Two more children's sand kits have been removed from sale after testing found they contained asbestos.
One was marketed as a Montessori sand art tray, and was being sold on Amazon Marketplace and TikTok Shop.
A second sand art tray was bought from TikTok Shop and was also found to be for sale from three individual sellers on Amazon Marketplace.
Researchers also discovered tremolite asbestos in the GL Style Sand Bottle Art Heart or Stars set, bought from Asda and carrying the brand name RMS International Limited.
But they also found what appeared to be the same kit for sale on eBay from three private sellers.
The items are among many children's toys which are being recalled from shelves because of asbestos contamination.
More than 39 recall notices have been issued since November relating to asbestos-contaminated sand products.
The first sand tray is designed for hands-on learning by encouraging children to draw in the sand using pencils or with their fingers.
Testing by Which? showed the sand contained the banned substance tremolite asbestos, a harmful naturally occurring mineral that can cause severe lung diseases if inhaled, even at low exposure levels.
The second tray stayed on sale on TikTok Shop and Amazon Marketplace until May, despite the same product being subject to a recall by the Office for Product Safety and Standards (OPSS) in March because of asbestos contamination.
The OPSS has now updated the original recall notice to include both platforms.
The issue of asbestos-contaminated sand products has also led to the closure of schools and parks, most recently in North East England.
It is believed the affected toys contain sand sourced from specific quarries in China, where naturally occurring asbestos is present.
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Sue Davies, from Which?, said: "It is outrageous that online marketplaces are selling products which may expose children to asbestos, especially when some of these products had already been recalled by the OPSS."
She added: "The longer the government delays taking action, the greater the risk that more dangerous products will reach consumers."
An Amazon spokesman said: "Customer safety is our top priority and we are taking this issue very seriously.
"We are in the process of removing all products in this category across our store while we investigate further, and as a result the highlighted items have been removed."
Asda said it began a full product recall as soon as it was made aware that the product had failed testing.
The company advised customers who had bought the product to stop using it immediately and return it to their nearest store for a full refund.
A spokeswoman for eBay said: "We swiftly removed the items identified by Which? and are conducting further sweeps to identify similar listings."
TikTok said the product identified during the investigation had already been removed from TikTok Shop.
(c) Sky News 2026: Two more children's sand kits withdrawn from sale over asbestos content
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