A cancer-causing chemical has been found in unusually high levels in Long Island's drinking water supply.

Dennis Kellerher, of H2M Architects and Engineers, says 1,4 dioxane has been found in higher numbers in Long Island water compared to the rest of the U.S. during testing. His company was in charge of most of the Island's testing for the chemical.

Many believe that one of the reasons 1,4 dioxane was discovered in higher levels was because Long Island was the epicenter in manufacturing of commercial degreasers in the past.

Environmental advocate Adrienne Esposito says the problem isn't just in our past - the chemical can be found in household products used every day like bath gel, laundry soap and dish soap.

There are currently no federal standards for acceptable amounts of 1,4 dioxane in drinking water, even though the effects are potentially deadly. Esposito says the chemical can cause liver, kidney, nasal cavity, breast or skin cancer.

Pat Halpin, chairman of the Suffolk Water Authority, says its lab began testing for the presence of 1,4 dioxane in the early 2000s.

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The lab is required by law to test for 149 contaminants. The Suffolk Water Authority tested for 400 contaminants, resulting in 16,000 results in 2018.

The lab's manager, Kevin Durk, says raw groundwater is brought to the facility where it is isolated, combined with a solvent then analyzed to determine the presence of 1,4 dioxane.

The state is proposing reducing the levels of 1,4 dioxane drastically by 2020, and water officials say the timetable is unreasonable. Environmentalists argue that the push is necessary.

Gov. Andrew Cuomo signed legislation banning the sale of household products containing 1,4 dioxane by January of 2020.

The American Cleaning Institute, which represents soap, detergent and cleaning supply manufacturers says it's disappointed by the legislation.

A statement released by the organization said in part, "We had offered language to make this bill workable and responsible. Regrettably, it was not included in the legislation that was signed into law."