Drought Impacts on Children’s Respiratory Health in the Brazilian Amazon

by Allison Hu

Drought conditions in Amazonia are associated with increased fire incidence, enhancing aerosol emissions with degradation in air quality. On average, the Brazilian Amazon experiences extreme flood or drought once every ten years (Smith et al. 2014). However, in 2005 and 2010, only a five-year period, two mega droughts have occurred in the Amazon. Although the 2005 drought was the first in 100 years, the second drought occurred only five years later in 2010. Environmental impacts of drought include tree mortality from water deficits and social impacts include lack of food, lack of medical supplies, isolation of communities, and even health problems. Health issues arise because during droughts, wind erosion in deforested areas causes soil particles and microbes to be blow into the air, creating and exacerbating respiratory problems and triggering allergies. Furthermore, droughts have a positive correlation with fire incidences – in Amazonia, droughts can lead to over 30% increase in fire occurrence. This too leads to more hazardous health issues as smoke from fires tends to carry fine Particulate Matter particles (PM2.5), that when inhaled, may reach deep into the lungs, causing irritation of the throat, lungs, and eyes. The primary location for fires within the Amazon is centered around the southern and eastern periphery where 85% of fires occur, emitting as much as 300-600 mg/m3 of PM10 per 24 hours and up to 400 mg/ m3 of PM2.5 per 24 hours during the dry season (Smith et al.). Measurements carried out in southern Amazonia demonstrated that exposure to PM2.5 have positive associations with children’s respiratory health. This increase of 10 mg/m3 PM2.5 has shown simultaneous correlation with a 5.6% and 2.9% increase in outpatients in Rio Branco, Acre State, and Alta Floresta, Mato Grosso State, respectively. Continue reading