Make-up lovers are being tricked into buying fake cosmetics that can cause chemical burns, skin rashes and internal damage.
Counterfeit Mac, Chanel and Benefit products have been found advertised by rogue traders in Cheshire, Lincolnshire and Nottingham.
A new report is warning that copycat make-up items sold in some areas contain mercury that can have a toxic effect on skin and eyes.
Exposure to mercury can be detrimental to people's health, as it can have toxic effects on the nervous system, digestive and immune systems, lungs, and kidneys.
According to the NHS, at very high levels, lead poisoning can result in hallucinations , seizures , coma and even death.
After the shocking results were laid bare by ITV, the Local Government Association is warning that, as well as defrauding consumers and legitimate businesses, these products can pose serious health risks, including chemical burns and skin rashes.
Counterfeit cosmetic investigations are currently being carried out by several councils across England.
Councillor Simon Blackburn said:'People should always do their research and take a pragmatic approach when they are buying make-up and cosmetics.
'Check the reviews of online sellers, and bear in mind that if something is really cheap, it's likely to be fake and could potentially be harmful.
'Anyone who has purchased make up that they think is dangerous should stop using it immediately and report it to their local Trading Standards team.
'It is vital that people report any concerns, so that councils can take action to prevent anyone being harmed.'