Does Loreal Hair Color Cause Cancer?

Yes!
But it's suppressed!

See the USC bladder cancer study,
and the Yale non-Hodgkins study.

There are preventive methods to keep
hair dye off the scalp but only gloves are
included.

There are some studies which suggest that hair dyes increase the risk of bladder cancer non Hodgkin' s lymphoma.  Some studies also suggest that only those barbers are at risk who dye hairs of the customers. The evidence which suggests that risk of cancer in the hair dye user is small and lack much scientific support.