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Global Health Action | 2011

Air pollution from household solid fuel combustion in India: an overview of exposure and health related information to inform health research priorities

Kalpana Balakrishnan; Padmavathi Ramaswamy; Sankar Sambandam; Gurusamy Thangavel; Santu Ghosh; Priscilla Johnson; Krishnendu Mukhopadhyay; Vidhya Venugopal; Vijayalakshmi Thanasekaraan

Environmental and occupational risk factors contribute to nearly 40% of the national burden of disease in India, with air pollution in the indoor and outdoor environment ranking amongst leading risk factors. It is now recognized that the health burden from air pollution exposures that primarily occur in the rural indoors, from pollutants released during the incomplete combustion of solid fuels in households, may rival or even exceed the burden attributable to urban outdoor exposures. Few environmental epidemiological efforts have been devoted to this setting, however. We provide an overview of important available information on exposures and health effects related to household solid fuel use in India, with a view to inform health research priorities for household air pollution and facilitate being able to address air pollution within an integrated rural–urban framework in the future.


Global Health Action | 2011

Prevalence of chronic obstructive pulmonary disease in rural women of Tamilnadu: implications for refining disease burden assessments attributable to household biomass combustion

Priscilla Johnson; Kalpana Balakrishnan; Padmavathi Ramaswamy; Santu Ghosh; Muthukumar Sadhasivam; Omprakash Abirami; Bernard W. C. Sathiasekaran; Kirk R. Smith; Vijayalakshmi Thanasekaraan; Arcot S. Subhashini

Background Chronic obstructive1 1This paper was orally presented in the Annual conference International Society of Environmental Epidemiology held in Pasadena in 2008. pulmonary disease (COPD) is the 13th leading cause of burden of disease worldwide and is expected to become 5th by 2020. Biomass fuel combustion significantly contributes to COPD, although smoking is recognized as the most important risk factor. Rural women in developing countries bear the largest share of this burden resulting from chronic exposures to biomass fuel smoke. Although there is considerable strength of evidence for the association between COPD and biomass smoke exposure, limited information is available on the background prevalence of COPD in these populations. Objective This study was conducted to estimate the prevalence of COPD and its associated factors among non-smoking rural women in Tiruvallur district of Tamilnadu in Southern India. Design This cross-sectional study was conducted among 900 non-smoking women aged above 30 years, from 45 rural villages of Tiruvallur district of Tamilnadu in Southern India in the period between January and May 2007. COPD assessments were done using a combination of clinical examination and spirometry. Logistic regression analysis was performed to examine the association between COPD and use of biomass for cooking. R software was used for statistical analysis. Results The overall prevalence of COPD in this study was found to be 2.44% (95% CI: 1.43–3.45). COPD prevalence was higher in biomass fuel users than the clean fuel users 2.5 vs. 2%, (OR: 1.24; 95% CI: 0.36–6.64) and it was two times higher (3%) in women who spend >2 hours/day in the kitchen involved in cooking. Use of solid fuel was associated with higher risk for COPD, although no statistically significant results were obtained in this study. Conclusion The estimates generated in this study will contribute significantly to the growing database of available information on COPD prevalence in rural women. Moreover, with concomitant indoor air pollution measurements, it may be possible to increase the resolution of the association between biomass use and COPD prevalence and refine available attributable burden of disease estimates.


BMJ Open | 2015

Establishing integrated rural–urban cohorts to assess air pollution-related health effects in pregnant women, children and adults in Southern India: an overview of objectives, design and methods in the Tamil Nadu Air Pollution and Health Effects (TAPHE) study

Kalpana Balakrishnan; Sankar Sambandam; Padmavathi Ramaswamy; Santu Ghosh; Vettriselvi Venkatesan; Gurusamy Thangavel; Krishnendu Mukhopadhyay; Priscilla Johnson; Solomon F. D. Paul; Naveen Puttaswamy; Rupinder S Dhaliwal; Deepak Kumar Shukla; Sru-Car Team

Introduction In rapidly developing countries such as India, the ubiquity of air pollution sources in urban and rural communities often results in ambient and household exposures significantly in excess of health-based air quality guidelines. Few efforts, however, have been directed at establishing quantitative exposure–response relationships in such settings. We describe study protocols for The Tamil Nadu Air Pollution and Health Effects (TAPHE) study, which aims to examine the association between fine particulate matter (PM2.5) exposures and select maternal, child and adult health outcomes in integrated rural–urban cohorts. Methods and analyses The TAPHE study is organised into five component studies with participants drawn from a pregnant mother–child cohort and an adult cohort (n=1200 participants in each cohort). Exposures are assessed through serial measurements of 24–48 h PM2.5 area concentrations in household microenvironments together with ambient measurements and time-activity recalls, allowing exposure reconstructions. Generalised additive models will be developed to examine the association between PM2.5 exposures, maternal (birth weight), child (acute respiratory infections) and adult (chronic respiratory symptoms and lung function) health outcomes while adjusting for multiple covariates. In addition, exposure models are being developed to predict PM2.5 exposures in relation to household and community level variables as well as to explore inter-relationships between household concentrations of PM2.5 and air toxics. Finally, a bio-repository of peripheral and cord blood samples is being created to explore the role of gene–environment interactions in follow-up studies. Ethics and dissemination The study protocols have been approved by the Institutional Ethics Committee of Sri Ramachandra University, the host institution for the investigators in this study. Study results will be widely disseminated through peer-reviewed publications and scientific presentations. In addition, policy-relevant recommendations are also being planned to inform ongoing national air quality action plans concerning ambient and household air pollution.


Lung India | 2014

Effect of cigarette smoking on nasal mucociliary clearance: A comparative analysis using saccharin test

Manu Kurian Baby; Prathibha K Muthu; Priscilla Johnson; Senthil Kannan

Background: Nasal mucociliary clearance (NMC) system transports the mucus layer covering the nasal epithelium towards nasopharynx by ciliary beating at a frequency of 7-16 Hz. NMC is altered by septal deviations, upper respiratory infections, and drugs. Few studies have revealed significant depression of ciliary activity in smokers. We conducted this study to compare NMC and influence duration of smoking on NMC in adult smokers and nonsmokers using saccharin test. Materials and Methods: Our study included 30 nonsmokers and 30 smokers (21-40 years) who were not on any medications and had no history of any systemic illness. Time elapsing until the first experience of sweet taste at posterior nasopharynx, following placement of saccharin particle approximately 1 cm behind the anterior end of inferior turbinate was recorded as NMC time in minutes using standard method described by Anderson. Mean NMC of both groups were compared using Students t-test and influence of duration was analyzed by one-way Analysis of variance (ANOVA). Results: NMC was significantly prolonged in smokers (481.2 ± 29.83; P < 0.01) in comparison to nonsmokers (300.32 ± 17.42 s). A statistically significant increase in NMC was observed with an increase in duration of smoking habit (NMC in smoking <1 year = 492.25 ± 79.93 s, 1-5 years = 516.7 ± 34.01 s, >5 years = 637.5 ± 28.49 s; F statistic = 20.8968, P = 0.0000). Conclusions: NMC measurement is a simple and useful index for the assessment of effect of smoking on the ciliary activity of respiratory mucosa. Prolonged clearance observed in smokers of our study may be due to slowed ciliary beat frequency or reduction in number of cilia and changes in viscoelastic properties of mucus.


International Scholarly Research Notices | 2013

The Effect of Ageing on Nasal Mucociliary Clearance in Women: A Pilot Study

Preetha Paul; Priscilla Johnson; Padmavathi Ramaswamy; Sitalakshmi Ramadoss; Bagavad Geetha; As Subhashini

Introduction. Pneumonia is the leading infectious cause of death in the elderly. Impaired respiratory defences are one of the causes for increased susceptibility of the elderly to such infections. Nasal mucociliary clearance, the mirror image of bronchial clearance, is crucial in respiratory defence and is affected by various factors. Little is known about the effect of ageing on nasal respiratory epithelium. Aim. To evaluate the effect of ageing on nasal mucociliary clearance (NMC) in women. Materials and Methods. NMC was measured in 91 apparently healthy women of ages ranging from 20 to 80 years. The time taken to experience sweet taste at nasopharynx following the placement of saccharin pellet in the nostril was recorded as NMC time. Results and Discussion. NMC time was 10 min 36 secs in elderly women and it was significantly prolonged when compared to younger women (8 min 39 secs). The prolonged clearance may be due to altered cilia, slowed ciliary beating, or changes in the properties of mucus. Conclusion. NMC time clearly shows an increase with age signifying decreasing respiratory epithelium function. This study highlights an important cause of impaired respiratory health in older individuals and emphasises the need for preventive measures to be put in place.


Environmental Research | 2018

Exposures to fine particulate matter (PM 2.5 ) and birthweight in a rural-urban, mother-child cohort in Tamil Nadu, India

Kalpana Balakrishnan; Santu Ghosh; Gurusamy Thangavel; Sankar Sambandam; Krishnendu Mukhopadhyay; Naveen Puttaswamy; Arulselvan Sadasivam; Padmavathi Ramaswamy; Priscilla Johnson; Rajarajeswari Kuppuswamy; Durairaj Natesan; Uma Maheshwari; Amudha Natarajan; Gayathri Rajendran; Rengaraj Ramasami; Sathish Madhav; Saraswathy Manivannan; Srinivasan Nargunanadan; Srinivasan Natarajan; Sudhakar Saidam; Moumita Chakraborty; Lingeswari Balakrishnan; Vijayalakshmi Thanasekaraan

Background: Exposure to PM2.5 (fine particulate matter <less than 2.5 &mgr;m in aerodynamic diameter) related to ambient and household air pollution has been associated with low birthweight. Few of these studies, however, have been conducted in high exposure settings that are commonly encountered in low and middle income countries (LMICs). Objectives: We examined whether PM2.5 exposures during pregnancy were associated with birthweight in an integrated rural‐urban, mother‐child cohort in the state of Tamil Nadu, India. Methods: We recruited 1285 pregnant women in the first trimester of pregnancy from primary health care centers and urban health posts and followed them until birth to collect antenatal care data and birthweight. We estimated pregnancy period PM 2.5 exposures through direct serial measurements of 24‐h household PM2.5 concentrations, performed across each trimester. Mothers also completed detailed questionnaires to provide data on covariates related to household, socio‐economic, demographic and maternal health characteristics. The association between PM2.5 exposures and birth weight was assessed using linear and logistic regression models that controlled for potential confounders. Results: A 10‐&mgr;g/m3 increase in pregnancy period PM2.5 exposures was associated with a 4 g (95% CI: 1.08 g, 6.76 g) decrease in birthweight and 2% increase in prevalence of low birthweight [odds ratio(OR) = 1.02; 95%CI:1.005,1.041] after adjusting for gestational age, infant sex, maternal BMI, maternal age, history of a previous low birth weight child, birth order and season of conception. Conclusions: The study provides some of the first quantitative effects estimates for linking rural‐urban PM2.5 exposures and birthweight in India, adding important evidence for this association from high exposure settings in LMICs, that also experience dual health burdens from ambient and household air pollution. Study results also point to the need for considering maternal PM2.5 exposures alongside other risk factors for low birthweight in India HIGHLIGHTSProvides E‐R relationships between PM2.5 and birth‐weight in high exposure settings.Examines the association in a rural‐urban, mother‐child cohort in India.Estimates a 4g decrease in birth‐weight per 10‐&mgr;g/m3 increase in PM2.5 exposures.Estimates a 2% increase in low birth‐weight per 10‐&mgr;g/m3 increase in PM2.5 exposures.Maternal PM2.5 exposures may be an important risk factor for low birth‐weight in India.


Lung India | 2015

Assessment of phagocytic activity of neutrophils in chronic obstructive pulmonary disease

Lalitha Shanmugam; Sheela Ravinder; Priscilla Johnson; Ramaswamy Padmavathi; B Rajagopalan; Anupma Jyoti Kindo

Aim: To assess the phagocytic activity of neutrophils in subjects with chronic obstructive pulmonary disease (COPD). Background/Need of Study: There is a paucity of data in relation to phagocytic function in COPD. By this multidisciplinary study, a better understanding about the etiology of lung destruction among COPD patients is being sought. Materials and Methods: The study was conducted among 28 subjects with COPD and 25 controls in a private tertiary hospital in Chennai after obtaining Institutional Ethical Clearance. Known cases of COPD as proven by clinical findings and spirometry were included in the study, and subjects with any other source of infection, recent surgery, or chronic granulomatous disease were excluded. The study subjects were divided into three groups based on the severity of COPD as determined by spirometry, and healthy volunteers were taken as Group 4. After obtaining informed consent, validated respiratory health questionnaire was administered. The phagocytic function was assessed by Candida phagocytic test and Nitroblue Tetrazolium (NBT) Reduction Test. Results: Significantly impaired phagocytic function as indicated by lower phagocytic, lytic indices and decreased NBT reduction of neutrophils was seen in COPD subjects compared to normal healthy controls (P <.001). Conclusion: This study showed that there is phagocytic dysfunction in COPD subjects when compared with normal subjects. This could be due to underlying inflammation in human airway. Understanding the role of neutrophils may lead to improved understanding of the pathogenesis of COPD, which in turn may pave way for implementing modified therapeutic intervention strategies.


Journal of Applied Toxicology | 2018

Associations between household air pollution and reduced lung function in women and children in rural southern India: ASSOCIATIONS BETWEEN HOUSEHOLD AIR POLLUTION AND LUNG FUNCTION

Sameer Patel; Anna Leavey; Ajay Sheshadri; Praveen Kumar; Sandeep Kandikuppa; Jaime Tarsi; Krishnendu Mukhopadhyay; Priscilla Johnson; Kalpana Balakrishnan; Kenneth B. Schechtman; Mario Castro; Gautam Yadama; Pratim Biswas

Half of the worlds population still relies on solid fuels to fulfill its energy needs for cooking and space heating, leading to high levels of household air pollution (HAP), adversely affecting human health and the environment. A cross‐sectional cohort study was conducted to investigate any associations between: (1) HAP metrics (mass concentration of particulate matter of aerodynamic size less than 2.5 μm (PM2.5), lung‐deposited surface area (LDSA) and carbon monoxide (CO)); (2) a range of household and socio‐demographic characteristics; and (3) lung function for women and children exposed daily to biomass cookstove emissions, in rural southern India. HAP measurements were collected inside the kitchen of 96 households, and pulmonary function tests were performed for the women and child in each enrolled household. Detailed questionnaires captured household characteristics, health histories and various socio‐demographic parameters. Simple linear and logistic regression analysis was performed to examine possible associations between the HAP metrics, lung function and all household/socio‐demographic variables. Obstructive lung defects (forced vital capacity (FVC) ≥ lower limit of normal (LLN) and forced expiratory volume in 1 second (FEV1)/FVC < LLN) were found in 8% of mothers and 9% of children, and restrictive defects (FVC < LLN and FEV1/FVC ≥ LLN) were found in 17% of mothers and 15% of children. A positive association between LDSA, included for the first time in this type of epidemiological study, and lung function was observed, indicating LDSA is a superior metric compared to PM2.5 to assess effects of PM on lung function. HAP demonstrated a moderate association with subnormal lung function in children. The results emphasize the need to look beyond mass‐based PM metrics to assess fully the association between HAP and lung function.


Journal of Pharmacy and Bioallied Sciences | 2015

Anatomy research under the knife of medical ethics

W. M. S. Johnson; R Archana; Km Prathibha; Priscilla Johnson

There is increased awareness and anxiety in conducting research for publication and at the same time ignorance about getting Ethical Committee clearance at least in Anatomy Departments among Basic Medical Sciences. While people are actively presenting papers, collect data, Indian Council for Medical Research guidelines does not cover aspects pertaining to Anatomy oriented research activities. This review article is an eye opener for fraternity in the medical field, especially in anatomy.


Epidemiology | 2011

Development and Application of Spatially Disaggregated Exposure Series in Time-series Analyses of Air Pollution-related Health Effects in Chennai, India

Santu Ghosh; Priscilla Johnson; Sheela Ravinder; Moumita Chakraborty; Moti Mittal; Kalpana Balakrishnan

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Santu Ghosh

Sri Ramachandra University

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Sheela Ravinder

Sri Ramachandra University

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Sankar Sambandam

Sri Ramachandra University

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As Subhashini

Sri Ramachandra University

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