For many years, scientists have warned people about the effects that eating and drinking certain things can have on our health, but tap water is something that most people accepted was good for them.
However, a new study has suggested that people in certain areas may have had their vision affected by a certain chemical contained in drinking water.
In a new study led by Boston University School of Public Health (BUSPH), researchers have found that prenatal and early childhood exposure to the chemical solvent tetrachloroethylene (PCE) may be associated with long-term visual impairments, particularly in the area of colour discrimination.
Epidemiologists and biostatisticians at the facility, in conjunction with an ophthalmologist from the BU School of Medicine, found that people exposed to higher levels of PCE from gestation through to age five exhibited poorer colour-discrimination abilities than unexposed people.
In the report, published in the journal Environmental Health Perspectives, experts have recommended further investigation into the visual impairments associated with PCE exposure.
During the analysis, the research team assessed visual functioning among a group of people born between 1969 and 1983 to parents residing in eight towns in the Cape Cod region of Massachusetts.
All of them had PCE in their drinking water because of pipes outfitted with a vinyl liner that was improperly cured, with previous studies estimating that more than 600 miles of such pipes were installed in nearly 100 cities and towns in Massachusetts, mainly during the 1970s.
The experts explained that exposure to PCE from drinking water occurs by direct ingestion, dermal exposure during bathing and by inhalation during showering, bathing and other household uses.
Although the pipes no longer leak PCE, the chemical is still widely used in dry cleaning and metal degreasing solutions and is a common drinking water contaminant.
Ann Aschengrau, professor of epidemiology at BUSPH, said the new study is the first to assess the associations between prenatal and early childhood exposure to PCE and adult vision.
"The findings suggest that the effects of early life PCE-exposure on colour discrimination may be irreversible," she added.