The association between urinary polycyclic aromatic hydrocarbon metabolites and atopic triad by age and body weight in the US population

Background Polycyclic aromatic hydrocarbons (PAHs) are generated during the incomplete combustion of coal/oil/gas and waste. The role of PAH exposure in the atopic triad remains poorly understood. Due to their lipophilic nature, PAHs deposit in adipocytes, potentially placing elderly and those who are overweight at higher risk. Objective To investigate the association between urinary PAHs and symptoms of atopic triad (chronic pruritus, sneezing, and wheezing). Methods Binary multivariable logistic regression was performed to estimate the association of nine urinary PAHs and atopic diseases followed by subgroup analyses by age (children 6-17, adults 18-49, elderly >= 50 years) and body mass index (BMI) (normal: BMI <25, overweight: BMI >= 25 kg/m(2)) among 2,242 participants of National Health and Nutrition Examination Survey 2005-2006 dataset. Results 1-hydroxynaphthalene (1-NAP) and hydroxyfluorenes (FLUs) were positively associated with wheezing. When stratified by age, positive associations were found between 1-NAP with wheezing in children/adults and 2-/3-FLU with wheezing in adults/elderly. 3-hydroxyphenanthrene (3-PHE) and 1-hydroxypyrene were positively associated with chronic pruritus in elderly. When stratified by BMI, positive associations were found between 2-PHE with chronic pruritus, 1-NAP and FLUs with wheezing in overweight. Conclusion Urinary PAH levels were positively associated with atopic triad and this connection was influenced by age and BMI.