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Title: Open Waste Canals as Potential Sources of Antimicrobial Resistance Genes in Aerosols in Urban Kanpur, India
Understanding the movement of antimicrobial resistance genes (ARGs) in the environment is critical to managing their spread. To assess potential ARG transport through the air via urban bioaerosols in cities with poor sanitation, we quantified ARGs and a mobile integron (MI) in ambient air over periods spanning rainy and dry seasons in Kanpur, India ( n = 53), where open wastewater canals (OCWs) are prevalent. Gene targets represented major antibiotic groups—tetracyclines ( tetA ), fluoroquinolines ( qnrB ), and beta-lactams ( bla TEM )—and a class 1 mobile integron ( intI1 ). Over half of air samples located near, and up to 1 km from OCWs with fecal contamination ( n = 45) in Kanpur had detectable targets above the experimentally determined limits of detection (LOD): most commonly intI1 and tetA (56% and 51% of samples, respectively), followed by bla TEM (8.9%) and qnrB (0%). ARG and MI densities in these positive air samples ranged from 6.9 × 10 1 to 5.2 × 10 3 gene copies/m 3 air. Most (7/8) control samples collected 1 km away from OCWs were negative for any targets. In comparing experimental samples with control samples, we found that intI1 and tetA densities in air more » are significantly higher ( P = 0.04 and P = 0.01, respectively, alpha = 0.05) near laboratory-confirmed fecal contaminated waters than at the control site. These data suggest increased densities of ARGs and MIs in bioaerosols in urban environments with inadequate sanitation. In such settings, aerosols may play a role in the spread of AR. « less
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The American Journal of Tropical Medicine and Hygiene
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National Science Foundation
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