Researchers investigate the long-term health impacts of a chemical compound found in tap water.
Chemical Compounds in Tap Water
Singapore scientists are examining the potential risks associated with trace amounts of a synthetic chemical found in tap water. Known as a by-product of diphenyl-guanidine (DPG), the compound forms when chlorine, used for disinfection, interacts with rubber components in plumbing systems. While DPG is typically found in rubber products like car tires, it has been detected in water samples from taps across Singapore.
Laboratory Findings and Concerns
In laboratory tests conducted by the Nanyang Environment and Water Research Institute (Newri) at Nanyang Technological University, the DPG-chlorine by-product showed evidence of damaging human DNA. Professor Shane Snyder, Newri’s executive director, cautioned that while the concentrations detected in Singapore’s tap water are minimal, chronic exposure over a lifetime warrants further investigation.
PUB, Singapore’s national water agency, assured the public that current water treatment processes effectively remove DPG and related compounds from reservoirs. The detected by-products likely result from interactions within plumbing systems rather than contamination at the source.
Global and Local Perspectives
Although agencies such as the World Health Organization (WHO) and the United States Environmental Protection Agency (EPA) have not identified DPG or its by-products as contaminants of concern, further studies are being prioritized. The PUB emphasized that exposure from other sources, such as air and dust, might be more significant than from tap water.
Next Steps in Research
To better understand how the DPG-chlorine compound behaves in the human body, researchers are developing an “artificial stomach” model to simulate digestion and absorption. This will help determine whether the compound is metabolized or enters the bloodstream.
Despite the findings, experts agree that Singapore’s water remains safe to drink. The study, published in Environmental Science & Technology Letters, aims to encourage further research globally, as similar chemicals may exist in water systems elsewhere.
