Composting organic waste is an important component of the waste management
process and the strategy to reduce waste to landfill, and as a result there has
been an increase in the number of commercial composting operations.
Microbiological activity is fundamental to the composting process,
therefore any handling of composting material is likely to make airborne
significant quantities of those micro-organisms (referred to as bioaerosols).

The British Health and Safety Executive has published a report to discuss these
dangers.

More info

AplusA-online.de - Source: Health and Safety Executive