scholarly journals The role of endocrine disrupters in water recycling: risk or mania?

2004 ◽  
Vol 50 (2) ◽  
pp. 215-220 ◽  
Author(s):  
L.D. Nghiem ◽  
J. McCutcheon ◽  
A.I. Schäfer ◽  
M. Elimelech

The widespread occurrence of endocrine disrupting chemicals (EDCs), such as steroid hormones, in secondary wastewater effluents has become a major concern in the water recycling practice. This paper investigates the risk of steroid hormone breakthrough during nanofiltration membrane filtration in water recycling applications. The results indicate a dynamic equilibrium between adsorption and desorption of steroid hormone with regard to the membrane. This equilibrium can be pH dependent and there is a possibility for release of steroid hormones at high pH during membrane cleaning procedures or erratic pH variations. Increase in water recovery can severely increase the hormone breakthrough concentration. The results also indicate a possibility of accumulation of steroid hormones in the NF membrane, followed by subsequent release.

2003 ◽  
Vol 3 (3) ◽  
pp. 155-160 ◽  
Author(s):  
L.D. Nghiem ◽  
A.I. Schäfer ◽  
T.D. Waite

Recent detections of endocrine-disrupting chemicals (EDCs) in effluent are of great concern to sections of the community associated with the issue of water recycling. In vitro and in vivo studies by many researchers have confirmed the impacts of EDCs on trout at the common concentration encountered in sewage effluent. Amongst many types of EDCs the impacts of steroid estrogens such as estrone, estradiol (natural hormones) and ethinylestradiol (a synthetic hormone) are prominent as they have far higher endocrine-disrupting potency than other synthetic EDCs. Given the continuous developments in membrane technology, tertiary treatment using membrane processes has been identified as a promising technology to provide a safeguard to water recycling practice and to protect the environment. This paper investigates retention and adsorptive behavior of the natural hormones estrone and estradiol by two commercial low-pressure nanofiltration membranes TFC-SR2 and TFC-S, using dead end stirred cell systems. The removal phenomena of estradiol are similar to that of estrone. pH has been found to significantly influence the adsorption of estrone and estradiol by the membranes, presumably due to hydrogen bonding. This adsorption is critical in the risk of possible release of such hormones to the product waters. Total adsorbed amounts were calculated for standard membrane elements and are indeed important.


2005 ◽  
Vol 51 (6-7) ◽  
pp. 181-192 ◽  
Author(s):  
Z. Lewandowski ◽  
H. Beyenal

The goal of this presentation is to identify biofouling mechanisms that cause undesirable effects to the membrane separation processes of flux decline and pressure drop. The underlying assumption of this presentation is that biofouling is unavoidable and that the operator cannot eliminate it entirely. This premise justifies research efforts toward understanding the mechanisms by which biofouling affects the membrane processes, rather than expecting that technology can entirely eliminate membrane biofouling in the near future. An improved understanding of biofouling mechanisms may lead to better membrane design, better membrane modules, and better membrane cleaning procedures.


2000 ◽  
Vol 14 (3) ◽  
pp. 421-428 ◽  
Author(s):  
Hisashi Masuyama ◽  
Yuji Hiramatsu ◽  
Mamoru Kunitomi ◽  
Takafumi Kudo ◽  
Paul N. MacDonald

Abstract Recently, Pregnane X receptor (PXR), a new member of the nuclear receptor superfamily, was shown to mediate the effects of several steroid hormones, such as progesterone, glucocorticoid, pregnenolone, and xenobiotics on cytochrome P450 3A genes (CYP3A) through the specific DNA sequence for CYP3A, suggesting that PXR may play a role in steroid hormone metabolism. In this paper, we demonstrated that phthalic acid and nonylphenol, endocrine-disrupting chemicals (EDCs), stimulated PXR-mediated transcription at concentrations comparable to those at which they activate estrogen receptor-mediated transcription using a transient reporter gene expression assay in COS-7 cells. However, bisphenol A, another EDC, had no effect on PXR-mediated transcription, although this chemical significantly enhanced ER-mediated transcription. In the yeast two-hybrid protein interaction assay, PXR interacted with two nuclear receptor coactivator proteins, steroid hormone receptor coactivator-1 and receptor interacting protein 140, in the presence of phthalic acid or nonylphenol. Thus, EDC-occupied PXR may regulate its specific gene expression through the receptor-coactivator interaction. In contrast, these EDCs had no effect on the interaction between PXR and suppressor for gal 1, a component of proteasome. Finally, the expression of CYP3A1 mRNA in the liver of rats exposed to phthalic acid or nonylphenol markedly increased compared with that in rats treated with estradiol, bisphenol A, or ethanol as assessed by competitive RT-PCR. These data suggest that EDCs may affect endocrine functions by altering steroid hormone metabolism through PXR.


2016 ◽  
Vol 28 (2) ◽  
pp. 205
Author(s):  
J.-H. Lee ◽  
M. H. Lee ◽  
M. J. Lee ◽  
E.-B. Jeung

Calcium, copper, iron, oxygen, and carbon dioxide are essential factors in fetal growth. These molecules are transferred by specific receptors located on the cell membrane or cytoplasm in placenta. Calcium, copper, and iron transfer genes are regulated by oestrogen, placental lactogen, and vitamin D. During pregnancy, expression of these receptors is controlled by the nutritional status of the maternal and fetal environment. Some synthetic plastics contain endocrine-disrupting chemicals (EDC), which have similar structures to steroid hormones or endogenous hormones related to reproduction. These substances disturb action of hormones (e.g. increasing oestrogen or progesterone) by interacting with their receptors or affecting the expression of transporting genes for cations. We used a BeWo cell line (human trophoblast cell line) to test the effect of EDC during pregnancy. The cells were cultured in phenol red-free DMEM supplemented with 5% charcoal dextran-stripped fetal bovine serum for 48 h to ensure the depletion of steroid hormones in the cells. Ethinyl oestradiol (EE), which activates oestrogen receptors, was used as a positive control. Then, EE (10–9, 10–8, and 10–7 M), octylpehnol (OP; 10–7, 10–6, and 10–5 M), nonylphenol (NP; 10–8, 10–7, and 10–6 M), and bisphenol A (BPA; 10–7, 10–6, and 10–5 M) were treated in BeWo cells for 48 h, and the cells were harvested. The mRNA and protein levels for calcium transporting genes (PMCA1 and TRPV6), copper transporting genes (CTR1 and ATP7A), and iron transporting genes (IREG1 and HEPH) were quantified by RT-qPCR, and Western blotting, respectively. Experiments were carried 3 times, and results were statistically analysed by GraphPad Prism6 (GraphPad Software, San Diego, CA, USA). We observed dose-dependent decreases in mRNA levels of PMCA1, TRPV6, ATP7A, and IREG1 compared with control group in OP-, NP-, or BPA-treated groups. Protein levels showed a similar pattern to mRNA levels. Based on our data, we confirmed that these EDC affect metal ion channels such as calcium, copper, and iron transporters during pregnancy.


2020 ◽  
Vol 11 ◽  
Author(s):  
Margarita Aguilera ◽  
Yolanda Gálvez-Ontiveros ◽  
Ana Rivas

Endogenous steroid hormones and Endocrine Disrupting Chemicals (EDC) interact with gut microbiota through different pathways. We suggest the use of the term “endobolome” when referring to the group of gut microbiota genes and pathways involved in the metabolism of steroid hormones and EDC. States of dysbiosis and reduced diversity of the gut microbiota may impact and modify the endobolome resulting at long-term in the development of certain pathophysiological conditions. The endobolome might play a central role in the gut microbiota as seen by the amount of potentially endobolome-mediated diseases and thereby it can be considered an useful diagnostic tool and therapeutic target for future functional research strategies that envisage the use of next generation of probiotics. In addition, we propose that EDC and other xenobiotics that alter the gut microbial composition and its metabolic capacities should be categorized into a subgroup termed “microbiota disrupting chemicals” (MDC). This will help to distinguish the role of contaminants from other microbiota natural modifiers such as those contained or released from diet, environment, physical activity and stress. These MDC might have the ability to promote specific changes in the microbiota that can ultimately result in common intestinal and chronic or long-term systemic diseases in the host. The risk of developing certain disorders associated with gut microbiota changes should be established by determining both the effects of the MDC on gut microbiota and the impact of microbiota changes on chemicals metabolism and host susceptibility. In any case, further animal controlled experiments, clinical trials and large epidemiological studies are required in order to establish the concatenated impact of the MDC-microbiota-host health axis.


2006 ◽  
Vol 20 (3) ◽  
pp. 475-482 ◽  
Author(s):  
Michelle M. Tabb ◽  
Bruce Blumberg

Abstract Endocrine-disrupting chemicals (EDC) are commonly considered to be compounds that mimic or block the transcriptional activation elicited by naturally circulating steroid hormones by binding to steroid hormone receptors. For example, the Food Quality Protection Act of 1996 defines EDC as those, that “may have an effect in humans that is similar to an effect produced by a naturally occurring estrogen, or other such endocrine effect as the Administrator may designate.” The definition of EDC was later expanded to include those that act on the estrogen, androgen, and thyroid hormone receptors. In this minireview, we discuss new avenues through which xenobiotic chemicals influence these and other hormone-dependent signaling pathways. EDC can increase or block the metabolism of naturally occurring steroid hormones and other xenobiotic chemicals by activating or antagonizing nuclear hormone receptors. EDC affect the transcriptional activity of nuclear receptors by modulating proteasome-mediated degradation of nuclear receptors and their coregulators. Xenobiotics and environmental contaminants can act as hormone sensitizers by inhibiting histone deacetylase activity and stimulating mitogen-activated protein kinase activity. Some endocrine disrupters can have genome-wide effects on DNA methylation status. Others can modulate lipid metabolism and adipogenesis, perhaps contributing to the current epidemic of obesity. Additional elucidation of these new modes of endocrine disruption will be key in understanding the nature of xenobiotic effects on the endocrine system.


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