Exposures to fine particulate matter (PM2.5) and birthweight in a rural-urban, mother-child cohort in Tamil Nadu, India.

BACKGROUND: Exposure to PM2.5 (fine particulate matter

Can currently available advanced combustion biomass cook-stoves provide health relevant exposure reductions? Results from initial assessment of select commercial models in India.

Household air pollution from use of solid fuels is a major contributor to the national burden of disease in India. Currently available models of advanced combustion biomass cook-stoves (ACS) report significantly higher efficiencies and lower emissions in the laboratory when compared to traditional cook-stoves, but relatively little is known about household level exposure reductions, achieved under routine conditions of use. We report results from initial field assessments of six commercial ACS models from the states of Tamil Nadu and Uttar Pradesh in India. We monitored 72 households (divided into six arms to each receive an ACS model) for 24-h kitchen area concentrations of PM2.5 and CO before and (1-6 months) after installation of the new stove together with detailed information on fixed and time-varying household characteristics. Detailed surveys collected information on user perceptions regarding acceptability for routine use. While the median percent reductions in 24-h PM2.5 and CO concentrations ranged from 2 to 71% and 10-66%, respectively, concentrations consistently exceeded WHO air quality guideline values across all models raising questions regarding the health relevance of such reductions. Most models were perceived to be sub-optimally designed for routine use often resulting in inappropriate and inadequate levels of use. Household concentration reductions also run the risk of being compromised by high ambient backgrounds from community level solid-fuel use and contributions from surrounding fossil fuel sources. Results indicate that achieving health relevant exposure reductions in solid-fuel using households will require integration of emissions reductions with ease of use and adoption at community scale, in cook-stove technologies. Imminent efforts are also needed to accelerate the progress towards cleaner fuels.

Exposure to respirable particulates and silica in and around the stone crushing units in central India.

Stone crushing unit workers suffer from particulate matters and respirable silica at work and in their residents nearby. The present study was undertaken to evaluate the area and personal exposure concentration of respirable particulate matters and silica in workplaces and in surrounding villages. PM(10), PM(4) and PM(2.5) were considered for unit area measurement and PM(4) and PM(2.5) were considered for personal exposure measurements. The ambient PM(10) and indoor respirable particulate sampling and analyses were carried out in two neighboring villages adjacent to a cluster of 100 stone crushing units in central India. The study was conducted in two years with varied seasons to provide baseline data on the existing particulate concentration with and without control intervention. Monitoring and analytical criteria were fulfilled according to the National Institute for Occupational safety and Health (NIOSH), USA protocol. The study reports the higher particulates and respirable silica with respect to the national and international guidelines in and around the study units. However, in nearby villages, the particulate concentrations and silica were comparatively less. An innovative dust abatement dry engineering control system was installed as a pilot work to reduce dust emission from the unit and the results afterward were found to be encouraging.