A new study finds that more than half of adults surveyed worldwide expect to experience serious harm from the water they consume in the next two years. The study, led by global health experts at Northwestern University and the University of North Carolina at Chapel Hill, set out to understand public perceptions about the safety of drinking water.
Because perceptions shape attitudes and behaviors, distrust in water quality has a negative impact on people’s health, nutrition, and psychological and economic well-being, even when water meets safety standards.
“If we think our water is unsafe, we will avoid using it,” said Sera Young, a professor of anthropology and global health at Northwestern and senior author of the new study.
“When we distrust tap water, we buy bottled water, which is extremely expensive and bad for the environment; we drink soda or other sugary drinks, which are bad for our teeth and waistline; and we consume highly processed prepared foods or go to restaurants to avoid cooking at home, which is less healthy and more expensive,” Young said. “People exposed to unsafe water also experience greater psychological stress and are at higher risk for depression.”
Young is the Morton O. Schapiro Professor at the Institute for Policy Research, an associate professor at the Paula M. Trienens Institute for Sustainability and Energy, and co-director of the Making Water Insecurity Visible Working Group at the Buffett Institute for Global Affairs.
Using nationally representative data from 148,585 adults in 141 countries from the Lloyd’s Register Foundation Global Risk Survey 2019, the authors found a high prevalence of anticipated harm from water supplies, with the highest in Zambia, the lowest in Singapore, and an overall mean of 52.3%.
They also identified key characteristics of those who thought the water they drank would cause harm. Women, city dwellers, people with higher levels of education, and those who had difficulty accessing their current income were more likely to anticipate that the water they drank would cause harm.
The researchers found that, surprisingly, higher scores on the corruption perception index were the strongest predictor of anticipated harm caused by drinking water, more so than factors such as infrastructure and gross domestic product.
Moreover, even in countries with consistent access to basic drinking water services, doubts about the safety of water were widespread. This includes the United States, where 39% of respondents expect serious harm from drinking water in the near term.
“Our research highlights that it is imperative to both provide safe drinking water and ensure people have confidence in their water source,” said Joshua Miller, a doctoral student at the UNC Gillings School of Global Public Health and first author of the study.
Researchers say it is difficult for consumers to judge the risks and safety of their water supply because many contaminants are invisible, odorless and tasteless. Without adequate information, many are forced to assess the safety of their water based on past experiences, media reports and personal values and beliefs.
“It’s also possible that people correctly judge the safety of their water,” Young said. “The good people of Flint didn’t trust their water, and they were right.”
The co-authors suggest actions that officials can take to improve public confidence around drinking water, including efforts to make testing more readily available, translate test results, replace lead pipes and provide home water filters when contaminants are detected, as well as provide better access to safe drinking water.
“This is the kind of work that can catalyze greater attention and political will to prioritize these services in national development plans and strategies, and bring us closer to achieving universal access to safe drinking water,” said Aaron Salzberg, director of the Water Institute at UNC’s Gillings School of Global Public Health.
Salzberg previously served as Special Coordinator for Water Resources at the U.S. Department of State, where he was responsible for managing the development and implementation of U.S. foreign policy on drinking water and sanitation, water resources management, and transboundary water issues.