* New rules may need 54 mln animals, scientists say
* Call for urgent review of testing requirements
LONDON, Aug 26 (Reuters) - Far-reaching European safety rules on tens of thousands of chemicals used in everything from car seats to face cream will lead to a surge in animal testing and should be urgently reviewed, scientists said on Wednesday.
The regulations may need 54 million research animals and cost 9.5 billion euros ($13.6 billion) to implement over the next 10 years -- 20 times the number of animals and six times the cost previously anticipated, they reported in the journal Nature.
The European Union's REACH (Registration, Evaluation and Authorisation of Chemicals) legislation came into effect two years ago, requiring companies to assess the toxicity of chemicals that date from before the era of mandatory testing.
A new analysis by researchers at the Johns Hopkins Bloomberg School of Public Health found the number of chemicals pre-registered for REACH by industry had vastly exceeded expectations, pointing to a vast volume of testing.
"As a toxicologist, I support the aims of REACH -- it is the biggest investment into consumer safety ever," said study author Thomas Hartung.
"However, I am concerned that we have underestimated the scale of the challenge. Investment into developing alternative research methods to meet REACH goals is urgently needed."
Hartung and co-author Constanza Rovida said up to 101,000 chemicals could be covered by REACH, three times earlier estimates.
The REACH legislation has already proved controversial with some manufacturers, fearful it may push up costs, and with animal rights groups, who wrote to European regulators earlier this month calling for curbs on unnecessary animal tests.
(Reporting by Ben Hirschler; editing by John Stonestreet)