Summary
This long-term field study examined how municipal sewage sludge applications alter soil antibiotic resistome composition and diversity over two decades. The research demonstrated that annual sludge applications pose greater risk than infrequent applications, driving both continued introduction of urban-derived resistance genes and stimulation of intrinsic soil ARGs, with substantial attenuation of certain sludge-specific resistance determinants (particularly aminoglycoside and tetracycline genes) following soil incorporation.
UK applicability
This study's findings are directly applicable to United Kingdom agricultural practice, as sewage sludge application to farmland is a widespread soil amendment strategy in the UK. The results inform risk assessment and regulatory frameworks governing sludge recycling and may warrant consideration in revising application protocols to minimise long-term accumulation of clinically relevant resistance genes in British agricultural soils.
Key measures
High-throughput quantitative PCR quantification of ARGs conferring resistance to multidrug, β-lactam, MLSB, tetracycline, vancomycin and aminoglycoside antibiotics; MGE marker gene abundance; ARG and MGE composition and diversity metrics in sludges and amended soils
Outcomes reported
The study quantified the abundance, composition and diversity of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) in soils receiving different sewage sludge application regimes over 20+ years. It measured attenuation of sludge-derived ARGs following soil incorporation and assessed the differential impact of annual versus historical sludge applications on soil resistome profiles.
Topic tags
Dig deeper with Pulse AI.
Pulse AI has read the whole catalogue. Ask about this record, its theme, or how the findings apply to UK farming and policy — every answer cites the underlying studies.