WESTON, Conn. (AP) Connecticut health officials say they've received numerous reports in recent years of arsenic and other contaminants in residential drinking water across the state, but a published report says little research on the source or location of the pollution is being done.

State Department of Public Health officials say well water contamination is a sporadic but statewide problem.

An estimated 400,000 private wells in Connecticut serve nearly 527,000 people, but it's not known how prevalent contamination is. The state only requires water testing when new wells are installed.

30 percent of 104 wells tested in Weston showed arsenic levels above acceptable limits, and some residents report health problems. In Stamford, arsenic was detected in 24 of 227 well water tests since 2010.