hello Tahar,

as per your question see there are more than 200 species known or identified for Pseudomonas genus, however hardly 20 species are found pathogenic to human. another thing is genus Pseudomonas may be present as normal flora of any human being so first you get more details about pathogenic species and then go for isolation and other experimentals. wish you for success.

These bacteria are not harmful and no threats to human health have been reported so far. So it is safe to work with these bacteria.

Tahar-

All of the comments listed above are correct.  It will depend on the specific strain and how it is handled.  As long as proper handling (pre and post sterilization, gloves, safety glasses, etc.) and disposal practices (sterilization of cultures, glassware and 'bleach' on surfaces, etc. ) are used, both should be safe to use. 

I agree to Teresa that handling of the activities and processes counts too much. If you take care of the regulations for a specific procedure then no major threats are probable.