Contents lists available at ScienceDirect Environment International journal homepage: www.elsevier.com/locate/envint Bisphenol A exposure through receipt handling and its association with insulin resistance among female cashiers Inae Lee a , Sunmi Kim a , Ki-Tae Kim b , Sungkyoon Kim a , Suhyun Park a , Hyojin Lee b , Yunsun Jeong c , Jae-Eun Lim c , Hyo-Bang Moon c , Kyungho Choi a,d, ⁎ a School of Public Health, Seoul National University, Seoul, Republic of Korea b Department of Environmental Engineering, Seoul National University of Science and Technology, Seoul, Republic of Korea c Department of Marine Science and Convergence Engineering, Hanyang University, Ansan, Republic of Korea d Institute of Health and Environment, Seoul National University, Seoul, Republic of Korea ARTICLE INFO Handling Editor: Lesa Aylward Keywords: Bisphenol A Receipt Cashier Dermal exposure Metabolic syndrome ABSTRACT Bisphenol A (BPA) is one of the most widely used chemicals in various consumer products. In thermal papers such as receipts and tickets, BPA is used as a heat-activated developer. Cashiers are therefore suspected to be a vulnerable group of exposure to BPA, but neither contribution of receipt handling to the total body burden of BPA among cashiers, nor related health effects are well characterized. Female cashiers (n = 54) were recruited from seven retail shops of a major supermarket chain in Korea, and urinary levels of BPA and metabolic syn- drome (MetS) related biomarkers were measured. In order to estimate the contribution of receipt handling to the body burden of BPA, an intervention was designed on the use of gloves: the subjects were asked not to wear gloves during the work for one week, and in the following week, to wear gloves. Urine samples were collected at pre-shift and post-shift for the first two consecutive days in each week, and urinary BPA concentrations were measured. In cashiers without gloves, about a two-fold increase in urinary BPA concentrations was observed after work-shift. When the cashiers wore gloves, however, urinary BPA levels showed no changes. Higher urinary BPA concentrations were associated with greater levels of fasting insulin and insulin resistance. Our observation shows that receipt handling among the cashiers could double the BPA exposure levels at post-shift compared to those at pre-shift, and use of simple protective equipment such as gloves could effectively reduce the BPA exposure levels. 1. Introduction Bisphenol A (BPA, 2,2-bis(4-hydroxyphenyl) propane) is used in polycarbonate plastic and epoxy resin production. Due to its extensive usage, BPA ubiquitously exists in the living environment, leading to widespread exposure to humans (Geens et al., 2012). Oral exposure via consumption of food or drink is considered to be one of the major routes of exposure to BPA (von Goetz et al., 2010). Food is estimated to account for > 90% of total BPA exposure for all of the age groups with median levels of exposure (Geens et al., 2012). Despite the high contribution of food in BPA exposure, other exposure sources such as thermal papers cannot be ignored. Free BPA is coated on thermal paper as a heat-activated print developer (Mendum et al., 2011), and can be readily transferred to skin when being contacted (Liao and Kannan, 2011). Cashiers are one of the groups most frequently in contact with re- ceipts through work-shift, and therefore considered to be a vulnerable group of BPA exposure. The amount of occupational dermal exposure to BPA has been estimated to be 50- to 3366-folds greater than that esti- mated for the general population (Liao and Kannan, 2011; Lu et al., 2013; Fan et al., 2015; Rocha et al., 2015). However, these exposure estimates might be exaggerated because most of such studies are based on conservative exposure scenarios with significant uncertainties. A few experimental studies have been also reported, but observations are often conflicting. In an experimental study employing volunteers (n = 23), continuous contact with receipts for 2 h led to significantly higher levels of BPA (Ehrlich et al., 2014). In another simulation study, however, holding receipts for 5 s every 3 min during work-shift of 8 h did not result in changes in urinary BPA levels (Porras et al., 2014). Well-designed human observation study is warranted in order to https://doi.org/10.1016/j.envint.2018.05.013 Received 26 January 2018; Received in revised form 5 May 2018; Accepted 5 May 2018 ⁎ Corresponding author at: Department of Environmental Health Sciences, School of Public Heath, Seoul National University, Seoul 08826, Republic of Korea. E-mail address: kyungho@snu.ac.kr (K. Choi). Abbreviation: BMI, body mass index; BPA, bisphenol A; BPS, bisphenol S; HDL, high-density lipoprotein; LDL, low-density lipoprotein; HOMA-IR, homeostatic model assessment of insulin resistance; LOQ, limit of quantification; MetS, metabolic syndrome; SG, specific gravity Environment International 117 (2018) 268–275 0160-4120/ © 2018 Elsevier Ltd. All rights reserved. T