The drinking water on Long Island has “by far” the most emerging contaminants of any region in the state, according to a review of detections of the substances by the New York Public Interest Research Group.

The review, “What’s in My Water,” was done by the Albany-based group using data collected between 2013 and 2016, and it concluded that “one or more emerging contaminants” could affect the supplies of about 16 million New Yorkers. The review was released May 28.

The report cautioned: “It is unclear if certain detections are health concerns” but noted that some emerging contaminants were detected above federal health advisory levels.

An emerging contaminant is one that either wasn't known about in the past, wasn't detectable with available science or wasn't present in the supply, said Christopher Gobler, marine sciences professor at Stony Brook University.

Those contaminants include industrial chemicals from spills, wastewater and components in personal-care products like shampoo and detergent.

The Island’s state of drinking water contrasts with the supply serving New York City, which gets its water from upstate and has acquired land surrounding the reservoirs, protecting the supply. The drinking water on the Island comes locally from below ground.

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Among the recommendations in the group’s report: implement testing of the emerging contaminants for every water system maintained by the public, strengthen standards for potentially unsafe chemicals, mandate testing of private household wells and bar the use of certain chemicals until proved safe.

Long Island has some of the highest detections in the nation of chemicals like 1,4 dioxane, a solvent used to keep machinery greased that is also a byproduct of certain personal-care products. The chemical 1,4 dioxane is a likely carcinogen.

Gov. Andrew M. Cuomo, speaking Friday at his office in Manhattan, told Newsday in a response to a question about the report that water quality is “a very big problem, all across the state” and pointed to the state’s $3 billion program for testing, filtration and new pipes.

“I’m worried about the water quality all across the state. We’ve seen it in upstate New York. We see it on the Island. The Island tends to be worse,” he said.

His counsel, Alphonso David, said that $200 million of the money is available for municipalities.

Gobler, chairman of coastal ecology and conservation and professor at the School of Marine and Atmospheric Sciences at Stony Brook, said the quality of drinking water on Long Island varies.

Some jurisdictions — such as the Suffolk County Water Authority — are good stewards of drinking water, Gobler said. He stressed that the supply to the estimated 100,000 Long Islanders who live in homes with private wells unreached by public pipes should be tested regularly for contaminants.

"It's a misnomer to lump all of Long Island's drinking water into a single category," he said. "If you were to do an honest comparison of the data for the water that Long Islanders drink, you'll find plenty of supplies that compare favorably with New York City."

Dennis Kelleher, a spokesman for the Long Island Water Conference, which represents the area’s drinking water providers, said in a statement following the report: “Long Island’s drinking water providers work tirelessly to ensure tap water meets or exceeds all state and federal standards. We are working closely with regulators on all new standards to ensure the health and safety of our residents.”

Adrienne Esposito, the executive director of Citizens Campaign for the Environment, said she wasn't surprised by the report.

"Tell me something I don't know. I don't need a report to tell me that Long Island has drinking-water challenges that surpass the other parts of the state," she said. "I don't think it's surprising to anybody who actually lives here."

She said the contaminants come from the legacy waste of Long Island's industrial past, but also "the greater challenge today is sustaining a water supply that 3 million people live on top of. We discharge our sewage into our drinking water. We have all our surface activities," including pesticides, fertilizers and household chemicals.

Said Esposito: "The point is that everything we do on Long Island impacts the quality of the water underneath our feet."