Flushable wipes are becoming increasingly popular for use in New Zealand homes, but they're the bane of many sewerage systems and testing has found that they shouldn't be flushed at all.
A joint Consumer New Zealand and Choice Australia study has found that many of the products do not break down in water at all - even when agitated for more than an hour.
The consumer organisations tested 11 "flushable" wipe products - including those for personal use and those for cleaning the household.
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Products available in New Zealand were Sorbent Kids Flushable Wipes, Sorbent Clean and Fresh Wipes, Kleenex Cottonelle Flushable Cleansing Cloths, Vagisil Feminine Wipes, Janola Flushable Wipes and Harpic White and Shine Flushable Wipes.
In comparison, the study found toilet paper broke down within minutes of being placed in the machine, and had completely broken down within 70 minutes.
Consumer New Zealand head Sue Chetwin said if the wipes did not degrade after being agitated for an hour, manufacturers should not advertise them as flushable.
"Our research found these wipes don't break down readily and can end up causing costly plumbing headaches, both for consumers and local councils," she said.
"In our view, manufacturers shouldn't be claiming these products are 'flushable' when they may not break down in real-world conditions. We'd like to see the claims removed from product packaging.
"If you're using these wipes at home, our advice is don't flush them - even if the label says you can."
Chair of the Plumbers, Gasfitters and Drainlayers Board, Peter Jackson, said the biggest problem with the products not breaking down was that they caused blockages at home and at municipal facilities
"They're being sold as flushable and that's the problem - because they're really not."
Mr Jackson said that he'd seen "a hang of a lot" more flushable wipes appear on supermarket shelves since he'd started in the plumbing industry 50 years ago. Over that time, the amount of water used to flush toilets had decreased, exacerbating the problem by causing the wipes to build up in pipes.
"They don't get flushed as far down the drain and they sit there - and the next thing you've got a blockage."
The best bet for consumers was to use unpatterned white toilet paper after doing the deed, he said.
A spokeswoman for Auckland's water and wastewater service provider Watercare said people flushing wipes was an issue that seemed to be growing - causing blockages and overflows in the city's sewerage network.
Furthermore, when combined with fats, oils, grease and sanitary products, the wipes could cause the development of 'fatbergs' - congealed buildups of products that don't break down in water.
"We urge Aucklanders to simply put all used wipes in the rubbish bin. The only things that should be flushed down the loo are human waste and toilet paper," the spokeswoman said.
Consumer New Zealand: https://www.consumer.org.nz/articles/flushable-wipes
• Kleenex Cottonelle Flushable Cleansing Cloths.
The company says the wipes are flushable, as they break up while moving through the system, but it recommend no more than two wipes should be flushed at a time.
"All our products are clearly labelled on pack to ensure consumers know how to dispose of them in the correct way."
• Sorbent Kids Flushable Wipes and Sorbent Clean and Fresh Wipes.
• Vagisil Feminine Wipes.
• Janola Flushable Wipes.
• Harpic White and Shine Flushable Wipes.