Risk of contamination under control (Infastaub)

What is the benefit of a secure filtration of lung-current, harmful or toxic dust and particulate matter if contamination dangers for person and nature lurk with the dust disposal and the change of the filter media?

https://www.intensiv-filter.com/fileadmin/user_upload/presse/files/20111006_CAV_Kontaminationsgefahr_gebannt1.pdf