Plastics seep from waste sites
Research shows microplastics can enter the environment from wastewater treatment.
Researchers in New Zealand have regularly sampled effluent from three wastewater treatment plants in the city of Canterbury, finding they are a significant source of microplastics in the marine environment.
The treatment plants are not currently designed to remove microplastics, but the researchers estimate that every day 240,000 microplastics enter the coastal environment from the effluent coming out of those three plants.
Wastewater becomes contaminated with microplastics due to the use of synthetic clothing and textiles and other plastic products, and the most common microplastics detected were polyester, polyethylene, and polypropylene.
The authors say further work is needed to better understand which microplastics are entering the treatment plants, and which are discharged in the effluent.
Like the treatment plants in New Zealand, wastewater plants in Australia and much of the rest of the world are the final port of call for water before it is released into the environment.