Abstract Thermochromic inks, materials that change color at a certain temperature, are increasingly used on papers and other materials in the areas of design, commercials, and security printing. Pseudo-estrogen bisphenol A (BPA) may be one of their main compounds present in mass fractions of up to several percent. In this work, the mass fractions of BPA in thermochromic prints on seven types of paper were determined. Migration of BPA from the surface of the thermochromic print to artificial sweat solutions was investigated as well. Total amount of BPA in papers with thermochromic prints was determined by an HPLC-UV method with ultrasonic-assisted extraction in methanol developed and validated in this work. Total amount of BPA, which ranged from 0.126 to 0.778 mg/g, was compared with the amounts extracted under the same conditions in two artificial human sweat solutions, which differed in chemical composition, ionic strength, and pH-value. Mass fractions of BPA extracted with artificial sweat solutions were from 0.047 to 0.175 mg/g with respect to the mass of the paper. On average, the mass fraction of BPA was four times less when extracted with artificial sweat solutions than the maximal amount extracted with methanol. The amounts of extracted BPA raise a concern of health risk through dermal exposure to BPA from thermochromic prints on paper. GRAPHICAL ABSTRACT

中文翻译：

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假雌激素双酚 A 从具有热致变色印刷的各种类型的纸张迁移到人造汗液溶液中

摘要 热致变色油墨是一种在一定温度下变色的材料，越来越多地用于设计、商业广告和安全印刷领域的纸张和其他材料。假雌激素双酚 A (BPA) 可能是它们的主要化合物之一，质量分数高达几个百分点。在这项工作中，确定了七种纸张上热致变色印刷品中 BPA 的质量分数。还研究了 BPA 从热致变色印花表面迁移到人造汗液溶液中。本研究开发并验证了在甲醇中采用超声波辅助萃取的 HPLC-UV 方法测定了热致变色印刷纸中 BPA 的总量。BPA 的总量，范围从 0.126 到 0.778 mg/g，与在相同条件下在化学成分、离子强度和 pH 值不同的两种人造人体汗液中提取的量进行比较。相对于纸的质量，用人造汗液提取的 BPA 的质量分数为 0.047 至 0.175 mg/g。平均而言，用人造汗液提取的 BPA 的质量分数是用甲醇提取的最大量的四倍。提取的 BPA 的数量引起了人们对皮肤接触来自纸上热致变色印刷品的 BPA 的健康风险的担忧。图形概要 用人造汗液提取的 BPA 的质量分数是用甲醇提取的最大量的四倍。提取的 BPA 的数量引起了人们对皮肤接触来自纸上热致变色印刷品的 BPA 的健康风险的担忧。图形概要 用人造汗液提取的 BPA 的质量分数是用甲醇提取的最大量的四倍。提取的 BPA 的数量引起了人们对皮肤接触来自纸上热致变色印刷品的 BPA 的健康风险的担忧。图形概要