Abstract:
Indoor air pollution from combustion of solid fuels for cooking is one of the ten most important risk factors of global burden of disease There is compelling evidence linking indoor smoke to acute respiratory infections in children In 2012, firewood was the principal type of cooking fuel in 78% of households in Sri Lanka. Air pollution. is a multifaceted environmental toxin affecting CNS through diverse pathways This study investigated the association between indoor air pollution and prevalence of childhood respiratory tract diseases and effects of indoor air pollution on physical growth and neuro-development of preschool children.Study was conducted in Ragama MOH area from June 2011 to June 2013. Households were selected from MOH clinics covering all the PHM areas A total of 262 children were followed up for respiratory symptoms and assessment of development. Weight and height was measured at baseline and development was assessed using the Denver development tool. Exposure was defined as "high” and "low"; the "high" group comprised households using biomass fuel or kerosene as the principal cooking fuel for cooking and the "low" group comprised households using LPG and electricity as the principal fuel for cooking Air quality measurements were done in a sub sample of households for carbon monoxide (CO), particulate matter2.5(PM2 s) and carbon dioxide(CO2). Houses in high exposure group had significantly higher concentrations of CO (mean 2.770 vs 1.44) and PM2.5(mean 1.09 vs 0.30) as compared to houses in low exposure group. CO2 levels were similar in both exposure groups. The incidence of infection induced asthma (RR=l.77, 95% CI; 1.098 - 2.949) was significantly higher among children in the high exposure group as compared to children of the low exposure group after adjusting for con-founders.
Children from high exposure group had a significantly lower mean z-scores for weight for –height (p=0.047). height=for-age(p=0.004) and weight-for-age(p=0.001) as compared to children from low exposure group after adjusting for con-founders. Z scores of weight-for- age, height-for-age and weight-for- height were negatively correlated with the levels of CO (p=0.001,0.018,0.020 respectively) and PM2.5 (p<0.001,p=0.024,p=0.008 respectively). Developmental assessment showed a significant delay in language and gross motor development domains in high exposure group as compared to low exposure group (OR=2.4;95% CI-1.00-5.42 and OR=2.3;95% CI-1.11-5.17, respectively). delays in developmental domains were correlated : fine motor and language -(r=0.50;p<0.001); fine motor and gross motor -(r=0.40;p<0.001); fine motor and social develpoment-(r=0.19;p=0.005); language and gross motor -(r=0.49;p<0.001),language and social development(r=0.22;p=0.001); and gross motor and social development(r=0.18; p=0.007). CO and PM2.5 were significantly higher in households using biomass fuel for cooking. There was a 1.6 fold higher risk of lower respiratory tract infections and two times higher risk of infection induced asthma among children in high exposure group. There was higher prevalence of stunning, wasting and under-nutrition among children in high exposure group, even after controlling for con-founders. Language and gross motor development scores were less in children living in households using biomass fuel for cooking. CO and PM2.5 were correlated with language and gross motor development scores.