TikTok and Temu have pulled cheap electric heaters from their online stores after Which? found they could explode or start house fires.
The consumer group tested eight heaters, the cheapest of which was £7.20, and found most did not meet UK safety standards.
It said the devices, some of which had been promoted by influencers on TikTok, posed “a serious safety risk” to users.
TikTok and Temu both said customer safety was their priority.
However, despite both companies removing the items from sale, Which? said it had found that more similar listings had since appeared in their place.
Temu and TikTok, though its Shop platform, have emerged as rivals to more established online marketplaces such as Amazon and eBay, with millions of UK shoppers turning to them for seemingly affordable products.
Which? said its heater research showed they needed to be better regulated.
“Cheap electric heaters are a tempting purchase for consumers struggling during the cold winter months, but our latest tests have revealed that models sold on TikTok and Temu are a serious safety risk and must be avoided at all costs,” said Sue Davies, Which?’s head of consumer protection policy.
“It’s vital that the government urgently gives greater legal responsibility to online marketplaces for unsafe products so that they are forced to take action to prevent dangerous products ending up in people’s homes.”
Which? has also highlighted the role influencers play in promoting the heaters.
TikTok Shop is interwoven into the video-sharing app, with products available on it frequently appearing in creators’ videos on the platform.
Which? identified several posts from influencers promoting fire hazard heaters in TikTok search results.
Lesley Rudd, chief executive of Electrical Safety First, urged them to take responsibility for their actions, saying they had “a moral duty” to ensure the products they recommended to followers were safe.
She also agreed current regulations were “broken”, given the rise of new online sellers.
“The way we shop has changed, possibly forever, yet it is utterly illogical that our laws have not, leaving people shopping on these online platforms grossly unprotected from dangerous electrical products,” she said.
Which? purchased and tested five portable heaters from TikTok Shop, and three from Temu. Only one was both safe for home use and legal for UK sale, according to the group.
A Temu spokesperson told the BBC “we deeply regret any concern or inconvenience caused by the safety issues” in the products identified by Which?, saying it had removed the heaters.
“The safety of our customers is our highest priority, and we have taken immediate action to address this issue,” they said.
TikTok also pointed to the action it took to keep consumers safe.
“If TikTok finds merchants or products that violate their policies, they remove them”, it said in a statement.
What can I do if I can’t afford my energy bill?
- Check your direct debit: Your monthly payment is based on your estimated energy use for the year. Your supplier can reduce your bill if your actual use is less than the estimation.
- Pay what you can: If you can’t meet your direct debit or quarterly payments, ask your supplier for an “able to pay plan” based on what you can afford.
- Claim what you are entitled to: Check you are claiming all the benefits you can. The independent website has a useful guide.