World Cup soccer fans warned about Rio beaches

World Cup fans heading for Rio de Janeiro might want to think twice about swimming in the sea - as these shocking photos reveal the true extent of its sewage problems.

More than 400,000 tourists are expected to descend on Brazil's 'Marvellous City' next month but they might want to avoid the ocean.

Local photographer Eliseu Cavalcante snapped the destination's waterways - which are pumped with human excrement.

Only 40 per cent of sewage is treated in Rio - and the rest ends up in its rivers, lagoons and bays. 

And as these images show, it also ends up floating around on and near the beaches where tourists will be flocking. 

Cavalcante told website Rio Gringa that she wanted to raise the issue of sanitation at a time when more foreigners are paying attention to Brazil.

According to Global Post, the government plans to clean up the usually picturesque Guanabara Bay - where up to 100 tonnes of rubbish are dumped every day - ahead of the 2016 Summer Olympics - especially because of the water events involved.

Mario Moscatelli, a biologist who's been monitoring Rio’s waterways for decades, said more than £595m had been spent trying to clean up the bay in the past 20 years, but the situation has worsened.

'Not in my worst nightmares would I have imagined that the Brazilian authorities would have done this with the environment,' he said.

According to the city government's environment agency, 12 locations along beaches in Zona Sul — the most popular area for tourists - are unsafe for swimming due to the poor water quality.

Dr Daniel Becker, founder of the nonprofit Center for Health Promotion in Rio, said: 'In Rio, if you're going to the beach, you're going to sewage.'

He said exposure to raw sewage could cause illnesses such as diarrhoea and microbial diseases.

In April, the state government said it was cutting the Olympic clean-up budget from $1bn to £51m, according to Global Post.