The waters on New Jersey's Long Beach Island reopened Sunday, after medical waste washed ashore late Saturday morning.
LBI health officials closed the waters up to the high-tide line along most of the 18-mile-long summer resort as syringes were found in multiple locations.
But Sunday morning, Long Beach Township Mayor Joe Mancini told NBC 4 New York the beaches reopened at 10 a.m.
"We are watching closely, all good for now," Mancini said in a text message.
In nearby Harvey Cedars, Mayor John Oldham also reported lifeguards were letting people back into the water.
The wash-up of needles was blamed on last week's heavy rains in the New York City area.
LBI Health Director Tim Hilferty said the rains overtaxed the storm water and sewer lines, and since many diabetics simply discard their insulin syringes into the toilet, the medical waste bypassed sewer plants and emptied directly into New York Harbor.
Hilferty said as it all floated out to sea, strong winds, along with currents, washed the needles all the way down to LBI.
Environmentalists called it a "devastating start" to New Jersey's summer beach season, and to LBI, which gets more summer tourists than any comparable stretch of sand along the Jersey Shore.
"It is a harsh reminder reminder that federal and state cuts to environmental monitoring and tracking down of pollution sources are a threat to people and the economy," said Cindy Zipf, of the group Clean Ocean Action.
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