Bisphenol A levels in blood and urine in a Chinese population and the personal factors affecting the levels

The objective of the study was to describe the background bisphenol A (BPA) levels in urine and serum of a Chinese population without occupational exposure and to examine the personal characteristics influencing these levels. Workers from 10 factories and their family members were recruited and their peripheral blood and spot urine samples were collected. The conjugated and free BPA of the samples was assayed with high-performance liquid chromatography. The exposure levels were checked with 2-independent-samples test, and the potential personal factors influencing exposure levels were analyzed using nonlinear correlation. Of the total of 952 subjects participating in the study, urine and blood samples were taken from 97% and 93% of them, respectively. The detectable rates were 50% for urine samples and 17% for serum samples, given the detection limit of 0.31 μg/L for urine and 0.39 μg/L for serum. The arithmetic mean (AM) and geometric mean (GM) of non-creatinine-adjusted urinary BPA level were 10.45 and 0.87 μg/L, which became 24.93 and 0.38 μg/g Cr after the creatinine level was adjusted; serum BPA levels were 2.84 μg/L (AM) and 0.18 μg/L (GM). Males and those with smoking habit had higher biological burden of BPA. The results indicated that half of the study subjects had detectable BPA in their urine samples. BPA levels were influenced by gender and smoking status. The sources of non-occupational BPA exposures should be explored.