Investigating the environmental risks from the use of spray-dried cephalosporin mycelial dreg (CMD) as a soil amendment.
Cephalosporin mycelial dreg (CMD) is a by-product of the pharmaceutical industry. Spray-drying is widely used for the dewatering process prior to the application of CMD as a soil amendment. However, the potential environmental behaviors and risks of spray-dried CMD amendment remain unclear. Here, a lab-scale incubation experiment was conducted to investigate the salinity, phytotoxicity, introduced antibiotics, heavy metals and the potential impacts of resistance genes in CMD-amended soil. Spray-dried CMD amendment generally increased soil salinity and only high dosed soils showed phytotoxic effects at the end of the incubation period, implying the physiological damage to plant growth. The introduced antibiotics quickly degraded over time, indicating a relatively low environmental persistence. Heavy metal slightly increased in soil receiving spray-dried CMD, and regulations should be developed to avoid metal accumulation. A decreased diversity and distinct patterns of β-lactam resistance genes as well as a dose-effect of their enrichment were observed in CMD-amended soil, which might be partially explained by the specific metals and introduced antibiotics. Antibiotic resistance genes in soil may be a valuable tool for evaluating the environmental risk associated with use of CMD as a soil amendment.
['Cai|Chen|C|', 'Gong|Picheng|P|', 'Wang|Yue|Y|', 'Wang|Mengmeng|M|', 'Zhang|Bo|B|', 'Wang|Bing|B|', 'Liu|Huiling|H|']
D000900:Anti-Bacterial Agents D001419:Bacteria D029741:Brassica rapa D002511:Cephalosporins D003890:Desiccation D004352:Drug Resistance, Microbial D005308:Fertilizers D007220:Industrial Waste D019216:Metals, Heavy D012306:Risk D054712:Salinity D012989:Soil Pollutants
Environmental risk Cephalosporin mycelial dreg (CMD) Amendment β-Lactam resistance genes