Air pollution
LA air toxics, especially PAHs, track preterm birth
Open access · cc by · source: Europe PMC
In Los Angeles, entire-pregnancy PAHs associated with ~30% higher preterm-birth odds; ammonium nitrate PM2.5 and several traffic markers also raised odds.
Study at a glance
- Design
- Case-control — Population-based case-control of LA preterm birth near MATES monitors with traffic toxics
- N
- N=241415 · 241,415 births after exclusions from 276,891 birth records; analyses often restricted nearer monitors
- Population
- Births in Los Angeles County near MATES air-toxics monitors
- Outcome
- Preterm birth odds related to PAHs, traffic markers, and source-apportioned PM2.5
Structured fields used in claim comparison tables when every cited study has a complete layer.
Key findings
Preterm prevalence 9.2%. Total PAHs and several PAH species ~30% odds increases (benzo(a)pyrene 13%) but small PAH samples. IQR increases in ammonium nitrate PM2.5 and 9–13% odds rises for benzene, diesel/EC/OC, and biomass-burning PM2.5.
Methodology
Population-based case-control of births near MATES monitors used three exposure sources (stations, LUR, source-apportioned PM) in conditional logistic models of preterm birth.
Limitations
PAHs were measured at only two stations for shorter periods; residual SES confounding and spatial monitor coverage limit causal claims for a single toxin.
How this study connects
Role on claims
Each row is a claim on a concept or method page where this paper supports, challenges, or qualifies the statement. Roles are hand-checked — not a model guess.
This library holds 9 empirical papers on air pollution with measured outcomes rather than reviews.
Evidence for the claim as stated.
In Los Angeles, entire-pregnancy PAHs associated with ~30% higher preterm-birth odds; ammonium nitrate PM2.5 and several traffic markers also raised odds.
Evidence for the claim as stated.
A Los Angeles case-control of births near MATES monitors (preterm prevalence 9.2%) used stations, land-use regression and source-apportioned PM in conditional logistic models. Total PAHs and several PAH species showed ~30% odds increases (benzo(a)pyrene 13%), but PAH samples were small and limited to two stations. IQR increases in ammonium nitrate PM₂.₅ and 9–13% odds rises appeared for benzene, diesel/EC/OC and biomass-burning PM₂.₅.
Evidence for the claim as stated.
Two preterm-birth analyses both sit near a 9% outcome and do not report the same contrast. Los Angeles finds ~30% PAH odds increases (benzo(a)pyrene 13%) plus 9–13% for several PM sources, with PAH data from only two stations. PROTECT reports RR 1.014 per IQR of pregnancy PM₂.₅ at a mean of 6.8 μg/m³. Odds ratios and risk ratios are not interchangeable, and the exposure products (PAH stations versus municipality monitors) are not the same assignment.
Evidence for the claim as stated.
Los Angeles preterm-birth models drew on MATES monitors, LUR and source-apportioned PM (preterm prevalence 9.2%). Total PAHs and several species showed ~30% odds increases (benzo(a)pyrene 13%) but PAH samples were small and limited to two stations for shorter periods. IQR increases in ammonium nitrate PM₂.₅ and 9–13% odds rises appeared for benzene, diesel/EC/OC and biomass-burning PM₂.₅.
Evidence for the claim as stated.
LUR can be one of several exposure assignments in the same case-control study. Los Angeles preterm-birth analyses used monitors, LUR, and source-apportioned PM: preterm prevalence 9.2%, with ~30% odds increases for total PAHs (benzo(a)pyrene 13%) but small PAH samples, plus IQR associations for ammonium nitrate PM₂.₅ and 9–13% odds rises for benzene, diesel/EC/OC and biomass-burning PM₂.₅.
Evidence for the claim as stated.
These papers do not agree on which traffic-related layer carries the signal. Rome’s analysis is built on NO₂ LUR as the exposure; the neurologic cohort finds air pollution associated with some diagnoses and not others, with greenness attenuating and noise mostly null; the LA preterm paper’s PAH signal is limited by two stations and shorter sampling. Treating 'LUR showed pollution is bad' as a single result hides those splits.
Evidence for the claim as stated.
Open questions
Tensions this paper is part of
From concept pages' “where studies disagree.” Disagreement means the same question; scope means different assays, populations, or outcomes.
Two preterm-birth analyses both sit near a 9% outcome and do not report the same contrast. Los Angeles finds ~30% PAH odds increases (benzo(a)pyrene 13%) plus 9–13% for several PM sources, with PAH data from only two stations. PROTECT reports RR 1.014 per IQR of pregnancy PM₂.₅ at a mean of 6.8 μg/m³. Odds ratios and risk ratios are not interchangeable, and the exposure products (PAH stations versus municipality monitors) are not the same assignment.
These papers do not agree on which traffic-related layer carries the signal. Rome’s analysis is built on NO₂ LUR as the exposure; the neurologic cohort finds air pollution associated with some diagnoses and not others, with greenness attenuating and noise mostly null; the LA preterm paper’s PAH signal is limited by two stations and shorter sampling. Treating 'LUR showed pollution is bad' as a single result hides those splits.
Related papers in this topic
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