Why, you won't make water from the tap, taste better. And bottled water is pure enough.

They only contain activated charcoal, so go and buy some for a BBQ, crush it, pour water over it, funnel the run of into a coffee filter, and collect what comes off.

Get them shipped from abroad, or get them from Dubai, or try Spinneys (they sell them in a couple in Dubai). or go to www.brita.net and ask them.