PORTLAND, Maine — Maine and parts of southern New Hampshire have become the focus of several studies looking at how arsenic may impact health.

That region has high levels of arsenic that occurs naturally in bedrock. While there are similar arsenic hot spots in other parts of the country, those regions are served by municipal water systems which under federal law must remove the arsenic.

Arsenic has been tied to health problems, including many bladder, lung and other types of cancer, cardiovascular disease, circulatory problems and developmental problems in children.

The Maine Sunday Telegram reports that Columbia University and the University of New Hampshire have been studying the potential link between arsenic exposure in children and the development of cognitive skills. University of Maine researchers have been looking at whether there’s a link between arsenic in drinking water and asthma. Maine, New Hampshire and Rhode Island have the highest asthma rates in the nation.