Hundreds of rivers around the world are contaminated by antibiotics, according to the largest study of the problem ever.
711 water samples from rivers in 72 countries on six continents have been investigated by researchers.
One or more types of antibiotics were found in two-thirds of the samples.
– The results are a wake-up call and quite worrying. They show extensive pollution of the world’s river systems, says researcher Alistair Boxall at the University of York, who has helped lead the work.
The research results were presented at a conference in Helsinki on Monday. In over one hundred places, antibiotic levels have been measured which exceed the limit values set by the pharmaceutical industry itself.
The Danube and the Thames
The problem is greatest in developing countries in Asia and Africa. One place in Bangladesh measured concentrations of metronidazole – a widely used antibiotic – that was 300 times higher than recommended.
But European rivers are also polluted. Antibiotic levels were above the 8 percent limit of the sites examined in Europe, according to The Guardian newspaper.
Of the European rivers, the Danube was the most polluted. One place in Austria found seven different types of antibiotics in the water.
In the Thames, which runs through London and is initially considered one of Europe’s cleanest rivers, five different types of antibiotics were found.
River pollution can help to make bacteria resistant to antibiotics. In practice, this means that medicines for common diseases may stop working.
Antibiotic resistance is a growing problem that has gradually gained more attention. The main reason is believed to be that antibiotics are used too often and in the wrong way both in health care and in agriculture.
But antibiotic pollution in nature also plays a role. The pollution comes from both pharmaceutical factories, water purification plants and faeces and urine from humans and animals.
– It’s quite scary and depressing. In large parts of the environment, antibiotic levels can be high enough to affect resistance, Boxall says.
The World Health Organization (WHO) has warned that more and more types of antibiotics are deteriorating and that new ones are urgently needed.
Unless action is taken, 10 million people can die every year as a result of antibiotic resistance by 2050, according to a UN report presented last month. The financial consequences can be in line with the financial crisis.
– Small occurrence in Norway
Already today it is believed that at least 700,000 people die each year from diseases caused by microorganisms that have become resistant to drugs.
– There is already a major public health problem in Europe, especially in the south and west. Currently, the incidence in Norway is so small that we do not notice it as a significant problem, but we expect that it will also increase here as it has become an even greater challenge in other countries, ”says researcher Petter Elstrøm at the Norwegian Institute of Public Health to Aftenposten.
A European study nonetheless suggests that 70 people died in Norway in 2015 as a result of antibiotic-resistant bacteria.
In addition to the fact that antibiotic pollution in nature makes bacteria more dangerous, the consequences for wildlife can be great.
Boxall and his colleagues found rivers in Kenya where there was so much antibiotics that fish could not live there. The researchers are planning a new study of how fish, invertebrates and algae are affected by the remnants of medicine.