For the first time in 20 years, the state Health Department issued guidelines for three contaminants in drinking water that are considered carcinogens.

The new limits proposed are on PFOS, PFOA and 1,4-dioxane, and they are considered the strictest regulations in the nation. The limits for 1,4-dioxane are set to one part per billion, and for PFOA and PFOS the limit is set to 10 parts per billion.

Environmentalists say this is good news, and that Long Island has seen high levels of PFOS and PFOA.

The state is offering New York water companies $350 million in grant money to pay for filtration systems that will remove the three contaminants. Providers say that's a drop in the bucket, and the Suffolk County Water Authority says it has 40 wells that will have to be upgraded.

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The Suffolk County Water Authority says it has been preparing to remove the contaminants from the water, and it has the first approved facility in the state that removes 1,4-dioxane.

1,4-dioxane is a product found in laundry detergent and personal care products, while PFOS is found in firefighting foams and PFOA is used to make stain- and water-resistant material.

Long Island has the highest levels of those contaminants found in the drinking water. There is no set date as to when the regulations will go into effect.

A 60-day public comment period for the proposed standards starts July 24.