Details

Autor(en) / Beteiligte

• Werder, Emily J.
• Engel, Lawrence S.
• Blair, Aaron
• Kwok, Richard K.
• McGrath, John A.
• Sandler, Dale P.

Titel

Blood BTEX levels and neurologic symptoms in Gulf states residents

Ist Teil von

• Environmental research, 2019-08, Vol.175, p.100-107

Ort / Verlag

Netherlands: Elsevier Inc

Erscheinungsjahr

2019

Quelle

MEDLINE

Beschreibungen/Notizen

• The chemicals benzene, toluene, ethylbenzene, and xylenes (BTEX) are neuroactive. Exposures often co-occur because they share common sources. We examined neurologic effects of environmental BTEX exposure among U.S. Gulf coast residents taking into account concomitant exposures. We measured blood concentrations of BTEX in 690 Gulf state residents. Neurologic symptoms were ascertained via telephone interview. We used log-binomial regression to estimate associations between blood BTEX levels and self-reported neurologic symptoms independently for the presence of any neurologic, central (CNS), or peripheral nervous system (PNS) symptoms. We estimated associations in single chemical models mutually adjusted for co-occurring BTEX and used weighted quantile sum regression to model associations between the combined BTEX mixture and neurologic symptoms. Half (49%) of participants reported at least one neurologic symptom. Each BTEX chemical was associated with increased CNS and PNS symptoms in single-chemical models comparing the highest to lowest quartile of exposure. After adjusting for coexposures, benzene was associated with CNS symptoms among all participants (PR = 2.13, 95% CI: 1.27, 3.57) and among nonsmokers (PR = 2.30, 95% CI: 1.35, 3.91). After adjusting for coexposures, associations with toluene were apparent only for reporting multiple PNS symptoms (PR = 2.00, 95% CI: 0.96, 4.16). In mixture analyses, a one-quartile increase in BTEX exposure was associated with neurologic symptoms (OR = 1.47, 95% CI: 1.11, 1.98). The weighted quantile sum index weighted benzene most heavily, which was consistent with single chemical analyses. Increasing blood benzene concentration was associated with increased prevalence of CNS symptoms. In this sample, BTEX-associated neurologic effects are likely driven by exposure to benzene and, to a lesser extent, toluene. •Environmental blood BTEX levels are associated with neurologic symptoms.•Blood benzene appears to be the agent driving associations in mixture analyses.•Blood benzene is consistently associated with symptoms of central nervous symptom impairment.•Blood toluene may be associated with symptoms of peripheral nervous system impairment.