Estimating Benzene Exposure Level over Time and by Industry Type through a Review of Literature on Korea

The major purpose of this study is to construct a retrospective exposure assessment for benzene through a review of literature on Korea. Airborne benzene measurements reported in 34 articles were reviewed. A total of 15,729 individual measurements were compiled. Weighted arithmetic means [AM(w)] and their variance calculated across studies were summarized according to 5-year period intervals (prior to the 1970s through the 2010s) and industry type. Industries were classified according to Korea Standard Industrial Classification (KSIC) using information provided in the literature. We estimated quantitative retrospective exposure to benzene for each cell in the matrix through a combination of time and KSIC. Analysis of the AM(w) indicated reductions in exposure levels over time, regardless of industry, with mean levels prior to the 1980e1984 period of 50.4 ppm (n = 2,289), which dropped to 2.8 ppm (n = 305) in the 1990e1994 period, and to 0.1 ppm (n = 294) in the 1995e1999 period. There has been no improvement since the 2000s, when the AM(w) of 4.3 ppm (n = 6,211) for the 2005e2009 period and 4.5 ppm (n = 3,358) for the 2010e2013 period were estimated. A comparison by industry found no consistent patterns in the measurement results. Our estimated benzene measurements can be used to determine not only the possibility of retrospective exposure to benzene, but also to estimate the level of quantitative or semiquantitative retrospective exposure to benzene.

Association between Insulin Resistance and Benign Prostatic Hyperplasia in Healthy Middle-aged Korean Men

BACKGROUND: We examined the association between insulin resistance assessed by homeostatic model assessment-insulin resistance (HOMA-IR) and benign prostatic hyperplasia (BPH) in healthy middle-aged male subjects. METHODS: A cross-sectional study included 1,727 male subjects, aged 40-59 year, free of medication history for BPH who received a transrectal ultrasonography and completed a structured questionnaire in 2011. Multiple logistic regression analysis was performed to evaluate the relationships of HOMA-IR with BPH across the tertile of HOMA-IR. RESULTS: The prevalence of BPH was 24.4% (421 out of 1,727). It was increased across HOMA-IR tertiles in crude and age-adjusted models. In a multivariable-adjusted model after adjusting potential confounders such as age, body mass index (BMI), triglyceride, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), alcohol consumption, smoking, exercise and meat consumption, odds ratios (95% confidence intervals, CIs) of BPH for 2nd tertile and 3rd tertile compared to 1st tertile were 1.76 (1.31-2.35), and 1.83 (1.34-2.48), respectively. CONCLUSIONS: In middle-aged, healthy men, higher HOMA-IR was significantly associated with higher prevalence of BPH, supporting insulin resistance as an independent risk factor for BPH.