[Indoor air pollution by fine particulate matter in the homes of newborns]

Air pollution by particulate matter (PM) is a major public health problem. In Chile, the study has focused on outdoor air and PM₁₀, rather than indoor air and PM_2.5. Because newborns and infants spend most of their time at home, it is necessary to evaluate the exposure to indoor air pollution in this susceptible population.

To determine concentration of PM_2.5 in the homes of newborns and identify the emission sources of the pollutants.

The PM_2.5 concentration ([PM_2.5]) was collected over a 24hour period in 207 households. Baseline sociodemographic information and environmental factors (heating, ventilation, smoking and house cleaning), were collected.

The median [PM_2.5] was 107.5μg/m³. Family history of asthma was associated with lower [PM_2.5] (P=.0495). Homes without heating showed a lower median [PM_2.5], 58.6μg/m³, while those using firewood, kerosene, and electricity ranged between 112.5 and 114.9, and coal users' homes reached 162.9μg/m³. Wood using homes had significant differences (P=.0164) in median [PM_2.5] whether the stove had complete combustion (98.2μg/m³) vs. incomplete (112.6μg/m³), or a salamander stove (140.6μg/m³). Cigarette smoking was reported in 8.7% of the households, but was not associated with the [PM_2.5]. Ventilation was associated with a higher median [PM_2.5] (120.6 vs. 99.1μg/m³, P=.0039).

We found homes with high [PM_2.5]. Residential wood consumption was almost universal, and it is associated with the [PM_2.5]. Natural ventilation increased MP_2.5, probably due to infiltration from outside.