The number of cases of the most serious form of skin cancer has more than doubled in Northern Ireland during the past 20 years, it has been revealed.
Complacency about the risks, the increased popularity of foreign holidays and the use of sunbeds were blamed for the increase, Gerry McElwee from the Cancer Focus charity said.
He helped launch a new Care in the Sun website and revealed around 3,300 people develop skin cancer every year – around a quarter of all cancer cases.
"We have very light skin colours but people rate their skin much darker than it actually is, believing they never burn but tan," Mr McElwee said.
"In actual fact those groups are very rare in our society, there is a perception that 'it is not a problem for me' for a lot of people and some people are not aware of the dangers and some may not be aware of the link between ultraviolet and sunburn and the potential for skin cancer."
He added there may be a time lag between people's exposure to rays in the 1960s, '70s and '80s creating cancers now.
Dr Miriam McCarthy, consultant in public health at the Public Health Agency, said the number of cases of malignant melanoma, the most serious form of skin cancer, had more than doubled, highlighting the need for action.
In 1993 there were 58 cases of malignant melanoma but by 2011 that had risen to 126.
People have been warned to avoid prolonged exposure when sun in strongest and cover up with a t-shirt, sunglasses and hat while wearing sunscreen.
Health Minister Edwin Poots said: "Substantial progress has been made in the area of skin cancer prevention. However, we will continue to see rising rates, due to the amount of sun exposure people have already had.
"That is why I would encourage everyone to be aware of changes in their skin and to report any changes to their GP. Early detection can save lives."
A good way to tell the difference between a normal mole and a melanoma is to use the ABCDE checklist:
* A stands for asymmetrical – melanomas have two very different halves and are an irregular shape.
* B stands for border – unlike a normal mole, melanomas have a notched or ragged border.
* C stands for colours – melanomas will be a mix of two or more colours.
* D stands for diameter – unlike most moles, melanomas are larger than 6mm (1/4 inch) in diameter.
* E stands for enlargement or evolution – a mole that changes characteristics and size over time is likely to be a melanoma.