The Minnesota Health Department has admitted it failed in testing some drinking water supplies.
The department announced Thursday its Environmental Health Division’s test results were inconsistent, and in some cases inadequate. Health Commissioner Dr. Ed Ehlinger said the issues are unlikely to cause a public health threat, but they will be addressed immediately.
“While the situation as a whole would not suggest an increased risk for most communities, we want to ensure we have the highest level of reliability in our data on drinking water quality,” Ehlinger said. “This inconsistency is unacceptable and should not have happened. We’re moving swiftly to correct it.”
An internal department review caught the problem. Some water samples were not kept at the proper temperature, an issue that dates to the early 1990s.
The department regularly conducts water sampling of public drinking water systems around the state.
“Even though that evidence would suggest the risk to communities is low, recent events like the case in Flint, Mich., show the special expectations that exist around drinking water safety,” the Health Department’s Tom Hogan said. “That’s why we are going to immediately resample systems determined to have the greatest potential to be affected by the temperature inconsistencies. We will prioritize this work based on potential risk factors and will be working with laboratories to analyze the samples as quickly as possible.”
The department said it will immediately provide training for workers to make sure water samples are kept at the proper temperature, evaluate past tests to see which compiled with temperature requirements, retest water systems soon if the temperatures were wrong and bring in an independent expert to review water sample handling procedures.
Federal guidelines call for water samples to be about 39 degrees when transported, but in some cases they were at room temperature.
The specific concern announced Thursday was over temperatures in which samples were held to determine the presence of organic chemicals, such as fertilizers, solvents and common household chemicals. The issue also potentially involves samples taken to determine the presence of inorganic compounds for which holding temperature may be an issue, substances such as cyanide and nitrite.
There apparently were no temperature problems when the department took samples to check for viruses or other infectious agents.
Last year, the department tested about 2,800 drinking water samples for organic chemicals, about 30 percent of the total number of water samples tested.
Department officials said the higher temperatures may have caused some samples to degrade and provide results lower than the true value.
“These practices should have been uniformly modified to comply with up-to-date (federal) guidelines, and the division did not do so,” Hogan said. “We take our responsibilities in this area very seriously, and we deeply regret this oversight. We are taking immediate steps to set this right.”
On the other hand, Hogan said that other state agencies have taken similar tests in public waters that indicate the risk to Minnesotans is limited.