Proclivities for prevalence and treatment of antibiotics in the ambient water: a review

In the intial two decades of the twenty-first century, antibiotic (AB) resistance in human pathogens has emerged as a major challenge for water, sanitation, and public health. Considering these challenges, we critically reviewed AB-related studies with particular emphasis on their (i) patterns of consumption, (ii) pathway prevalences and environmental implications in ambient waters, and (iii) benefits and limitations of existing AB removal/purging techniques. We found that lifestyle, land use, urbanization, the ease of availability, and the tendency of the medical practitioners to recommend ABs are the key factors governing the AB use pathway and enrichment in the environment. In the developing world, the most prevalent group of ABs is quinolone, whereas in the developed world, older-generation AB groups are most prevalent. Further, enormous variability in the consumption of ABs around the globe is explicitly highlighted in this study. Ciprofloxacin has been reported in the highest concentration among all the ABs with 28-31 mg L(-1)in the raw wastewater of the Indian subcontinent. We found that adsorption may be one of the most efficient AB removal techniques, and NaOH-activated carbon prepared from Macadamia nut shells is the most effective adsorbent identified to date. The literature showed that the Langmuir isotherm and pseudo-second-order kinetic model explain the AB adsorption mechanism most effectively. The future challenge lies in developing advanced protocols and markers to prioritize the strategy and simulate the ecotoxicities of the individual and a mixture of ABs.