Association Between Blood Benzene Levels and Periodontal Disease in a Nationally Representative Adult U.S. Population

(1) Background: Benzene, environmental pollutant, is linked to various adverse health effects, but its impact on oral health remains under-explored. This study examines the association between blood benzene levels and periodontitis, a progressive oral inflammatory condition, using a nationally representative sample of U.S. adults. (2) Methods: Cross sectional data from the 2013–2014 National Health and Nutrition Examination Survey (NHANES) were analyzed. Periodontitis was defined per CDC/AAP. Three weighted multivariable logistic regression models determined the association between blood benzene levels and periodontal severity, adjusting for potential confounders. A structural equation modeling (SEM) analysis evaluated cotinine, smoking biomarker, as a mediator in the relationship between benzene and severe periodontitis. (3) Results: The ordinal logistic regression showed a statistically significant association (AOR = 2.0, p = 0.02) between blood benzene levels and periodontal severity. A one unit increase in blood benzene was associated twice the odds of progressing to a higher category of periodontitis. Benzene exposure was significantly linked to severe periodontitis (AOR = 2.9, p = 0.001). SEM analysis indicated cotinine mediates the relationship between blood benzene and sever periodontitis. (4) Conclusions: This study provides evidence that higher blood benzene levels are associated with severe periodontitis. The findings suggest that cotinine, a biomarker of smoking, mediates the relationship between benzene exposure and severe periodontitis.