An investigation by the charity Electrical Safety First found that Ebay and Facebook Marketplace are failing to prevent recalled washing machines being listed for sale.
The charity posted dummy listings of recalled Whirlpool washing machines on eBay and Facebook Marketplace. Neither of the sites had measures in place to prevent recalled products from being listed for sale.
A dummy listing on eBay went undetected for three and a half days, while another remained on Facebook Marketplace for a whole week before Electrical Safety First deactivated it.
Martyn Allen, technical director at the charity, said: 'The shameful lack of measures in place to prevent recalled products being listed online demonstrates marketplaces aren't even taking some of the most basic steps to protect consumers.
'We hear time and time again how these sites have algorithms in place to prevent dangerous listings going live, yet our investigation proves that some of the most simplistic checks aren't in place.
'Model numbers and serial numbers must be made a mandatory field when listing white goods, to ensure recalled products aren't for sale on these sites.'
Sue Davies, head of consumer protection at Which?, said: 'It's totally unacceptable that products which pose a potentially serious safety risk can be listed for sale on online marketplaces with such ease, and exposes just how necessary it is to strengthen consumer protections in this area.
'Whirlpool must work much more effectively with online marketplaces to ensure that recalled machines are quickly removed from sale, and the government should make these sites take legal responsibility for preventing unsafe products from being sold.'
A spokeswoman for eBay said: 'If an item can be legally sold but is subject to a recall, sellers must include appropriate information about the recall within the listing.
'Safety is our priority, and between October 2018 and October 2019 our filters automatically blocked five million listings from entering the marketplace on product safety grounds - eBay works with organisations around the world including the EU market surveillance authorities and Westminster Trading Standards.
'If any of these authorities informs us that a product is dangerous, we ban it on all our marketplaces globally and inform and educate sellers on the ban.'
A Facebook spokesperson told the Mirror Online: 'We do not allow the sale or purchase of recalled products on our platform and are in the process of improving our systems to find and remove these types of listings on Marketplace.
'When we become aware of listings or products that violate our policies, we immediately take action.'
The recall covers Hotpoint and Indesit washing machines produced between October 2014 and February 2018. You can use Whirlpool's to find out whether your machine is affected. We also want to hear from owners of the affected washing machines about their experience of the recall.
Whirlpool advises owners of recalled models to unplug the machine and register with Whirlpool for a free replacement, or a free repair.