Google awards project that removes microplastics from water

Irish teenager, Fionn Ferreira from Ballydehob, west Cork, has won an international science award for his project that removes microplastics from water.

The project, which secured the grand prize of $50,000, investigated a new method to extract microplastics of less than 5mm diameter from water. Microplastics are mostly used in shower gels, facial scrubs, soaps, toothpaste and abrasive cleaners.

At present, no screening or filtering for microplastics takes place in any European wastewater treatment centre. Microplastics enter the oceans and are mistaken by fish for food and enter the food chain.

Inspiration
His method was inspired by an article written by physicist, Arden Warner (Fermilab) who has used non-toxic oxide to clean up oil spills.

‘I used this method [to extract] microplastics, by adding oil to a suspension containing a known concentration of microplastics. These then migrated into the oil phase. Magnetite power was added and the resulting microplastic containing ferro-fluid was removed using strong magnets,’ the eighteen-year-old explained in his submission.

His hypothesis was that the extraction method would remove 85% or higher of microplastics in samples.

Marine pollution
Living near the coast, Fionn was alarmed to find out how many microplastics enter wastewater systems and consequently the oceans.

‘This inspired me to try and find a way to remove microplastics from waters before they even reach the sea,’ he explains.

His first challenge was to measure the concentration of microplastics in water, and to build a spectrometer to measure the levels.

In his chemistry class he learned that like-charges attract like-charges, and having read Dr Warner’s method of using magnetite power to clean up oil spills, the budding scientist had an idea:

‘This made me think that a combination of oil and magnetite would allow me to remove plastics from water.”

Results
Ten different types of microplastic suspensions were tested and three extractions were carried out for each of the four different volumes of oil used in each extraction. A total 120 captures were taken for every extraction.

‘I am 95% confident that the mean reduction of microplastic will lie between 86.6% and 88.7%.’

But he adds that the most effective way to reduce microplastic pollution is to use less plastics in the first place.

‘The reality is that more and more of the products we use contain plastics and potentially degrade into microplastics before entering our wastewater.

‘It is therefore essential that we find efficient and effective ways of extracting microplastics from wastewaters before they reach our watercourses and ultimately our oceans.’