In Reply

Letter to the Editor Indoor Mold Important Considerations for Medical Advice to Patients by Dr. rer. nat. Julia Hurraß, Prof. Dr. med. Dennis Nowak, Dr. med. Birger Heinzow, Dr. med. Marcus Joest, Dr. med. Jannik Stemler, and Prof. Dr. med. Gerhard A. Wiesmüller in issue 8/2024

We thank Johanning et al. for their contribution to the discussion, which allows us to expand on possible toxic effects in indoor moisture/mold damage.

In pour article (1) we refer readers to the AWMF guideline on the medical clinical diagnosis of indoor mold exposure (“Medizinisch klinische Diagnostik bei Schimmelpilzexposition in Innenräumen—update 2023”) (2), which in the meantime has also become available in English [3]) and which addresses in detail possible toxic effects in a setting of damage owing to indoor dampness/mold damage on the basis of extensive cited literature, including the mentioned publications by Johanning et al.

No definite/certain knowledge exists to date as regards airborne intoxication with components of the bioaerosol. Clarification is needed of whether concentrations of bioaerosol components in indoor air are of system-toxic relevance (2, 3). According to what is currently known this does not seem to be the case, as a rule. In individual cases of extreme moisture damage with a massive mold burden and therefore very high exposure, as described by Johanning et al. (4) in workers in renovation/restoration companies and volunteers in clean-up efforts after natural disasters, among others, the suggestion is that symptoms of poisoning may occur (2, 3). In Germany, however, workers at high exposure owing to their jobs are obliged by the statutory accident insurance to protect themselves sufficiently. The same is the case for volunteers.

It is unlikely that portal of entry effects, such as cytotoxic, inflammatory effects in the respiratory tract, can be causally explained exclusively with mycotoxins, since exposures in damp and moldy rooms is always a complex exposure to the most different irritative, cytotoxic, and immunogenic components of the bioaerosol (2, 3). Hypothetical immunomodulatory effects of mycotoxins need to be examined (2, 3). Monitoring of inhaled mycotoxin exposure is currently not possible with sufficient certainty (2, 3).

Our article (1) therefore does not underestimate toxic events and informs medical professionals objectively and comprehensively about the health risks, to the benefit of patients.

DOI: 10.3238/arztebl.m2024.0123

On behalf of the authors

Prof. Dr. med. Gerhard A. Wiesmüller

HYGIUM – Zentrum für Hygiene und Umweltmedizin GmbH
(zuvor: ZfMK – Zentrum für Umwelt, Hygiene und Mykologie Köln GmbH)

Conflict of interest statement

GAW received honoraria for expert appraisals of case constellations involving mold problems. He participated in the preparation of the 2023 update of the AWMF guideline on the medical clinical diagnosis of indoor mold exposure (“Medizinisch klinische Diagnostik bei Schimmelpilzexposition in Innenräumen” (AWMF Register No. 161/001).

References

1. Hurraß J, Nowak D, Heinzow B, Joest M, Stemler J, Wiesmüller GA: Indoor mold—important considerations for medical advice to patients. Dtsch Arztebl Int 2024; 121: 265–71

2. Hurraß J, Heinzow B, Walser-Reichenbach S, et al.: AWMF-Schimmelpilz-Leitlinie „Medizinisch klinische Diagnostik bei Schimmelpilzexposition in Innenräumen“ – Update 2023. AWMF-Register-Nr. 161/001; www.register.awmf.org/de/leitlinien/detail/161-001 ; (last accessed on 2 June 2024)

3. Hurraß J, Heinzow B, Walser-Reichenbach S, et al.: AWMF mold guideline “Medical clinical diagnostics for indoor mold exposure”—Update 2023 AWMF Register No. 161/001. Allergol Select 2024; 8: 90–198

4. Johanning E, Auger P, Morey PR, Yang CS, Olmsted E: Review of health hazards and prevention measures for response and recovery workers and volunteers after natural disasters, flooding, and water damage: mold and dampness. Environ Health Prev Med 2014; 19: 93–9