Antibiotics in wastewaters: a review with focus on Oman

The occurrence of antibiotics in treated wastewater effluent has been a concern worldwide for various reasons: most importantly development of antibiotics resistance by bacteria and other microorganism, impact of antibiotics on animal life in surface water and likely consequences on humans if treated wastewater is used for drinking water supply through the process of managed aquifer recharge (MAR). Another potential area of concern is the uptake of these antibiotics by crops irrigated by treated wastewater. In Oman, wastewater treatment and reuse is pursued vigorously as a government policy. Treated wastewater is used for crop irrigation following government regulations, MAR is being contemplated and practiced in small scale and release of such waters in the ocean takes place from time to time. Some tests have been conducted on the wastewater effluent around the world to verify and detect the concentration of antibiotics in wastewater effluent. In the Sultanate of Oman, very little research has been performed on the occurrence of antibiotics in treated wastewater, removal efficiencies of treatment processes and development of antibiotics resistance. It is expected that wastewater reuse will increase substantially due to expansion of sewerage network in the capital city as well as many other cities and towns. As such, it is imperative that research be undertaken to find out various issues related to commonly used antibiotics such as ciprofloxacin, norfloxacin, erythromycin, linezolid, penicillin, ampicillin, chloramphenicol, streptomycin, minocycline, tetracycline and sulfamethoxazole in Oman and their ultimate fate through the treatment process. In addition, the development of guidelines is crucial in amounts of antibiotics acceptably occurring in treated wastewater effluent and if they could be suitable for agriculture without causing any harm. A review of the available literature and data are provided in this article. Research needs have been identified.