bioeffluents at high CO2 significantly raised salivary α-amylase, a stress marker
Exact: 3000 ppm
Bioeffluent exposure at 3000 ppm CO2 significantly increased salivary α-amylase compared with pre-exposure levels
Salivary α-amylase is a well-established biomarker of autonomic arousal and psychological stress. Its significant increase under bioeffluent exposure (restricted ventilation, 3000 ppm CO2) compared to pre-exposure baseline reinforces the interpretation that bioeffluents drive a stress/arousal response beyond what CO2 alone would cause.
Exposure to bioeffluents, when metabolically generated CO2 was at 3000 ppm, significantly increased diastolic blood pressure and salivary α-amylase level compared with pre-exposure levels, and reduced the performance of a cue-utilization test: These effects may suggest higher arousal/stress.
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2260 ppm
poor ventilation pushed CO₂ to more than four times the high-ventilation level
Low ventilation caused CO2 to rise to 2260 ppm
H. Maula et al., 2017, Indoor Air
540 ppm
high ventilation kept indoor CO₂ near outdoor-equivalent levels
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