Ambient formaldehyde and mortality: A time series analysis in China

Area of Science:

• Environmental Health Sciences
• Epidemiology
• Toxicology

Background:

• The health effects of low-level ambient formaldehyde exposure have been historically underestimated.
• Formaldehyde is a common air pollutant with potential adverse health impacts.
• Understanding the association between formaldehyde and mortality is crucial for public health policy.

Purpose of the Study:

• To investigate the association between ambient formaldehyde concentrations and daily mortality.
• To analyze mortality risks for nonaccidental, circulatory, and respiratory diseases.
• To estimate a concentration-response curve and identify potential threshold effects.

Main Methods:

• A two-stage time series analysis was employed.
• Data included over 5.3 million deaths across 275 Chinese counties from 2013 to 2018.
• Confounders such as meteorological factors, other air pollutants, time trends, and day-of-week effects were controlled.

Main Results:

• A 1 part per billion (ppb) increase in daily formaldehyde concentration was associated with a 0.36% increase in nonaccidental mortality.
• Associated increases were also observed for circulatory (0.36%) and respiratory (0.41%) mortality.
• A potential threshold concentration of approximately 5 ppb was identified for significant impacts on nonaccidental and circulatory diseases.

Conclusions:

• Ambient formaldehyde exposure poses a potential threat to public health.
• Further research is warranted to support pollution regulation and health protection measures.
• The findings highlight the need to consider formaldehyde in air quality management strategies.