Well i don't really like to translate it, because mine english isn's very well, so read and following text is at your own risk:

There has been a modifed manual been released for the MSR miniworks filters and it's replacement elements with model number 35422 and 356210.

under certain situation bacteria can go through the filter, which may cause the user to get ill. To prevent this Cascade Designs recommends you to boil the filter every 4th day of use, according to the direction on the (modified) manual.

For more information, you can contact: C.J. Agencies, Baarn. With telephone number (031)35 542 42 00.



The text from the PDF file.

importent safety warning voor dutch consumers
Modified user manual for the MSR miniworks


MSR miniworks portable microfilter and replacement element.
Modelnumber 35422 and 356210.

Risk : recent tests has shown that under certain situations, bacteria can grow on the ceramic filter and after four days of use or inproper stporage bacteria can come through the filter, which may cause illness to the user.

Meassures to prevent this: Cascade Designs recommends you to boil the filter, as shown in the manual, every 4th day of use We have made a modified section of the manual for the Dutch consumers (see underneed), with instuction for storage and cleaning of the MSR miniworks filter.

The add on bit of the modified section of the manual:

Boiling out the cermaic element
Boil the ceramic element out after foru days of continues use. Also boil it out after long term storage. Especially when it has been stored damp.

1. Remove the Cermamic element for the housing.
2. Remove the rubber ring for the botom of the element.
3. place the Cermamic element element in a pan with water on room temperature. the pan should be large enough to submurge the intire Cermamic element and able to boil it, without boiling over.
4. Heat the pan to boil the water and let the element boil through for 5 minutes.
5. Cut the power/gas off and let the water cool, before removing the element.
6. Let the Cermamic element air dry thoroughly. *this stap can be let out if the element is used again. Boiling it through is needed before storage.
7. Wash all other parts of the filter with hot water and detergent and dry properly.
8. Put the filter back together.
importent don't forget the replace the rubber ring on the botom.





When using the MSR miniworks follow the supplied manual and the instructions on this add-on sheeth. Cascacade Designs regrets for the uncomfort. If you have any questions please contact:

Contact Information: C.J. Agencies, Baarn (031)35 542 42 00.

PC2K,
Cool, Thanks for translating you did very well; I wish I could speak dutch so you are one up on me.

I would not be too worried. When I worked at a local REI we would get customers who would return a filter/purifier with all kinds of mold in it. They obviously did not dry out the cartridge after use which is necessary.
Boiling the MSR filter will work but air drying will kill the bacteria too. I would not worry about the bacteria while in the field for a short to meduim-long trips. I bet it would be fine plus in most wilderness it is not bacteria as much as protozoans you need to worry about.