UK shoppers have been warned of the risks of buying electrical goods from third-party online sellers on sites such as Amazon, eBay and Wish.

Electrical Safety First, a consumer safety charity, bought a selection of items, including hair straighteners, phone chargers, travel adaptors and laser hair removers from the online retailers.

The products, which were selected based on their potential risk, nearly all failed tests against UK standards. Only one of the 15 items bought passed every electrical safety requirement. Some simply lacked compliance with required markings on the outside of plugs, but other failures were more severe:

A phone charger purchased from Wish – visually identical to an official Apple USB charger – came fitted with no protective devices to prevent “catastrophic failure” in the event of damage or surges. In testing, the charger ruptured internally, which can lead to an explosion.

A hairdryer, also purchased from Wish, caught fire during a safety test involving obstructions to the airflow. The product emitted flames and its plastic enclosure melted.

A laser hair remover, bought on eBay, had live parts accessible, risking electric shocks to the user.

A modelling comb, bought from Amazon Marketplace, was fitted with a plug that broke UK safety regulations and risked potential fire, according to the charity.

“The results of our tests are extremely worrying for those who buy electrical products from online marketplaces,” said Martin Allen, the charity’s technical director. “No product that fails our tests should be being sold, and it’s very clear that the lack of regulation of online marketplaces – from government or from the sites themselves – is allowing those who sell dangerous goods to make a profit at the expense of consumer safety.”

A damaged hairdryer after a prevention of air flow test. Photograph: Electrical Safety First

While Wish, Amazon and eBay are popular sites with enormous UK revenues, all three allow third parties to sell goods with barely any oversight. In 2018 a Guardian investigation found that Amazon retailers were selling knockoff AirPods, counterfeit lipgloss, and secondhand chargers labelled as new.

Consumer rights group Which? said the research was alarming. “The next government must make marketplaces legally responsible for preventing unsafe products from being sold on their sites, establish clearer requirements for taking down dangerous products and ensure better enforcement is in place to keep consumers safe,” said its director of advocacy, Caroline Normand.

A USB charger failing catastrophically. Photograph: Electrical Safety First

In a statement, Amazon said: “Safety is a top priority at Amazon. We require all products offered in our store to comply with applicable laws and regulations and have developed industry-leading tools to prevent unsafe or non-compliant products from being listed in our stores. The products have been removed.”

An eBay spokesperson said: “We proactively enforce our product safety policy using block filter algorithms to prevent unsafe products from being listed. In addition, our security team continuously patrols our marketplaces and will remove items and take appropriate action against sellers who breach our policies … the managed listings have been removed and the sellers notified to reach out to buyers with the alert and their return policy.”

Wish said it had removed the items “as soon as Electrical Safety First made us aware”.