Presentations

Abstract

Introduction:

An organic UV filter, benzophenone-3 (BP3) is widely used in sunscreens. The water resistance, minimal white cast after application, and non-greasiness of BP3 containing sunscreens make them appealing to users. Conversely, BP3 may be absorbed through the skin, excreted in the urine, and disrupt hormones. Additionally, animal models and in vitro human lymphocyte studies have shown that BP3 has immunomodulatory effects and increases inflammatory cytokines. However, the association between BP3 and white blood cells (WBC) using large cohort of the United States population has not been explored.

Methods:

We used the continuous NHANES data from 2003-2016. Urinary BP3 and urinary creatinine were used to calculate creatinine-normalized urinary BP3 (CnBP3) to account for urinary dilution/concentration. We used linear regression models with adjustments for age, gender, race, body mass index (BMI), smoking, season, family income to poverty ratio (FIPR), and survey cycle.

Results:

Of the 18,096 participants, 9,128 (50.4%) were female, 6,937 (38.3%) were White, 4,266 (23.6%) were Black, 5,181 (28.6%) were Hispanic, and 6,665 (55.1%) were non-smokers. Mean (SD) age was 36.9 (22.8) years, BMI 26.6 (7.43) kg/m2, and WBC 7.22 (2.53) 109/L. In adjusted models, highest quintile individuals had lower WBC count than those in the lowest quintile (-173 x 106/L; 95%CI=-320, -26; P=0.02). Among WBC subsets, neutrophil count was associated with CnBP3 (highest vs. lowest quintiles = -132 x 106/L; 95%CI=-246, -17; P=0.02) but not lymphocyte count.

Conclusion:

Higher CnBP3 levels were associated with statistically significant decrease in WBC and neutrophil counts, but not lymphocytes. Potential anti-inflammatory effects of BP3 found in our study need further exploration.