Jenna Ladd | February 14, 2017
University of Iowa facilities management received notice on February 1 that its drinking water system contains levels of Total Trihalomethanes (TTHM) that exceed the federal drinking water standard.
In an email sent out to University faculty, staff and students on February 9, it was reported that the drinking water tested on average between 0.081 and 0.110 mg/L over the last year. The U.S. Environmental Protection Agency’s maximum contaminant level (MCL) for TTHM is 0.08 mg/L.
TTHM is a group of four chemicals: chloroform, bromodichloromethane, dibromochloromethane and bromoform. TTHM form when chlorine reacts with natural organic matter like leaves, algae and river weeds in drinking water. In its statement, the University said that more chlorination was necessary this year because higher than usual temperatures led to more organic waste in waterways.
The notice read, “You do not need to use an alternative (e.g., bottled) water supply. Disease prevention specialists with University of Iowa Hospitals and Clinics say special precautions are not necessary.”
Chloroform and dibromochloromethane are Class B carcinogens, meaning they have been shown to cause cancer in laboratory animals. TTHM has also been linked to heart, lung, kidney, liver, and central nervous system damage, according to a report by the University of West Virginia.
University officials cautioned, “However, some people who drink water-containing trihalomethanes in excess of the MCL over many years may experience problems with their liver, kidneys, or central nervous system, and may have an increased risk of getting cancer.”
A study by the California Department of Health suggests that even short-term exposure to high TTHM levels in drinking water can have serious consequences for pregnant women. Scientists monitored 5,144 women during their first trimester of pregnancy. Participants who drank five or more glasses of cold home tap water containing 0.075 mg/L or more of TTHM had a miscarriage rate of 15.9 percent. Women that drank less than five glasses per day or who had home tap water with less than 0.075 mg/L TTHM had a miscarriage rate of 9.5 percent.
A reverse osmosis filtration system for the University of Iowa drinking water supply is currently in its design phase. Facilities management expects to have the new system up and running within the next 18 months. Officials say it will help address Iowa’s nitrate problem and filter out naturally occurring organic matter, resulting in fewer TTHM.