Dibutyl Phthalate Contributes to the Thyroid Receptor Antagonistic Activity in Drinking Water Processes

State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871 Beijing 100085, China.
Environmental Science & Technology (Impact Factor: 5.33). 09/2010; 44(17):6863-8. DOI: 10.1021/es101254c
Source: PubMed


It has long been recognized that thyroid hormone (TH) is essential for normal brain development in both humans and animals, and there is growing evidence that environmental chemicals can disrupt the thyroid system. In the present work, we used a two-hybrid yeast assay to screen for agonistic or antagonistic thyroid receptor (TR) mediated effects in drinking waters. We found no TR agonistic, but TR antagonistic activities in all samples from the drinking water processes. The TR antagonistic activities in organic extracts of water samples were then calibrated regarding to a known TR-inhibitor, NH3, and were expressed as the NH3 equivalents (TEQbio). The observed TEQbio in waters ranged from 180.8+/-24.8 to 280.2+/-48.2 microg/L NH3. To identify the specific compounds responsible for TR disrupting activities, the concentrations of potentially thyroid-disrupting chemicals including organochlorine pesticides (OCPs), phenols, and phthalates in organic extracts were quantitatively determined and their toxic equivalents with respect to NH3 (TEQcal) were estimated from their concentration-dependent relationships, respectively, using the same set of bioassays. Based on the TEQ approach, it was revealed that dibutyl phthalate (DBP) accounted for 53.7+/-8.2% to 105.5+/-16.7% of TEQbio. There was no effective removal of these potential thyroid disrupting substances throughout drinking water treatment processes.

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Available from: Zijian Wang, May 16, 2014
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    • "Furthermore, the half-life (t 1/2 ) of OH-initiated transformation was also calculated within 273e313 K temperature range. Fig. S6 shows that at a specified [ OH] range, the t 1/2 of four phthalates decreases as the temperature increases, based on [ OH] from 10 À14 e10 À18 M in natural waters (Wu and Linden, 2010). For example, at the highest [ OH] "
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    ABSTRACT: Transformation products (TPs) of emerging organic contaminates (EOCs) in water are still rarely considered in environmental risk assessment, although some have been found to be concern. OH is believed as an important reactive species both in indirect phototransformation and advanced oxidation technology. Thus, eco-toxicity and human estrogenic exposure risks of four phthalates and TPs during the OH-initiated photochemical process were investigated using computational approach. Four phthalates can be degraded through OH-addition and H-transfer pathways. The OH-addition TPs were predominant for dimethyl phthalates, while H-transfer TPs were predominant for other three phthalates. Compared with phthalates, OH-addition TPs (o-OH-phthalates) were one level more toxic to aquatic organisms, and m-OH-phthalates exhibit higher estrogenic activity. Although H-transfer TPs were less harmful than OH-addition TPs, some of them still have aquatic toxicity and estrogenic activity. Therefore, more attentions should be paid to photochemical TPs and original EOCs, particularly those exhibiting high estrogenic activity to humans. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Environmental Pollution 08/2015; 206:510-517. DOI:10.1016/j.envpol.2015.08.006 · 4.14 Impact Factor
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    • "For reducing the risk of phthalates contamination in drinking water, some countries and organizations have regulated the guideline values of phthalates in drinking water (in China, 8, 3, and 300 μg/L for DEHP, DBP, and DEP, respectively (NSC 2006); in WHO, 8 μg/L for DEHP (WHO 2011); in the USA, the maximum contaminant level (MCL) value (6 μg/L) for DEHP (US EPA 2006); in Japan, 100, 200, and 500 μg/L for DEHP, DBP, and BBP, respectively (Wakayama 2004)). In eastern and northern China, phthalates have been detected in 13 drinking water samples and 10 drinking water samples, respectively, ranging from no detection to 28.9 μg/L (Hu et al. 2013; Li et al. 2010a, b; Shi et al. 2012). No potential health risks to humans were identified by determining the androgen and thyroid receptor agonistic and antagonistic potencies based on reporter gene assay in eastern China (Hu et al. 2013; Shi et al. 2012). "
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    Environmental Science and Pollution Research 03/2015; 22(14). DOI:10.1007/s11356-015-4253-9 · 2.83 Impact Factor
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    • "Thyroid hormone disrupting effects have been detected in environmental samples including sediment extracts, indoor dust, industrial effluents and even water sources [7], [8]. Normal treatment processes in sewage treatment plants, including filtration, coagulation, aerobic biodegradation and ozonation are not considered to be effective for removal of endocrine disrupting chemicals [7]. "
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    PLoS ONE 10/2013; 8(10):e73883. DOI:10.1371/journal.pone.0073883 · 3.23 Impact Factor
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