New Hampshire officials say hundreds of cases of lung, bladder and skin cancer could be avoided if private well owners had their drinking water tested for arsenic.

The report by Dartmouth College and the state departments of health and environmental services estimates that 450 to 600 cases of cancer could be avoided through testing and treatment of water found to have unhealthy levels of arsenic. The estimates are based on the number of wells that have tested positive and cancer rates in the state.

Nearly half the state’s population gets its water from private wells.

Arsenic is a naturally occurring carcinogen that is odorless, colorless and tasteless.

“Over the last 25 years, the number of diseases associated with arsenic has increased, the parts of the body affected by arsenic-mediated diseases have increased and estimates of what constitutes a safe long-term dose of arsenic have decreased,” said Mark Borsuk of Dartmouth’s Thayer School of Engineering and project leader on the report.