I know it's confusing , but there is a lot of confusion and quite a distinct difference between filtration and purification!
There's a British company that sells portable purification systems. These clear the usual bacteria , parasites and viruses but the reason I chose this system is in that it excels in removing pesticides, chemicals , and trace metals!
They also sell an adapter, where you just stick it on your tap, camelpack or gravity filter...
Purified water on tap! 😉
http://www.drinksafe-systems.co.uk/products.php
Take your time to read the technology page as it explains the difference between the purification products and the filter ones.
They also sell filters , so just check all the info before purchasing.
I have no deal with them , nor do I work for them ... I'm just a happy customer!
They were very helpful before me purchasing my systems , and all my e-mails were responded swiftly!
Hope this helps ..
Ps- there's also the famous berkey filters with different candle attachments, each with different functions, sure they must do a metals one... they even do the fluoride candle...but not so portable.