Antibiotic-resistant bacteria in estuaries threatens seafood

Antibiotic pollution and resistance genes released into the natural environment by human activity are causing local bacteria to develop antibiotic resistance in estuaries. These findings by a team led by Professor Zhu Yongguan from the Institute of Urban Environment, Chinese Academy of Sciences have been published in Nature Microbiology.
Estuaries are bodies of water that lie between terrestrial/freshwater and marine ecosystems. The research team collected samples from 18 estuaries over 4,000 km of China’s coastline and found levels of antibiotic resistance genes (ARG) pollution at around one million resistance genes per gram of sediment, in some cases up to 100 million per gram.
The researchers found that the ARGs in estuarine sediments were diverse and abundant, with over 200 different resistance genes detected, 18 of which were found in all 90 sediment samples.
The study showed that the major cause of the accumulation of these genes in the environment is human activity and the failure of wastewater treatment plants to remove the ARGs during treatment.
Although the study focused on China, the authors emphasise that this is a global problem. Other areas of the world likely have similar concentrations of antibiotic-resistant bacteria. This is a serious human health risk as seafood like oysters and salmon are often sourced from estuarine habitats. People consuming seafood contaminated with antibiotic-resistant bacteria may be exposed to dangerous bacteria that have become resistant to all common antibiotics.
This study was published on 30 January 2017 in Nature Microbiology. It was also reported in Natural Science News, 31 January 2017. For details please click the following link: https://www.nature.com/articles/nmicrobiol2016270
– Third World Network