The state Health Department is warning of the dangers of being exposed to the Gowanus Canal, one of the country's most polluted waterways. NY1's Jeanine Ramirez filed the following report.

The graffiti says "It Came From The Gowanus," a nod to mythical creatures supposedly living in the murky water. 

PCBs, fuel, sewage and other contaminants have been seeping into the canal for decades. 

And now, a state Health Department report confirms what many suspected: This water is hazardous to your health.

"This report is definitely a warning for the community," said Sean Dixon, staff attorney with Riverkeeper.

Activist Christopher Swain took a dip in the canal two years ago to highlight its plight.

The report says swimming here can make you sick, and even skin contact with the water poses risks. 

"Water from the Gowanus Canal contains microorganisms, such as coliform bacteria, and likely contains viruses and parasites that can make a person ill if they enter the body," the report says. 

And, the report adds, with chemicals like benzene, prolonged exposure over a period of years could increase the risk of cancer.

The report used data collected from sampling the air, water, sediment and fish from the canal. It says people have been seen fishing here, but that eating anything caught can be dangerous.

The report finds that breathing the air is OK, but environmentalists are challenging that conclusion.

"Everyone who lives around the Gowanus knows that when it's sunny out, when there's a fresh oil spill, when there's sewage coming out of the CSOs, the combined sewer doors that are just a couple hundred feet from where we're standing now, the air quality can deteriorate, and it can deteriorate rapidly," Dixon said.

The canal's bad reuptation hasn't stopped a boom in development along its banks, and an increase in people who canoe, kayak and paddleboard here, even with obstacles like a half-sunken boat. The report says recreational boating is fine.  

"We've been leading thousands and thousands of voyages on this canal. I'm happy to see that's it says it's quite safe to kayak and canoe on the Gowanus Canal," said Owen Foote, co-founder of the Gowanus Dredgers Canoe Club.

A half-billion-dollar federal cleanup of the canal is supposed to be completed in 2022. Based on the report, there is a lot of work left to do.