Background: Intense and persistent exposure to indoor-air biological agents has been associated with the appearance of allergic diseases. Archives and libraries Indoor environments in tropical countries are an important reservoir of fungal propagules. Objective: To evaluate the degree of air pollution with allergenic fungi in a repository of frequentlymanipulated documents. Methods: Air sampling was performed by two methods: active (biocollector) and passive (sedimentation plate). Fungi were taxonomically identified, and spores were measured to determine their penetrability in the human respiratory tract, and its impact on episodes of allergy. Results: In terms of concentration and diversity, the local environment behaved as a fungal propagule reservoir, which showed that there is significant health risk for the staff that manipulates the documents. Some spores were shown to be able to reach the lower respiratory tract when inhaled, which increases their allergenic and pathogenic potential. Aspergillus, Cladosporium, Penicillium and Alternaria, which are referred to as highly allergenic fungi, were prevalent. Conclusion: Aerobiological studies are a valuable tool for the treatment of patients with allergy to fungi and other disorders they produce.