Amid continuing worry about pollution at open-water sites for the 2016 Rio de Janeiro Olympics, a new study shows swimmers and boaters could face serious health risks.
The venues where numerous events will take place are tainted with human sewage, according to tests conducted over five months by the Associated Press.
The situation remains a concern to the International Olympic Committee.
"On the one hand we see great progress, on the other there is no time to lose," IOC President Thomas Bach told reporters this week.
Earlier this year, Brazilian officials acknowledged they would fall short of their goal to greatly decrease pollution in Guanabara Bay, where sailors and windsurfers will compete.