# Occupational polycyclic aromatic hydrocarbons (PAHs) exposure is associated with accelerated aging trajectories in Chinese coke oven workers

## TL;DR

Long-term exposure to PAHs in Chinese coke oven workers is linked to faster biological aging and higher odds of rapid aging trajectories.

## Contribution

This study identifies specific PAH metabolites associated with accelerated aging in an occupational cohort using trajectory modeling.

## Key findings

- Higher urinary Σ-OHPAHs, 1-OHPyr, and 2-OHPhe levels correlate with increased aging acceleration (KDM-Accel).
- Workers with the highest PAH exposure had 61.2% higher odds of rapid aging trajectories.
- Dose-response relationships were observed between PAH metabolite levels and aging acceleration.

## Abstract

Long-term effects of occupational polycyclic aromatic hydrocarbons (PAHs) on biological aging are unclear. A prospective cohort study was conducted from 2019 to 2023, involving 610 coke oven workers and 454 control workers from a water treatment plant. Biological age was calculated using the Klemera and Doubal method (KDM-BA) based on 12 clinical biomarkers, and aging acceleration (KDM-Accel) was derived. Group-based trajectory modeling (GBTM) was employed to identify distinct aging trajectories over five time points. The associations between eleven urinary mono-hydroxylated PAH metabolites (measured via HPLC-MS) and both KDM-Accel and aging trajectories were assessed using multiple linear regression and multivariable logistic regression, respectively. GBTM identified three distinct aging trajectories: slow aging (14.86%), moderately accelerated aging (59.14%), and rapidly accelerated aging (26%). Higher concentrations of urinary Σ-OHPAHs (sum of all metabolites), 1-hydroxypyrene (1-OHPyr), and 2-hydroxyphenanthrene (2-OHPhe) were significantly associated with increased KDM-Accel. A natural log-unit increase in Σ-OHPAHs and 1-OHPyr was associated with a 0.029-year and 0.028-year increase in KDM-Accel, respectively. Workers in the highest tertile (T3) of Σ-OHPAHs exposure had a 61.2% increased odds (OR = 1.612, 95% CI 1.093–2.376) of being in the rapidly accelerated aging trajectory compared to those in the lowest tertile (T1). Similar positive dose-response relationships were observed. Occupational exposure to PAHs, as specifically indicated by elevated levels of urinaryΣ-OHPAHs, 1-OHPyr, and 2-OHPhe, is correlated with accelerated biological aging and a heightened probability of a rapid aging trajectory. Therefore, enhanced protection measures and early intervention strategies are necessary.

The online version contains supplementary material available at 10.1038/s41598-026-36579-y.