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ORIGINAL ARTICLE
Year : 2020  |  Volume : 64  |  Issue : 4  |  Page : 362-367  

Effect of kerosene and biomass fuel as cooking medium on pulmonary function of adult nontobacco addict homemaker women residing in slums of Ahmedabad City, Gujarat


1 Scientist, Division of Air Pollution, ICMR- National Institute of Occupational Health (NIOH), Bengaluru, Karnataka, India
2 Scientist, Department of Clinical Epidemiology, ICMR-NIOH, Bengaluru, Karnataka, India
3 Scientist, Regional Occupational Health Center (Southern), Bengaluru, Karnataka, India
4 Scientist, Bio-statistics and Data Management, ICMR-NIOH, Ahmedabad, Gujarat, India
5 Technical Staff, Division of Air Pollution, ICMR-NIOH, Ahmedabad, Gujarat, India

Date of Submission11-Dec-2019
Date of Decision02-Jun-2020
Date of Acceptance21-Jul-2020
Date of Web Publication11-Dec-2020

Correspondence Address:
Ankit P Viramgami
Department of Clinical Epidemiology, ICMR-National Institute of Occupational Health, Near Metal Cross Road, Meghaninagar, Ahmedabad - 380 016, Gujarat
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ijph.IJPH_614_19

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   Abstract 


Background: Combustion of kerosene and biomass fuel in the kitchen as cooking medium is one of the major sources of indoor air pollution. Such contaminated indoor air quality adversely affects the respiratory health of exposed individuals over a period of time. Homemaker women especially residing in slum areas are always vulnerable to indoor air-pollution-related health hazards. Objectives: The objective is to assess the relationship between various socio-demographic factors and usage patterns of cooking fuel; and to determine the effect of cooking medium namely biomass, kerosene on pulmonary function parameters. Methods: A cross-sectional observational study was carried out during April 2012 – April 2016 among 531 nontobacco addicted adult primary homemaker women residing in slums of Ahmedabad city of Gujarat. Basic information-related socio-demographic parameters were collected on a pretested questionnaire. Pulmonary function test (PFT) parameters were evaluated with standard techniques. The statistical analysis was carried out with SPSS software (version 17.0). Statistical tests of significance between groups and mean along with multivariate linear regression analysis were applied. Results: Predominant cooking medium for nearly 40% of slum households were kerosene and biomass. Mean value of forced expiratory volume in the 1st s (FEV1) and FEV1/forced vital capacity (FVC) were significantly lower among Kerosene and biomass users compared to LPG users. Multivariate regression analysis with involvement of PFT parameters, cooking medium, and environmental tobacco smoke exposure (ETS) shows, deprivation of both FEV1 and FEV1/FVC were significantly related with the usage of kerosene and biomass; whereas no relation found with ETS. Conclusion: Reduction of pulmonary function parameters among the study participants were related with kerosene and biomass fuel usage in the kitchen.

Keywords: Biomass, indoor air-pollution, kerosene, pulmonary function test, women


How to cite this article:
Kashyap R, Viramgami AP, Sadhu H G, Raghavan S, Mishra SD, Thasale RR. Effect of kerosene and biomass fuel as cooking medium on pulmonary function of adult nontobacco addict homemaker women residing in slums of Ahmedabad City, Gujarat. Indian J Public Health 2020;64:362-7

How to cite this URL:
Kashyap R, Viramgami AP, Sadhu H G, Raghavan S, Mishra SD, Thasale RR. Effect of kerosene and biomass fuel as cooking medium on pulmonary function of adult nontobacco addict homemaker women residing in slums of Ahmedabad City, Gujarat. Indian J Public Health [serial online] 2020 [cited 2023 Mar 23];64:362-7. Available from: https://www.ijph.in/text.asp?2020/64/4/362/303106




   Introduction Top


India is no longer considered as a primarily agriculture dependent country because of rapid industrial growth in the last few decades. In urban areas of India, especially because of industrialization and infrastructural developments, plenty of job and employment opportunities have been provided to the country people, which have attracted rural communities to migrate from their native places to urban settlements. It is estimated that by the year 2020, half of the Indian population will live in urban areas and among them one-third will be slum dwellers.[1] With limited resources and income, basic needs of life like shelter, cooking facilities, safe drinking water, sanitation, hygiene, nutrition, health needs, etc., were compromised at great extent among slum dwellers.[2],[3]

Due to economic constraints, lack of knowledge about the health hazards of fossil fuels and easy availability of solid and liquid fuels such as wood, cow dung, charcoal, and kerosene major proportion of slum dwellers choose one of these as a cooking medium. Burning of such solid and liquid fossil fuels as cooking medium emits various hazardous pollutants such as PM10, PM2.5, SO2, NO2, ozone, polyaromatic hydrocarbons, and benzene which negatively influences indoor air quality.[4],[5] Such, compromised indoor environment can increase the risk of acute and chronic respiratory illnesses such as cough, rhinorrhea, pneumonia, tuberculosis, asthma, chronic obstructive pulmonary disease, bronchitis, and lung cancer.[6],[7],[8]

Women and children are the most vulnerable group for hazards related to indoor air pollution which have been reported by various studies carried out across India.[9],[10],[11],[12] As predominant mode of exposure to human beings for various air pollutants is through the respiratory route, hence, the symptoms and diseases are more prevalent. The prevalence of respiratory symptoms and diseases reported in India by different studies range from 2.44% to 65.2%,[13],[14],[15] chances of over or under reporting of the illnesses or diseases are there as most of them were based on self-reported perceived illness and symptoms which also influenced by recall and other related biases. To overcome these limitations, some of the studies carried out in India have incorporated pulmonary function test (PFT) as one of the study parameters and correlated various pulmonary function parameters with type of fuel usage. [14,16-19] Influence of physiological confounding factors for PFT like age, sex, ethnicity, height, weight, nutritional status along with exposure factors like environmental tobacco smoke (ETS) exposure need to be subsided while designing the study. To overcome these limitations and identify consequences of cooking medium on PFT parameters, the present study was designed exclusively among adult nontobacco user homemaker women who were residing in slums of Ahmedabad city, Gujarat, and predominantly engaged with the cooking activity of the household. The specific objectives of the study were to assess the relationship between various socio-demographic factors and usage patterns of cooking fuel and to determine the effect of cooking medium namely biomass, kerosene on pulmonary function parameters.


   Materials and Methods Top


Study design

A cross-sectional observational study was executed in urban slums of Ahmedabad city Gujarat state, India. With all components the entire study period lasted from April 2012 to April 2016 including data collection. An individual household of slum and homemaker women residing in the same were considered as study units and study population, respectively.

Sample size and sampling-selection of study subjects

Based on the results of our pilot study (perceived prevalence of any respiratory symptoms among homemaker women residing in slums as 62.5%), desired sample size (n = 508) for the present cross-sectional study was derived through OpenEpi software (design effect-2, confidence limit ± 5%, confidence level - 90%) and a further increase 10% as nonresponse and/or dropout rate. Hence, the derived sample size was n = 558.

As a part of study design to complete the desired sample size, a detailed list of urban slums from six zones of the city were availed from the Slum Development Board of Ahmedabad city. From each zone, one slum settlement was selected randomly. With the population proportionate sampling method required number of households (study units) from each selected slum was calculated. In order to increase the participation rate, the research staff with the help of local community health workers provided sensitization at community level on the usage of fossil fuel/biomass fuel, through community meetings, before beginning the study. To meet the desired number of households in each slum, from the center of slum in any one random direction door-to-door visit was carried out and households with at least one homemaker woman who complied with inclusion and exclusion criteria were enrolled for study. In cases where more than one eligible study individuals in the household, most elder women (involved in cooking) were selected.

Adult women resident of a slum, predominantly involved in household activities (including cooking) and ready to cooperate for PFT were enrolled as study individuals. Whereas, a woman with age >60 years, not involved with cooking, engaged in work/job (outside home) and current/past tobacco user (smoking, chewing, or sniffing) were excluded from the study.

Tools and technique – Measurement of variables

A pretested, standardized semi-closed questionnaire was used to document the basic socio demographic details of the household including passive tobacco exposure and type of fuel used for cooking. In situations, where the household had more than a single medium for cooking, a fuel predominantly used for cooking purpose was considered for the study. Further, participants with at least one family member of known tobacco smoking were regarded as environmental tobacco smoke (ETS) exposure, as it could be a potential source of passive tobacco smoke exposure for study participants in the Indoor Environment of the enrolled household. Modified B G Prasad socio-economic classification with upgraded Consumer Price Index was used to determine socioeconomic status of households.[20] For anthropometric details, height (cm) was measured through nonstretchable measure tape with the accuracy of 0.1 cm and weight (kg) was measured through a pre-calibrated weighing machine with the accuracy of 0.1 kg. Body mass index (BMI) was calculated and categorized as Asian population standards.[21]

All the enrolled study participants underwent PFT with following standards and criteria of the American Thoracic Society/European Respiratory Society (ERS) with the usage of sterile techniques.[22],[23] For the same, Schiller SP-10 (Pneumotach sensor based spirometer machine) was calibrated as per instrument manual and values of forced vital capacity (FVC), forced expiratory volume in the 1st s (FEV1), ratio of FEV1 and FVC (FEV1/FVC), forced expiratory flow within the middle half of the FVC (FEF 25%–75%) and peak expiratory flow rate were measured. Predicted values and percentage predicted values were converted for Indian standards.[24] Results of PFT were described as normal (FEV1/FVC =70% and percentage predictive FVC =80%), obstructive (FEV1/FVC <70% and percentage predictive FVC =80%), restrictive (FEV1/FVC =70% and percentage predictive FVC <80%) and mixed (FEV1/FVC <70% and percentage predictive FVC <80%). Participants suspected of compromised pulmonary function were provided referral services to nearby health-care centers for further evaluation and management.

Statistical analysis

Statistical tests such as Chi-square, ANOVA, and multivariate linear regression analysis were carried out among different groups and different fuel types were executed through SPSS software version 17.0 (IBM, SPSS Inc., Chicago, IL).[25]

Ethical issues

The required ethical clearance was obtained from the Institutional Human Ethics Committee of ICMR-National Institute of Occupational Health, Ahmedabad as per document reference no. NIOH/Ethics/2010/Agenda No. 7 dated March 3, 2010. As per ethical guidelines for biomedical and health research of the Indian Council of Medical Research written informed consent was also taken from each study participant before their enrolment into study.


   Results Top


A total 578 study individuals (households) were initially enrolled for the participation into the study. Later, considering noncompliance with acceptability and repeatability criteria of PFT, refusal, drop-out and incomplete information, 47 study individuals were excluded and finally data of 531 individuals were taken into consideration for further analysis.

Majority (65.2%) of women belonged to the age group of 25–34 years and as per different cooking fuel categories no significant statistical difference was observed with the age group. Education and ETS exposure status were not significantly different among the studied population with reference to fuel usage. However, it was observed that among the socio-economically deprived families, usage of kerosene and biomass was significantly higher [Table 1].
Table 1: Background characteristics of the study population with different types cooking fuel categories used in their family

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The mean values of continuous variables and physiological confounders of PFT such as height, weight and BMI were not found to have a significant difference as per fuel type. From 531 participants, abnormal PFT (obstructive or restrictive pattern) were observed among 26 study subjects (total 4.9%, obstructive 3.4%, and restrictive 1.5%). The highest proportion of abnormal PFT results were observed among kerosene users (8.4% obstructive and 1.7% restrictive pattern) followed by biomass users (2.9% obstructive pattern) which were significantly different as per different cooking mediums. Furthermore, mean values of FEV1/FVC and FEV1 were significantly lower among kerosene (FEV1/FVC 85.42, FEV1 1.984) and biomass users (FEV1/FVC 86.58, FEV1 1.887) compared to LPG users (FEV1/FVC 88.75, FEV1 2.060), whereas FVC and FEF25%-75% were not significantly different for all three fuel groups [Table 2].
Table 2: Mean values of anthropometric and pulmonary function test parameters along with status of Pulmonary Function Test according to different cooking fuel categories

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Results of multivariate linear regression analysis for different pulmonary functions showed significant negative relationship of FEV1/FVC and FEV1 among biomass (FEV1/FVC, P = 0.049, β = -0.084; FEV1, P = 0.000, β = -0.156) and kerosene users (FEV1/FVC, P = 0.000, β = -0.198; FEV1, P = 0.003, β = -0.117) while considering LPG user as reference. Along with that, FVC showed significant relationship with biomass usage (P = 0.001, β = -0.133) and FEF25%–75% showed significant relationship with kerosene usage (P = 0.006, β = -0.119). However, tobacco smoke exposure was not found to be related with any of these pulmonary functions [Table 3].
Table 3: Comparison of pulmonary function parameters among different cooking fuel categories with the usage of multivariate linear regression analysis

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   Discussion Top


As per the National Family Health Survey report NFHS-4 (2015–2016) data, 44.2% (urban 11.5% and rural 71.2%) households were using solid fuels in Gujarat.[26] As per recent survey report of 76th round NSSO survey (2019), nearly 61% households of India using LPG as household cooking medium.[27] The present study reports overall usage of kerosene and biomass were 33.5% and 6.6% among families residing in slums of Ahmedabad city and with deprivation in socioeconomic class usage of kerosene and biomass increases. Studies have documented usage of kerosene as a cooking medium in Kolkata and Pune were 60% and 22%, respectively.[5],[15] The reason for the same would be financial constraints, easy availability of fossil fuels and lack of awareness about the harmful effects of kerosene and solid fuels. With a limited decision power of women compared to adult male/other older female members of the family and superseded by relevant socioeconomic factors, it was less likely that the age and literacy status of homemaking women could influence usage of household fuel. This could be a probable explanation for kitchen fuel among dwellings was not different with age and literacy status of women.

Based on the history of respiratory illnesses, many studies have documented significant high proportion of respiratory morbidities among biomass fuel users compared to smokeless fuel users.[7],[8],[12] A study carried out in Rajasthan (Parikh et al., 2019) has reported significant association between respiratory symptoms and fuel medium with controlling effects of age and education.[8] Similar to present study, recent Indian studies Dave et al. (2017), Arora et al. (2018), Panigrahi et al. (2018), and Patel et al. (2018) have also reported high proportion of obstructive and restrictive pattern of PFT with usage of traditional fuel in comparison to smokeless fuel (LPG).[6],[17],[18],[28] In addition to that in current study with the usage of regression statistics we have neutralized influence of physiological (age, height, weight, etc.,) and ETS exposure to study influence of type fuel on PFT parameters. After adjusted for physiological factors (age, height, weight, etc.), the usage of biomass and kerosene were related with deprivation of FEV1 and FEV1/FVC both. Whereas, deprivation of FEF 25%–75% and FVC related with kerosene and biomass usage, respectively. However, the mechanism for the observed pulmonary function alteration was not described through these studies but the observed findings may be related to inflammatory mediator associated inflammation, thickening, narrowing, remodeling of airway and/or fibrotic changes of other lung tissues due to exposure of various pollutants of fossil fuels.[29],[30] Considering the fact that because of the responsibility of earning, male adult members of the household remain outside the house during the majority of the day time, which was probable reason or explanation for pulmonary functions were not found associated with passive smoking exposure (ETS) in the present study.

Authors accept that the study represents only limited geographical areas (slums) of a particular city and neither quantified the indoor pollutants nor considered quality of ventilation measures available in the kitchen. Furthermore, it has not considered past fuel type and duration of usage, other indoor environmental exposures (such as incense sticks, mosquito coil, and oil used in kitchen), influence of outdoor air quality (ambient air quality), past major respiratory illness (including preterm delivery and respiratory distress in the neonatal period) and family history of respiratory problems such as asthma which may influence pulmonary function parameters of subjects. Further, multicentric prospective study requires to overcome limitations of the present study and to establish dose response relationship between pollution exposure and health consequences.


   Conclusion Top


The current study observed a substantially high proportion of biomass/kerosene fuel usage for cooking purposes among households of urban slums. Further, biomass and kerosene users experienced compromised lung function as compared to their counterparts using the smokeless fuel (LPG). The results were controlled for the influences of passive tobacco smoking and physiological parameters. As a primordial preventive step to reduce the chronic respiratory burden, smokeless cooking fuel is being promoted by government initiatives (such as Ujjawala Yojana). However, the current results indicate the suboptimal reach of clean fuel (LPG), hence future qualitative studies are recommended to evaluate the reasons for enhancing the outreach.

Financial support and sponsorship

Indian Medical Council Research (ICMR), New Delhi, India.

Conflicts of interest

There are no conflicts of interest.



 
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    Tables

  [Table 1], [Table 2], [Table 3]


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