David O. Carpenter

Background: Polychlorinated biphenyls (PCBs) persist in the environment and have been associated with cardiovascular disease (CVD). We examined whether routine cardiometabolic biomarkers statistically accounted for this association. Methods: This cross-sectional analysis used NHANES 1999–2002 data for 2815 adults aged 20 years or older. Lipid-adjusted total PCB burden was the sum of 21 congeners. Survey-weighted logistic regression estimated odds ratios for prevalent CVD, restricted cubic splines examined the exposure–response shape, and mediator-specific structural equation models evaluated indirect and residual pathways through CRP, HbA1c, waist circumference, central obesity, the total cholesterol/HDL ratio, and a binary high-ratio measure. Results: Weighted mean total PCB burden was 234.6 ng/g lipid, and weighted CVD prevalence was 8.9%. A 1-unit increase in the natural log of total PCB burden was associated with higher odds of prevalent CVD after full adjustment (aOR = 1.36, 95% CI: 1.01–1.84). Coronary heart disease and angina showed the clearest subtype associations. The spline analysis did not detect nonlinearity. Indirect estimates through CRP, waist circumference, and the TC/HDL ratio were negative, which is consistent with statistical suppression; estimates through the other biomarkers were small and imprecise. Conclusions: Higher serum PCB burden was associated with prevalent CVD after adjustment for major demographic and cardiometabolic factors. In cross-sectional pathway models, routine biomarkers did not account for most of this association. Longitudinal studies are needed before these statistical pathways can be interpreted as causal mechanisms.

Madinah, Saudi Arabia, is a hot-desert pilgrimage city receiving millions of religious visitors annually, yet its fine particulate matter (PM_2.5) has not been chemically characterized. The city whose population is periodically influx by millions of religious visitors, generating concentrated increases in vehicular activity while simultaneously exposing a large transient population to ambient air pollution. Despite this, its fine particulate matter (PM_2.5) has not been chemically characterized. Twenty-four-hour PM_2.5 samples were collected at five urban sites between December 2014 and February 2016 and analyzed for black carbon, water-soluble inorganic ions, and trace elements; sources were resolved by enrichment factors and positive matrix factorization (PMF), and screening-level inhalation risks estimated for eight PM_2.5-bound metals. Site means ranged from 37.7 ± 20.5 µg m⁻³ at Uhad to 103 ± 50.7 µg m⁻³ at Al-Awali, exceeding the World Health Organization 24-h guideline of 15 µg m⁻³ at all sites in every season. Observed site–cycle means ranged from 37.7 ± 20.5 µg m⁻³ at Uhad to 103 ± 50.7 µg m⁻³ at Al-Awali, with concentrations exceeding the World Health Organization 24-h guideline of 15 µg m⁻³ across the monitored site–cycle datasets. Reconstructed mass was dominated by organic matter (53–80.5%) and crustal material (15–53%). Sulfate was the dominant water-soluble ion, but secondary inorganic aerosols contributed only 1–22% of mass, resembling rapidly urbanizing arid cities rather than Asian or European megacities. PMF resolved five sources: crustal dust, industrial mixed dust, oil combustion, vehicular emissions, and secondary aerosols. Hazard quotients remained below unity and cumulative carcinogenic risks below 10⁻⁶, principally from chromium and nickel. Because these measurements precede the Vision 2030 urban-transformation program, they establish a chemically resolved reference state for evaluating future air-quality change in Madinah.

Fine particulate matter (PM_2.5) composition, rather than mass alone, plays a critical role in determining toxicity and health impact. This study examined short-term associations between daily PM_2.5 constituents—black carbon (BC), nitrate (NO₃⁻), ammonium (NH₄⁺), and trace elements—and cardiopulmonary hospital admissions in Makkah, Saudi Arabia. Twelve months of constituent data from the Alharam monitoring site were linked to Herra hospital admissions for cardiovascular (CVD) and pulmonary diseases, stratified by visit type, age, and sex. Negative-binomial generalized linear models estimated adjusted relative risks (aRRs) per interquartile range increase in each constituent, controlling for meteorology, seasonality, and temporal trends. Mean PM_2.5 was 113.6 µg/m³; BC, sulfur, NO₃⁻, and NH₄⁺ dominated the fine fraction. Crustal elements were strongly intercorrelated (r > 0.9), while BC, lead (Pb), and nickel (Ni) showed moderate correlations (r ≈ 0.4–0.6), suggesting shared anthropogenic origins. BC increased CVD emergency/outpatient visits by 18% (aRR = 1.18; 95% CI: 1.08–1.29) and inpatient admissions by 25% (aRR = 1.25; 95% CI: 1.07–1.46). Ni and sulfur were also significant predictors; crustal elements were not. Multi-pollutant models confirmed BC and Pb as independent predictors (aRR = 1.19; 95% CI: 1.02–1.38). Effects were strongest among older adults aged 45–65 at lag 0–2 days. These findings highlight the need for emission controls targeting traffic and industrial combustion sources.

Background: Mixtures of criteria air pollutants (CAPs) and volatile organic compounds (VOCs) can interact synergistically, causing greater respiratory harm than the individual components, including asthma exacerbation and reduced lung function. However, while VOCs are recognized air pollutants and potential for synergy is known, prior work on mixture effects is limited to CAP mixtures. Objectives: Using data from the National Emissions Inventory, we assessed county level mixture effects of zip code level point source air pollution emissions on emergency room (ER) visits for asthma and COPD in New York State from 2010 to 2018. Methods: We explored mixture effects of 10 air pollutants on outpatient admissions for asthma and chronic obstructive pulmonary disease (COPD), using a complementary multi-model approach, including linear regression, random forest, and mixture models to assess single pollutant and mixture effects. Results: Significant pairwise interactions were identified between VOC and most CAP pollutants for both asthma and COPD. While standardized single pollutant effects were small for both conditions, standardized mixture effects for asthma without interactions were moderate (0.36, 95%CI: 0.32, 0.41, per quantile mixture increase). Including significant pairwise interactions in the model results in a 3-fold adjusted increase (1.07, 95%CI: 0.64, 1.50). Results for COPD are similar but less striking. Conclusion: Our findings show that point source pollution offers a significant contribution to risk of asthma and COPD-related visits, effects vary by illness and location, and pairwise interactions between mixture components, especially between VOC and CAPs, may dramatically increase case rates.

We assess associations between emergency room (ER) visits, scaled to per 10⁵ population per year, for asthma and chronic obstructive pulmonary disease (COPD), two of the most common respiratory diseases, and zip code-level exposure to criteria air pollutants (CAPs) coming from point sources in New York State (NYS) from 2010 to 2018. Exposure data on point source CAPs were retrieved from the United States Environmental Protection Agency (USEPA) National Emission Inventory (NEI) database, and ER visits for asthma and COPD were acquired from the New York State Department of Health (NYSDOH) Statewide Planning and Research Cooperative System (SPARCS). To account for within-county variability, we used log-linear mixed effects models, adjusted for year, sex, age category, county-level poverty, smoking, PM_2.5, volatile organic compounds (VOCs), and CAPs sources within the study period. Results show significant associations between ER visits for asthma and COPD and most of the pollutants in the study, even after adjusting for the effects of poverty and smoking. Although point source emissions comprise a small portion of total air pollution, our findings show that zip code-level point source CAPs, especially the gaseous pollutants, pose a modest but significant contribution to the risk of respiratory disease-related ER visits.

Ambient air pollution, particularly fine particulate matter (PM_2.5), poses significant health risks, especially concerning cardiovascular diseases (CVDs). This study assesses the association between PM_2.5 exposure and CVD hospital admissions (HAs) and emergency room (ER) visits in Karachi, Pakistan. Daily PM_2.5 samples were collected from four Karachi sites (Makro, Karachi University, Keamari, and Malir) between October 2009 and June 2011. CVD morbidity data, including HAs and ER visits, were gathered from major hospitals. A single-pollutant model was employed to evaluate associations between PM_2.5 levels and CVD outcomes, adjusting for meteorological variables and other potential confounders. PM_2.5 concentrations and CVD morbidity were significantly associated across all sites Stratification by age and gender revealed stronger associations among males and individuals aged 40 and above. Exposure to elevated levels of PM_2.5 in Karachi was significantly associated with increased CVD HAs and ER visits, with the highest association found between PM_2.5 exposure and arrhythmias. The study underscores the need for effective air quality management policies and interventions to reduce PM_2.5 levels. Karachi’s high PM_2.5 levels demand urgent attention from regulatory agencies and public health professionals to implement interventions that mitigate air pollution and protect vulnerable populations.

We assess associations between emergency room (ER) visits, scaled to per 105 population per year, for asthma and chronic obstructive pulmonary disease (COPD), two of the most common respiratory diseases, and zip-code level exposure to criteria air pollutants (CAPs) coming from point sources in New York State (NYS) from 2010 to 2018. Exposure data on point source CAPs was retrieved from the United States Environmental Protection Agency (USEPA) National Emission Inventory (NEI) database and ER visits for asthma and COPD were acquired from the New York State Department of Health (NYSDOH) Statewide Planning and Research Cooperative System (SPARCS). To account for within-county variability we used log-linear mixed effects models, adjusted for year, sex, age category, county level poverty, smoking, PM2.5, volatile organic compounds (VOCs) and CAPs sources within the study period. Results show significant associations between ER visits for asthma and COPD and most of the pollutants in the study, even after adjusting for the effects of poverty and smoking. The findings suggest that zip-code level point source criteria air pollutants, while comprising a small portion of total air pollution, poses a modest but significant contribution to the risk of respiratory disease-related ER visits.

Air pollution is a major environmental health hazard. This study evaluates the health risks of air pollution exposure in the megacity Karachi, Pakistan, using the cigarette-equivalent technique developed previously for translating air pollution exposure into passive cigarette equivalents. Sampling of fine particulate matter (PM_2.5), nitrogen dioxide (NO₂), and black carbon (BC) was performed at various fixed locations throughout the four seasons of the year. We evaluated the health risks of pollutants exposure using four different health endpoints including low birth weight (2.5, NO₂, and BC were 37.2, 14.8, and 1.01, respectively, (expressed as the equivalent number of passively smoked cigarettes, PSCs) while the average risks of decreased lung function were 93.9, 38.8, and 2.87. Risks of cardiovascular mortality were 51.9, 14.3, and 2.79, and those of lung cancer were 31.3, 6.47, and 1.32, respectively. The remarkably high risks are attributed to high concentrations of air pollutants. These results suggests that residents of Karachi may experience other adverse health effects beyond those typically attributed to air pollution. These PSC equivalent risks indicate a substantial potential health burden in Karachi and support the need for emission reduction efforts targeting traffic, industrial activity, and open burning. PM_2.5 and BC were measured in 2008–2011 and NO2 in 2008–2009, so the results should be interpreted as baseline risk estimates for that period rather than current (2025) concentrations.