Health officials in Brazil are warning of a new health threat for Olympic athletes in addition to the already life-threatening zika virus — polluted water.

Brazil’s government made a promise seven years ago to reduce the amount of water pollution and waste that covers Rio’s Guanabara Bay. Officials admit their efforts have been less than effective and the threat of contamination and pollution is worse than initially anticipated.

As if Brazil doesn’t already have enough problems. This revelation comes on the heels of news that the Olympic village isn’t ready for athletes to move into. Reports of clogged toilets, gas smells, and other issues have been reported by coaches and teams.

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The New York Times reported that recent tests by government officials and scientists revealed pathogens in several of the city’s water sources, causing diarrhea, vomiting, and can even lead to death for people with weak immune systems.

Researchers also found serious contamination at popular beaches frequented by tourists, including the half-million Olympic spectators between events.

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The unsafe waters are particularly concerning for Olympic marathon swimmers, sailors, and windsurfers.

“Foreign athletes will literally be swimming in human crap, and they risk getting sick from all those microorganisms,” said Dr. Daniel Becker, a local pediatrician who works in poor neighborhoods. “It’s sad, but also worrisome.”

The International Olympic Committee said that in many places the city’s waters are filthy, but the areas where athletes will be competing meet World Health Organization safety standards. Even waters with higher levels of contamination pose only a small threat to athletes sailing or swimming because there will be limited contact with the water.

Athletes, however, are not thrilled to be competing in such disgusting waters. Those preparing for the Games have long expressed concern that waterborne illnesses could hinder their Olympic dreams.

“Welcome to the dump that is Rio,” said Germany’s sailing team in an assessment of the Games’ location.

Brazil’s athletes don’t disagree.

“It can get really disgusting, with dog carcasses in some places and the water turning brown from sewage contamination,” said Thomas Low-Beer, a Brazilian athlete who sails in the bay.

An investigation by The Associated Press last year recorded disease-causing viruses in some tests that were 1.7 million times the level of what would be considered hazardous on a Southern California beach.

The biggest problem Brazil is facing with contaminated water is useless efforts. Since the 1990s, Rio’s officials have spent billions of dollars on their efforts with no results.

Renata Picão, a microbiologist at the Federal University of Rio, has refused to step foot in the water since she began sampling it three years ago.

She said the pathogens likely come from local hospitals that discharge untreated waste. Although super bacteria might not pose a threat to healthy people, the organisms can remain in the body for years cause serious problems if the person becomes sick down the road.

She remains skeptical about future cleanup efforts, though.

“If they couldn’t clean things up for the Olympics, a once-in-a-lifetime opportunity, I’m afraid it might never happen,” said Picão.