Synthetic antibiotic-resistant genes have found their way into microorganisms in Chinese rivers.

Min Jin and Jun-Wen Li at the Key Laboratory of Risk Assessment and Control for Environment and Food Safety in Tianjin, China, and their colleagues extracted microbes from the water of six rivers. They then looked for lab-made DNA fragments called plasmid vectors, which are used as genetic tools to introduce and express particular genes in cells. In all six rivers, the authors found microbes containing genes from plasmid vectors widely used in biotechnology, as well as synthetic versions of the β-lactam antibiotic (blá) gene, which confers resistance to ampicillin.

The team warns that this plasmid-containing lab waste could be a source of animal and human antibiotic resistance.

Environ. Sci. Technol. http://dx.doi.org/10.1021/es302760s (2012)