Studies show that 90 per cent of pharmaceutical wastewater treatment plants release pharmaceutical residues into soil and water, providing ideal breeding grounds for drug-resistant bacteria
Antimicrobial resistance (AMR) is a global public health problem. In a 2014 report, the then Assistant Director-General for Health Security of World Health Organisation (WHO), Dr Keiji Fukuda, called it "a problem so serious that it threatens the achievements of modern medicine."
Antibiotics are active pharmaceutical compounds used to control bacterial infections. They had revolutionised medicine at the time of their discovery. However, the emergence of new bacterial resistance mechanisms against them now challenges our ability to treat even common diseases. This results in issues such as increased treatment costs, long hospitalisation, and higher mortality. In India, AMR is mainly caused due to use of broad spectrum antibiotics, fixed dose combinations, and application of antibiotics for veterinary purposes.
Recent reports have revealed that pharmaceutical industries also contribute to this issue. Eighty per cent of the antibiotics used globally are produced in countries such as India and China and studies show that 90 per cent of pharmaceutical wastewater treatment plants release pharmaceutical residues into soil and water, providing ideal breeding grounds for drug-resistant bacteria.
There is now an urgent need for AMR researchers to work with scientists and industries across disciplines to find out the AMR transmission and control mechanisms. Effective treatment and management of wastewater from the pharmaceutical industry will also help in overcoming AMR.
Microbial enzyme based treatment option
In comparison to conventional wastewater treatment technologies, advanced treatment methods such as reverse osmosis, nanofiltration, and membrane bioreactors have shown to be promising processes for cleaning micropollutants with nanogram per litre (ng/L) concentration levels.
For the last two decades, the deployment of enzymes for bioremediation of various pollutants has been studied extensively. Various types of bacteria and fungi produce active enzymes. These enzymes are grafted in membrane filters or used in membrane bioreactor to remove harmful and toxic pharmaceutical pollutants which finally help in wastewater purification. Generally enzymes such as laccase, lipase, ligninnases, and cellulose are used in inactivation of antibiotics in wastewater effluents; consequently prevent the pollution of the environment.
TERI's method
The Energy and Resources Institute (TERI), in collaboration with The University of Pannonia, Hungary, is on the verge of developing a simple treatment system to remediate pharmaceuticals from wastewater. According to preliminary results, immobilisation and/or binding of well-chosen enzymes to membranes can effectively break down/eliminate micro-pollutants. In this innovation, the bacterial enzymes embedded in the membrane reactor help degrade antibiotics.
Nanomaterials are used for complete removal of bio-transferred intermediate and for elimination of antimicrobial resistant bacteria from wastewater. These fast, simple, and versatile enzymes treat wastewater without toxic by-products or generating biomass. They also require low energy and operational costs. This treatment option has finally led to decontamination of antibiotic residues in wastewater in the initial phase of lab-scale development. The enzymatic membrane reactor system will be further up-scaled and commercialized after eliminating existing process limitations. The projected enzymatic technology leads to economically viable and greener processes, while treating emerging pharmaceuticals in wastewater.