Pressure is being put on the Scottish Executive to enforce the licensing and inspection of all sunbed parlours.
More than 20% of Scots regularly use a sunbed
The Royal Environmental Health Institute of Scotland (REHIS) said unlicensed tanning salons posed a real threat to public safety.
There are more sunbed parlours in Scotland per head of population than in any other part of the UK, according to the REHIS.
It warned that over-exposure to the ultra violet radiation emitted from sunbeds can lead to skin cancer, eye damage and premature ageing.
Some local authorities have introduced their own schemes to licence sunbed salons using public entertainment powers under the Civic Government (Scotland) Act.
However, this process can be lengthy and time-consuming and controls differ across the country.
The REHIS called for the executive to introduce Scotland-wide legislation.
It said its health staff had found underage children using sunbeds despite the increased risk of developing skin cancer.
In some situations there is no monitoring of the number of sessions taken by clients and poor management of UV lamp strengths.
John Sleith, of the REHIS Council, said more than 20% of Scots regularly use a
sunbed and warned that the growth of unlicensed parlours posed a "real threat"
to public safety.
He called on Scottish Health Minister Malcolm Chisholm to address the problems
as a priority.
"Some of the safety lapses encountered by our members are extremely worrying,
and the country needs legislation to protect those people who are determined to
use these machines," Mr Sleith added.
"Damage cause by ultraviolet light may not make itself evident for years, but
it can be deadly, and we have to ensure controls are in place.
"This is a growing industry, but many tanning centres are not supervised, or
are staffed by people who are not properly trained."