Role Of Indoor Air Pollution Research Articles

Association of anaemia with indoor air pollution among older Indian adult population: multilevel modelling analysis of nationally representative cross-sectional study

IntroductionAnaemia is a disease of public health importance with multi-causal pathways. Previous literature suggests the role of indoor air pollution (IAP) on haemoglobin levels, but this has been studied less due to logistic constraints. A high proportion of the population in developing countries, including India, still depends on unclean fuel, which exacerbates IAP. The objective was to study the association between anaemia and IAP among the older Indian adult population (≥ 45 years) as per gender.MethodsOur study analysed the nationally representative dataset of the Longitudinal Ageing Study in India (LASI 2017–18, Wave-1). We have documented the association of anaemia (outcome variable) with IAP (explanatory variable). To reduce the confounding effects of demographic and socioeconomic; health related and behavioural covariates; propensity score matching (PSM) was conducted. Nested multilevel regression modelling was conducted. States and union territories were categorised cross tabulated as low, middle and high as per anaemia and IAP exposure. P value < 0.05 was considered statistically significant. SATA version 17 was used for analysis.ResultsMore than half (52.52%) of the participants were exposed to IAP (male (53.55%) > female (51.63%)). The odds of having anaemia was significantly 1.19 times higher (AOR 1.19 (1.09–1.31)) among participants using unclean/ solid fuel. The adjusted odds were significantly higher among participants exposed to pollution-generating sources (AOR 1.30; 1.18–1.43), and household indoor smoking (AOR 1.17 (1.07–1.29). The odds of having anaemia were significantly higher (AOR 1.26; 1.15–1.38) among participants exposed to IAP, which was higher in males (AOR 1.36; 1.15–1.61) than females (AOR 1.21; 1.08–1.35). Empowered Action Group (EAG) states like Uttar Pradesh, Chhattisgarh, Madhya Pradesh, Bihar had both high anaemia and IAP exposure.ConclusionThis study established the positive association of anaemia with indoor air pollution among older Indian adults through a nationally representative large dataset. The association was higher among men. Further research is recommended to understand detailed causation and to establish temporality. It is a high time to implement positive intervention nationally to decrease solid/ unclean fuel usage, vulnerable ventilation, indoor smoking, IAP and health hazards associated with these with more focused actions towards EAG states.

COPD deaths attributable to ozone in 2019 and future projections using the WHO AQG 2021 in urban China

Chronic obstructive pulmonary disease (COPD) is an epidemic in China. Ozone is a possible risk factor of COPD, with ozone concentrations increasing in China, despite air pollution mitigation measures that reduced particulate matter. The WHO Air Quality Guidelines (AQG) recommendations in 2021 are a turning point that formally recognizes the crucial role of indoor air pollution. We aimed to investigate the premature COPD deaths attributable to ozone in 2019, taking the WHO AQG 2021 level into account to determine the gap to bridge ozone control in China. First, we assessed ozone exposures initiated from indoor and outdoor sources by gender and age groups in 344 cities under four scenarios: 2019 as a baseline, and outdoor ozone at WHO AQG 2021 level in 2019, 2030, and 2050, respectively. Subsequently, we estimated COPD deaths attributable to ozone. The results show that the COPD deaths attributable to ozone are 77,737 in 2019, and 527, 872, 1355 if the outdoor ozone concentration is reduced to the WHO AQG 2021 level in 2019 (counterfactual scenario), 2030, and 2050, respectively in urban China. The indoor ozone sources only contribute to less than 5% of COPD deaths. A gap of 68.5 μg/m3 for the highest seasonal ozone concentration should be bridged to meet the WHO AQG 2021 and avoid over 76 thousand (98%) COPD deaths in 2019 in urban China.

Early life exposure to indoor air pollutants and the risk of neurodevelopmental delays: The Japan Environment and Children’s Study

Air pollution has been associated with childhood neurodevelopment. However, the role of indoor air pollution, especially volatile organic compounds (VOCs), on childhood neurodevelopment has been poorly explored to date. We investigated the association between indoor air pollutants and childhood neurodevelopment in 5,017 randomly selected children from the Japan Environment and Children’s Study. When the participants reached 1.5 and 3 years of age, they were followed up with home visits and neurodevelopmental tests using the Ages and Stages Questionnaire (ASQ). At both ages, we collected indoor air samples for 1 week and measured 13 indoor air pollutants: particulate matter with an aerodynamic diameter of ≤2.5 μm, ozone, nitrogen dioxide, sulfur dioxide, and nine VOCs. The associations between air pollutants and ASQ scores were estimated using linear mixed effects models and weighted quantile sum regressions (WQS) at each age separately. Stratified analysis by sex was conducted. Exposure to m,p-xylene at the age of 3 was associated with lower communication, fine motor, and overall ASQ scores (coefficients: −0.18 [99% confidence intervals (CI): −0.35, −0.02], −0.23 [99 %CI: −0.43, −0.03], and − 0.72 [99 %CI: −1.41, −0.04] per 1 µg/m3 increase, respectively). Exposure to o-xylene at the age of 3 was associated with lower communication, gross motor, fine motor, and overall ASQ scores (coefficients: −0.48 [99 %CI: −0.90, −0.07], −0.45 [99 %CI: −0.78, −0.13], −0.65 [99 %CI: −1.14, −0.16], and −2.15 [99 %CI: −3.83, −0.47] per 1 µg/m3 increase, respectively). The WQS index was associated with lower gross motor ASQ scores at the age of 3 (coefficient: −0.27 [95 %CI: −0.51, −0.03] for one-unit WQS index increases), which was attributed to benzene (33.96%), toluene (26.02%), o-xylene (13.62%), and ethylbenzene (9.83%). Stratified analysis showed similar results. Although further investigations are required, our results suggest an association of neurodevelopmental delays with indoor low-level exposure to m,p-xylene and o-xylene in early life.

The effects of indoor air pollution from solid fuel use on cognitive function among middle-aged and older population in China

ObjectivesGrowing evidence has linked outdoor air pollution exposure with higher risk of cognitive impairments. However, the role of indoor air pollution in cognitive decline is not well elaborated. By using nationally representative longitudinal data, this study aimed to explore the effects of indoor air pollution from solid fuel use on cognitive function among middle-aged and older individuals in China. MethodsData were obtained from 2011 to 2015 waves of CHARLS (China Health and Retirement Longitudinal Study). Scores from the Telephone Interview of Cognitive Status and figure drawing/word recall tests were used to measure cognitive function in 39,482 individuals. Exposure to indoor air pollution was measured as use of solid fuel for cooking. Solid fuel was defined as coal, biomass charcoal, wood, and straw; clean fuel was defined as liquefied gas, natural gas, and electricity. Linear mixed effect models were applied to examine the effect of indoor air pollution from solid fuel use on cognitive function. ResultsParticipants had an average global cognitive function of 9.67 (SD = 4.13). Solid fuel users made up 49.71% of participants, but this proportion was much greater among those living in rural areas (64.22%). Compared with clean fuel users, solid fuel users had worse cognitive function. On average, solid fuel users had a 0.81 (95%CI: −0.89, −0.73) lower global cognition score, 0.63 (95%CI: −0.69, −0.57) lower mental health score, and 0.16 (95%CI: −0.22, −0.14) lower episodic memory score. These effects were stronger among participants who are female, aged 65 years old and above, have education level of primary school and below, or have cardiovascular diseases. ConclusionsThese results provide evidence for the role of indoor air pollution in neurobehavioral disorders in China. Promotion of practices like expanded use of clean fuel and improved stoves in households may be crucial to significantly reduce indoor air pollution and protect mental health.

An observational study of the role of indoor air pollution in pets with naturally acquired bronchial/lung disease.

BackgroundIndoor air pollution (IAP) is an emerging issue for both human and veterinary patients under the concept of ‘One Health’. The association between IAP and respiratory disease in companion animals has been reported.ObjectivesThe present study investigated the relationship between quantifiable indoor air quality and clinical characteristics of naturally acquired bronchial/lung disease in pet dogs and cats.MethodsA total of 36 clinical cases (20 dogs and 16 cats) with naturally acquired bronchial/lung disease were prospectively recruited. Lower airway samples were collected and analysed, and clinical signs and the information from pulmonary function testing were examined. Indoor air quality was estimated by the average concentration of particles measuring ≤2.5 μm (PM2.5, μg/m3) and volatile organic compounds (VOC, ppm) in the animals’ domestic microenvironments.ResultsExposure to IAP was not found to be correlated with the severity of clinical signs, pulmonary function changes or bronchoalveolar lavage fluid cytology in cats with bronchial/lung disease. However, a hypercellular response in canine lower airways was found to be associated with poor indoor air quality, including unacceptable indoor PM2.5 levels (>35 μg/m3) or increases in VOC concentration (>1 ppm) in places most commonly frequented by the dogs in the home.ConclusionsPoor indoor air quality may exacerbate airway disease in pets and should not be ignored in modern society.

The impact of indoor air pollution on asthma

Asthma is a common, chronic respiratory disease which is a serious issue for healthcare worldwide. When treating asthma, the main therapeutic goals are to achieve good control of symptoms and to prevent exacerbation. The interaction between genetic predis position and environmental triggers contributes to the pathophysiology of asthma. In this regard, there is growing public aware ness of the risk associated with poor indoor air quality. Because people spend considerable amounts of time every day indoors, it is important to identify and control risk factors in the indoor environment impacting individuals susceptible to asthma for successful treatment and prevention. Along with particulate matter, ozone, nitrogen dioxide, sulfur dioxide, carbon monoxide, volatile organic compounds, and second-hand smoke are the most common types of air pollutants encountered indoors. This review highlights epi demiological and experimental data on the role of indoor air pollution in the development and aggravation of asthma. Despite some studies showing significant associations between exposure to indoor air pollution and asthma morbidity, conflicting conclu sions are drawn in the literature because of limitations in study design, variation in the methods for assessing exposure, possible confounding factors, and other issues. This review will improve our understanding and facilitate the establishment of a better strat egy for asthma management and prevention. (Allergy Asthma Respir Dis 2017;5:312-319)

The role of indoor air pollution and other factors in the incidence of pneumonia in under-five children

Background The World Health Organization has asked for a spe-cial attention to the relation between pneumonia and indoor airpollution, i.e., household biomass fuel smoke, cigarette smoke,and mosquito coil smoke, especially in developing countries.Objective To analyze the role of indoor air pollution and otherfactors as risk factors for pneumonia in under-five-year children.Methods This case-control study was carried out from August un-til December 2000 at Public Health Centers in Banjarnegara,Kebumen, Jepara, and Pekalongan districts. All children qualify-ing pneumonia classification as recommended by WHO in IMCI(Integrated Management of Childhood Illness) were defined ascases and without pneumonia as controls. Severe pneumonia andno pneumonia (as classified in IMCI) were excluded. Statisticalanalysis was done using bivariate and logistic regression.Results There were three hundreds and five children with pneu-monia and 289 children without pneumonia. By bivariate analysis,biomass fuel smoke (OR=3.25; 95%CI 1.50;7.07) and cigarettesmoke exposure from other family members (OR=1.63; 95%CI1.11;2.38) were risk factors for pneumonia, while mosquito coilsmoke (OR=1.13; 95%CI 0.79;1.69) was not. History of wheezing(OR=2.60; 95%CI 2.7;8.55), malnutrition (OR=2.60; 95%CI1.33;5.07), and male sex (OR=1.47; 95%CI 1.06;2.04) were otherrisk factors.Conclusions Household biomass fuel smoke and cigarette smokewere risk factors for pneumonia. Other variables as risk factorswere history of wheezing, male sex, and malnutrition

Indoor air pollution aggravates symptoms of atopic dermatitis in children.

Most of researches on the impact of indoor air pollutants on atopic dermatitis (AD) have been based upon animal models, in vitro experiments and case-control studies. However, human data to elucidate the role of indoor air pollution on worsening symptoms of pre-existing AD from a longitudinal study are scarce. The objective of this prospective study was to evaluate the effect of indoor air pollution on AD symptoms in children. We surveyed 30 children with AD in a day-care centre, which moved to a new building during the study. These children stayed there for 8 hours a day Monday through Friday, and their daily symptom scores were recorded. Indoor and outdoor air pollutant levels were continuously measured 24 hours a day for 12 months (Period 1 to 4). Data were analyzed using a generalized linear mixed model. Compared to the period before moving (Period 1), concentrations of indoor air pollutants mostly increased after moving (Period 2) and decreased by natural ventilation and bake-out (Periods 3 and 4). The rate of positive AD symptom increased from 32.8% (Period 1) up to 43.8% (Period 2) and 50.5% (Period 3), then decreased to 35.4% in Period 4 (P < 0.0001). When the delayed effects of indoor air pollutants on AD symptoms 2 days later were evaluated, AD symptoms significantly increased by 12.7% (95% CI: -0.01 to 27.1) as toluene levels increased by 1 ppb (P = 0.05). In conclusion, indoor air pollutants increase the risk of AD aggravation in children and toluene in the indoor environment might act as an aggravating factor.

An overview of indoor air quality and its impact on respiratory health among Malaysian school-aged children.

The indoor environment is a major source of human exposure to pollutants. Some pollutants can have concentrations that are several times higher indoors than outdoors. Prolonged exposure may lead to adverse biologic effects, even at low concentrations. Several studies done in Malaysia had underlined the role of indoor air pollution in affecting respiratory health, especially for school-aged children. A critical review was conducted on the quantitative literature linking indoor air pollution with respiratory illnesses among school-aged children. This paper reviews evidence of the association between indoor air quality (IAQ) and its implications on respiratory health among Malaysian school-aged children. This review summarizes six relevant studies conducted in Malaysia for the past 10 years. Previous epidemiologic studies relevant to indoor air pollutants and their implications on school-aged children's respiratory health were obtained from electronic database and included as a reference in this review. The existing reviewed data emphasize the impact of IAQ parameters, namely, indoor temperature, ventilation rates, indoor concentration of carbon dioxide (CO2), carbon monoxide (CO), particulate matters (PM), volatile organic compounds (VOCs), nitrogen dioxide (NO2) and airborne microbes, on children's respiratory health. The study found that most of the Malaysian school-aged children are exposed to the inadequate environment during their times spent either in their houses or in their classrooms, which is not in compliance with the established standards. Children living in households or studying in schools in urban areas are more likely to suffer from respiratory illnesses compared with children living in homes or studying in schools in rural areas.

Domestic airborne pollutants and asthma and respiratory symptoms in middle age

The role of indoor air pollution as a risk factor for asthma and respiratory symptoms in middle age is unclear. We investigated associations between indoor air pollution sources and (i) asthma phenotypes and (ii) asthma-related respiratory symptoms in middle-aged adults. Subjects (n = 5729) who participated in the 2004 survey of the Tasmanian Longitudinal Health Study completed respiratory and home environment questionnaires. Associations between indoor air pollution sources, and asthma phenotypes and asthma-related respiratory symptoms were estimated. Recent mould in the home was associated with current asthma (odds ratio (OR) 1.26; 95% confidence interval 1.06-1.50), wheeze (OR 1.34; 1.17-1.54) and nocturnal chest tightness (OR 1.30; 1.12-1.51). Stratified by atopy and gender, recent mould was associated with current non-atopic asthma only in males (OR 3.73; 1.29-10.80). More rooms affected by mould were associated with significant trends for current asthma, wheeze and nocturnal chest tightness. Home environmental tobacco smoke was associated with doctor-diagnosed asthma (OR 1.25; 1.02-1.53), wheeze (OR 1.69; 1.41-2.03), nocturnal chest tightness (OR 1.54; 1.26-1.88), with current asthma only in non-smokers (OR 2.09; 95%: 1.30-3.35) and with current asthma only in males (OR 1.74; 95%: 1.25-2.42). Among heating appliances, reverse cycle air conditioning was negatively associated with doctor-diagnosed asthma (OR 0.84; 0.70-1.00). Neither electric nor gas stove use was associated with either asthma phenotype or with asthma-related respiratory symptoms. In middle age, reducing home exposure to mould and environmental tobacco smoke might reduce asthma and asthma-related respiratory symptoms.

Indoor air pollution from solid fuels and risk of upper aerodigestive tract cancers in Central and Eastern Europe

BackgroundIndoor air pollution from solid fuels is a potentially important risk factor for cancer, yet data on cancers from organs other than the lung are scarce. We investigated if indoor air pollution from coal and wood are risk factors for additional cancers, particularly that of the upper aerodigestive tract (oral cavity, larynx, pharynx and esophagus) in the high-risk areas of Central and Eastern Europe. MethodsWe used data from multi-center hospital-based case-control study of 1065 histologically confirmed upper aerodigestive tract cancer cases and 1346 controls. Standardized questionnaires were used to collect information on residential fuel use for cooking and heating. Using unconditional logistic regression, we calculated odds ratios (ORs) and 95% confidence intervals (95% CIs) for upper aerodigestive tract cancer risk after adjusting for potential confounders. ResultsLifelong wood use was associated with pharyngeal and esophageal (OR 4.05, 95% CI: 1.30–12.68 and OR 2.71, 95% CI: 1.21–6.10, respectively). We observed an exposure–response relationship between duration of wood use and risk of pharyngeal cancer among those who had never used coal (Ptrend=0.04), ruling out the possibility of residual confounding by coal. Similarly, we observed an increased risk of laryngeal cancers and head & neck cancers among those who always used coal, with a noted exposure–response relationship (Ptrend<0.01). ConclusionsOur results suggest a possible role of indoor air pollution from solid fuel use in head and neck carcinogenesis in the high risk area of Central and Eastern Europe.

The effect of housing characteristics and occupant activities on the respiratory health of women and children in Lao PDR

The paper presents the results of a study conducted into the relationship between dwelling characteristics and occupant activities with the respiratory health of resident women and children in Lao People's Democratic Republic (PDR). Lao is one of the least developed countries in south-east Asia with poor life expectancies and mortality rates. The study, commissioned by the World Health Organisation, included questionnaires delivered to residents of 356 dwellings in nine Districts in Lao PDR over a five month period (December 2005–April 2006), with the aim of identifying the association between respiratory health and indoor air pollution, in particular exposures related to indoor biomass burning. Adjusted odds ratios were calculated for each health outcome separately using binary logistic regression. After adjusting for age, a wide range of symptoms of respiratory illness in women and children aged 1–4years were positively associated with a range of indoor exposures related to indoor cooking, including exposure to a fire and location of the cooking place. Among women, “dust always inside the house” and smoking were also identified as strong risk factors for respiratory illness. Other strong risk factors for children, after adjusting for age and gender, included dust and drying clothes inside. This analysis confirms the role of indoor air pollution in the burden of disease among women and children in Lao PDR.

Association between indoor air pollution measurements and respiratory health in women and children in Lao PDR

This article presents the results of a study on the association between measured air pollutants and the respiratory health of resident women and children in Lao PDR, one of the least developed countries in Southeast Asia. The study, commissioned by the World Health Organisation, included PM(10), CO and NO(2) measurements made inside 181 dwellings in nine districts within two provinces in Lao PDR over a 5-month period (12/05-04/06), and respiratory health information (via questionnaires and peak expiratory flow rate (PEFR) measurements) for all residents in the same dwellings. Adjusted odds ratios were calculated separately for each health outcome using binary logistic regression. There was a strong and consistent positive association between NO(2) and CO for almost all questionnaire-based health outcomes for both women and children. Women in dwellings with higher measured NO(2) had more than triple of the odds of almost all of the health outcomes, and higher concentrations of NO(2) and CO were significantly associated with lower PEFR. This study supports a growing literature confirming the role of indoor air pollution in the burden of respiratory disease in developing countries. The results will directly support changes in health and housing policy in Lao PDR. This is the first study that investigated indoor air quality and its impact within residential dwellings in Lao PDR, which is one of the poorest and least developed countries in south-east Asia, with a life-expectancy of 56 years in 2008. While there have been other studies published on indoor air quality in other developing countries, the situation in Laos is different because the majority of houses in Laos used wood stoves, and therefore, emissions from wood burning are the dominant sources of indoor air pollution. In other countries, and studies, while emission from wood burning was investigated, wood was rarely the main or the only fuel used, as the houses used in addition (or solely) dung, kerosene or coal. The study quantified, for the first time, concentrations in houses two provinces in Laos PDR and shed light on the impact of human activities and urban design on pollutant concentrations and respiratory health. This study contributes to the accumulation of evidence to provide more reliable estimates of risk and a more informed basis for decision-making by concerned governments and communities.

Modulation of neurological related allergic reaction in mice exposed to low-level toluene

The contributing role of indoor air pollution to the development of allergic disease has become increasingly evident in public health problems. It has been reported that extensive communication exists between neurons and immune cells, and neurotrophins are molecules potentially responsible for regulating and controlling this neuroimmune crosstalk. The adverse effects of volatile organic compounds which are main indoor pollutants on induction or augmentation of neuroimmune interaction have not been fully characterized yet. To investigate the effects of low-level toluene inhalation on the airway inflammatory responses, male C3H mice were exposed to filtered air (control), 9 ppm, and 90 ppm toluene for 30 min by nose-only inhalation on Days 0, 1, 2, 7, 14, 21, and 28. Some groups of mice were injected with ovalbumin intraperitoneally before starting exposure schedule and these mice were then challenged with aerosolized ovalbumin as booster dose. For analysis of airway inflammation, bronchoalveolar lavage (BAL) fluid were collected to determine inflammatory cell influx and lung tissue and blood samples were collected to determine cytokine and neurotrophin mRNA and protein expressions and plasma antibody titers using real-time RT-PCR and ELISA methods respectively. Exposure of the ovalbumin-immunized mice to low-level toluene resulted in (1) increased inflammatory cells infiltration in BAL fluid; (2) increased IL-5 mRNA, decreased nerve growth factor receptor tropomyosin-related kinase A and brain-derived neurotrophic factor mRNAs in lung; and (3) increased IgE and IgG 1 antibodies and nerve growth factor content in the plasma. These findings suggest that low-level toluene exposure aggravates the airway inflammatory responses in ovalbumin-immunized mice by modulating neuroimmune crosstalk.