<<Disclaimer: Verify this information before applying it to your situation.>>

We are on vacation in London and I just spoke with Customer Service for
McDonald's in the UK.  Like McDonald's in America and Canada, they use the
same oil vats to fry French Fries and Hash Brown potatoes.  However,
unlike America and Canada, the Hash Browns here contain wheat starch.
This would appear to contaminate the oil, and therefore contaminate the
French Fries.

If any local Coeliac Society members have more detailed information,
please post it to the List.

Interesting historical note:  The Customer Service agent told me that
McDonald's used to import their Hash Browns from America, and when they
did, they contained corn starch instead of wheat starch. They have a
policy of using local ingredients whenever possible and were recently able
to change to a UK supplier of Hash Browns who used wheat instead of corn.

Bill Elkus