I've often thouhgt about getting a water filter, but been put off by
not knowing what source the activated carbon is from. There's no
useful information that I've found online, including google's usenet
archive.

Anyway, in an act of boredom yesterday I emailed Brita (maker of many
water filters in the UK) and asked what they use in their's. The email
I recieved back may be of interest to UK people of this group:

"I can confirm the contents of the cartridge are as follows -

Ion exchange Resin - Sythetically manufactured , insoluable
artificial Resin.

Activated Carbon - Made from coconut shell. "

ttfn