Interaction of cyanobacteria and microplastics polystyrene spiked with pharmaceutical drug-paracetamol.

The microplastics polymer-polystyrene, polyethylene, polyvinyl chloride, etc. are now recognized as potent threats to the aquatic system due to the Trojan horse effect i.e., they adsorb other pollutants such as pharmaceutical drugs, organic solvents, metals etc. and act as a vector or carrier. Polystyrene (PS) is one of the most usable plastics worldwide that abundantly contaminates the aquatic body. However, to date, only a few studies have focused on the eco-toxic effects of polystyrene in combination with other pollutants. Therefore, in the present study, the effect of polystyrene (pristine) and spiked with the emerging pollutant paracetamol (PCM) was studied on cyanobacterium- Nostoc muscorum. PS, spiked with paracetamol exhibited a higher adverse effect on the growth and biochemical constituents. Fluorescence intensities of confocal images of the samples decreased with increasing toxic effect of polystyrene when spiked with paracetamol. Increased laccase and esterase activity also indicated the degradation potential of Nostoc muscorum. The findings of present work suggested PS (Pristine and spiked with PCM) toxicity on primary producer of ecosystem and role of cyanobacterial degrading enzymes in bioremediation of PS. Therefore, it is better to "nip in the bud" the plastic pollution rather than to face a great environmental threat.