China consumes almost half the world's antibiotics - and they're coursing through its waterways
Study by national academy finds high levels of the drugs in northern rivers on the mainland and in the south near Hong Kong
The Pearl River is a soup of antibiotics, containing some of the highest concentrations of the medicine found in any of the mainland's waterways, the nation's top science academy has found.
Overuse of antibiotics in humans and animals was to blame for the high levels, according to a recently published paper, one of the first comprehensive studies of the domestic scale of the problem.
The mainland was the world's largest manufacturer and consumer of antibiotics, using about 162,000 tonnes of more than 200 varieties in 2013, it found. Consumption was almost evenly split between humans and animals, researchers said.
But overuse can be dangerous as it allows bacteria to build up a resistance to treatments, reducing their effectiveness over time.
"The usage of antibiotics in China is very high, it's almost half of the world usage when we compare it with international studies," said Ying Guangguo of the Guangzhou Institute of Geochemistry under the Chinese Academy of Sciences, and who lead the research.
The study focused on 36 kinds of the most common antibiotics, including amoxicillin and florfenicol. In this narrower range, the mainland used 92,700 tonnes in 2013. Some 53,800 tonnes entered the environment in the form of urine and excrement after various wastewater treatments, according to the report.
Researchers examined antibiotic levels in 58 river basins across the mainland and found concentrations were highest in the waterways around Beijing, Tianjin and Hebei province, where the population is dense and rainfall scarce.
But the Pearl River, which flows into the ocean past Hong Kong, had the most worrying levels in the south, partially due to the intense scale of farming in the region.
It also found that eastern China was discharging six times more antibiotics than the west, which again was due to population differences.
Ying said the government should step up regulatory control over the use of the medicines.
"Antibiotics are a very important drug prescribed by doctors, but in China, anyone can purchase it without a prescription in local pharmacies," he said.
"There is also no monitoring of antibiotics being used in animals. Local animal farm operators often add antibiotics into animal feed to prevent diseases and boost production."
The paper was published in the Environmental Sciences & Technology journal last month.
Online news portal Thepaper.cn cited research published by the Fudan School of Public Health in April that involved testing the urine of more than 1,000 children aged between eight and 11. Nearly 60 per cent of the samples contained some form of antibiotics. Of those, about a quarter had more than two types.
A study published last year by researchers at Princeton University in the United States found global use of antibiotics between 2000 and 2010 rose 36 per cent, with BRICS countries - Brazil, Russia, India, China and South Africa - together accounting for more than three-quarters of the increase.
It also found that by 2010, China was the second-largest consumer of antibiotics, after India and before the US.
An earlier version of this article wrongly stated that overuse of antibiotics can be dangerous as it allows viruses to build up a resistance to treatments. It should have read bacteria can build up resistance.