I don't know if it will help but I just posted a Q about RO systems in the Lounge. I'll be checking this thread too if you don't mind
There are countertop RO systems available. Not sure about BPA free ones. I think Brita actually *is* BPA free though? However, there is the new research out stating that other plastics also leech estrogen mimickers (sigh) so I'm not sure how helpful that is.
Some of the RO systems apparently have BPA in their holding tanks, but there are "tankless" models and I've found a few that advertise being BPA free. I haven't gotten to research it enough yet, but since our posts are kind of related I thought I'd mention that.
Mama to DS-2004
DD-2006
and a new addition-ds born march 2010