Benefits of boiling water with dirty fuels outweigh the risk in areas with unclean resources: Study

The Hill

13-05-2025

Boiling unclean water in many regions of the world results in air pollution from burning dirty fuels, but the benefits of doing so usually outweigh the risks, a new study has found.
The boiling process, even at low effectiveness and when using sooty stoves, leads to a daily net reduction in 'disability-adjusted life years,' or the number of healthy life years lost, according to the study, published in Environmental Health Perspectives.
'In places where there is not centralized infrastructure that provides clean water, the responsibility for addressing that risk falls to individual households,' co-corresponding author Angela Harris, an associate professor of civil, construction and environmental engineering at North Carolina State University, said in a statement.
'The advice to those households is often to boil the water before using it,' Harris continued. 'But these households often have to rely on heating sources that carry risks of their own.'
While the research community has generally focused on these risks separately, Harris and her colleagues decided to explore how the two factors overlap.
To do so, they used computational models to estimate the health impacts linked to the consumption of contaminated water and exposure to emissions from cookstoves. These models, the authors explained, accounted for varying levels of water quality and of pollution from the stoves.
'For example, cookstoves that we accounted for in this work ranged from cooking over an open woodfire to using an electric stovetop,' co-corresponding author Andrew Grieshop, a professor in the same NC State department, said in a statement.
They then used their framework to pursue case studies in both Uganda and Vietnam and incorporated public health and demographic data from both nations, Grieshop explained.
The scientists calculated the total change in disability-adjusted life years from household air pollution and diarrhea from fecal contamination of drinking water.
They determined that boiling water decreased diarrheal disease by an average of 1,100 such years and 367 years per 10,000 people, for those under and over five years old in Uganda, respectively.
Similar results materialized in Vietnam, although fewer such years were avoided in children under five there — a variance that the scientists attributed to different demographics.
'Our results reflect the established science that if people only have access to highly contaminated water, then boiling that water drastically reduces risk — particularly for children,' Harris said.
Meanwhile, she stressed that if households are already using unclean stoves for food preparation, then using those same appliances for boiling water only causes minimal increases in risk of disease.
'In other words, the modeling suggests that this is a tradeoff worth taking, especially for households with young children,' Harris added.