Failing sterilization - there certainly are viable fungal elements in tea - and virtually all food materials. Of course, obviously contaminated tea should be discarded.
Şeyda Bostancı I would not worry about mold spores in tea treated by hot water, but they can produce some toxins before it. As I know this is a serious problem for tea, coffee, and cacao production because of longer transport routes around Africa. If Phil Geis can offer some solution for better sterilization of these products it may help.
Thanks Alex - I'd not sterilize. Methods av will screw up flavor components and, as with ither food items, are overkill. The material would be immediately recontaminated unless sterilized in finished packaging and mycotoxins would not be eliminated. Think control of conditions, esp. moisture/Aw, from harvest to packaging are sufficient.
Please relate the report of human infected by mold contamination in tea. As a clinical mycologist and microbiologist i know of no such report and doubt any real risk.