockdown to examine its effects on their CRB decisions. The lockdown significantly increased the likelihood of CRB by up to 12%. Furthermore, farmers who lost agricultural income and those compelled to sell assets during the lockdown were 22% and 19% more inclined, respectively, to choose CRB. Labor mobility ceased during the lockdown and increased the cost of environmentally friendly farmland management; this increased the likelihood of CRB by 6%. This study contributes to a growing literature on the unintentional consequences of pandemic lockdowns.

Health Impacts of Wildfire Smoke on Children and Adolescents: A Systematic Review and Meta-analysis

PURPOSE OF REVIEW

Wildfire smoke is associated with human health, becoming an increasing public health concern. However, a comprehensive synthesis of the current evidence on the health impacts of ambient wildfire smoke on children and adolescents, an exceptionally vulnerable population, is lacking. We conduct a systematic review of peer-reviewed epidemiological studies on the association between wildfire smoke and health of children and adolescents.

RECENT FINDINGS

We searched for studies available in MEDLINE, EMBASE, and Scopus from database inception up to October 11, 2022. Of 4926 studies initially identified, 59 studies from 14 countries were ultimately eligible. Over 33.3% of the studies were conducted in the USA, and two focused on multi-countries. The exposure assessment of wildfire smoke was heterogenous, with wildfire-specific particulate matters with diameters ≤ 2.5 µm (PM2.5, 22.0%) and all-source (22.0%) PM2.5 during wildfire period most frequently used. Over half of studies (50.6%) focused on respiratory-related morbidities/mortalities. Wildfire smoke exposure was consistently associated with enhanced risks of adverse health outcomes in children/adolescents. Meta-analysis results presented a pooled relative risk (RR) of 1.04 (95% confidence interval [CI], 0.96-1.12) for all-cause respiratory morbidity, 1.11 (95% Ci: 0.93-1.32) for asthma, 0.93 (95% CI, 0.85-1.03) for bronchitis, and 1.13 (95% CI, 1.05-1.23) for upper respiratory infection, whilst - 21.71 g for birth weight (95% CI, - 32.92 to - 10.50) per 10 µg/m3 increment in wildfire-specific PM2.5/all-source PM2.5 during wildfire event. The majority of studies found that wildfire smoke was associated with multiple adverse health outcomes among children and adolescents, with respiratory morbidities of significant concern. In-utero exposure to wildfire smoke may increase the risk of adverse birth outcomes and have long-term impacts on height. Higher maternal baseline exposure to wildfire smoke and poor family-level baseline birthweight respectively elevated risks in preterm birth and low birth weight associated with wildfire smoke. More studies in low- and middle-income countries and focusing on extremely young children are needed. Despite technological progress, wildfire smoke exposure measurements remain uncertain, demanding improved methodologies to have more precise assessment of wildfire smoke levels and thus quantify the corresponding health impacts and guide public mitigation actions.

Determinants of wheat residue burning: Evidence from India

Postharvest crop residue burning (CRB) is a major policy issue in several developing countries because of harmful environmental and public health consequences. While the literature has extensively examined the reasons for rice CRB, much less is known about wheat residue management. This paper explores the drivers of CRB of wheat in India and relates it to farmers' prior decisions related to CRB of rice in the preceding season. Using primary data on residue management practices of 301 Indian farmers, whom we tracked over two consecutive harvests of rice (2018) and wheat (2019), we find that farmers are significantly more likely to burn wheat residue if they had previously burned rice residue. The possibility of this linkage or spillover increases the likelihood of wheat residue burning by 15.6 to 21 percent. Furthermore, farmers are undertaking wheat CRB despite the positive net benefit of choosing non-burning alternatives to manage crop residue. Our results suggest that ensuring well-functioning markets for crop residue, awareness campaigns, and recognition of spillover effects of residue management across crops over time can enable policies to promote pro-environmental postharvest choices.

Agricultural burning in Imperial Valley, California and respiratory symptoms in children: A cross-sectional, repeated measures analysis

Burning of agricultural fields is an understudied source of air pollution in rural communities in the United States. Smoke from agricultural burning contains air toxics that adversely impact respiratory health. Imperial County in southeastern California is a highly productive agricultural valley that heavily employs agricultural burning to clear post-harvest crop remnants. We related individual-level exposure to agricultural burns to parent-reported respiratory symptoms in children. We leveraged the Children's Assessing Imperial Valley Respiratory Health and the Environment (AIRE) cohort of 735 predominantly Hispanic low-income elementary school students in Imperial County. Parents reported children's respiratory health symptoms and family demographic characteristics in questionnaires collected at enrollment and in annual follow-up assessments from 2017 to 2019. Permitted agricultural burns in Imperial County from 2016 to 2019 were spatially linked to children's geocoded residential addresses. We used generalized estimating equations to evaluate prevalence differences (PDs) in respiratory symptoms with increasing exposure to agricultural burning within 3 km in the 12 months prior to each assessment. Nearly half of children (346, 49 %) lived within 3 km of at least one agricultural burn in the year prior to study enrollment. In adjusted models, each additional day of agricultural burning in the prior year was associated with a one percentage point higher prevalence of wheezing (PD 1.1 %; 95 % CI 0.2 %, 2.0 %) and higher bronchitic symptoms (PD 1.0 %; 95 % CI -0.2 %, 2.1 %). Children exposed to four or more days of burning had an absolute increased prevalence of wheezing and bronchitic symptoms of 5.9 % (95 % CI -0.3 %, 12 %) and 5.6 % (95 % CI -1.8 %, 13 %), respectively, compared to no burn exposure. Associations with wheezing were stronger among children with asthma (PD 14 %; 95 % CI -1.4 %, 29 %). To our knowledge, this is the first U.S. study of agricultural burning and children's respiratory health. This work suggests that reducing agricultural burning could improve children's respiratory health.

Respiratory and allergic health effects in children living near agriculture: A review

BACKGROUND

Exposure to pesticides and agricultural burning are likely to co-occur in agricultural communities, but these exposures have remained distinct bodies of research. We reviewed epidemiological studies to identify the respiratory health effects of children exposed to pesticides and agricultural burning through a systematic evaluation of peer-reviewed publications of children living in industrial agricultural areas.

METHODS

Two academic search databases (PubMed and Scopus) were queried for all available studies published in English before May 31st, 2021. The initial search combining both exposure metrics (pesticides and agricultural burning) yielded zero publications and thus the queries were performed and presented separately.

RESULTS

Studies were categorized based on main exposure of interest (i.e., pesticides or agricultural burning) and by respiratory health outcome assessment (i.e., self-reported asthma, acute respiratory symptoms, and lung function measurements). In total we identified 25 studies that focused on pesticide exposures and children's respiratory health, and 12 studies that focused on exposure to agricultural burning and children's respiratory health. A majority of the pesticide studies (18/25) reported a positive association between exposure to pesticides and adverse childhood respiratory health effects. Similarly, most (11/12) of the agricultural burning studies also reported a positive association between exposure to agricultural burning and adverse respiratory health effects.

CONCLUSION

The most frequently studied health outcomes in these publications were acute respiratory symptoms (n = 11 pesticides, n = 3 agricultural burning), followed by asthma (n = 9 pesticides, n = 3 agricultural burning), and lung function measurements (n = 5 pesticides, n = 6 agricultural burning). Although health outcome assessment differed between pesticide studies and agricultural burning studies, similar adverse respiratory health effects were observed across the majority of studies.

Crop residue burning in South Asia: A review of the scale, effect, and solutions with a focus on reducing reactive nitrogen losses

This paper reviews the literature on crop residue burning - a widespread practice in many regions in South Asia. Specifically, we examine evidence from studies highlighting the scale of the practice in South Asia, the environmental implications, the drivers of the practice and the remedies to the problem. The studies provide evidence that the Indo-Gangetic Plain (IGP) is a hot-spot for atmospheric pollutants, with seasonal crop residue burning being a major contributor. The burning of crop residue is reported to degrade the soil, increase the risk of erosion, and increase the soil temperature, consequently decimating soil microorganisms. This subsequently impacts the monetary cost involved in recovering the soil fertility and the potential for further pollution through the increased use of fertilizer. The review shows that farmers' reasons for burning crop residues are mainly the high cost of incorporating, collecting, transporting, and processing crop residues in South Asia. Labour shortages, the marketability of the crop residue and the short time interval between harvest and next cropping seasons also influence farmers decision to burn crop residue. To address this problem, there is the need to encourage the use of agricultural machines capable of sowing crops in standing stubble, adopting in-situ practices and changing crop varieties to those with short duration. In addition, education and awareness are needed to change beliefs and perceptions on crop residue burning. Crucially, when promoting alternative sustainable uses of crop residue, the economic benefits should be prioritized, and support towards initial investments that accompany the adoption of alternative practices should be provided.

Towards a clean production by exploring the nexus between agricultural ecosystem and environmental degradation using novel dynamic ARDL simulations approach

Agriculture, which serves as a lifeline for us, is unequivocally vital for an agriculture-dependent economy like Bangladesh, not only for its food supply but also because of its significant contribution towards achieving Sustainable Development Goals (SDGs) 1 and 2. However, in a third-world nation like Bangladesh, where farming practices largely circumvent the environmental consequences, raised our concern. In this milieu, this study is a novel attempt to explore the association between agricultural ecosystem and environmental degradation in Bangladesh using a long time spanning from 1972 to 2018. We observed a long-run association between the agroecosystem and CO₂ emission. Further, findings from the dynamic autoregressive distributed lag (DARDL) simulation model revealed that the environmental quality of Bangladesh is heavily distorted by total cereal production, total livestock head, enteric methane emissions, N₂O emissions from manure application, and CO₂ equivalent N₂O emissions from synthetic fertilizers in the short and long run, whereas agricultural technology, pesticide use in agriculture, and burned biomass crop residue deteriorated the environmental quality only in the long run. The counterfactual diagram entailed from the DARDL model projected the trend of CO₂ emission in response to positive and negative changes in the analyzed variables. Lastly, this study established a causal relationship between the agroecosystem and environmental degradation using frequency domain causality. Indeed, our study will aid in reshaping agricultural practices in an eco-friendly manner to mitigate environmental degradation and help formulate pragmatic policy actions so that agro-lead nations can thrive in the race of achieving SDGs 1, 2, and 13.

Preventable mortality attributable to exposure to air pollution at the rural district of Punjab, India

Air pollution has emerged as a leading global health risk in recent decades, where its health impacts are primarily focused on urban areas. In India, semi-urban and rural areas are also emerging as air pollution hotspots. As these regions are out of focus, the current study monitored air pollution (PM_2.5) at a rural district of Punjab in North India and attempted to study the associated health impacts. Hospital data of outpatient department (OPD), inpatient department (IPD) and all-cause mortality was correlated with change in PM_2.5 concentrations. PM_2.5 concentrations showed seasonal variations having relatively higher concentrations during post-monsoon and winter seasons. This rise in air pollution (annual average 92 µg/m³) was found to be mainly due to crop residue burning, including local meteorology. In comparison, hospital data shows that hospital visits and admissions were higher during monsoon. This shows that hospital admissions could not be directly linked to air pollution in rural areas as other factors such as short days during winters and self-medication, socio-economic factors and dependency on local unauthorised traditional healers may influence. The application of the AirQ + model for short-term health effects reveals that out of 2582 total deaths, preventable deaths ranging from 246 (WHO guidelines value - 10 µg/m³) to 159 (Indian NAAQS - 40 µg/m³) could be ascribed to air pollution exposure and specifically PM_2.5. However, these deaths are avoidable by developing strategies to minimise air pollution in rural areas. Hence, a comprehensive approach is needed to plan air pollution reduction strategies, including urban, semi-urban and rural areas.

Understanding seasonal variation in ambient air quality and its relationship with crop residue burning activities in an agrarian state of India

In India, Indo-Gangetic Plains (IGP) is becoming the hotspot of air pollution due to increasing anthropogenic activities such as rapid industrial growth, infrastructure development, transportation activities, and seasonal practice of crop residue burning. In the current study, seasonal variation in ambient air quality for 14 parameters, i.e., particulate matter (PM), trace gases, and volatile organic compounds (VOCs), along with meteorological parameters, was studied in 21 districts of the Haryana state for year 2019, situated in IGP. To analyze spatial variation of pollutants, ambient air quality data of 23 continuous ambient air quality monitoring stations were divided into three zones based on ecology and cropping pattern. All the zones showed annual mean PM₁₀ and PM_2.5 concentrations much higher than national ambient air quality standards. Annual mean PM₁₀ concentration (±standard deviation) in Zones-1, 2, and 3 was 156±86, 174±93, and 143±74 μg m^-3, whereas for PM_2.5 was 71±44, 85±54, and 78±47 μg m^-3. The results showed a considerable seasonal variation in the concentration of all pollutants. Most of the pollutants peak in the post-monsoon season, followed by winters in which crop residue burning predominates in many parts of the Haryana. PM₁₀ concentrations increased by 65-112% and PM_2.5 concentrations increased by 131-147% in the post-monsoon season compared to monsoons. The post-monsoon season showed the highest concentration of PM₁₀, NO, and toluene (Zone-1); and PM_2.5, NH₃, CO, and benzene (Zone-2); whereas in winters, SO₂ (Zone-1); ethylbenzene, m,p-xylene, and xylene (Zone-2); and NO₂ and NOx (Zone-3) showed the maximum pollution levels. The O₃ concentration was highest in the pre-monsoon season (Zone-1). The satellite-based fire counts and PCA results show a significant influence of crop residue burning in the post-monsoon season and solid biomass burning in winters on Haryana's air quality. The study could help to understand seasonal variation in ambient air quality and the influence of factors such as crop residue burning in the IGP region, which could help to formulate season-specific control measures to improve regional air quality.

Determinants of crop residue burning practice in the Terai region of Nepal

The open burning of agricultural crop residue is a key environmental issue facing the Hindu Kush Himalaya region, the Indo-Gangetic plain in particular. There is a varying intensity in the incidence of open agricultural burning in this region, and multiple drivers that determine why farmers in this region decide to burn their crop residues. While there have been research studies conducted for other countries in the region, research into the determinants of crop-burning in the Nepalese context is missing. Using primary data from a survey of 388 farming households across three districts of the Nepal Terai―Nawalparasi, Rupandehi and Kapilvastu―applying a recursive bivariate probit model, this study seeks to find out what drives the Nepalese farmers to burn their crop residue instead of using them in a sustainable manner and suggest policy recommendations for mitigation. Our findings show that the major determining factors that influence the farmers’ behavior in Nepal are livestock ownership, combine harvester use and awareness level of the farmers. While the effects of crop residue burning is transboundary in nature, the mitigation measures require to be region specific. Based on the findings, the study proposes raising livestock, using technology like Happy Seeders or upgrade the combine harvesters, raising awareness and changing perception of farmers, and promoting alternative uses of crop residue as viable mitigation measures.

Enhanced adsorptive removal of sulfamethoxazole from water using biochar derived from hydrothermal carbonization of sugarcane bagasse

This research work primarily focussed on the production of biochar from sugarcane bagasse through HTC followed by NaOH activation at inert atmosphere for removing SMX from water. The biochar was characterized for structural morphology and presence of functional groups. XRD and FTIR analysis confirmed that presence of aromatized graphitic structure accumulated with oxygenated functional groups are responsible for the elimination of SMX. SEM analysis portrayed the sphere-shaped structure of biochar with hydrophobic groups interior and hydrophilic groups exterior. BET isotherm revealed the active surface area equal to 1099 m²/g with high coverage of mesopores structure. P_zpc of adsorbent is evaluated to 6.5 stating that effective removal of SMX depends on ionization effects induced due to reaction medium. Kinetics study revealed the sorption of SMX followed chemical interaction pertaining to Elovich model. Isotherm studies revealed that Freundlich model fitted well stating heterogeneous mode of interaction. Immobilization of SMX on surface of ABC is due to charge assisted hydrogen bonding and π-π interaction with graphitized carbon, showing maximum sorption capacity of 400 mg/g through spontaneous reaction. The results suggested that HTC derived biochar had great adsorption affinity with respect to pH towards SMX and could be employed as an effective sorbent in cleaning water contaminants.

Statistical interpretation of environmental influencing parameters on COVID-19 during the lockdown in Delhi, India

The novel coronavirus disease is known as COVID-19, which is declared as a pandemic by the World Health Organization during March 2020. In this study, the COVID-19 connection with various weather parameters like temperature, wind speed, and relative humidity is investigated and the future scenario of COVID-19 is predicted based on the Gaussian model (GM). This study is conducted in Delhi, the capital city of India, during the lowest mobility rate due to strict lockdown nationwide for about two months from March 15 to May 17, 2020. Spearman correlation is applied to obtain the interconnection of COVID-19 cases with weather parameters. Based on statistical analysis, this has been observed that the temperature parameter shows a significant positive trend during the period of study. The number of confirmed cases of COVID-19 is fitted with respect to the number of days by using the Gaussian curve and it is estimated on the basis of the model that maximum cases will go up to 123,886 in number. The maximum number of cases will be observed during the range of 166 ± 36 days. It is also estimated by using the width of the fitted GM that it will take minimum of 10 months for the complete recovery from COVID-19. Additionally, the linear regression technique is used to find the trend of COVID-19 cases with temperature and it is estimated that with an increase in temperature by 1 °C, 30 new COVID-19 cases on daily basis will be expected to observe. This study is believed to be a preliminary study and to better understand the concrete relationship of coronavirus, at least one complete cycle is essential to investigate. The laboratory-based study is essential to be done to support the present field-based study. Henceforth, based on preliminary studies, significant inputs are put forth to the research community and government to formulate thoughtful strategies like medical facilities such as ventilators, beds, testing centers, quarantine centers, etc., to curb the effects of COVID-19.

Does the prevailing Indian agricultural ecosystem cause carbon dioxide emission? A consent towards risk reduction

Recently, due to the increasing concentration of carbon dioxide emissions in the atmosphere, the global environment has changed dramatically. As a result, climate change, global warming, and environmental degradation-like issues have been raised. Presumably, human beings, as well as the agricultural ecosystem, become most vulnerable to these issues. In this context, the study focuses on the nexus between Indian's agricultural ecosystem and carbon dioxide emission. For the purpose of this study, annual time series data over the time span from 1990 to 2014 was used. The modern techniques, for instance, Johansen, ARDL, and Granger causality, were employed. The Johansen test and ARDL model suggest that carbon dioxide emissions and agricultural ecosystems are co-integrated. In the short run, the ARDL model suggests that a 1% increase in biomass-burned crop residues, total pesticides, and stock of livestock would increase carbon dioxide emissions by 0.26, 0.3, and 6.58% respectively. The residual diagnostics tests suggest that the ARDL model is stable, reliable, and credible in the present form. The results of the granger causality show that a unidirectional causality was found between carbon dioxide and total heads of livestock, all animal manure applied to the soil, agricultural technology, and total pesticide used in the agricultural sector. In contrast, bidirectional causality was found between the production of biomass-burned crop residues and carbon dioxide emission. Therefore, it is suggested that the government should take preemptive action to reduce the risk of environmental pollution and degradation through synchronized strategies particularly by reducing the amount of biomass-burned crop residues and usage of total pesticides in the country.

A mixed-methods community-based participatory research to explore stakeholder's perspectives and to quantify the effect of crop residue burning on air and human health in Central India: study protocol

Background

Crop residue burning adversely affects air quality and consequently human health. India, being one of the largest agro-economies of the world, produces around 500 Million tonnes of crop residue annually most of which is burnt on-farm. However, integrated studies that simultaneously quantify the effects of crop residue burning while exploring the subjective determinants of the practice are lacking in India. This paper describes the protocol for a longitudinal mixed methods research study employing a community-based participatory approach to fill this gap.

Methods

Both quantitative and qualitative data will be collected in a rural setting of the central Indian province of Madhya Pradesh, over 1 year. A steering committee comprising of the research team and community representatives will be formed. The proportion of cultivable land burnt in one crop burning season will be estimated. The association between crop residue burning, level of ambient air pollutants, and pulmonary function of village residents will be determined. Focus groups, interviews, and participatory rural appraisal methods will be used to explore stakeholder perspectives about crop residue burning. Potential barriers and opportunities for substituting burning with an alternative crop residue management technique will be ascertained as the basis for future interventions. Ethics approval has been obtained from the Institutional Ethics Committee of the National Institute for Research in Environmental Health (No: NIREH/BPL/IEC/2019–20/1494, dt 06/01/2020).

Discussion

This manuscript describes the protocol for a novel community-based participatory study to investigate thoroughly the phenomenon of crop residue burning from the perspective of the agricultural community through their active collaboration. The lack of comprehensive evidence regarding the factors responsible for crop residue burning in India underlines the importance of implementing this study protocol to fill in this critical gap in knowledge. While acknowledging that findings of this study will be not generalizable to agricultural communities other than the one studied, it is expected that the study will generate baseline evidence that might be beneficial in developing and implementing an appropriate intervention strategy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-020-09844-6.

A high-resolution emission inventory of air pollutants from primary crop residue burning over Northern India based on VIIRS thermal anomalies

Emissions from the crop residue burning adversely affect the regional and global air quality including public health. In this study, a district-wise comprehensive emission inventory of key pollutants (PM_2.5, PM₁₀, CO, CO₂, SO₂, NOx, N₂O, NH₃, CH₄, NMVOC, EC, OC, PAH) emitted during primary crop residue burning was developed using activity data for the major agrarian states of north India for the agricultural year 2017-18. The emissions were scaled to the spatial resolution of 1 km grid to study the spatial distribution of crop residue burning activities using VIIRS Thermal anomalies datasets. An estimated 20.3 Mt and 9.6 Mt of crop residue were burned in Punjab and Haryana, resulting in an emission of 137.2 Gg and 56.9 Gg of PM_2.5 and 163.7 Gg and 72.1 of PM₁₀ Gg for respective states. The emissions of EC, OC, and PAHs were 8.6 Gg, 45.7 Gg, and 0.08 Gg in Punjab, whereas in Haryana emissions were 3.7 Gg, 17.7 Gg, and 0.03 Gg, respectively. The results show that rice and wheat crops were major contributor to residue burnt at the field (>90%) leading to the high load of atmospheric emissions in the IGP region. Further, CO₂ equivalent greenhouse gas emissions were 34.8 Tg and 17.3 Tg for Punjab and Haryana, respectively. Around 30000 and 8500 active fires were detected by VIIRS over the agricultural area of Punjab and Haryana during the studied year. The GIS-based bottom-up approach using gridded emission inventory shows pollutant distribution dominates over the south-western part of Punjab and north-western region of Haryana. The proximity of these regions to Delhi and transboundary movement of emissions towards Indo-Gangetic plains causes high air pollution episodes. The high-resolution inventory of various pollutants will be useful for regional air quality models to better predict and manage the hotspot of air pollution.

Emission inventories of rice straw open burning in the Red River Delta of Vietnam: Evaluation of the potential of satellite data

Although rice straw open burning is one of the main sources of air pollution in Asian countries, problems remain in collecting the activity data needed to calculate emission inventories. In Vietnam, the results from traditional data collection methods, which are reported by the Vietnam General Statistics Office high levels of uncertainty. This is largely due to a lack of human and financial resources. To improve upon this, this study critically assessed the benefits of incorporating cultivation area data obtained by the Sentinel-1 Synthetic Aperture Radar (SAR) satellite in combination with crop production records during the period of 2015-2017. The results suggested that incorporating remote sensing data, especially satellite data, into a process-based crop model can improve the spatial distribution of yield estimates. Satellite data for 2018 were also applied to estimate emissions from rice straw open burning in the Red River Delta, Vietnam, for which official statistics are not otherwise yet available. The results show that a total of 3.24 Mt of burnt rice straw produced 3.82 Mt of CO₂, 301 Gg of CO, 29.5 Gg of PM₁₀, and 27 Gg of PM_2.5. The estimated emission amounts for the common air pollutants SO₂, NO_x, and NH₃ were 583 tonnes, 7.4 Gg, and 13.3 Gg, respectively. Hydrocarbon emissions were 31 Gg for CH₄ and 22.7 Gg for NMVOC. The emission of BC, which is one of the main short-lived climate forcers, totalled 1.6 Gg. Based on these results, satellite data demonstrate great potential for estimating emissions from rice croplands, having the advantages of timely availability and cost competitiveness.

Crop burning and the prevalence of asthma and COPD emergency department treatments in a rural Arkansas county

OBJECTIVE

To evaluate the impact of crop burning on the prevalence of asthma and COPD emergency department (ED) treatments in a rural Arkansas county.

METHODS

Administrative datasets listing ED treatments for asthma and COPD obtained from the Arkansas Hospital Discharge Dataset System for the calendar years 2014-2016 were used in this semi-ecological study. Primary diagnosis codes (ICD-9: 490-496 and ICD-10: J40-J47) were used to identify patients who were diagnosed with asthma and COPD. Patients with a reported county of residence in Craighead County were determined as case county residents and those in Sebastian County were control county residents. Month of visit was used to determine seasonal variation. PM 2.5 air quality data were obtained from the EPA AQS Data Mart.

RESULTS

Between 2014 through 2016, there were a combined total of 2,536 ED treatments due to asthma and 8,530 due to COPD in Craighead and Sebastian counties. The odds of being treated in the ED during the fall months for asthma and COPD are associated with a 20.9% increase and 16.9% increase respectively in Craighead County as compared to Sebastian Country after adjusting for potential confounders (p = 0.04, p = 0.003). PM 2.5 concentrations were higher in Craighead County than Sebastian County during the fall season (p = 0.005).

CONCLUSION

Fall ED treatments for asthma and COPD were higher in Craighead County, Arkansas compared to Sebastian County, Arkansas for the years 2014-2016. PM 2.5 levels were also higher in Craighead County in the fall during these years. These differences may be attributable to crop burning.​.

Real-time monitoring of air pollutants in seven cities of North India during crop residue burning and their relationship with meteorology and transboundary movement of air

Air pollutants emissions due to the burning of crop residues could adversely affect human health, environment, and climate. Hence, a multicity campaign was conducted during crop residue burning period in Indo Gangetic Plains (IGP) to study the impact on ambient air quality. Seventeen air pollutants along with five meteorological parameters, were measured using state of the art continuous air quality monitors. The average concentration of PM₁₀, PM_2.5, and PM₁ during the whole campaign were 196.7±30.6, 148.2±20, and 51.2±8.9 μgm^-3 and daily average concentration were found several times higher than national ambient air quality standards for 24h. Amritsar had the highest average concentration of PM_2.5 (178.4±83.8 μgm^-3) followed by Rohtak and Sonipat (158.4±79.8, 156.5±105.3μgm^-3), whereas Chandigarh recorded the lowest concentration (112.3±6.9μgm^-3). The concentration of gaseous pollutants NO, NO₂, NO_x, and SO₂ were also observed highest at Amritsar location, i.e., 6.6±2.6ppb, 6.2±0.7ppb, 12.7±3.0ppb, and 7.5±3.3ppb respectively. The highest average O₃ and CO were 22.5±19.3ppb and 1.5±1.2ppm during the campaign. The level of gaseous pollutants and Volatile organic compounds (VOCs) found to be elevated during the campaign, which can play an important role in the formation of secondary air pollutants. The correlation of meteorology and air pollutants was also studied, and O₃ shows a significant relation with temperature and UV (R=0.87 and 0.74) whereas VOCs shows a significant correlation with temperature (R=-0.21 to -0.47). Air quality data was also analyzed to identify sources of emissions using principal component analysis, and it identifies biomass burning and vehicular activities as major sources of air pollution.

Agriculture Crop Residue Burning and Its Consequences on Respiration Health of School-Going Children

Crop waste burning in open fields is a matter of concern in relation to health-related complications in humans of all age groups, especially children. An epidemiological study was been done on school children to estimate the decline in their physiological parameters due to crop residue burning activity. A total of 150 children were inspected for 3 years (2013-2016) at 3 different sites in India. During sampling periods, spirometric tests, ambient particulate matter having size ≥10 µg-3 and ≥2.5 µg-3, and other covariates were measured twice in a fortnight. After adjustment of data in multivariate mixed-effect model, prediction and statistical analyses were done. From results obtained, it has been observed that season wise, the level of fine particulate matter (PM10 and PM2.5) was higher in rice crop residue burning seasons than in wheat crop residue burning seasons by 87% to 123% than permitted monthly limits. As per dose-response relationship, maximum degradation was observed in forced vital capacity (-7.62%) and peak expiratory flow (-6.23%) parameters from their baseline values due to burning activities. Prediction equations have been purposed to observe the future trends in physiological parameters of children. Based on Tiffeneau index, an unrecoverable effect was seen in lung parameters. Trends were alarming and may cause serious complications in early age of humans.

Risk of acute respiratory infection from crop burning in India: estimating disease burden and economic welfare from satellite and national health survey data for 250 000 persons

BACKGROUND

Respiratory infections are among the leading causes of death and disability globally. Respirable aerosol particles released by agricultural crop-residue burning (ACRB), practised by farmers in all global regions, are potentially harmful to human health. Our objective was to estimate the health and economic costs of ACRB in northern India.

METHODS

The primary outcome was acute respiratory infection (ARI) from India's fourth District Level Health Survey (DLHS-4). DLHS-4 data were merged with Moderate-Resolution Imaging Spectroradiometer satellite data on fire occurrence. Mutually adjusted generalized linear models were used to generate risk ratios for risk factors of ARI. Overall disease burden due to ACRB was estimated in terms of disability-adjusted life years.

RESULTS

Seeking medical treatment for ARI in the previous 2 weeks was reported by 5050 (2%) of 252 539 persons. Living in a district with intense ACRB-the top quintile of fires per day-was associated with a 3-fold higher risk of ARI (mutually adjusted risk ratio 2.99, 95% confidence interval 2.77 to 3.23) after adjustment for socio-demographic and household factors. Children under 5 years of age were particularly susceptible (3.65, 3.06 to 4.34 in this subgroup). Additional ARI risk factors included motor-vehicle congestion (1.96, 1.72 to 2.23), open drainage (1.91, 1.73 to 2.11), cooking with biomass (1.73, 1.58 to 1.90) and living in urban areas (1.35, 1.26 to 1.44). Eliminating ACRB would avert 14.9 million disability-adjusted life years lost per year, valued at US$152.9 billion over 5 years.

CONCLUSIONS

Investments to stop crop burning and offer farmers alternative crop-residue disposal solutions are likely to improve population-level respiratory health and yield major economic returns.

Rice-Residue Management Practices of Smallholder Farms in Vietnam and Their Effects on Nutrient Fluxes in the Soil-Plant System

In Vietnam, approximately 39 million tons of rice (Oryza sativa) residues accrue every year. In this study, we quantified soil nutrient balances of paddy rice fields under different crop-residue management practices in northern Vietnam. On twelve farms, we calculated nutrient balances for the four prevalent rice-residue management practices, i.e., (1) direct incorporation of rice residues into the soil, (2) application of rice-residue compost, (3) burning of rice residues on the field, and (4) the use of rice residues as fodder for livestock. Soils under practices (1) to (3) showed a positive nutrient balance, which indicates that soil fertility can be maintained under these practices and that the amounts of chemical fertilizers can be considerably reduced. If not, there is a risk of eutrophication in the surrounding surface waterbodies. Practice (4), in contrast, resulted in a negative nutrient balance, which indicates the need for returning nutrients to the soils. From our findings we conclude that knowledge about the effects of rice-residue management practices on nutrient cycles may help to optimize the use of fertilizers, resulting in a more sustainable form of agriculture.

Characteristics of indoor air pollution and estimation of respiratory dosage under varied fuel-type and kitchen-type in the rural areas of Telangana state in India

Indoor Air Pollution (IAP) is one of the top environmental risks in developing countries including India, with more than a million deaths annually, predominantly through Particulate Matter (PM) exposure. The current study deals with the measurement of PM concentrations in rural households under varied fuel and kitchen-types, evaluation of the indoor air pollution (IAP) characteristics and estimation of respiratory dosage for the different subjects (women, young children and the elderly). Monitoring of particulate matter (PM) was carried out during summer, monsoon and winter season with biomass, LPG and combine of biomass and LPG being used as fuel for cooking. Furthermore, different types of indoor kitchens (with partition and without partition) and outdoor kitchens (separate enclose kitchen and open kitchen) were also considered as kitchen type along with fuel are two crucial factors contributing to IAP. Deposition fractions were calculated using Multiple Particle Path Dosimetry (MPPD) to study the deposition patterns in different parts of the human respiratory tract (HRT) - head, tracheobronchial and pulmonary for women, young children and the elderly people. Dosage of particulate matter was calculated by inputting the recorded PM measurements, a comparison made for biomass-LPG and dosage intensification due to the kitchen-type presented. While the biomass households exhibited high levels of dosage (1181.4 to 5891.7 μg) against the LPG households (89.9 to 811.2 μg), the indoor kitchen types exhibited a maximum intensification of 10.6 times than outdoor kitchens with the same fuel. This study not only establishes the IAP characteristics but also quantifies the role of fuel-type and kitchen-type in IAP. The study also indicates various measures that could be deployed to reduce dosage and thus minimize the health risks.

Impact of Maternal Air Pollution Exposure on Children's Lung Health: An Indian Perspective

Air pollution has become an emerging invisible killer in recent years and is a major cause of morbidity and mortality globally. More than 90% of the world’s children breathe toxic air every day. India is among the top ten most highly polluted countries with an average PM₁₀ level of 134 μg/m³ per year. It is reported that 99% of India’s population encounters air pollution levels that exceed the World Health Organization Air Quality Guideline, advising a PM_2.5 permissible level of 10 μg/m³. Maternal exposure to air pollution has serious health outcomes in offspring because it can affect embryonic phases of development during the gestation period. A fetus is more prone to effects from air pollution during embryonic developmental phases due to resulting oxidative stress as antioxidant mechanisms are lacking at that stage. Any injury during this vulnerable period (embryonic phase) will have a long-term impact on offspring health, both early and later in life. Epidemiological studies have revealed that maternal exposure to air pollution increases the risk of development of airway disease in the offspring due to impaired lung development in utero. In this review, we discuss cellular mechanisms involved in maternal exposure to air pollution and how it can impact airway disease development in offspring. A better understanding of these mechanisms in the context of maternal exposure to air pollution can offer a new avenue to prevent the development of airway disease in offspring.

Existing agricultural ecosystem in China leads to environmental pollution: an econometric approach

Sustainable agriculture ensures food security and prevents starvation. However, the need to meet the increasing food demands of the growing population has led to poor and unsustainable agricultural practices, which promote environmental degradation. Given the contributions of agricultural ecosystems to environmental pollution, we investigated the impact of the agricultural ecosystem on environmental pollution in China using time series data from 1960 to 2014. We employed several methods for econometric analysis including the unit root test, Johansen test of cointegration, Granger causality test, and vector error correction model. Evidence based on the long-run elasticity indicates that a 1% increase in the emissions of carbon dioxide (CO₂) equivalent to nitrous oxide from synthetic fertilizers will increase the emissions of CO₂ by 1.52% in the long run. Similarly, a 1% increase in the area of harvested rice paddy, cereal production, biomass of burned crop residues, and agricultural GDP will increase the carbon dioxide emissions by 0.85, 0.63, 0.37, and 0.22%, respectively. The estimated results indicate that there are long-term equilibrium relationships among the selected variables considered for the agricultural ecosystem and carbon dioxide emissions. In particular, we identified bidirectional causal associations between CO₂ emissions, biomass of burned crop residues, and cereal production. Graphical abstract ᅟ.

Use of spatiotemporal characteristics of ambient PM2.5 in rural South India to infer local versus regional contributions

This study uses spatiotemporal patterns in ambient concentrations to infer the contribution of regional versus local sources. We collected 12 months of monitoring data for outdoor fine particulate matter (PM_2.5) in rural southern India. Rural India includes more than one-tenth of the global population and annually accounts for around half a million air pollution deaths, yet little is known about the relative contribution of local sources to outdoor air pollution. We measured 1-min averaged outdoor PM_2.5 concentrations during June 2015-May 2016 in three villages, which varied in population size, socioeconomic status, and type and usage of domestic fuel. The daily geometric-mean PM_2.5 concentration was ∼30 μg m^-3 (geometric standard deviation: ∼1.5). Concentrations exceeded the Indian National Ambient Air Quality standards (60 μg m^-3) during 2-5% of observation days. Average concentrations were ∼25 μg m^-3 higher during winter than during monsoon and ∼8 μg m^-3 higher during morning hours than the diurnal average. A moving average subtraction method based on 1-min average PM_2.5 concentrations indicated that local contributions (e.g., nearby biomass combustion, brick kilns) were greater in the most populated village, and that overall the majority of ambient PM_2.5 in our study was regional, implying that local air pollution control strategies alone may have limited influence on local ambient concentrations. We compared the relatively new moving average subtraction method against a more established approach. Both methods broadly agree on the relative contribution of local sources across the three sites. The moving average subtraction method has broad applicability across locations.

Understanding the Influence of Crop Residue Burning on PM2.5 and PM10 Concentrations in China from 2013 to 2017 Using MODIS Data

In recent years, particulate matter (PM) pollution has increasingly affected public life and health. Therefore, crop residue burning, as a significant source of PM pollution in China, should be effectively controlled. This study attempts to understand variations and characteristics of PM₁₀ and PM_2.5 concentrations and discuss correlations between the variation of PM concentrations and crop residue burning using ground observation and Moderate Resolution Imaging Spectroradiometer (MODIS) data. The results revealed that the overall PM concentration in China from 2013 to 2017 was in a downward tendency with regional variations. Correlation analysis demonstrated that the PM₁₀ concentration was more closely related to crop residue burning than the PM_2.5 concentration. From a spatial perspective, the strongest correlation between PM concentration and crop residue burning existed in Northeast China (NEC). From a temporal perspective, the strongest correlation usually appeared in autumn for most regions. The total amount of crop residue burning spots in autumn was relatively large, and NEC was the region with the most intense crop residue burning in China. We compared the correlation between PM concentrations and crop residue burning at inter-annual and seasonal scales, and during burning-concentrated periods. We found that correlations between PM concentrations and crop residue burning increased significantly with the narrowing temporal scales and was the strongest during burning-concentrated periods, indicating that intense crop residue burning leads to instant deterioration of PM concentrations. The methodology and findings from this study provide meaningful reference for better understanding the influence of crop residue burning on PM pollution across China.

Source apportionment of PM2.5 in North India using source-oriented air quality models

In recent years, severe pollution events were observed frequently in India especially at its capital, New Delhi. However, limited studies have been conducted to understand the sources to high pollutant concentrations for designing effective control strategies. In this work, source-oriented versions of the Community Multi-scale Air Quality (CMAQ) model with Emissions Database for Global Atmospheric Research (EDGAR) were applied to quantify the contributions of eight source types (energy, industry, residential, on-road, off-road, agriculture, open burning and dust) to fine particulate matter (PM_2.5) and its components including primary PM (PPM) and secondary inorganic aerosol (SIA) i.e. sulfate, nitrate and ammonium ions, in Delhi and three surrounding cities, Chandigarh, Lucknow and Jaipur in 2015. PPM mass is dominated by industry and residential activities (>60%). Energy (∼39%) and industry (∼45%) sectors contribute significantly to PPM at south of Delhi, which reach a maximum of 200 μg/m³ during winter. Unlike PPM, SIA concentrations from different sources are more heterogeneous. High SIA concentrations (∼25 μg/m³) at south Delhi and central Uttar Pradesh were mainly attributed to energy, industry and residential sectors. Agriculture is more important for SIA than PPM and contributions of on-road and open burning to SIA are also higher than to PPM. Residential sector contributes highest to total PM_2.5 (∼80 μg/m³), followed by industry (∼70 μg/m³) in North India. Energy and agriculture contribute ∼25 μg/m³ and ∼16 μg/m³ to total PM_2.5, while SOA contributes <5 μg/m³. In Delhi, industry and residential activities contribute to 80% of total PM_2.5.

The causal nexus between carbon dioxide emissions and agricultural ecosystem-an econometric approach

Achieving a long-term food security and preventing hunger include a better nutrition through sustainable systems of production, distribution, and consumption. Nonetheless, the quest for an alternative to increasing global food supply to meet the growing demand has led to the use of poor agricultural practices that promote climate change. Given the contribution of the agricultural ecosystem towards greenhouse gas (GHG) emissions, this study investigated the causal nexus between carbon dioxide emissions and agricultural ecosystem by employing a data spanning from 1961 to 2012. Evidence from long-run elasticity shows that a 1 % increase in the area of rice paddy harvested will increase carbon dioxide emissions by 1.49 %, a 1 % increase in biomass-burned crop residues will increase carbon dioxide emissions by 1.00 %, a 1 % increase in cereal production will increase carbon dioxide emissions by 1.38 %, and a 1 % increase in agricultural machinery will decrease carbon dioxide emissions by 0.09 % in the long run. There was a bidirectional causality between carbon dioxide emissions, cereal production, and biomass-burned crop residues. The Granger causality shows that the agricultural ecosystem in Ghana is sensitive to climate change vulnerability.

Exposure to particulate matter in India: A synthesis of findings and future directions

Air pollution poses a critical threat to human health with ambient and household air pollution identified as key health risks in India. While there are many studies investigating concentration, composition, and health effects of air pollution, investigators are only beginning to focus on estimating or measuring personal exposure. Further, the relevance of exposures studies from the developed countries in developing countries is uncertain. This review summarizes existing research on exposure to particulate matter (PM) in India, identifies gaps and offers recommendations for future research. There are a limited number of studies focused on exposure to PM and/or associated health effects in India, but it is evident that levels of exposure are much higher than those reported in developed countries. Most studies have focused on coarse aerosols, with a few studies on fine aerosols. Additionally, most studies have focused on a handful of cities, and there are many unknowns in terms of ambient levels of PM as well as personal exposure. Given the high mortality burden associated with air pollution exposure in India, a deeper understanding of ambient pollutant levels as well as source strengths is crucial, both in urban and rural areas. Further, the attention needs to expand beyond the handful large cities that have been studied in detail.

Spatial distribution of pollutant emissions from crop residue burning in the Punjab and Sindh provinces of Pakistan: uncertainties and challenges

Emissions of gaseous and particulate pollutants from burning of wheat straw, rice straw, cotton straw, and bagasse were studied for the two agricultural-activity-dominated provinces of Pakistan: the Punjab and Sindh. Emission estimates, inventory, and allocation maps indicated distinct patterns of pollutant emissions in the two provinces. Comparative pollutant emission analysis revealed that the Punjab province produced higher pollutants from agricultural biomass burning than Sindh province. Total emissions from these two provinces were estimated to be 16,084.04 Gg (16.08 Tg) for the year 2006/2007. Wheat straw was found to be the dominant source of CO, CO2, SO2, NOx, and EC emissions in the both provinces. However, for the emissions of CH4, NH3, EC, and OC, the Punjab and Sindh provinces differed markedly for the crop residue share in these pollutant emissions. Rice straw was found to be the largest contributor of CH4 (51%) and NH3 (65%) in Sindh province. When total emissions from biomass burning were considered at provincial level, wheat straw and bagasse were the major crop residues which accounted for 72 and 14% of pollutant emissions, respectively, in the Punjab province, whereas, in Sindh province, the order of crop residue contribution in total emission was as follows: wheat (59%) > bagasse (19%) > rice (14%) > cotton (7%). Emission inventory data of total pollutants per unit area under cultivation (Mg ha(-1)) revealed that Sindh province produced higher emissions per hectare for wheat straw, rice straw, and bagasse than the Punjab province.

Implications of leading crop production practices on environmental quality and human health

Globally, much weight is currently being placed on agriculture to provide food for the growing population as well as feedstock for the bioenergy industry. Unfortunately, the intensification of agricultural operations to satisfy these growing needs has been associated with a number of environmental and human health risks. A review of publications on the subject was conducted and emphasis was placed on articles focusing on agriculture, environment, and public health as well as their interactions. Supporting information was also gathered from publications of various agricultural and environmental agencies. Agricultural practices with potential negative implications on the environment and human health were identified broadly as: (a) utilization of biosolids and animal manures, (b) use of agricultural chemicals, (c) management of post-harvest residue, (d) irrigation, and (e) tillage operations. Soil, water, and air contamination by nutrients, heavy metals, pathogens, and pesticides, as well as air contamination by particulate matters, noxious gases, and pathogens were among the leading environmental impacts. Some of the human-health impacts identified included neurological and reproductive defects, cardiovascular risks, cancers and other diseases (of kidney, liver, lung, and skin), skin allergies, gastroenteritis, and methemoglobinemia. Continual awareness on the impacts of the reviewed agricultural practices on environmental quality and human health and the implementation of experimentally-backed best management practices in agricultural systems remain indispensable.

Temporal distribution of fine particulates (PM₂.₅:PM₁₀), potentially toxic metals, PAHs and Metal-bound carcinogenic risk in the population of Lucknow City, India

Ubiquitous fine particulates can readily be bound to toxic metals and polycyclic aromatic hydrocarbons and are considered to be a great threat to human health. The purpose of this study was to assess the magnitude of air pollution risks to public health by determining four crucial parameters- inhalable particulates, metals in particulates and PAHs which are associated with PM₁₀ in the air environment of Lucknow, India during 2007-09. The values of PM₁₀ and PM₂.₅ ranged between 102.3-240.5 and 28.0-196.9 μg/m³ whilst the average PM₁₀ was 1.7 times and PM was 1.5 times higher than their respective NAAQS of 100 and 60 μg/m³ respectively. The estimated relative death rate and hospital admissions for each increase in the PM₁₀ levels of 10 μg/m³ ranged from 1.5-8% and from 3.9-8.0% (as per APHEA2 1990) respectively in persons > 65 yrs. Among the locations; AQ, AQ and AQ (with diversified activities and heavy traffic) recorded higher concentrations of both the particulate fractions than the AQ (residential area with low traffic). The average concentrations of Fe, Pb, Ni, Cu, Cr, Cd in PM₁₀ were 219.4, 40.6, 35.1, 27.3, 22.2 and 16.2 ng/m³ and that in PM₂.₅ were 54.3, 33.9, 38.5, 29.4, 8.4, and 1.17 ng/m³ respectively Regression analysis revealed that correlation of metals with PM₂.₅ was stronger than PM. The ratio of metals adsorbed on surface of particles (PM₂.₅:PM₁₀) reveals that PM₂.₅ has more affinity for Ni, Cu and Pb and PM₁₀ for Cd, Fe and Cr. Health risk due to carcinogenic metals bound to respirable particulates was predicted by estimating excess cancer risk (ECR). The highest ECR value was estimated for Cr, 266.70 × 10⁻⁶, which was associated with PM10 and 100.92 × 10⁻⁶ which was associated with PM₂.₅, whereas lead has the lowest ECR value. Amongst PAHs, benzo(a)pyrene (51.96 ± 19.71 ng/m) was maximum in PM₁₀ samples. Maximum concentrations of PM₁₀, PM₂.₅, metals and PAHs were detected during winter, and the lowest was during monsoon. The higher prevalence of diseases among the population may be due to high concentration of particulates coated with toxic metals and PAHs present in air environment.

Epidemiological study on healthy subjects affected by agriculture crop-residue burning episodes and its relation with their pulmonary function tests

Impact of agriculture crop-residue burning (ACRB) was studied on pulmonary function tests (PFTs) of 50 healthy subjects (13-53 years). Human subjects with no previous history of lung disease were residents of five sampling sites. Investigations were carried out from February 2007 to January 2010 using spirometry. Simultaneously, concentration levels of suspended particulate matter (PM) and fine particulates (PM2.5 and PM10) were monitored using high volume sampler and Anderson Cascade Impactor, respectively. The PFTs show a significant (p < 0.05) decrease, while PM shows momentous increase during exhaustive burning of wheat and rice crop residues. Effect of ACRB on the peak expiratory flow rate (PEF) is more than that on force expiratory flow (FEF25-75%). The PEF and FEF25-75% recovered to some extent on completion of burning period, while PFTs like force vital capacity and force expiratory volume did not show a significant improvement. Due to greater concentration of fine particulates during rice crop-residue burning (CRB) than wheat CRB, there was a greater effect on pulmonary functions. The ACRB, in general, poses more effect on the lower and upper age groups in comparison to the middle age group subjects. All the analyses are well supported with large significant levels (p < 0.05) obtained by using the paired t-test.

Indoor fuel exposure and the lung in both developing and developed countries: an update

Almost 3 billion people worldwide burn solid fuels indoors. Despite the large population at risk worldwide, the effect of exposure to indoor solid fuel smoke has not been adequately studied. Indoor air pollution from solid fuel use is strongly associated with chronic obstructive pulmonary disease, acute respiratory tract infections, and lung cancer, and weakly associated with asthma, tuberculosis, and interstitial lung disease. Tobacco use further potentiates the development of respiratory disease among subjects exposed to solid fuel smoke. There is a need to perform additional interventional studies in this field.

Effects of exposure to rice-crop residue burning smoke on pulmonary functions and oxygen saturation level of human beings in Patiala (India)

Pulmonary Function Tests (PFTs) like Force Vital Capacity (FVC), Force Expiratory Volume in one second (FEV₁), Peak Expiratory Flow (PEF) and Force Expiratory Flow between 25 and 75% of FVC (FEF(25-75%)) and Oxygen Saturation (SpO₂) level of 50 healthy inhabitants with respect to rice crop residue burning were investigated for three rice cultivation periods from 2007 to 2009. The subjects were residents of five sampling sites selected in Patiala city. Concentration of Suspended Particulate Matter (SPM), Sulfur dioxide (SO₂), Nitrogen dioxide (NO₂) and Particulate Matter (PM) of size less than 10 and 2.5 μm (PM₁₀ and PM₂.₅) were measured by using High Volume Sampler (HVS) and Cascade Anderson Impactor. Results show that rice crop residue burning increases the pollution level in the ambient air, and PFTs undergo a significant decrease in their respective values. No significant change was seen in SpO₂ level during rice crop residue burning. In 2008, an increase of 10 μg m⁻³ in PM₂.₅, PM₁₀, SPM and NO₂ was associated significantly with decrease in FVC in percentages predicted -1.541, -1.002, -1.178, -0.232%, respectively. The decrease in air quality due to open rice crop residue burning has sub acute effect on pulmonary functions of healthy subjects and that SO₂ and NO₂ have less adverse effects on pulmonary functions than with different size Particulate Matter.