Jewellery advertised as sterling silver on Amazon, eBay, Temu, Etsy and OnBuy was found to contain toxic chemicals, following a BBC investigation.

Some 25 items were examined by experts for BBC Watchdog on The One Show. Laboratory analysis found eight contained illegal levels of cadmium – a chemical that can cause cancer. Only two items could be classified as sterling silver.

Amazon, eBay, Temu and OnBuy said misleading listings were prohibited and that it had removed the jewellery identified by Watchdog. Etsy did not respond.

Meranda, 34, bought a necklace advertised on Etsy as handmade sterling silver but says after a few days of wearing it her “neck started getting really irritated”.

“I remember looking at it as I took it off and thinking the colour on this doesn’t look right.”

Meranda’s necklace and the 25 other pieces purchased by Watchdog were analysed by the Sheffield Assay Office.

According to preliminary testing, Meranda’s necklace was found to contain nickel – another toxic chemical that can cause skin irritation. There are strict legal limits on how much nickel jewellery can contain.

Meranda’s necklace was found to have traces of nickel but in one part of the chain the concentration was as high as 11%.

Sterling silver jewellery does not typically contain nickel but it is found in some cheaper items.

Of the 25 pieces of jewellery bought by Watchdog – which included items like a bracelet for £1.55 and earrings for £1.99 – eight items contained levels of cadmium over the legal limit of 0.01%.

Some had up to 10% cadmium. “[That] is absolutely massive, relative to the limits we’re adhering to,” says Sophie Langley, who led the analysis.

Morning Live’s consumer expert Rebecca Wilcox shares her tips on how to make sure you’re buying the real deal:

Cadmium is a carcinogen associated particularly with lung cancer, says Rob Chilcott, a retired professor of toxicology.

It poses a risk to humans if it is inhaled or ingested. For example, an earring falling into food that you then eat.

“If you put something containing cadmium in your mouth, or indeed if you swallow it, that is really bad news,” he says.

Of the eight items found to have breached cadmium limits: three were purchased from Amazon, three from Temu and one from each of OnBuy and Etsy.

Meranda says she had no reason to suspect there was anything wrong with her necklace when she first received it.

“It was very shiny. It looked legit,” she says. “I did not think it wasn’t sterling silver.”

It was hallmarked with the number 925. Genuine sterling silver must contain at least 92.5% silver.

However testing revealed part of her necklace contained only 8.9% silver.

Selling fake sterling silver is a breach of the Hallmarking Act and carries the risk of fines or imprisonment, says Langley.

Temu told the BBC it had arranged testing of similar products to identify potential risks.

Amazon and eBay said customers with any concerns should contact them for support. Amazon has since issued recall notices for the products Watchdog identified as being unsafe.

OnBuy told us it had offered affected customers refunds and initiated a recall of the product our analysis identified as containing cadmium. Etsy did not respond.

Meranda contacted the Etsy seller about the £15 necklace that had irritated her neck. After speaking to Watchdog, she received a full refund.

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