Does Using Corsi–Rosenthal Boxes to Mitigate COVID-19 Transmission Also Reduce Indoor Air Concentrations of PFAS and Phthalates?

The
COVID-19 pandemic brought new emphasis on indoor air quality.
However, few studies have investigated the impact of air filtration,
a COVID-mitigation approach, on indoor air concentrations of semivolatile
organic compounds (SVOCs). Using a quasi-experimental design, we quantified
the impact of a relatively low-cost “do-it-yourself”
air filter (Corsi–Rosenthal Box; CR Box) on indoor air concentrations
of 42 PFAS and 24 other SVOCs. We sampled air before (October–November
2021) and during (February–March 2022) deployment of CR Boxes
in 17 rooms located in an occupied Providence, Rhode Island office
building. We measured sound levels in rooms with CR Boxes operating
and not operating. While CR Boxes were deployed, concentrations of
seven PFAS (N-EtFOSE, N-EtFOSA, FBSA, PFBS, PFHxS, PFOS, PFNA) were
28–61% lower and concentrations of five phthalates (DMP, DEP,
DiBP, BBzP, DCHP) were 29–62% lower. Concentrations of five
PFAS and one phthalate increased 23–44% during the intervention
period, but the 95% CI of most of these estimates included the null.
Daytime sound levels increased 5.0 dB when CR Boxes were operating.
These results indicate that CR Boxes reduced exposure to several lower-volatility
phthalates and sulfonated PFAS previously reported to be found in
office building materials and products, with potentially distracting
increases in sound levels.