‘Flushable’ Wipes Flush Plastic to Sea and Shore

Researchers find that non-woven products are an underestimated source of microplastic in the marine environment.

Three scientists with plastic litter on the beach
(L to R) Dr Liam Morrison, Ana Mendes, Oisín Ó Briain at Grattan beach, Ireland.

 Aengus McMahon

Much like when we throw things in the trash and they miraculously disappear from our homes, the same wizardry happens when we flush things down the toilet. Out of sight, out of mind – a feat of magical thinking that allows us to continue creating waste with nary a twinge of accountability.

There are all kinds of things one should not flush down the toilet – like, see what happens when you “liberate” a goldfish in this manner. But what about items labeled as “flushable”? They must be OK, right? 

Well, you know where this is going. Recent research in Ireland looking at commonly flushed personal care products (wet wipes and sanitary pads, specifically) reveals that many of them not only clog sewers, but are also adding to the ocean plastic crisis.

The researchers from Earth and Ocean Sciences and the Ryan Institute at NUI Galway (NUI) found that sediments near a wastewater treatment plant were regularly strewn with microplastic fibers consistent with those from consumer wet wipes and sanitary pads.

At one of the sites they studied, they found 6,083 white microplastic fibers per kilogram (2.2 pounds) of sediment. Not to mention the presence of used wipes and pads entwined with seaweed along the shore.

plastic debris on the beach
Washed up sewage-derived debris including wet wipes and sanitary pad, mixed with seaweed. Morrison et al.

White fibers are tricky when assessing plastic waste because most water filtration systems used to capture these fibers are also white (in the Anthropocene epoch, camouflage is not just for clever insects). Thus, white fibers are underestimated, which is especially a problem given the global obsession with non-woven synthetic fibers.

And here’s the rub: 50% of the wipes labelled "flushable" in the study were shown to contain plastics. For a wipe to be considered flushable they are required to be comprised of plant-based polymers which degrade during the wastewater treatment.

“The lack of regulation for hygiene and sanitary products results in a failure to identify the plastic composition of these materials,” notes NUI. “This demonstrates the consequences of misleading labelling of non-woven textile personal care products.”

And not only that; microplastics can carry germs into the ocean – tiny little rafts for tiny little microbes.

"[The pandemic] may have brought its own challenges for the oceans including the increased use of disinfectant wipes during the pandemic which potentially may end up as microplastic fibres in the sea,” says lead researcher of the study, Dr Liam Morrison from Earth and Ocean Sciences and Ryan Institute at NUI Galway. “It is widely known that microplastics can act as vectors for contaminants including bacteria and viruses and are potentially harmful for public health and marine life."

This isn’t the first time we’ve heard of the horrors of flushed wet wipes. For years they have been clogging sewers, where they mingle and merge with oils to form so-called fatbergs; one needs only scant imagination to picture such a phenomenon. The challenges this presents to wastewater utilities is daunting.

And by the looks of it, it’s going to get worse. “Given the global distribution and projected growth of the non-woven textile industry (as non-woven textiles form the base material of many sanitary products), this is a concern,” notes NUI, adding that European production of these non-woven textiles for hygiene and sanitary products was over one million tonnes in 2016 alone.

According to the Great British Beach Clean 2019 Report published by the Marine Conservation Society, the quantities of wet wipes washing up on beaches in the UK has increased 400% in the last decade. 

Which all just goes to show that the wizardry of flushing things away is little more than a pipe dream.

The research was published in the international journal Water Research.