**8. Complete Remediation of Environmental Antibiotic Residues, Resistant Bacteria and Resistance Genes**

Considering these issues and also that the normal photocatalysts used for disinfection are expensive materials like silver (Ag), titanium (Ti) etc., there was a need to develop photocatalysis based on inexpensive resources. Our research group has developed a technique using cheap resources like iron (Fe) or kaolinite nanoparticles and sunlight or visible light, that results in complete disinfection of multi-drug resistant pathogenic enteric bacteria and *Salmonella* from natural waters such as from ponds, rivers, lakes, tap water etc. [47–49].The same technique using the cheap resource of Fe and sunlight is also successful in 100% decontamination of environmentally highly stable antibiotics like ciprofloxacin from natural waters [50].This technique using sunlight is also useful with the conventional expensive

photocatalysts [51]. Further, for this technique, we have been able to show that the genetic resistance material gets completely degraded by this technique and in the process, we have also developed an insight into how the resistance gets broken down [49,52].
