HEPA filtration intervention in classrooms may improve some students’ asthma

Abstract

Objective

The School Inner-City Asthma Intervention Study 2 (SICAS 2) tested interventions to reduce exposures in classrooms of students with asthma. The objective of this post-hoc analysis was limited to evaluating the effect of high-efficiency particulate (HEPA) filtration interventions on mold levels as quantified using the Environmental Relative Moldiness Index (ERMI) and the possible improvement in the students’ asthma, as quantified by spirometry testing.

Methods

Pre-intervention dust samples were collected at the beginning of the school year from classrooms and corresponding homes of students with asthma (n = 150). Follow-up dust samples were collected in the classrooms at the end of the HEPA or Sham intervention. For each dust sample, ERMI values and the Group 1 and Group 2 mold levels (components of the ERMI metric) were quantified. In addition, each student’s lung function was evaluated by spirometry testing, specifically the percentage predicted forced expiratory volume at 1 sec (FEV1%), before and at the end of the intervention.

Results

For those students with a higher Group 1 mold level in their pre-intervention classroom than home (n = 94), the FEV1% results for those students was significantly (p < 0.05) inversely correlated with the Group 1 level in their classrooms. After the HEPA intervention, the average Group 1 and ERMI values were significantly lowered, and the average FEV1% test results significantly increased by an average of 4.22% for students in HEPA compared to Sham classrooms.

Conclusions

HEPA intervention in classrooms reduced Group 1 and ERMI values, which corresponded to improvements in the students’ FEV1% test results.

Keywords:

• Spirometry
• mold
• ERMI
• dust
• forced expiratory volume

Acknowledgements

We would like to thank the schools and families that participated in this study.

Declaration of interest

In accordance with Taylor & Francis policy and our ethical obligation as researchers, we are reporting that Dr. Phipatanakul has consulting/advisory relationships with Genentech/Novartis, Sanofi, Regeneron, Astra Zeneca and trial support from Genentech, Novartis, Sanofi, Regeneron, Merck, Circassia Alk Abello, Lincoln Diagnostics, Monaghen, Thermo Fisher. However, Dr. Phipatanakul’s relationships with these companies have no bearing on this study. We have disclosed these interests fully to Taylor & Francis. None of the other authors have any similar relationships or potential conflicts.

Notice

The U.S. Environmental Protection Agency (EPA) through its Office of Research and Development collaborated in the research described here. Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official EPA policy. Mention of trade names or commercial products does not constitute endorsement or recommendation by the EPA for use. In addition, ATSDR does not endorse the purchase of any commercial products or services mentioned in PEHSU publications.

Data availability statement

The data that support the findings of this study are available from the corresponding author, [SJV or WP], upon reasonable request.

Additional information

Funding

This work was supported by the National Institutes of Health; grant number (awardee); K23 AI123517 (Permaul), K23 AI143962 (Bartnikas), K23 AI104780 (Sheehan), R01 ES030100 (Gaffin), R01 AI144119 (Lai), R01 AI073964, R01 AI073964-02S1, K24 AI106822, U10 HL098102, U01 AI110397, R01 HL137192, U19AR06952 (Phipatanakul). This work was also supported by the cooperative agreement award number 1 NU61TS000296-01–00 from the Agency for Toxic Substances and Disease Registry (ATSDR) (Hauptman). The U.S. Environmental Protection Agency (EPA) supports the Pediatric Environmental Health Specialty Unit (PEHSU) by providing partial funding to ATSDR under Inter-Agency Agreement number DW-75–95877701.