RIO DE JANEIRO (Reuters) -- Fifty tons of dead fish washed onto the picturesque beaches of Rio de Janeiro this week, the latest in a series of environmental mishaps that are spoiling the city's natural beauty, officials said Wednesday.
Thousands of smelly sardines coated beaches in the northern part of the city, which hosted the environmental Earth Summit in 1992. The fish floated belly-up in the waters near the international airport.
While officials investigated possible causes for the kill, ranging from pollution to illegal fishing practices and heavy rains that reduced the water's salinity, residents agreed on the result.
"Rio's reputation is being ruined and it's not that great to live in the middle of it either," said Ruy Marco, a hotel clerk.
The Earth Summit's host city has been home to ecological disaster so far in 2000.
In January Brazilian oil giant Petrobras accidentally dumped 338,000 gallons (1.4 million liters) of fuel oil in Rio's landmark Guanabara Bay, a spill that will take at least 10 years to recover from, according to specialists.
Raw sewage pumped daily into the ocean off of Copacabana and Ipanema beaches has already forced officials to ban bathing in most of the world-famous waters, leading cartoonists to compare the bay to a toilet.
During the Carnival parties in March, sewage and a sudden drop in oxygen levels killed 100 tons of fish in a picturesque lagoon nestled behind Ipanema beach. Tourists and residents were forced to cover their noses with bandannas for days while officials cleaned the area.
"We're still investigating the cause of this latest round of dead fish," Laura Franca, a spokeswoman for the local fishing federation, told Reuters Wednesday. "Pollution is just one hypothesis, but anyway it's a shame."