You could place part of the mould into a cut in a piece of citrus fruit to continue its growth. Citrus can also host P. italicum, the below website is one mentioning how to differentiate between them.
http://www.pestnet.org/fact_sheets/citrus_storage_moulds_197.html
Hazards.
Aspergillosis: (fungal spores growing in the lungs) which is uncommon.
Asthma: penicillium spores have been associated with increased chance of onset of asthma, and problems with breathing in people with asthma.
There may be other hazards.
I just cite one paper below, but a search using terms of penicillium and asthma shows lots more.
"Household airborne Penicillium associated with peak expiratory flow variability in asthmatic children"
published in :
Annals of allergy, asthma & immunology : official publication of the American College of Allergy, Asthma, & Immunology
by:
Kemp W. Bundy, MD, MBA, Janneane F. Gent, PhD, [...], and Brian P. Leaderer, PhD
doi: 10.1016/S1081-1206(10)60139-1