PM2.5 and ozone trim North Carolina birth weights
Among 457,642 NC births, pregnancy PM2.5 and ozone were linked to slightly lower birth weight and higher SGA odds, while race/SES gaps were much larger.
Source
Assessing the impact of race, social factors and air pollution on birth outcomes: a population-based study
Study at a glance
- Design
- Cohort — NC birth records linked to census-tract PM2.5 and ozone with mixed models
- N
- N=457642 · 457,642 births after exclusions
- Population
- North Carolina births linked to neighborhood air pollution
- Outcome
- Birth weight, LBW, SGA, and preterm birth related to PM2.5/ozone and social factors
Structured fields used in claim comparison tables when every cited study has a complete layer.
What they did
Authors linked NC birth records to census-tract fused PM2.5 and ozone surfaces and fit mixed models of birth weight, LBW, SGA, and preterm birth with race, education, and neighborhood income.
What they found
An IQR rise in pregnancy PM2.5 cut birth weight 3.1 g and raised SGA odds (OR 1.03). An IQR of ozone cut 7.4 g and raised SGA (OR 1.04) and LBW (OR 1.06). Non-Hispanic Black infants weighed 187.5 g less than White infants (LBW OR 2.13). Pollution means were similar across race/SES.
The limits
What it doesn't show
Fused outdoor concentrations ignore indoor time and activity. Pollution effects are tiny versus racial disparities and are not causal at the individual level.
Key terms
- SGA
- Small for gestational age: birth weight below the 10th percentile for gestational age.
- LBW
- Low birth weight: under 2500 g.
- PTB
- Preterm birth: before 37 weeks.
- IQR exposure contrast
- The interquartile range of pregnancy-average PM2.5 or ozone used as the dose increment.
- Downscaling fusion model
- A Bayesian space-time model that predicts daily PM2.5 and ozone at census tracts.
Flashcards
Research intelligence for this paper
See its role on concept claims, tensions it is part of, placement history, and related discoveries.
Quiz yourself
IQR pregnancy PM2.5 reduced birth weight by about:
Common questions
Did minorities breathe much dirtier air in this dataset?
Mean PM2.5 and ozone were relatively consistent across race and SES.
Which outcome was most sensitive to pollution?
SGA for both pollutants; ozone also LBW; neither strongly predicted preterm birth.
Are pollution effects larger than racial gaps?
No. Black–White birth-weight gaps (~188 g) dwarf IQR pollution effects (3–7 g).
What exposure misclassification remains?
No personal monitors, indoor sources, or daily activity patterns.
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