Managing Global Resources for a Secure Future

Azithromycin (AZ) is a commonly prescribed antibiotic commonly found in municipal biosolids and identified as an EPA compound of interest. The land application of municipal biosolids is an agronomically beneficial practice, but is also a potential route of trace organic contaminant (TOrC) introduction into soils. Data are lacking describing the retention and release characteristics of biosolids-borne AZ, making it difficult to evaluate the risks of land application of municipal biosolids materials. Here, we determine the AZ sorption and desorption coefficients for nine biosolids materials via batch sorption/desorption experiments. This research revealed a significant AZ sorption variance in biosolids, likely due to the biosolids’ varying physiochemical characteristics. Desorption also depended on biosolids, but was highly hysteretic.