A common ingredient in beauty products can increase the users' chances of suffering from "superbug" infections, including MRSA.

Scientists have discovered repeated exposure to low doses of tea tree oil could endanger people.

Experts from the University of Ulster revealed exposure to low doses of the oil-made pathogens such as MRSA, e-coli and salmonella, more resistant to antibiotics, and capable of causing more serious infections.

Tea tree oil is commonly used in many products, including shampoos, body lotions and toiletries, but there is no legislation requiring manufacturers to state the concentration of the oil in any of the products.

The university's Professor David McDowell said the failure of manufacturers to state the concentration of tea tree oil in products increased the risks people would use low concentrations of the product, fail to kill bacteria and increase their resistance to antibiotics.