Highway proximity associations with blood markers of inflammation: evidence for a role for IL-1β.

Cardiovascular disease is known to be associated with proximity to major roadways and highways. Thus, blood samples from 20 near highway and 20 urban background residents were analyzed for presence of cytokines and other biomarkers. Near-highway participants displayed significantly lower socioeconomic status (SES) and significantly higher occupational vehicle exhaust exposure and higher low-density lipoprotein (LDL) levels. Controlling for exposure to vehicle exhaust on the job, interleukin-6 (IL-6) was numerically higher in near highway participants. Using logistic regression analyses, IL-1β was significantly elevated near highway. It is interesting that elevations were found in IL-1β, a key cytokine linked to inflammation from particulate matter (PM). More studies are needed with larger sample sizes to assess the possible role of IL-1β.