Finding F-1235

“However, the formaldehyde concentration in the chamber increased from 0.5 ppbv (0.6 μg m−3) the day before the tree was placed in the chamber to 3.1 ppbv (3.9 μg m−3) when the tree was present prior to the ozone being injected on Day 2.”

Poppendieck et al. Jingle bells, what are those smells? Indoor VOC emissions from a live Christmas tree (2024). Indoor environments. Page 9. CKB 6007

Structure

Factor: Formaldehyde (CH₂O)
Method: Emission test chamber method
Setting: test chamber, US
Study design: chamber study at the National Institute of Standards and Technology: a freshly cut Douglas fir stood for seventeen days in an environmentally controlled chamber and the volatile organic compounds it emitted were measured continuously with a proton transfer reaction mass spectrometer, with ozone injected on several of the days to observe the indoor chemistry it starts (class 4)
Effect: mean
Caveat: the study notes that the researcher setting the tree in its stand could have contributed to the increase

A Finding records what one published document states, verbatim and with its page. It is not a conclusion of Coridum; see the Claims that build on it.