Age and Gender Differences in Urinary Levels of Eleven Phthalate Metabolites in General Taiwanese Population after a DEHP Episode

Po-Chin Huang; Chih-Hsin Tsai; Wei-Yen Liang; Sih-Syuan Li; Wen-Harn Pan; Hung-Che Chiang

doi:10.1371/journal.pone.0133782

Abstract

Introduction

In 2011, the Taiwan FDA disclosed illegal di(2-ethylhexyl phthalate) (DEHP) and dibutyl phthalate (DBP) use in beverage and nutrition supplements. We aim to determine phthalate exposure and other relevant factors in a sample of the general Taiwanese population in order to evaluate actual phthalate exposure levels after this disclosure of DEHP use.

Method

We selected subjects aged 7 years old and older in 2013 from the general Taiwanese population. First morning urine samples from each participant were collected to analyze 11 phthalate metabolites representing 7 parent phthalates using on-line liquid chromatography/ tandem mass spectrometry. An interview questionnaire was applied to obtain participant demographic characteristics, lifestyle, and other relevant factors.

Results

The median levels of metabolites of DEHP, including mono-ethylhexyl phthalate (MEHP), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP), DBP (DnBP and DiBP), including mono-n-butyl phthalate (MnBP) and mono-iso-butyl phthalate (MiBP), and mono-ethyl phthalate (MEP) in urine samples of 290 adults/ 97 minors (<18 years) were 7.9/ 6.1, 12.6/ 17.8, 22.0/ 25.8, 25.4/ 30.8, 18.1/ 23.6, 9.4/ 13.6 and 14.5/ 12.4 μg/g creatinine, respectively. Women (≧18 years) were exposed to significantly higher levels of MEHHP (P=0.011), MECPP (P=0.01), MnBP (P=0.001) and MEP (P<0.001) than men (≧18 years), whereas no gender difference was observed in minors. We found significant higher level of MEP (creatinine-unadjusted) in subject aged between 18 to 40 years old (P<0.001), especially for women. Exposure levels of MEOHP (P<0.001), MECPP (P=0.002) and MnBP (P=0.044) in minors were significantly higher than those of adults. High frequency usage of food preservation film and bags, and personal care products are potential sources of phthalates exposure in general Taiwanese.

Conclusion

Our findings indicated that DEHP and DBP exposure in a sample of the general Taiwanese population varied by age and gender, possibly affected by different lifestyles, and continuing bio-monitoring surveillance is warranted.

Citation: Huang P-C, Tsai C-H, Liang W-Y, Li S-S, Pan W-H, Chiang H-C (2015) Age and Gender Differences in Urinary Levels of Eleven Phthalate Metabolites in General Taiwanese Population after a DEHP Episode. PLoS ONE 10(7): e0133782. https://doi.org/10.1371/journal.pone.0133782

Editor: Wei Shen, Qingdao Agricultural University, CHINA

Received: March 24, 2015; Accepted: July 1, 2015; Published: July 24, 2015

Copyright: © 2015 Huang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Data Availability: All relevant data are within the paper and its Supporting Information files.

Funding: Support was provided by National Health Research Institutes grant, 102-EH-PP05, 103-EH-PP05, 104-EH-PP05 [http://nehrc.nhri.org.tw/toxic/project_research_en.php]. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing interests: The authors have declared that no competing interests exist.

Introduction

Phthalates are widely used in many daily products such as di-2-ethylhexyl phthalate (DEHP) in plastics, toys and medical equipment; diethyl phthalates (DEP) in cosmetics and personal care products; and di-n-butyl phthalate (DnBP) in food package film and plastic products (S1 Table). Humans may be exposed to phthalates mainly through ingestion of phthalate-tainted food, or inhalation and dermal absorption of phthalate-contained products; urinary metabolites are considered to be good biomarkers for assessing their exposure [1–2]. In 2011, the Taiwan Food and Drug Administration discovered illegal-use of phthalates, such as DEHP, DnBP and di-i-butyl phthalate (DiBP) in beverage, food and nutrition supplements [3–4]. Although most contaminant products were removed and immediate regulatory action occurred, human phthalate exposure monitoring remains necessary to evaluate actual phthalate exposure levels and their potential risk in the Taiwanese population.

Growing evidence has indicated some endocrine-related effects of phthalates on human health [5], especially in the thyroid and reproductive glands [6]. Some studies have revealed that phthalates may decrease thyroid and growth hormones in different races [7–10]. Other studies have revealed concerns related to phthalate exposure effects on pediatric allergy diseases [11–12] and adult infertility [13–15]. Some studies have indicated that several factors, such as age, gender, or lifestyle, may affect the exposure levels of phthalates [16–18] and influence their effects on the health of different populations.

A well-organized human biomonitoring study is useful for determining the exposure dose in the general population and assessing exposure, risk, and management of complications [19]. Some studies, including the German Environmental Survey (GerEs) [19] and National Health and Nutrition Survey (NHANES) [2], have demonstrated the time-trend variation and potential influence of environmental chemicals in the general population. Recent studies, such as the Canadian Health Measures Survey (CHMS) [20], Korean Environmental Health Survey (KEHS) [21], Consortium to Perform Human Biomonitoring on a European Scale (COPHES) and DEMOCOPHES study [22], Belgium (FLEHS) [23] and Danish studies [24], have revealed exposure profiles of populations affected by environmental chemicals differ according to countries, lifestyles, and exposure sources. We aimed to conduct an exposure assessment study of phthalates, a part of the Taiwan Environmental Surveys for Toxicants (TESTs), using biosamples from a general population in Taiwan and evaluating the effects of relevant factors such as demographic characteristics and lifestyle on phthalate exposure.

Materials and Methods

Ethics statement

This study was approved by Research Ethics Committee, National Health Research Institutes (No. EC1020206) in Taiwan. Written informed consent from each participant and additional signatures from their parents for minors was obtained prior to study enrollment.

Subject recruitment and data collection

In order to obtain sufficient participation from the general Taiwanese population, we collaborated with the National and Nutrition Health Survey in Taiwan (NAHSIT) team and used the same sampling frame and procedure in subject recruitment [25]. There are five major regions and 22 cities/ counties in Taiwan (Fig 1). Briefly, NAHSIT selected twenty major cities/ counties of Taiwan and selected subjects in all age groups. According to the population density and urbanization of each city in Taiwan, each city township is classified into two groups. Then, NAHSIT randomly selected two townships of each group to represent a city/ county. Subjects had to be Taiwanese ≥7 years old, and excluded pregnant and breast-feeding women, individuals with severe disease (e.g. cancer patients), foreigners, and citizens in hospitals and jails [25]. We selected seventeen townships of eleven cities/ counties in the northern region (ex.: Taipei and New Taipei City), central region (ex.: Taichung and Chia-Yi City), southern region (ex.: Kaohsiung City), eastern region (ex.: Hua-Lien County), and the remote island region (Peng-Hu County) of Taiwan (Fig 1) during a time period from May to December 2013. We interviewed a total of 500 subjects on the day of health examination at community center or elementary school; 394 subjects participated in this study, which yielded a response rate around 78%. Most of the subjects who refused participation were children afraid to provide samples.

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Fig 1. Eleven sampling sites of the TEST study in Taiwan.

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After informed consent was obtained, first morning urine samples (20 mL) were collected using a PP container and transferred into an acetonitrile (ACN)-prewashed amber glass bottle and stored at -20 ℃. An interview questionnaire was also used to obtain information about participant demographics (age, gender, residence, education), environmental exposure (cigarette smoking, pesticide usage), lifestyles (plastics product usage, personal care products), and other related factors (disease history).

Phthalate metabolite analysis

Eleven phthalate metabolites including mono-ethylhexyl phthalate (MEHP), mono-(2-ethyl-5-oxo-hexyl) phthalate (MEOHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP), mono-(2-carboxymethylhexyl) phthalate (MCMHP), mono-n-butyl phthalate (MnBP), mono-iso-butyl phthalate (MiBP), mono-ethyl phthalate (MEP), mono-iso-nonyl phthalate (MiNP), mono-benzyl phthalate (MBzP) and mono-methyl phthalate (MMP) representing exposure to seven commonly used phthalates (DEHP, DnBP, DiBP, DEP, di-iso-nonyl phthalate (DiNP), benzyl butyl phthalates (BBzP) and dimethyl phthalate (DMP) were measured in each urine sample. We used a modified method previously described by Koch et al. [26] using on-line chromatography to increase the efficiency and accuracy of analysis. After a urine sample was thawed and sonicated for 10–15 min, the urine sample (100 μl) was loaded into a glass vial (2 ml) which contained ammonium acetate (AA, 20 μl, >98%, Sigma Aldrich Lab., Inc., St. Louis, MO, USA), β-glucuronidase (10 μl, E.coli K12, Roche Biomedical, Mannheim, Germany), and a mixture of ten isotopic (¹³C₄) phthalate metabolite standards (100 μl. Cambridge Isotope Lab., Inc., Andover, MA, USA). After the sample was incubated (37℃, 90 min), a 270 μl solution (5% ACN), Merck, Darmstadt, Germany) with 0.1% formic acid (FA, Merck, Darmstadt, Germany) was added and sealed with the PTEF cap for analysis. We used an on-line system which was coupled with liquid chromatography/electrospray tandem mass spectrometry (LC–ESI-MS/MS) (Agilent 1200/ API 4000, Applied Biosystems, Foster City, CA, USA). We used two columns in our on-line system. One C18 column (Inertsil ODS-3, 33×4.6 mm, 5 μm, GL Science, Tokyo, Japan) was used to extract and clean our sample, and an analytical column (Inertsil Ph, 150 *4.6 mm, 5 μm, GL Science, Tokyo, Japan) was used to separate different phthalate metabolites. The gradient program of the clean-up column was listed as follows: 100% solution A (5% ACN + 0.1% FA) (0–7 min), 100% solution B (90% ACN + 0.1% FA) (7–9 min), 100% solution A (9–10 min) and continued to 12 min. The flow rate was set at 1000 μl/min. The analytical column gradient program was listed as follows: 100% solution C (50% ACN + 10 mmole AA) (0–3.6 min), 100% solution D (95% ACN + 10 mmole AA) (3.6–8.6 min), 100% solution C (8.6–9 min) and continued to 12 min. We used a negative multiple reaction monitoring model for mass spectroscopy detection. The ion pair of each phthalate metabolites was listed as follows: MEHP (277/134), MEOHP (291/143), MEHHP (293/121), MECPP (307/159), MCMHP (307/113), MnBP (221/71), MiBP (221/71), MEP (193/121), MiNP (291/121), MBzP (255/183), and MMP (179/107). The detection limits of MEHP, MEOHP, MEHHP, MECPP, MCMHP, MnBP, MiBP, MEP, MiNP, MBzP, and MMP were 0.7, 0.3, 0.3, 0.3, 0.1, 1, 1, 0.3, 0.1, 0.3 and 0.3 ng/mL respectively. One blank, repeat, and quality control (QC) sample were included in each batch of analyzed samples. The concentration of blank samples shall be below two times the detection limit. The QC sample was spiked in a pooled urine sample with a mixture of phthalate metabolite standards (20–50 ng/ml) in each sample. The relative percent difference of repeat sample and recovery of QC sample shall be within ± 30%. Urinary creatinine levels were measured by spectrophotometric methods, with picric acid as a reactive compound for reading at 520 nm measurement (Beckman; DXC 800).

Statistical Analysis

Levels of urinary phthalate metabolites and creatinine were evaluated as continuous variables. Meanwhile, age, gender, residence, education, family income, cigarette smoking and beverage status (tea, coffee, alcohol), as well as the frequency of plastic products, personal care products, and pesticide use were evaluated as nominal variables. All measured phthalate metabolites were logarithmically (log₁₀) transformed for Pearson correlation analysis. We categorized our subjects into adults (≧18 years old) and minors (<18 years old), and further stratified four comparatively sized age groups: ≧7~<18 years old, ≧18~<40 years old, ≧40~<65 years old, ≧65 years old (elders). The Mann-Whitney U test, Chi-square test, and Kruskal-Wallis test were used to evaluate differences between demographic data, such as age and gender, region, and each level of phthalate metabolites for continuous and categorical variables, respectively. We calculated not detectable (ND) levels, below the detection limit, as 1/2 detection limit of each phthalate metabolite, and detectable rate as number of urine sample with level of each phthalate metabolite above detection limit divided by all analyzed urine samples. We presented our data both in a creatinine-based level, which adjusted for individual urinary excretion rate, and creatinine-unadjusted level in the parentheses. Pearson correlation coefficients assessed correlations between age and each urinary phthalate metabolite level. Commercially available statistical software (SPSS version 22.0; SAS Institute, Cary, NC, USA) was used for all statistical analysis. The level of significance was set at P< 0.05.

Results

Characteristics of Subjects

A total of 296 adults and 98 minors with completed data were included for statistical analysis in this study. In adults, most participants were between 40–65 years of age (44%), married (72.9%), well-educated (56.8%), middle-class status (57%), non-smokers (74.3%), and reported no pesticide use at home (74.7%); around half were tea and coffee drinkers (57.4% and 42.9%, respectively). A high percentage of participants did not drink alcohol (85.8%) or chew betel nuts (93.2%). For minors, around half of them were boys (55%), below 12 years old (52%); half of them reported as tea drinkers and passive smokers. The detailed demographic characteristics of all participants were shown in Table 1.

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Table 1. Demographic characteristics of all participants in this study (N = 394).

https://doi.org/10.1371/journal.pone.0133782.t001

Levels of eleven phthalate metabolites

Fig 2 and Table 2 (un-adjusted data was shown in the parentheses of Table 2) showed the distribution and creatinine-adjusted concentrations of eleven phthalate metabolites in our participants classified by age and gender, respectively. For adults, the median levels of MEHHP (women/ men: 24.1 vs. 18.3 μg/g-c, P = 0.011), MECPP (28.3 vs. 24.4 μg/g-c, P = 0.010), MnBP (22.1 vs. 13.8 μg/g-c, P = 0.001), MEP (19.6 vs. 10.4 μg/g creatinine [μg/g-c], P<0.001), MBzP (0.3 vs. 0.2 μg/g-c, P<0.001), MiNP (0.3 vs. 0.2 μg/g-c, P<0.001) in women (≧18 year old, n = 156) were significantly higher than those seen in men (≧18 year old, n = 134). For minors, the median levels of most phthalate metabolites in boys (n = 54) was higher than those in girls (n = 43), but no statistical significance was observed. We found that the median levels of MEOHP, MEHHP, MECPP, MnBP, MiBP and MMP in minors were higher than those seen in adults.

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Table 2. Distribution of creatinine-adjusted levels (μg/g creatinine or ng/ml) of phthalate metabolites ^{^a} in a sample of the general Taiwanese population (N = 387) by minors and adults.

https://doi.org/10.1371/journal.pone.0133782.t002

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Fig 2. Distribution of 11 phthalate metabolites in a sample of the general Taiwanese population (N = 387) ≥7 years of age.

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Fig 3 showed the distribution and median levels of phthalate metabolites in our sample of the general Taiwanese population classified into four age groups. We found that J-shape curves of the exposure levels of MEOHP (P<0.001), MECPP(P = 0.002), MnBP (P = 0.044), MiNP (P<0.001), MBzP (P<0.001) and MMP (P<0.001) in our subjects were significantly varied by age regardless of gender, which indicated minors may expose to higher level of these phthalates than adults. The median level of MEP (creatinine-unadjusted) at age 18–40 years was significantly (P<0.001) higher than the other age groups, especially for women. Besides, median levels of MnBP and MiBP in all subjects decreased along with increasing age. No significant change of MEHP in our subjects was observed regardless of age or gender. Detailed data were shown in the S2 Table.

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Fig 3. Distribution of 11 phthalate metabolites in a sample of the general Taiwanese population (N = 387) by age groups (solid line inside the box plot: median).

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We further categorized our subjects according to five regions (S3 Table). We found that the median levels of MEHP, MEHHP, MEOHP, MECPP, MCMHP, MiBP, MEP, MBzP, and MMP were statistically significant (p<0.001) varied by region. Except for the remote island region, we observed that the median levels of MEHP, MECPP, MCMHP, MnBP, MiBP and MBzP in southern Taiwan were highest among four regions. We also observed a 2-3-fold higher median level of MMP in the remote island was higher than other regions. The median levels of MiNP and MBzP in all areas were below the detection limit.

Comparison of phthalate exposure among different countries

Fig 4 showed a comparison of phthalate metabolite levels in the general population between Taiwan, Canada [20], and the United States [27]. We found that the geometric mean (GM) level of MEHP in the Taiwanese population sample was 1.6-fold higher than those in the NHANES 10–11. The GM levels of secondary MEHP metabolites and MnBP in this study were comparable to those reported in the CHMS 07–08 and NHANES 10–11. The exposure levels of MEP and MBzP were approximately 5–7 times lower than those in CHMS 07–08 and NHANES 10–11.

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Fig 4. Comparison of urinary levels of seven phthalate metabolites in a general population sample of Taiwanese (≧7 years), Americans (>6 years) and Canadians (18–49 years).

https://doi.org/10.1371/journal.pone.0133782.g004

Discussion

This is the first study systematically evaluating phthalate exposure in a sample of the general Taiwanese population. We found a significant difference in phthalate exposure according to age and gender. Minors (≧7~<18 years old) and elders (≧ 65 years old) tended to have exposure to higher levels of most phthalates, such as DEHP, DnBP, BBzP and DMP. Women (≧18 years old) were exposed to higher levels of DEHP, DBP (in particular DnBP) and DEP than men (≧18 years old) in Taiwan. Minors had significantly higher urinary levels of MEHHP, MEOHP, MECPP, MnBP and MiBP than the adult population, especially for boys.

High detectable rates (>70%) of MEHP, MEOHP, MEHHP, MECPP, MnBP, MiBP, MEP and MMP were observed in this sample of the general Taiwanese population. Due to the short-half-lives of most phthalates, DEHP, DnBP, DiBP, DEP, and DMP are frequently present in the daily life of the general Taiwanese population. Over 73% of participating adults and minors frequently used food preservation film and plastic bag for food storage (S4 Table). About 73% and 43% of minors and adults, respectively, used body wash every day, whereas less than 2% of all participants frequently used perfume and nail polish; these results were not consistent with other studies [28–29]. Around 42% and 13% of minors and adults, respectively, took at least one medicine constantly during the past one month. About 25% of participants reported using pesticides at home. Plastic products related to food preservation, body wash, medicine, and pesticide usage were potential sources of different phthalates exposure in the general Taiwanese population.

A low detection rate of MiNP (11.1%) and MBzP (22.4%) in Taiwanese was observed regardless of different age groups and gender. Although DINP is a substitute for DEHP in plastics, DINP is not widely used for plastics related to products used daily in Taiwan or other Asian countries. Besides, MiNP is not the major DINP metabolite as it is converted into secondary metabolites [30]. Thus, the low MiNP detection rate does not imply low DINP exposure in the general Taiwanese population. It is also important to note that new plastic phthalate substitutes have been developed; their use may increase rapidly in the near future [31]. Monitoring secondary metabolites of DINP is worthy of further investigation in studies of Asian countries. BBzP is primarily used in PVC-based floor materials, which are not used as much for Taiwanese home decoration as in previous years. Due to MBzP being a major metabolite of BBzP, low detection of MBzP suggests low-exposure levels of BBzP in the general Taiwanese population.

We analyzed the difference of creatinine levels in our subjects by age and gender (S5 Table). We found that male subjects had a significantly higher median level of creatinine than females (102.4 vs. 71 mg/dl, p<0.001) regardless of age difference. We further excluded 24 subjects with creatinine<30 or ≧300 mg/dl for further analysis, and the results were consistent. Our study revealed that we may partially diminish the difference of phthalate exposure between males and females when using a creatinine-adjustment-based method for comparison. However, we found a significantly high correlation (R = 0.83~0.96, P<0.001, S6 Table) between creatinine-adjusted and unadjusted concentrations of each phthalate metabolites using Pearson correlation analysis. Hence, in order to adjust for individual urinary excretion rate, we primarily presented our data in a creatinine-based level.

We found that urinary levels of DEHP metabolites in minor Taiwanese boys were significantly higher than those of most adult age groups. For minors, the behaviors of hand-to-mouth exposure and use of drinking containers are the likely causes of major phthalate exposure [32]. DEHP is of great concern in boys due to its antiandrogenic effects [33]; hence, intervention strategies for reducing phthalate exposure in boys warrant further investigation. Besides, we observed that urinary MECPP and ΣDEHP metabolites levels in elderly Taiwanese women (≧65 years) were higher than in any other age group. Taiwanese elderly women use food preservation films to save leftover food heated in a microwave oven; some food preservation films are made with PVC, which may increase DEHP concentration in meals [34]. Another possibility is that increased phthalate levels may correlate with increased amounts of cosmetic, perfume, and personal care product usage [28–29] in women. Only 45% of female adults frequently used lotion and body wash every day, whereas less than 5% of them used perfume and nail polish frequently (S4 Table). We suggested that food preservation and personal care products are possible sources of DEHP exposure in elderly Taiwanese women.

One study reported that GM levels of urinary MEHP, MEHHP, MEOHP, MEP, MBP were around 9.87, 50.9, 24.1, 19.8 and 55.9 μg/g creatinine, respectively, in adult Taiwanese during 2005–08 [35], two times higher than those in the current study. However, no information was available about potential phthalate exposure sources in the Taiwanese study from 2005–08. Another study also reported median level of urinary MEHP was 29.8 μg/g creatinine in 225 school children of Taipei city during 2009–10, four times higher than those in the current study [36]. Our sample of the general Taiwanese population provided some evidence of decreasing DEHP and DBP levels after enacted restrictions and regulations. In adult Taiwanese women, the median levels of most phthalate metabolites in age groups between 18 to 65 years were higher than those in men. For reproductive age women (18–40 years), some studies reported DEHP and DBP exposure in pregnant women may alter human hormones [37–38], fetal and child development [39–40], and pregnancy losses [41], endometriosis [42] or leiomyoma [43–44]. Although limited evidence showed that exposure levels of most phthalate metabolites significantly decreased after enacted restrictions and regulation [10], DEHP exposure levels in reproductive-aged Taiwanese women remain higher than those reported from other countries, warranting further investigation.

We found that both children and adolescents are exposed to higher levels of phthalates, a finding consistent with other studies [20, 23, 27, 43–44]. The Canadian study reported children had significantly higher urinary concentrations of metabolites of DEHP, DnBP and BBzP than adolescents and adults [20]; similar results were also observed in German and NHANES studies [27,44]. Increasing numbers of studies have reported endocrine, immunologic, and neurological effects of both prenatal and postnatal phthalates exposure in young children [11–12, 16–17, 40, 45]. Hence, regulating human biomonitoring value and intervention strategies of consumer behavior [32, 46] were necessary to reduce phthalate exposure in children.

Some studies revealed good correlations with primary and secondary DEHP metabolites in US and German populations [30, 44]. In adults, we observed a significantly low correlation between MEHP and three secondary DEHP metabolites (S6 Table), whereas we found moderate correlation between MEHHP and MECPP (R = 0.562, P<0.001) as well as MEOHP and MCMHP (R = 0.509, P<0.001). Our data showed a high correlation between MEHHP and ΣDEHP metabolites (R = 0.802, P<0.001), which indicated a good surrogate exposure index of DEHP in the Taiwanese population. In minors, we found a high correlation among MEOHP (R = 0.802, P<0.001), MEHHP (R = 0.782, P<0.001), MECPP, and ΣDEHP metabolites (S6 Table). Although metabolic abilities may differentiate between age groups, we suggested MEHHP could be a good biomarker of DEHP in the general Taiwanese population.

Our current study demonstrates several strengths. First, our study was a nationwide sample of subjects, including children ≥7 years old. Second, we also collected relevant factors from our participants through interview questionnaires, allowing further analysis of potential sources of phthalate exposure. Third, we determined the internal exposure in the general population which supplied a basis for estimating phthalate-related health risks. Our data provided reference values of phthalates in the Taiwanese population.

Some limitations of our study should be noticed in relation to data interpretation. First, this is a cross-sectional study with one-time measurements. The distribution of individual phthalate exposure can vary, and therefore further study is needed for temporal assessment over time. Second, we did not have sufficient evidence to link decreased phthalate exposure to this episodes. But, enacted restrictions and regulations on phthalates can possibly decrease phthalate exposure levels from many products in the general population.

We concluded that exposure levels of phthalates varied by age and gender, and were possibly affected by different lifestyles. Enacted restrictions and regulations could effectively reduce phthalate exposure in the general population; however, continuous biomonitoring surveillance is necessary to detect the long-term level variation. Although the DEHP exposure profile dramatically dropped after strict regulation, young boys and women in Taiwan were still exposed to higher levels of certain phthalates. These related health influences, such as reproductive development, are worthy of further investigation.

Supporting Information

S1 Table. Main phthalate products and urinary metabolites investigated in this study.

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(DOCX)

S2 Table. Detectable rate and distribution of creatinine-adjusted levels (μg/g creatinine, or ng/ml) of phthalate metabolites ^a in a sample of the general Taiwanese population (N = 387) by age groups.

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(DOCX)

S3 Table. Distribution of creatinine-adjusted levels (μg/g creatinine or ng/ml) in phthalate metabolites ^a from a sample of the general Taiwanese population by different regions (N = 387).

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(DOCX)

S4 Table. Number ^a of individuals who use phthalate-containing food-related plastic products, cosmetic and personal care products, medicine and pesticides.

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(DOCX)

S5 Table. Differences in subject creatinine levels (mg/dl) by age and gender (N = 387) in our study.

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(DOCX)

S6 Table. Pearson correlation coefficients among 11 urinary phthalate metabolites (creatinine-adjusted) in Taiwanese minors (n = 97, upper right) and Taiwanese adults (n = 290, age≧18 years old, lower left), and adjusted/unadjusted creatinine levels (diagonal) for all subjects.

https://doi.org/10.1371/journal.pone.0133782.s006

(DOCX)

Acknowledgments

We thank to our colleagues, Ms. Hsin-Ping Chiu and Ms. Hsin-Mei Lo at the National Health Research Institutes, for their assistance in data and specimen collection, and Mr. Chien-Jen Wang for his assistance in LC-MS/MS analysis. We also deeply grateful to the research assistants of the NAHSIT team, Mr. Zheng Chen and others, for their assistance and collaboration, and support of sampling by Health Promotion Administration, Ministry of Health and Welfare, Taiwan.

Author Contributions

Conceived and designed the experiments: PCH HCC WHP. Performed the experiments: WYL SSL. Analyzed the data: CHT. Contributed reagents/materials/analysis tools: PCH. Wrote the paper: PCH. Specimen collections, sample arrangement and preparations: WYL. Contributed to critical revision of the manuscript: PCH WHP HCC.

References

1. Schettler T. Human exposure to phthalates via consumer products. Int J Androl 2006;29:134–9. pmid:16466533
- View Article
- PubMed/NCBI
- Google Scholar
2. Zota AR, Calafat AM, Woodruff TJ. Temporal trends in phthalate exposures: findings from the National Health and Nutrition Examination Survey, 2001–2010. Environ Health Perspect. 2014;122: 235–41. pmid:24425099
- View Article
- PubMed/NCBI
- Google Scholar
3. Wu MT, Wu CF, Wu JR, Chen BH, Chen EK, Chao MC, et al. The public health threat of phthalate-tainted foodstuffs in Taiwan: the policies the government implemented and the lessons we learned. Environ Int. 2012;44:75–9. pmid:22361240
- View Article
- PubMed/NCBI
- Google Scholar
4. Li JH, Ko YC. Plasticizer incident and its health effects in Taiwan. Kaohsiung J Med Sci. 2012; 28(7 Suppl):S17–21. pmid:22871596
- View Article
- PubMed/NCBI
- Google Scholar
5. Huang PC, Liou SH, Ho IK, Chiang HC, Huang HI, Wang SL. Phthalates Exposure and Endocrinal Effects: An Epidemiological Review. J Food Drug Anal. 2012; 20: 719–33.
- View Article
- Google Scholar
6. Jurewicz J, Hanke W. Exposure to phthalates: reproductive outcome and children health. A review of epidemiological studies. Int J Occup Med Environ Health. 2011; 24: 115–41. pmid:21594692
- View Article
- PubMed/NCBI
- Google Scholar
7. Meeker JD, Ferguson KK. Relationship between urinary phthalate and bisphenol A concentrations and serum thyroid measures in U.S. adults and adolescents from the National Health and Nutrition Examination Survey (NHANES) 2007–2008. Environ Health Perspect. 2011;119:1396–402. pmid:21749963
- View Article
- PubMed/NCBI
- Google Scholar
8. Huang PC, Kuo PL, Chou YY, Lin SJ, Lee CC. Associations between Urinary Phthalate Monoesters and Thyroid Hormones in Pregnant Women. Hum Reprod. 2007; 22: 2715–22. pmid:17704099
- View Article
- PubMed/NCBI
- Google Scholar
9. Boas M, Frederiksen H, Feldt-Rasmussen U, Skakkebæk NE, Hegedüs L, Hilsted L, et al. Childhood exposure to phthalates: associations with thyroid function, insulin-like growth factor I, and growth. Environ Health Perspect. 2010;118:1458–64. pmid:20621847
- View Article
- PubMed/NCBI
- Google Scholar
10. Wu MT, Wu CF, Chen BH, Chen EK, Chen YL, Shiea J, et al. Intake of phthalate-tainted foods alters thyroid functions in Taiwanese children. PLoS One. 2013; 8: e55005. pmid:23383031
- View Article
- PubMed/NCBI
- Google Scholar
11. Ku HY, Su PH, Wen HJ, Sun HL, Wang CJ, Chen HY, et al. Prenatal and postnatal exposure to phthalate esters and asthma: a 9-year follow-up study of a Taiwanese birth cohort. PLoS One. 2015; 10: e0123309. pmid:25875379
- View Article
- PubMed/NCBI
- Google Scholar
12. Wang IJ, Lin CC, Lin YJ, Hsieh WS, Chen PC. Early life phthalate exposure and atopic disorders in children: a prospective birth cohort study. Environ Int. 2014; 62: 48–54. pmid:24161446
- View Article
- PubMed/NCBI
- Google Scholar
13. Huang PC, Tsai EM, Li WF, Liao PC, Chung MC, Wang YH, et al. Association between Phthalate Exposure and Glutathione S-transferase (GST) M1 Polymorphism in Adenomyosis, Leiomyoma, and Endometriosis. Hum Reprod. 2010; 25: 986–94. pmid:20147336
- View Article
- PubMed/NCBI
- Google Scholar
14. Mendiola J, Meeker JD, Jørgensen N, Andersson AM, Liu F, Calafat AM, et al. Urinary concentrations of di(2-ethylhexyl) phthalate metabolites and serum reproductive hormones: pooled analysis of fertile and infertile men. J Androl. 2012; 33: 488–98. pmid:21597090
- View Article
- PubMed/NCBI
- Google Scholar
15. Huang PC, Li WF, Liao PC, Sun CW, Tsai EM, Wang SL. Risk for estrogen-dependent diseases in relation to phthalate exposure and polymorphisms of CYP17A1 and estrogen receptor genes. Environ Sci Pollut Res Int. 2014; 21: 13964–73. pmid:25030786
- View Article
- PubMed/NCBI
- Google Scholar
16. Zhang Y, Meng X, Chen L, Li D, Zhao L, Zhao Y, et al. Age and sex-specific relationships between phthalate exposures and obesity in Chinese children at puberty. PLoS One. 2014; 9: e104852. pmid:25121758
- View Article
- PubMed/NCBI
- Google Scholar
17. Smerieri A, Testa C, Lazzeroni P, Nuti F, Grossi E, Cesari S, et al. Di-(2-ethylhexyl) phthalate metabolites in urine show age-related changes and associations with adiposity and parameters of insulin sensitivity in childhood. PLoS One. 2015; 10: e0117831. pmid:25706863
- View Article
- PubMed/NCBI
- Google Scholar
18. Bai PY, Wittert GA, Taylor AW, Martin SA, Milne RW, Shi Z. The association of socio-demographic status, lifestyle factors and dietary patterns with total urinary phthalates in Australian men. PLoS One. 2015; 10: e0122140. pmid:25875472
- View Article
- PubMed/NCBI
- Google Scholar
19. Becker K, Seiwert M, Casteleyn L, Joas R, Joas A, Biot P, et al. A systematic approach for designing a HBM pilot study for Europe. Int J Hyg Environ Health. 2014; 217: 312–22. pmid:23928002
- View Article
- PubMed/NCBI
- Google Scholar
20. Saravanabhavan G, Guay M, Langlois É, Giroux S, Murray J, Haines D. Biomonitoring of phthalate metabolites in the Canadian population through the Canadian Health Measures Survey (2007–2009). Int J Hyg Environ Health. 2013; 216: 652–61. pmid:23419587
- View Article
- PubMed/NCBI
- Google Scholar
21. Ha M, Kwon HJ, Leem JH, Kim HC, Lee KJ, Park I, et al. Korean Environmental Health Survey in Children and Adolescents (KorEHS-C): survey design and pilot study results on selected exposure biomarkers. Int J Hyg Environ Health. 2014; 217: 260–70. pmid:23831304
- View Article
- PubMed/NCBI
- Google Scholar
22. Schindler BK, Esteban M, Koch HM, Castano A, Koslitz S, Cañas A, et al. The European COPHES/DEMOCOPHES project: towards transnational comparability and reliability of human biomonitoring results. Int J Hyg Environ Health. 2014; 217: 653–61. pmid:24405937
- View Article
- PubMed/NCBI
- Google Scholar
23. Dewalque L, Pirard C, Charlier C. Measurement of urinary biomarkers of parabens, benzophenone-3, and phthalates in a Belgian population. Biomed Res Int. 2014; 2014: 649314. pmid:24719881
- View Article
- PubMed/NCBI
- Google Scholar
24. Frederiksen H, Jensen TK, Jørgensen N, Kyhl HB, Husby S, Skakkebæk NE, et al. Human urinary excretion of non-persistent environmental chemicals: an overview of Danish data collected between 2006 and 2012. Reproduction. 2014; 147: 555–65. pmid:24395915
- View Article
- PubMed/NCBI
- Google Scholar
25. Pan WH, Wu HJ, Yeh CJ, Chuang SY, Chang HY, Yeh NH, et al. Diet and health trends in Taiwan: comparison of two nutrition and health surveys from 1993–1996 and 2005–2008. Asia Pac J Clin Nutr. 2011; 20: 238–50. pmid:21669593
- View Article
- PubMed/NCBI
- Google Scholar
26. Koch HM, Gonzalez-Reche LM, Angerer J. On-line clean-up by multidimensional liquid chromatography-electrospray ionization tandem mass spectrometry for high throughput quantification of primary and secondary phthalate metabolites in human urine. J Chromatogr B Analyt Technol Biomed Life Sci. 2003; 784: 169–82. pmid:12504195
- View Article
- PubMed/NCBI
- Google Scholar
27. CDC 2012. Fourth national report on human exposure to environmental chemicals, updated tables. Available: http://www.cdc.gov/exposurereport/pdf/FourthReport_UpdatedTables _Feb2015.pdf. Accessed 2015 Feb 1.
28. Parlett LE, Calafat AM, Swan SH. Women's exposure to phthalates in relation to use of personal care products. J Expo Sci Environ Epidemiol. 2013; 23:197–206. pmid:23168567
- View Article
- PubMed/NCBI
- Google Scholar
29. Philippat C, Bennett D, Calafat AM, Picciotto IH. Exposure to select phthalates and phenols through use of personal care products among Californian adults and their children. Environ Res. 2015; 140: 369–76. pmid:25929801
- View Article
- PubMed/NCBI
- Google Scholar
30. Calafat AM, Wong LY, Silva MJ, Samandar E, Preau JL Jr, Jia LT, et al. Selecting adequate exposure biomarkers of diisononyl and diisodecyl phthalates: data from the 2005–2006 National Health and Nutrition Examination Survey. Environ Health Perspect. 2011; 119: 50–5. pmid:20870567
- View Article
- PubMed/NCBI
- Google Scholar
31. Schütze A, Kolossa-Gehring M, Apel P, Brüning T, Koch HM. Entering markets and bodies: increasing levels of the novel plasticizer Hexamoll DINCH in 24 h urine samples from the German Environmental Specimen Bank. Int J Hyg Environ Health. 2014; 217: 421–6. pmid:24029725
- View Article
- PubMed/NCBI
- Google Scholar
32. Chen CY, Chou YY, Lin SJ, Lee CC. Developing an intervention strategy to reduce phthalate exposure in Taiwanese girls. Sci Total Environ. 2015; 517: 125–131. pmid:25725197
- View Article
- PubMed/NCBI
- Google Scholar
33. Swan SH. Environmental phthalate exposure in relation to reproductive outcomes and other health endpoints in humans. Environ Res. 2008; 108: 177–84. pmid:18949837
- View Article
- PubMed/NCBI
- Google Scholar
34. Chen ML, Chen JS, Tang CL, Mao IF. The internal exposure of Taiwanese to phthalate—an evidence of intensive use of plastic materials. Environ Int. 2008; 34:79–85. pmid:17765308
- View Article
- PubMed/NCBI
- Google Scholar
35. Huang PC, Liou SH, Sun CW, Pan WH, Wang CJ, Wang SL. Human Biomonitoring for Phthalates Exposure from Nutrition and Health Survey in Taiwan (NAHSIT). International Society of Exposure Science conference, proceeding, Seattle, WA, USA; 2012.
36. Bao J, Zeng XW, Qin XD, Lee YL, Chen X, Jin YH, et al. Phthalate Metabolites in Urine Samples from School Children in Taipei, Taiwan. Arch Environ Contam Toxicol. 2015 Mar 8.
- View Article
- Google Scholar
37. Lin LC, Wang SL, Chang YC, Huang PC, Cheng JT, Su PH, et al. Associations between maternal phthalate exposure and cord sex hormones in human infants. Chemosphere. 2011; 83: 1192–9. pmid:21272909
- View Article
- PubMed/NCBI
- Google Scholar
38. Sathyanarayana S, Barrett E, Butts S, Wang C, Swan SH. Phthalate exposure and reproductive hormone concentrations in pregnancy. Reproduction. 2014; 147: 401–9. pmid:24196015
- View Article
- PubMed/NCBI
- Google Scholar
39. Swan SH, Sathyanarayana S, Barrett ES, Janssen S, Liu F, Nguyen RH, et al. First trimester phthalate exposure and anogenital distance in newborns. Hum Reprod. 2015; 30: 963–72. pmid:25697839
- View Article
- PubMed/NCBI
- Google Scholar
40. Kobrosly RW, Evans S, Miodovnik A, Barrett ES, Thurston SW, Calafat AM, et al. Prenatal phthalate exposures and neurobehavioral development scores in boys and girls at 6–10 years of age. Environ Health Perspect. 2014; 122: 521–8. pmid:24577876
- View Article
- PubMed/NCBI
- Google Scholar
41. Toft G, Jönsson BA, Lindh CH, Jensen TK, Hjollund NH, Vested A, et al. Association between pregnancy loss and urinary phthalate levels around the time of conception. Environ Health Perspect. 2012; 120: 458–63. pmid:22113848
- View Article
- PubMed/NCBI
- Google Scholar
42. Reddy BS, Rozati R, Reddy BV, Raman NV. Association of phthalate esters with endometriosis in Indian women. BJOG. 2006; 113: 515–20. pmid:16637895
- View Article
- PubMed/NCBI
- Google Scholar
43. Becker K, Göen T, Seiwert M, Conrad A, Pick-Fuss H, Müller J, et al. GerES IV: phthalate metabolites and bisphenol A in urine of German children. Int J Hyg Environ Health. 2009; 212: 685–92. pmid:19729343
- View Article
- PubMed/NCBI
- Google Scholar
44. Koch HM, Wittassek M, Brüning T, Angerer J, Heudorf U. Exposure to phthalates in 5–6 years old primary school starters in Germany—a human biomonitoring study and a cumulative risk assessment. Int J Hyg Environ Health. 2011; 214: 188–95. pmid:21371937
- View Article
- PubMed/NCBI
- Google Scholar
45. Téllez-Rojo MM, Cantoral A, Cantonwine DE, Schnaas L, Peterson K, Hu H, et al. Prenatal urinary phthalate metabolites levels and neurodevelopment in children at two and three years of age. Sci Total Environ. 2013; 461–462: 386–90. pmid:23747553
- View Article
- PubMed/NCBI
- Google Scholar
46. Schulz C, Wilhelm M, Heudorf U, Kolossa-Gehring M, Human Biomonitoring Commission of the German Federal Environment Agency. Update of the reference and HBM values derived by the German Human Biomonitoring Commission. Int J Hyg Environ Health. 2011; 215: 26–35.
- View Article
- Google Scholar

[ref1] 1. Schettler T. Human exposure to phthalates via consumer products. Int J Androl 2006;29:134–9. pmid:16466533
View Article
PubMed/NCBI
Google Scholar

[2] View Article

[3] PubMed/NCBI

[4] Google Scholar

[ref2] 2. Zota AR, Calafat AM, Woodruff TJ. Temporal trends in phthalate exposures: findings from the National Health and Nutrition Examination Survey, 2001–2010. Environ Health Perspect. 2014;122: 235–41. pmid:24425099
View Article
PubMed/NCBI
Google Scholar

[6] View Article

[7] PubMed/NCBI

[8] Google Scholar

[ref3] 3. Wu MT, Wu CF, Wu JR, Chen BH, Chen EK, Chao MC, et al. The public health threat of phthalate-tainted foodstuffs in Taiwan: the policies the government implemented and the lessons we learned. Environ Int. 2012;44:75–9. pmid:22361240
View Article
PubMed/NCBI
Google Scholar

[10] View Article

[11] PubMed/NCBI

[12] Google Scholar

[ref4] 4. Li JH, Ko YC. Plasticizer incident and its health effects in Taiwan. Kaohsiung J Med Sci. 2012; 28(7 Suppl):S17–21. pmid:22871596
View Article
PubMed/NCBI
Google Scholar

[14] View Article

[15] PubMed/NCBI

[16] Google Scholar

[ref5] 5. Huang PC, Liou SH, Ho IK, Chiang HC, Huang HI, Wang SL. Phthalates Exposure and Endocrinal Effects: An Epidemiological Review. J Food Drug Anal. 2012; 20: 719–33.
View Article
Google Scholar

[18] View Article

[19] Google Scholar

[ref6] 6. Jurewicz J, Hanke W. Exposure to phthalates: reproductive outcome and children health. A review of epidemiological studies. Int J Occup Med Environ Health. 2011; 24: 115–41. pmid:21594692
View Article
PubMed/NCBI
Google Scholar

[21] View Article

[22] PubMed/NCBI

[23] Google Scholar

[ref7] 7. Meeker JD, Ferguson KK. Relationship between urinary phthalate and bisphenol A concentrations and serum thyroid measures in U.S. adults and adolescents from the National Health and Nutrition Examination Survey (NHANES) 2007–2008. Environ Health Perspect. 2011;119:1396–402. pmid:21749963
View Article
PubMed/NCBI
Google Scholar

[25] View Article

[26] PubMed/NCBI

[27] Google Scholar

[ref8] 8. Huang PC, Kuo PL, Chou YY, Lin SJ, Lee CC. Associations between Urinary Phthalate Monoesters and Thyroid Hormones in Pregnant Women. Hum Reprod. 2007; 22: 2715–22. pmid:17704099
View Article
PubMed/NCBI
Google Scholar

[29] View Article

[30] PubMed/NCBI

[31] Google Scholar

[ref9] 9. Boas M, Frederiksen H, Feldt-Rasmussen U, Skakkebæk NE, Hegedüs L, Hilsted L, et al. Childhood exposure to phthalates: associations with thyroid function, insulin-like growth factor I, and growth. Environ Health Perspect. 2010;118:1458–64. pmid:20621847
View Article
PubMed/NCBI
Google Scholar

[33] View Article

[34] PubMed/NCBI

[35] Google Scholar

[ref10] 10. Wu MT, Wu CF, Chen BH, Chen EK, Chen YL, Shiea J, et al. Intake of phthalate-tainted foods alters thyroid functions in Taiwanese children. PLoS One. 2013; 8: e55005. pmid:23383031
View Article
PubMed/NCBI
Google Scholar

[37] View Article

[38] PubMed/NCBI

[39] Google Scholar

[ref11] 11. Ku HY, Su PH, Wen HJ, Sun HL, Wang CJ, Chen HY, et al. Prenatal and postnatal exposure to phthalate esters and asthma: a 9-year follow-up study of a Taiwanese birth cohort. PLoS One. 2015; 10: e0123309. pmid:25875379
View Article
PubMed/NCBI
Google Scholar

[41] View Article

[42] PubMed/NCBI

[43] Google Scholar

[ref12] 12. Wang IJ, Lin CC, Lin YJ, Hsieh WS, Chen PC. Early life phthalate exposure and atopic disorders in children: a prospective birth cohort study. Environ Int. 2014; 62: 48–54. pmid:24161446
View Article
PubMed/NCBI
Google Scholar

[45] View Article

[46] PubMed/NCBI

[47] Google Scholar

[ref13] 13. Huang PC, Tsai EM, Li WF, Liao PC, Chung MC, Wang YH, et al. Association between Phthalate Exposure and Glutathione S-transferase (GST) M1 Polymorphism in Adenomyosis, Leiomyoma, and Endometriosis. Hum Reprod. 2010; 25: 986–94. pmid:20147336
View Article
PubMed/NCBI
Google Scholar

[49] View Article

[50] PubMed/NCBI

[51] Google Scholar

[ref14] 14. Mendiola J, Meeker JD, Jørgensen N, Andersson AM, Liu F, Calafat AM, et al. Urinary concentrations of di(2-ethylhexyl) phthalate metabolites and serum reproductive hormones: pooled analysis of fertile and infertile men. J Androl. 2012; 33: 488–98. pmid:21597090
View Article
PubMed/NCBI
Google Scholar

[53] View Article

[54] PubMed/NCBI

[55] Google Scholar

[ref15] 15. Huang PC, Li WF, Liao PC, Sun CW, Tsai EM, Wang SL. Risk for estrogen-dependent diseases in relation to phthalate exposure and polymorphisms of CYP17A1 and estrogen receptor genes. Environ Sci Pollut Res Int. 2014; 21: 13964–73. pmid:25030786
View Article
PubMed/NCBI
Google Scholar

[57] View Article

[58] PubMed/NCBI

[59] Google Scholar

[ref16] 16. Zhang Y, Meng X, Chen L, Li D, Zhao L, Zhao Y, et al. Age and sex-specific relationships between phthalate exposures and obesity in Chinese children at puberty. PLoS One. 2014; 9: e104852. pmid:25121758
View Article
PubMed/NCBI
Google Scholar

[61] View Article

[62] PubMed/NCBI

[63] Google Scholar

[ref17] 17. Smerieri A, Testa C, Lazzeroni P, Nuti F, Grossi E, Cesari S, et al. Di-(2-ethylhexyl) phthalate metabolites in urine show age-related changes and associations with adiposity and parameters of insulin sensitivity in childhood. PLoS One. 2015; 10: e0117831. pmid:25706863
View Article
PubMed/NCBI
Google Scholar

[65] View Article

[66] PubMed/NCBI

[67] Google Scholar

[ref18] 18. Bai PY, Wittert GA, Taylor AW, Martin SA, Milne RW, Shi Z. The association of socio-demographic status, lifestyle factors and dietary patterns with total urinary phthalates in Australian men. PLoS One. 2015; 10: e0122140. pmid:25875472
View Article
PubMed/NCBI
Google Scholar

[69] View Article

[70] PubMed/NCBI

[71] Google Scholar

[ref19] 19. Becker K, Seiwert M, Casteleyn L, Joas R, Joas A, Biot P, et al. A systematic approach for designing a HBM pilot study for Europe. Int J Hyg Environ Health. 2014; 217: 312–22. pmid:23928002
View Article
PubMed/NCBI
Google Scholar

[73] View Article

[74] PubMed/NCBI

[75] Google Scholar

[ref20] 20. Saravanabhavan G, Guay M, Langlois É, Giroux S, Murray J, Haines D. Biomonitoring of phthalate metabolites in the Canadian population through the Canadian Health Measures Survey (2007–2009). Int J Hyg Environ Health. 2013; 216: 652–61. pmid:23419587
View Article
PubMed/NCBI
Google Scholar

[77] View Article

[78] PubMed/NCBI

[79] Google Scholar

[ref21] 21. Ha M, Kwon HJ, Leem JH, Kim HC, Lee KJ, Park I, et al. Korean Environmental Health Survey in Children and Adolescents (KorEHS-C): survey design and pilot study results on selected exposure biomarkers. Int J Hyg Environ Health. 2014; 217: 260–70. pmid:23831304
View Article
PubMed/NCBI
Google Scholar

[81] View Article

[82] PubMed/NCBI

[83] Google Scholar

[ref22] 22. Schindler BK, Esteban M, Koch HM, Castano A, Koslitz S, Cañas A, et al. The European COPHES/DEMOCOPHES project: towards transnational comparability and reliability of human biomonitoring results. Int J Hyg Environ Health. 2014; 217: 653–61. pmid:24405937
View Article
PubMed/NCBI
Google Scholar

[85] View Article

[86] PubMed/NCBI

[87] Google Scholar

[ref23] 23. Dewalque L, Pirard C, Charlier C. Measurement of urinary biomarkers of parabens, benzophenone-3, and phthalates in a Belgian population. Biomed Res Int. 2014; 2014: 649314. pmid:24719881
View Article
PubMed/NCBI
Google Scholar

[89] View Article

[90] PubMed/NCBI

[91] Google Scholar

[ref24] 24. Frederiksen H, Jensen TK, Jørgensen N, Kyhl HB, Husby S, Skakkebæk NE, et al. Human urinary excretion of non-persistent environmental chemicals: an overview of Danish data collected between 2006 and 2012. Reproduction. 2014; 147: 555–65. pmid:24395915
View Article
PubMed/NCBI
Google Scholar

[93] View Article

[94] PubMed/NCBI

[95] Google Scholar

[ref25] 25. Pan WH, Wu HJ, Yeh CJ, Chuang SY, Chang HY, Yeh NH, et al. Diet and health trends in Taiwan: comparison of two nutrition and health surveys from 1993–1996 and 2005–2008. Asia Pac J Clin Nutr. 2011; 20: 238–50. pmid:21669593
View Article
PubMed/NCBI
Google Scholar

[97] View Article

[98] PubMed/NCBI

[99] Google Scholar

[ref26] 26. Koch HM, Gonzalez-Reche LM, Angerer J. On-line clean-up by multidimensional liquid chromatography-electrospray ionization tandem mass spectrometry for high throughput quantification of primary and secondary phthalate metabolites in human urine. J Chromatogr B Analyt Technol Biomed Life Sci. 2003; 784: 169–82. pmid:12504195
View Article
PubMed/NCBI
Google Scholar

[101] View Article

[102] PubMed/NCBI

[103] Google Scholar

[ref27] 27. CDC 2012. Fourth national report on human exposure to environmental chemicals, updated tables. Available: http://www.cdc.gov/exposurereport/pdf/FourthReport_UpdatedTables _Feb2015.pdf. Accessed 2015 Feb 1.

[ref28] 28. Parlett LE, Calafat AM, Swan SH. Women's exposure to phthalates in relation to use of personal care products. J Expo Sci Environ Epidemiol. 2013; 23:197–206. pmid:23168567
View Article
PubMed/NCBI
Google Scholar

[106] View Article

[107] PubMed/NCBI

[108] Google Scholar

[ref29] 29. Philippat C, Bennett D, Calafat AM, Picciotto IH. Exposure to select phthalates and phenols through use of personal care products among Californian adults and their children. Environ Res. 2015; 140: 369–76. pmid:25929801
View Article
PubMed/NCBI
Google Scholar

[110] View Article

[111] PubMed/NCBI

[112] Google Scholar

[ref30] 30. Calafat AM, Wong LY, Silva MJ, Samandar E, Preau JL Jr, Jia LT, et al. Selecting adequate exposure biomarkers of diisononyl and diisodecyl phthalates: data from the 2005–2006 National Health and Nutrition Examination Survey. Environ Health Perspect. 2011; 119: 50–5. pmid:20870567
View Article
PubMed/NCBI
Google Scholar

[114] View Article

[115] PubMed/NCBI

[116] Google Scholar

[ref31] 31. Schütze A, Kolossa-Gehring M, Apel P, Brüning T, Koch HM. Entering markets and bodies: increasing levels of the novel plasticizer Hexamoll DINCH in 24 h urine samples from the German Environmental Specimen Bank. Int J Hyg Environ Health. 2014; 217: 421–6. pmid:24029725
View Article
PubMed/NCBI
Google Scholar

[118] View Article

[119] PubMed/NCBI

[120] Google Scholar

[ref32] 32. Chen CY, Chou YY, Lin SJ, Lee CC. Developing an intervention strategy to reduce phthalate exposure in Taiwanese girls. Sci Total Environ. 2015; 517: 125–131. pmid:25725197
View Article
PubMed/NCBI
Google Scholar

[122] View Article

[123] PubMed/NCBI

[124] Google Scholar

[ref33] 33. Swan SH. Environmental phthalate exposure in relation to reproductive outcomes and other health endpoints in humans. Environ Res. 2008; 108: 177–84. pmid:18949837
View Article
PubMed/NCBI
Google Scholar

[126] View Article

[127] PubMed/NCBI

[128] Google Scholar

[ref34] 34. Chen ML, Chen JS, Tang CL, Mao IF. The internal exposure of Taiwanese to phthalate—an evidence of intensive use of plastic materials. Environ Int. 2008; 34:79–85. pmid:17765308
View Article
PubMed/NCBI
Google Scholar

[130] View Article

[131] PubMed/NCBI

[132] Google Scholar

[ref35] 35. Huang PC, Liou SH, Sun CW, Pan WH, Wang CJ, Wang SL. Human Biomonitoring for Phthalates Exposure from Nutrition and Health Survey in Taiwan (NAHSIT). International Society of Exposure Science conference, proceeding, Seattle, WA, USA; 2012.

[ref36] 36. Bao J, Zeng XW, Qin XD, Lee YL, Chen X, Jin YH, et al. Phthalate Metabolites in Urine Samples from School Children in Taipei, Taiwan. Arch Environ Contam Toxicol. 2015 Mar 8.
View Article
Google Scholar

[135] View Article

[136] Google Scholar

[ref37] 37. Lin LC, Wang SL, Chang YC, Huang PC, Cheng JT, Su PH, et al. Associations between maternal phthalate exposure and cord sex hormones in human infants. Chemosphere. 2011; 83: 1192–9. pmid:21272909
View Article
PubMed/NCBI
Google Scholar

[138] View Article

[139] PubMed/NCBI

[140] Google Scholar

[ref38] 38. Sathyanarayana S, Barrett E, Butts S, Wang C, Swan SH. Phthalate exposure and reproductive hormone concentrations in pregnancy. Reproduction. 2014; 147: 401–9. pmid:24196015
View Article
PubMed/NCBI
Google Scholar

[142] View Article

[143] PubMed/NCBI

[144] Google Scholar

[ref39] 39. Swan SH, Sathyanarayana S, Barrett ES, Janssen S, Liu F, Nguyen RH, et al. First trimester phthalate exposure and anogenital distance in newborns. Hum Reprod. 2015; 30: 963–72. pmid:25697839
View Article
PubMed/NCBI
Google Scholar

[146] View Article

[147] PubMed/NCBI

[148] Google Scholar

[ref40] 40. Kobrosly RW, Evans S, Miodovnik A, Barrett ES, Thurston SW, Calafat AM, et al. Prenatal phthalate exposures and neurobehavioral development scores in boys and girls at 6–10 years of age. Environ Health Perspect. 2014; 122: 521–8. pmid:24577876
View Article
PubMed/NCBI
Google Scholar

[150] View Article

[151] PubMed/NCBI

[152] Google Scholar

[ref41] 41. Toft G, Jönsson BA, Lindh CH, Jensen TK, Hjollund NH, Vested A, et al. Association between pregnancy loss and urinary phthalate levels around the time of conception. Environ Health Perspect. 2012; 120: 458–63. pmid:22113848
View Article
PubMed/NCBI
Google Scholar

[154] View Article

[155] PubMed/NCBI

[156] Google Scholar

[ref42] 42. Reddy BS, Rozati R, Reddy BV, Raman NV. Association of phthalate esters with endometriosis in Indian women. BJOG. 2006; 113: 515–20. pmid:16637895
View Article
PubMed/NCBI
Google Scholar

[158] View Article

[159] PubMed/NCBI

[160] Google Scholar

[ref43] 43. Becker K, Göen T, Seiwert M, Conrad A, Pick-Fuss H, Müller J, et al. GerES IV: phthalate metabolites and bisphenol A in urine of German children. Int J Hyg Environ Health. 2009; 212: 685–92. pmid:19729343
View Article
PubMed/NCBI
Google Scholar

[162] View Article

[163] PubMed/NCBI

[164] Google Scholar

[ref44] 44. Koch HM, Wittassek M, Brüning T, Angerer J, Heudorf U. Exposure to phthalates in 5–6 years old primary school starters in Germany—a human biomonitoring study and a cumulative risk assessment. Int J Hyg Environ Health. 2011; 214: 188–95. pmid:21371937
View Article
PubMed/NCBI
Google Scholar

[166] View Article

[167] PubMed/NCBI

[168] Google Scholar

[ref45] 45. Téllez-Rojo MM, Cantoral A, Cantonwine DE, Schnaas L, Peterson K, Hu H, et al. Prenatal urinary phthalate metabolites levels and neurodevelopment in children at two and three years of age. Sci Total Environ. 2013; 461–462: 386–90. pmid:23747553
View Article
PubMed/NCBI
Google Scholar

[170] View Article

[171] PubMed/NCBI

[172] Google Scholar

[ref46] 46. Schulz C, Wilhelm M, Heudorf U, Kolossa-Gehring M, Human Biomonitoring Commission of the German Federal Environment Agency. Update of the reference and HBM values derived by the German Human Biomonitoring Commission. Int J Hyg Environ Health. 2011; 215: 26–35.
View Article
Google Scholar

[174] View Article

[175] Google Scholar

Figures

Abstract

Introduction

Method

Results

Conclusion

Introduction

Materials and Methods

Ethics statement

Subject recruitment and data collection

Phthalate metabolite analysis

Statistical Analysis

Results

Characteristics of Subjects

Levels of eleven phthalate metabolites

Comparison of phthalate exposure among different countries

Discussion

Supporting Information

S1 Table. Main phthalate products and urinary metabolites investigated in this study.

S2 Table. Detectable rate and distribution of creatinine-adjusted levels (μg/g creatinine, or ng/ml) of phthalate metabolites a in a sample of the general Taiwanese population (N = 387) by age groups.

S3 Table. Distribution of creatinine-adjusted levels (μg/g creatinine or ng/ml) in phthalate metabolites a from a sample of the general Taiwanese population by different regions (N = 387).

S4 Table. Number a of individuals who use phthalate-containing food-related plastic products, cosmetic and personal care products, medicine and pesticides.

S5 Table. Differences in subject creatinine levels (mg/dl) by age and gender (N = 387) in our study.

S6 Table. Pearson correlation coefficients among 11 urinary phthalate metabolites (creatinine-adjusted) in Taiwanese minors (n = 97, upper right) and Taiwanese adults (n = 290, age≧18 years old, lower left), and adjusted/unadjusted creatinine levels (diagonal) for all subjects.

Acknowledgments

Author Contributions

References

S2 Table. Detectable rate and distribution of creatinine-adjusted levels (μg/g creatinine, or ng/ml) of phthalate metabolites ^a in a sample of the general Taiwanese population (N = 387) by age groups.

S3 Table. Distribution of creatinine-adjusted levels (μg/g creatinine or ng/ml) in phthalate metabolites ^a from a sample of the general Taiwanese population by different regions (N = 387).

S4 Table. Number ^a of individuals who use phthalate-containing food-related plastic products, cosmetic and personal care products, medicine and pesticides.