Here’s a compelling reason to start composting: your municipal solid waste is producing airborne antibiotic-resistance genes. Duhn duhn duhhhhn.
But actually, this news is quite frightening. According to a study published in ACS' Environmental Science & Technology, trash such as plastic, food scraps, and lawn clippings that end up in landfills or being incinerated are causing a serious threat to public health. Landfill and incineration are the main disposal practices for municipal solid waste (MSW), and while scientists have previously understood that they can act as reservoirs of antibiotic resistance genes (ARGs), the idea that these genes could be airborne is new.
Researchers So Yi Luo, Xiangdong Li and colleagues investigated this idea at the municipal solid waste treatment system of Changzhou, a city in eastern China. They collected inside and ambient air samples (PM10 and PM2.5) and potential source samples (leachate and solid waste) in the municipal solid waste treatment system, including the air from a landfill site, a municipal solid waste incinerator and two transfer stations.
When they analyzed their samples, they found that air from both the municipal incinerator and the landfill site had elevated levels of particulate matter and bacteria compared to upwind sites.
As the authors write in the study, “Forty-one antibiotic-resistant bacteria (ARB) harboring blaTEM-1 were isolated, and the full-length nucleotide sequences of the blaTEM-1 gene (harbored by identical bacillus) from the air (downwind samples) were 100% identical with those in the leachate and solid waste, indicating that the MSWT system was the important source of dispersing bacteria and associated ARGs in the ambient air.”
These findings suggest that municipal solid waste treatment systems could be transmitting antibiotic-resistance genes to nearby residents who breathe the air. The ARGs originate from residual antibiotics and tossed medications that end up in the trash which then leach into the municipal solid waste and spread their resistance to bacteria.
The authors urge further investigation of the propagation of airborne ARGs which could be leading to human exposure, saying it is a matter of public health for communities living near these facilities.