As concern regarding the toxic effects of bisphenol A (BPA) grows, BPA in many consumer products is gradually being replaced with compounds such as bisphenol S (BPS). Nevertheless, data on the occurrence of BPS in human specimens are limited. In this study, 315 urine samples, collected from the general populations in the United States, China, India, Japan, Korea, Kuwait, Malaysia, and Vietnam, were analyzed for the presence of total BPS (free plus conjugated) concentrations by highperformance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). BPS was detected in 81% of the urine samples analyzed at concentrations ranging from below the limit of quantitation (LOQ; 0.02 ng/mL) to 21 ng/mL (geometric mean: 0.168 ng/mL). The urinary BPS concentration varied among countries, and the highest geometric mean concentration [1.18 ng/mL or 0.933 μg/g creatinine (Cre)] of BPS was found in urine samples from Japan, followed by the United States (0.299 ng/mL, 0.304 μg/g Cre), China (0.226 ng/mL, 0.223 μg/g Cre), Kuwait (0.172 ng/mL, 0.126 μg/g Cre), and Vietnam (0.160 ng/mL, 0.148 μg/g Cre). Median concentrations of BPS in urine samples from the Asian countries were 1 order of magnitude lower than the median concentrations reported earlier for BPA in the same set of samples, with the exception of samples from Japan.

As the concern over the safety of bisphenol A (BPA) continues to grow, this compound is gradually being replaced, in industrial applications, with compounds such as bisphenol F (BPF) and bisphenol S (BPS). Occurrence of bisphenols, including BPA and BPS, has been reported in paper products and in environmental matrices. Information on the occurrence of bisphenols, other than BPA, in foodstuffs, however, is scarce. In this study, several bisphenol analogues, including BPA, BPF, and BPS, were analyzed in foodstuffs (N = 267) collected from Albany, NY, USA, using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Foodstuffs were divided into nine categories of beverages, dairy products, fats and oils, fish and seafood, cereals, meat and meat products, fruits, vegetables, and "others". Bisphenols were found in the majority (75%) of the food samples, and the total concentrations of bisphenols (ΣBPs: sum of eight bisphenols) were in the range of below the limit of quantification (LOQ) to 1130 ng/g fresh weight, with an overall mean value of 4.38 ng/g. The highest overall mean concentration of ΣBPs was found in the "others" category, which included condiments (preserved, ready-to-serve foods). A sample of mustard (dressing) and ginger, placed in the category of vegetables, contained the highest concentrations of 1130 ng/g for bisphenol F (BPF) and 237 ng/g for bisphenol P (BPP). Concentrations of BPs in beverages (mean = 0.341 ng/g) and fruits (0.698 ng/g) were low. The predominant bisphenol analogues found in foodstuffs were BPA and BPF, which accounted for 42 and 17% of the total BP concentrations, respectively. Canned foods contained higher concentrations of individual and total bisphenols in comparison to foods sold in glass, paper, or plastic containers. On the basis of measured concentrations and daily ingestion rates of foods, the daily dietary intakes of bisphenols (calculated from the mean concentration) were estimated to be 243, 142, 117, 63.6, and 58.6 ng/kg body weight (bw)/day for toddlers, infants, children, teenagers, and adults, respectively.

As the evidence of the toxic effects of bisphenol A (BPA) grows, its application in commercial products is gradually being replaced with other related compounds, such as bisphenol S (BPS). Nevertheless, very little is known about the occurrence of BPS in the environment. In this study, BPS was analyzed in 16 types of paper and paper products (n = 268), including thermal receipts, paper currencies, flyers, magazines, newspapers, food contact papers, airplane luggage tags, printing paper, kitchen rolls (i.e., paper towels), and toilet paper. All thermal receipt paper samples (n = 111) contained BPS at concentrations ranging from 0.0000138 to 22.0 mg/g (geometric mean: 0.181 mg/g). The overall mean concentrations of BPS in thermal receipt papers were similar to the concentrations reported earlier for BPA in the same set of samples. A significant negative correlation existed between BPS and BPA concentrations in thermal receipt paper samples (r = −0.55, p < 0.0001). BPS was detected in 87% of currency bill samples (n = 52) from 21 countries, at concentrations ranging from below the limit of quantification (LOQ) to 6.26 μg/g (geometric mean: 0.029 μg/g). BPS also was found in 14 other paper product types (n = 105), at concentrations ranging from 88%). To our knowledge, this is the first report on the occurrence of BPS in paper products and currency bills.

Bisphenol A has been reported to be a ubiquitous contaminant in indoor dust, and human exposure to this compound is well documented. Information on the occurrence of and human exposure to other bisphenol analogues is limited. In this study, eight bisphenol analogues, namely 2,2-bis(4-hydroxyphenyl)propane (BPA), 4,4'-(hexafluoroisopropylidene)diphenol (BPAF), 4,4'-(1-phenylethylidene)bisphenol (BPAP), 2,2-bis(4-hydroxyphenyl)butane (BPB), 4,4'-dihydroxydiphenylmethane (BPF), 4,4'-(1,4-phenylenediisopropylidene)bisphenol (BPP), 4,4'- sulfonyldiphenol (BPS), and 4,4'-cyclohexylidenebisphenol (BPZ), were determined in indoor dust samples (n = 156) collected from the United States (U.S.), China, Japan, and Korea. Samples were extracted by solid-liquid extraction, purified by automated solid phase extraction methods, and determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The total concentrations of bisphenols (∑BPs; sum of eight bisphenols) in dust were in the range of 0.026-111 μg/g (geometric mean: 2.29 μg/g). BPA, BPS, and BPF were the three major bisphenols, accounting for >98% of the total concentrations. Other bisphenol analogues were rare or not detected, with the exception of BPAF, which was found in 76% of the 41 samples collected in Korea (geometric mean: 0.0039 μg/g). The indoor dust samples from Korea contained the highest concentrations of both individual and total bisphenols. BPA concentrations in dust were compared among three microenvironments (house, office, and laboratory). The estimated median daily intake (EDI) of ∑BPs through dust ingestion in the U.S., China, Japan, and Korea was 12.6, 4.61, 15.8, and 18.6 ng/kg body weight (bw)/day, respectively, for toddlers and 1.72, 0.78, 2.65, and 3.13 ng/kg bw/day, respectively, for adults. This is the first report on the occurrence of bisphenols, other than BPA, in indoor dust.

Bisphenol A (BPA) is used in a variety of consumer products, including some paper products, particularly thermal receipt papers, for which it is used as a color developer. Nevertheless, little is known about the magnitude of BPA contamination or human exposure to BPA as a result of contact with paper and paper products. In this study, concentrations of BPA were determined in 15 types of paper products (n = 202), including thermal receipts, flyers, magazines, tickets, mailing envelopes, newspapers, food contact papers, food cartons, airplane boarding passes, luggage tags, printing papers, business cards, napkins, paper towels, and toilet paper, collected from several cities in the USA. Thermal receipt papers also were collected from Japan, Korea, and Vietnam. BPA was found in 94% of thermal receipt papers (n = 103) at concentrations ranging from below the limit of quantitation (LOQ, 1 ng/g) to 13.9 mg/g (geometric mean: 0.211 mg/g). The majority (81%) of other paper products (n = 99) contained BPA at concentrations ranging from below the LOQ to 14.4 μg/g (geometric mean: 0.016 μg/g). Whereas thermal receipt papers contained the highest concentrations of BPA (milligram-per-gram), some paper products, including napkins and toilet paper, made from recycled papers contained microgram-per-gram concentrations of BPA. Contamination during the paper recycling process is a source of BPA in paper products. Daily intake (DI) of BPA through dermal absorption was estimated based on the measured BPA concentrations and handling frequency of paper products. The daily intake of BPA (calculated from median concentrations) through dermal absorption from handling of papers was 17.5 and 1300 ng/day for the general population and occupationally exposed individuals, respectively; these values are minor compared with exposure through diet. Among paper products, thermal receipt papers contributed to the majority (>98%) of the exposures.

Exposure of humans to bisphenol A (BPA), a widely used industrial chemical, is well-known. In humans and animals, conjugation of BPA molecule with glucuronide or sulfate is considered as a mechanism for detoxification. Nevertheless, very few studies have directly measured free, conjugated (e.g., glucuronidated), and substituted (e.g., chlorinated) forms of BPA in human specimens. In this study, free, conjugated (BPA glucuronide or BPAG and BPA disulfate or BPADS), and substituted (chlorinated BPA; mono- [BPAMC], di-[BPADC], and trichloride [BPATrC]) forms of BPA were determined in human urine and serum samples, using solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) techniques. The instrumental calibration for each of the target compounds ranged from 0.01 to 100 ng/mL and showed excellent linearity (r > 0.99). The limits of quantification (LOQs) were 0.01 ng/mL for free BPA and 0.05 ng/mL for the conjugated and substituted BPA. Respective recoveries of the six target compounds spiked into water blanks and sample matrices (urine and serum), and passed through the entire analytical procedure, were 96 ± 14% and 105 ± 18% (mean ± SD) for urine samples and 87 ± 8% and 80 ± 13% for serum samples. The optimal recoveries of BPAG and BPADS in the analytical procedure indicted that no deconjugation occurred during the SPE procedure. The method was applied to measure six target chemicals in urine and serum samples collected from volunteers in Albany, New York. BPA and its derivatives were found in urine samples at concentrations ranging from < LOQ to a few tens of ng/mL. In serum, free and conjugated BPA were detected at sub ng/mL concentrations, whereas BPA chlorides were not detected. The urine and serum samples were also analyzed by enzymatic deconjugation and liquid-liquid extraction (LLE) for the determination of total BPA, and the results were compared with those measured by the SPE method. To our knowledge, this is the first report on the occurrence of BPAG and BPADS in human serum.

Persistent organic pollutants (POPs) have been of considerable public health and environmental concern for several decades. These are organic substances that persist in the environment, can undergo long distance transportation, are able to bioaccumulate, and pose a risk of causing adverse effects to animals and human health. As a measure to control and mitigate the threats of POPs, an international treaty was signed in 2001 and came into force on May 2004 for its signatories (1). The treaty, called the Stockholm Convention on Persistent Organic Pollutants (SC), initially listed twelve chemicals, the so-called "Dirty Dozen" for final elimination (Annex A), or restricted use (Annex B), and/or reduced releases of unintentional production (Annex C). The SC also included a section stating that additional chemicals can be nominated by its member parties, after which the candidate chemical would undergo several screening and evaluation rounds before it could be voted for inclusion into the Convention (Figure 1). The (possible) inclusion of one of these suspected POPs, perfluorooctane sulfonate (PFOS), is currently a controversial issue and we provide some of our viewpoints below, mainly concerning the current production pattern, adverse health effects, and economical issues. Review documents were mainly cited due to limitations on article length, and interested readers are advised to consult relevant articles cited within these reviews.

Bisphenol A (BPA) is an industrial chemical used in the manufacture of polycarbonate plastics and epoxy resins. Due to the potential of this compound to disrupt normal endocrinal functions, concerns over human exposure to BPA have been raised. Although several studies have reported human exposure to BPA in Western nations, little is known about exposure in Asian countries. In this study, we determined total urinary BPA concentrations (free plus conjugated) in 296 urine samples (male/female: 153/143) collected from the general population in seven Asian countries, China, India, Japan, Korea, Kuwait, Malaysia, and Vietnam, using high-performance liquid chromatography (HPLC) tandem mass spectrometry (MS/MS). On the basis of urinary BPA concentrations, we estimated the total daily intake. The results indicated that BPA was detected in 94.3% of the samples analyzed, at concentrations ranging from <0.1 to 30.1 ng/mL. The geometric mean concentration of BPA for the entire sample set from seven countries was 1.20 ng/mL. The highest concentration of BPA was found in samples from Kuwait (median: 3.05 ng/mL, 2.45 μg/g creatinine), followed by Korea (2.17 ng/mL, 2.40 μg/g), India (1.71 ng/mL, 2.09 μg/g), Vietnam (1.18 ng/mL, 1.15 μg/g), China (1.10 ng/mL, 1.38 μg/g), Malaysia (1.06 ng/mL, 2.31 μg/g), and Japan (0.95 ng/mL, 0.58 μg/g). Among the five age groups studied (≤ 19, 20-29, 30-39, 40-49, and ≥ 50 years), the highest median concentration of BPA was found in urine samples from the age group of ≤ 19 years. There was no significant difference in BPA concentrations between genders (male and female) or domicile of residence (rural and urban). The estimated median daily intakes of BPA for the populations in Kuwait, Korea, India, China, Vietnam, Malaysia, and Japan were 5.19, 3.69, 2.90, 2.13, 2.01, 1.80, and 1.61 μg/day, respectively. The estimated daily intake of BPA in the seven Asian countries was significantly lower than the tolerable daily intake recommended by the U.S. Environmental Protection Agency. This is the first study to document the occurrence of and human exposure to BPA in several Asian countries.