Legislators are considering sharply lowering how much arsenic New Hampshire allows in drinking water – but regulators said in a committee hearing Wednesday it'd be easier said than done.
Right now, New Hampshire uses the federal arsenic limit of 10 parts per billion in drinking water.
Rep. Mindi Messmer, a Rye Democrat, says that’s driving the state's high rates of bladder cancer.
Studies have found that such a limit for carcinogens like arsenic can lead to anywhere from hundreds to thousands of related cancer cases per million people.
The National Institutes of Health says New Hampshire, Maine and Vermont have a 20 percent higher bladder cancer rate than the national average. And in 2016, the NIH said this could be due to the prevalence of old, dug drinking water wells, which can contain arsenic that has leached from bedrock and pesticide runoff.
Messmer's new bill would lower New Hampshire’s arsenic limit to four parts per trillion, which she says would reduce arsenic-related bladder cancer rates to one in a million people, according to EPA guidelines. That level is currently a goal, but not a requirement, in California.
But Paul Susca of the Department of Environmental Services says current water testing and treatment systems can't actually handle that low a level.
"There's more to it than simply the health risk, and it has to do with technological feasibility and cost,” he says.
Susca says DES would rather consider a more moderate reduction to the arsenic standard, such as 5 parts per billion, which has been used in New Jersey since 2006. He says that limit could prevent a couple dozen cancer cases, but would still cost public water systems $2 to $3 million a year to implement.
The bill was referred to the legislative budget office for a full cost analysis.
(Read the DES's written testimony to the House Resources Committee here.)