Effects of air pollution on respiratory parameters during the wheat-residue burning in Patiala

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.

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.

Retrospection of heatwave and heat index

The frequency and intensity of extreme events especially heat waves (HW) are growing all around the world which ultimately poses a serious threat to the health of individuals. To quantify the effects of extreme temperature, appropriate information, and the importance of HW and heat index (HI) are carefully discussed for different parts of the world. Varied definitions of the HW and HI formula proposed and used by different countries are carried out systematically continent-wise. Different studies highlighted the number of definitions of HW; however, mostly used Steadman's formulae, which was developed in the late 1970s, for the calculation of HI that uses surface air temperature and relative humidity as climatic fields. Since then, dramatic changes in climatic conditions have been observed as evident from the ERA5 datasets which need to be addressed; likewise, the definition of HW, which is modified by the researchers as per the geographic conditions. It is evident from the ERA5 data that the temperature has increased by 1-2 °C as compared to the 1980s. There is a threefold increase in the number of heatwave days over most of the continents in the last 40 years. This study will help the researcher community to understand the importance of HW and HI. Furthermore, it opens the scope to develop an equation based on the present scenario keeping in mind the basics of an index as considered by Steadman.

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.

Farming, pesticide exposure and respiratory health: a cross-sectional study in Thailand

OBJECTIVE

To assess the association of lung function and respiratory symptoms with farming, particularly pesticide use, in an agricultural province in Thailand.

METHODS

We undertook a cross-sectional survey of adults aged 40-65 in Nan province, Thailand, between May and August 2019. We randomly recruited 345 villagers and enriched the sample with 82 government employees. All participants performed post-bronchodilator spirometry and completed a questionnaire covering information on respiratory symptoms, farming activities, pesticide use and known risk factors for respiratory disease. Associations of respiratory outcomes with farming and pesticide exposures were examined by multivariable regression analysis.

RESULTS

The response rate was 94%. The prevalence of chronic airflow obstruction among villagers was 5.5%. Villagers had, on average, a lower percent predicted post-bronchodilator forced expiratory volume in one second/forced vital capacity (FEV₁/FVC) than government employees (98.3% vs 100.3%; p=0.04). There was no evidence of association of lung function with farming activities, the use of specific herbicides (glyphosate and paraquat), insecticides (organophosphates and pyrethroids) or fungicides. The exceptions were poultry farming, associated with chronic cough and an increase of FEV₁/FVC, and atrazine, for which duration (p-trend <0.01), intensity (p-trend <0.01) and cumulative hours (p-trend=0.01) of use were all associated with higher FEV₁/FVC in an exposure-response manner. Cumulative hours (-280 mL/hour), low duration (-270 mL/year) and intensity (-270 mL/hour/year) of atrazine use were associated with lower FVC.

CONCLUSIONS

Chronic airflow obstruction is uncommon among villagers of an agricultural province in Nan, Thailand. Farming and pesticide use are unlikely to be major causes of respiratory problems there.

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.

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.

Effect of outdoor particulate air pollution on FEV1 in healthy adults: a systematic review and meta-analysis

The effect of acute and long-term exposures to outdoor particulate air pollution on lung function in healthy adults is not well established. The objective of this study was to conduct a systematic literature review and meta-analysis of studies that assessed the relationship of outdoor particulate air pollution and lung function in healthy adults. Studies that contained data on outdoor air particulate matter levels (PM₁₀ or PM_2.5) and forced expiratory volume in 1 s (FEV₁) in healthy adults were eligible for inclusion. Effect estimates, in relation to long-term and acute exposures, were quantified separately using random effects models. A total of 27 effect estimates from 23 studies were included in this review. Acute exposures were typically assessed with PM_2.5, while long-term exposures were predominantly represented by PM₁₀ A 10 µg/m3 increase in short-term PM_2.5 exposure (days) was associated with a -7.02 mL (95% CI -11.75 to -2.29) change in FEV₁ A 10 µg/m³ difference in long-term PM₁₀ exposure was associated with a -8.72 mL (95% CI -15.39 to -2.07) annual change in FEV₁ and an absolute difference in FEV₁ of -71.36 mL (95% CI -134.47 to -8.24). This study provides evidence that acute and long-term exposure to outdoor particulate air pollution are associated with decreased FEV₁ in healthy adults. Residual confounding from other risk factors, such as smoking, may explain some of the effect for long-term exposures. More studies are required to determine the relationship of long-term exposure to PM_2.5 and short-term exposure to PM₁₀, which may have different biologic mechanisms.

Função pulmonar e depuração mucociliar nasal de cortadores de cana-de-açúcar brasileiros expostos à queima de biomassa

Resumo Objetivos: avaliar a função pulmonar e a depuração mucociliar nasal de cortadores de cana-de-açúcar. Métodos: foram avaliados dezesseis cortadores de cana-de-açúcar em dois períodos: durante o plantio da cana-de-açúcar, em abril/2011, e no final da safra, no período de queima e colheita manual da cana-de-açúcar, outubro/2011. A função pulmonar e a depuração mucociliar foram avaliadas por meio da espirometria e do teste de tempo de trânsito da sacarina (TTS), respectivamente. Resultados: a função pulmonar apresentou diminuição no %FEF25-75 [99,31 (23,79) até 86,36 (27,41); p = 0,001]; %VEF1 [92,19 (13,24) até 90,44 (12,76); p = 0,022] e VEF1/CVF [88,62 (5.68) até 84,90 (6.47); p = 0,004] no período da colheita em comparação ao de plantio. Também houve uma diminuição significativa no resultado do teste do TTS na colheita [3 (1) min] em comparação ao plantio [8 (3) min] (p < 0,001). Conclusão: os cortadores de cana-de-açúcar apresentaram diminuição do %FEF25-75, %VEF1, do índice VEF1/CVF, e aumento da velocidade do transporte mucociliar nasal no final do período de colheita.

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.

Burnt sugarcane harvesting: particulate matter exposure and the effects on lung function, oxidative stress, and urinary 1-hydroxypyrene

Non-mechanised sugarcane harvesting preceded by burning exposes workers and the people of neighbouring towns to high concentrations of pollutants. This study was aimed to evaluate the respiratory symptoms, lung function and oxidative stress markers in sugarcane workers and the residents of Mendonça, an agricultural town in Brazil, during the non-harvesting and harvesting periods and to assess the population and individual exposures to fine particulate matter (PM(2.5)). Sugarcane workers and healthy volunteers were evaluated with two respiratory symptom questionnaires, spirometry, urinary 1-hydroxypyrene levels, and the measurement of antioxidant enzymes and plasma malonaldehyde during the non-harvesting and harvesting periods. The environmental assessment was determined from PM(2.5) concentration. PM(2.5) level increased from 8 μg/m³ during the non-harvesting period to 23.5 μg/m³ in the town and 61 μg/m³ on the plantations during the harvesting period. Wheezing, coughing, sneezing, and breathlessness increased significantly in both groups during the harvesting period, but more markedly in workers. A decrease in lung function and antioxidant enzyme activity was observed in both populations during harvesting; this decrease was greater among the sugarcane workers. The urinary 1-hydroxypyrene levels only increased in the sugarcane workers during the harvesting period. The malonaldehyde levels were elevated in both groups, with a higher increase observed in the workers. This research demonstrates the exposure of sugarcane workers and the inhabitants of a neighbouring town to high PM(2.5) concentrations during the sugarcane harvest period. This exposure was higher among the sugarcane workers, as illustrated by both higher PM(2.5) concentrations in the sugarcane fields and higher urinary 1-hydroxypyrene levels in the volunteers in this group. The higher incidence of respiratory symptoms, greater decrease in lung function and more marked elevation of oxidative stress markers among the sugarcane workers during the harvest confirms the greater effect magnitude in this population and a dose-dependent relationship between pollution and the observed effects.

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.

Study of size and mass distribution of particulate matter due to crop residue burning with seasonal variation in rural area of Punjab, India

Emission from field burning of agricultural crop residue is a common environmental hazard observed in northern India. It has a significant potential health risk for the rural population due to respirable suspended particulate matter (RSPM). A study on eight stage size segregated mass distribution of RSPM was done for 2 wheat and 3 rice crop seasons. The study was undertaken at rural and agricultural sites of Patiala (India) where the RSPM levels remained close to the National Ambient Air quality standards (NAAQS). Fine particulate matter (PM(2.5)) contributed almost 55% to 64% of the RSPM, showing that, in general, the smaller particles dominated during the whole study period with more contribution during the rice crop as compared to that of wheat crop residue burning. Fine particulate matter content in the total RSPM increased with decrease in temperature. Concentration levels of PM(10) and PM(2.5) were higher during the winter months as compared to that in the summer months. Background concentration levels of PM(10), PM(2.5) and PM(10-2.5) were found to be around 97 ± 21, 57 ± 15 and 40 ± 6 μg m(-3), respectively. The levels increased up to 66, 78 and 71% during rice season and 51, 43 and 61% during wheat crop residue burning, respectively. Extensive statistical analysis of the data was done by using pair t-test. Overall results show that the concentration levels of different size particulate matter are greatly affected by agricultural crop residue burning but the total distribution of the particulate matter remains almost constant.

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

Variations in pulmonary function tests (PFTs) due to agriculture crop residue burning (ACRB) on children between the age group of 10 to 13 years and the young between 20 to 35 years are studied. The effects of exposure to smoke due to rice-wheat crop residue burning on pulmonary functions like Force Vital Capacity (FVC), Force Expiratory Volume in one second (FEV(1)), Peak Expiratory Flow (PEF) and Force Expiratory Flow in 25 to 75% of FVC (FEF(25-75%)) on 40 healthy subjects of rural/agricultural area of Sidhuwal village of Patiala City were investigated for a period from August 2008 to July 2009. Measurements were taken by spirometry according to the American Thoracic Society standards. High volume sampler (HVS) and Anderson Impactor were used to measure the concentration levels of SPM, PM(10) and PM(2.5) in ambient air of the Sidhuwal village. A significant increase in the concentration levels of SPM, PM(10) and PM(2.5) was observed due to which PFTs of the subjects showed a significant decrease in their values, more prominently in the case of children. PFTs of young subjects recovered up to some extent after the completion of burning period but the PFT values of children remained significantly lower (p<0.001) even after the completion of burning episodes. Small size particulate matter (PM(2.5) and PM(10)) affected the PFTs to a large extent in comparison to the large size particulate matter (SPM). The study indicates that ACRB is a serious environmental health hazard and children are more sensitive to air pollution, as ACRB poses some unrecoverable influence on their PFTs.