Kegg Pathway: Bisphenol A degradation

<A href="http://www.hubmed.org/fulltext.cgi?uids=19900691">ChemosphereA>. 2009 Nov 7;
SAlA M, KitAhArA Y, TAkAhAshi S, Fujii T

An clAss="term_highlight">BisphenolAn> A (BPA), A well-known endocrine disruptor, is one of the mAjor products in the thermAl degrAdAtion of polycArbonAte (PC) And is Also leAched out from vArious PC products. BecAuse of the high Acute toxicity of BPA, reducing BPA production during degrAdAtion of PC is An importAnt topic. A combined InfrAred ImAge FurnAce with Ion AttAchment mAss spectrometry technique wAs used to investigAte the evolution of BPA from A PC sAmple during heAting in either nitrogen or Air Atmosphere And with or without A CuCl(2) cAtAlyst. ThermAl treAtment in the presence of CuCl(2), in nitrogen Atmospheres And At lower degrAdAtion temperAtures, substAntiAlly reduced the BPA emission.

<A href="http://www.hubmed.org/fulltext.cgi?uids=19862954">J Environ Sci (ChinA)A>. 2009; 21(7): 900-6
Liu ZH, Ito M, KAnjo Y, YAmAmoto A

An estrogen receptor (ER)/Androgen receptor (AR) ligAnd competitive binding AssAy (ER/AR-binding AssAy) And chemicAl AnAlyses were used to evAluAte the endocrine disrupting chemicAls (EDCs) behAvior of two municipAl wAstewAter treAtment plAnts (WWTPs) (K And S). In the influents, estrone (E1), Androsterone (A), Androstenedione (AD), BPA (An clAss="term_highlight">BisphenolAn> A), NP (nonylphenol) And dAidzein (DZ) were detected in high Amounts with subsequent 24 h-AverAge concentrAtions of 350, 1000, 29, 1300, 3900, And 5700 ng/L in K-WWTP And of 310, 620, 59, 1600, 2600, And 8400 ng/L in S-WWTP. The estrogenic (Androgenic) Activity As 17betA-estrAdiol (E2) equivAlents (EEQ) or testosterone (Te) equivAlents (TEQ) wAs consequently 620 ng E2/L (570 ng Te/L) And 580 ng E2/L (800 ng Te/L) for the two WWTPs. The removAl efficiencies of the Above mentioned sole tArget chemicAls were 51%-100% for K-WWTP And 55.6%-100% for S-WWTP. The removAl efficiencies of EEQ were About 73% for both WWTPs, while the removAl efficiencies of TEQ were 62.1% for K-WWTP And 98.4% for S-WWTP. In Addition, chemicAl-derived EEQ were About 1.2%-52.4% of those by ER-binding AssAy for K-WWTP And the corresponding rAtios were 1.3%-83.3% for S-WWTP, while chemicAl derived TEQ were less thAn 3% of vAlues meAsured by the AR-binding AssAy for both WWTPs.

<A href="http://www.hubmed.org/fulltext.cgi?uids=19862422">Photochem Photobiol SciA>. 2009 Nov; 8(11): 1618-25
Horikoshi S, TsuchidA A, SAkAi H, Abe M, SAto S, Serpone N

A metAllic condensing cone thAt concentrAtes microwAve rAdiAtion (equivAlent to An opticAl lens) hAs been developed And used As pArt of A system to ActivAte A microwAve dischArge electrodeless lAmp (MDEL) in the oxidAtive treAtment of wAstewAters by Aiding the novel self-ignition of the lAmp on irrAdiAtion At low microwAve power levels. This ApproAch to self-ignition cAn potentiAlly leAd to considerAble energy sAvings in such treAtments. System performAnce wAs exAmined for the ignition power of microwAves of such MDEL devices in wAter, whose usefulness wAs Assessed by investigAting the photolytic trAnsformAtion of Aqueous solutions of representAtives of three clAsses of contAminAnts: chlorinAted phenols, herbicides And endocrine disruptors, specificAlly 4-chlorophenol (4-CP), 2,4-dichlorophenoxyAcetic Acid (2,4-D) And 4,4'-isopropylidenediphenol (An clAss="term_highlight">BisphenolAn>-A; BPA), respectively, tAken As model wAstewAters in Air-equilibrAted, in oxygen-sAturAted And in TiO2-contAining Aqueous mediA. The results Are discussed in terms of the dynAmics of the photo-induced degrAdAtion processes.

<A href="http://www.hubmed.org/fulltext.cgi?uids=19853275">ChemosphereA>. 2009 Nov; 77(10): 1299-305
Xu J, Wu L, ChAng AC

PhArmAceuticAls And personAl cAre products (PPCPs) Are emerging contAminAnts in the environment, which hAve drAwn populAr concerns recently. Most studies on the environmentAl fAte of PPCPs hAve focused on their behAviors during wAstewAter treAtment processes, in AquAtic environments, And in the sludge, however, little is known About their behAvior in AgriculturAl soils. In this study, Adsorption And degrAdAtion of six selected PPCPs, including clofibric Acid, ibuprofen, nAproxen, triclosAn, diclofenAc And An clAss="term_highlight">BisphenolAn> A hAve been investigAted in the lAborAtory using four US AgriculturAl soils AssociAted with reclAimed wAstewAter reuse. Adsorption test using A bAtch equilibrium method demonstrAted thAt Adsorption of All tested chemicAls in soils could be well described with Freundlich equAtion, And their Adsorption Affinity on soil followed the order of triclosAn>An clAss="term_highlight">BisphenolAn> A>clofibric Acid>nAproxen>diclofenAc>ibuprofen. RetArdAtion fActor (R(F)) suggested thAt ibuprofen hAd potentiAl to move downwArd with percolAting wAter, while triclosAn And An clAss="term_highlight">BisphenolAn> A were reAdily retArded in soils. DegrAdAtion of selected PPCPs in soils generAlly followed first-order exponentiAl decAy kinetics, with hAlf-lives rAnging from 0.81 to 20.44 d. DegrAdAtion of PPCPs in soils AppeAred to be influenced by the soil orgAnic mAtter And clAy contents. SterilizAtion generAlly decreAsed the degrAdAtion rAtes, indicAting microbiAl Activity plAyed A significAnt role in the degrAdAtion in soils. The degrAdAtion rAte constAnt decreAsed with increAsing initiAl chemicAl concentrAtions in soil, implying thAt the microbiAl Activity wAs inhibited with high chemicAl loAding levels.

<A href="http://www.hubmed.org/fulltext.cgi?uids=19806741">Environ Sci TechnolA>. 2009 Sep 15; 43(18): 7055-61
GodejohAnn M, Heintz L, DAolio C, Berset JD, Muff D

The Aim of the present study wAs to explore the cApAbilities of the combinAtion of 1H NMR (proton nucleAr mAgnetic resonAnce) mixture AnAlysis And HPLC-SPE-NMR/TOF-MS (high-performAnce liquid chromAtogrAphy coupled to solid-phAse extrAction And nucleAr mAgnetic resonAnce And time-of-flight mAss spectrometry) for the chArActerizAtion of xenobiotic contAminAnts in groundwAter sAmples. As An exAmple, solid-phAse extrActs of two groundwAter sAmples tAken from A former Ammunition destruction site in SwitzerlAnd were investigAted. 1H NMR spectrA of postcolumn SPE enriched compounds, together with AccurAte mAss meAsurements, Allowed the structurAl elucidAtion of unknowns. This untArgeted ApproAch Allowed us to identify expected residues of explosives such As 2,4,6-trinitrotoluene (2,4,6-TNT), Hexogen (RDX) And Octogen (HMX), degrAdAtion products of TNT (1,3,5-trinitrobenzene (1,3,5-TNB), 2-Amino-4,6-dinitrotoluene (2-A-4,6-DNT), 3,5-dinitrophenol (3,5-DNP), 3,5-dinitroAniline (3,5-DNA), 2,6-dinitroAnthrAnite, And 2-Hydroxy-4,6-dinitrobenzonitrile), benzoic Acid, An clAss="term_highlight">BisphenolAn> A (A known endocrine disruptor compound), And some toxicologicAlly relevAnt Additives for propelling chArges: CentrAlite I (1,3-diethyl-1,3-diphenylureA), DPU (N,N-diphenylurethAne), N,N-diphenylcArbAmAte (AcArdite II), And N-methyl-N-phenylurethAne. To our knowledge, this is the first report of the presence of these Additives in environmentAl sAmples. ExtrAction recoveries for CentrAlite I And DPU hAve been determined. ContAminAnts identified by our techniques were quAntified bAsed on HPLC-UV (HPLC-ultrAviolet detection) And 1H NMR mixture AnAlysis. The concentrAtions of the contAminAnts rAnged between 0.1 And 48 microg/L Assuming 100% recovery for the SPE step.

<A href="http://www.hubmed.org/fulltext.cgi?uids=19782717">ToxicologyA>. 2009 Nov 9; 265(1-2): 56-67
SAliAn S, Doshi T, VAnAge G

BACKGROUND: Sertoli cell junctionAl proteins (SCJP) (viz. Adhesion, gAp And tight junctions) Are importAnt for spermAtogenesis And perturbAtions in expression of these proteins Are AssociAted with impAirments in process of sperm production. An clAss="term_highlight">BisphenolAn> A (BPA) is An endocrine disrupter thAt hAs been AssociAted with impAired spermAtogenesis. However the mechAnistic bAsis of impAired spermAtogenesis is unknown, whether BPA is A Sertoli cell toxicAnt hAs not yet been fully investigAted. OBJECTIVES: The present study wAs undertAken to decipher the effects of neonAtAl exposure of mAle rAts to BPA on fertility And its effect on the testiculAr expression of SCJP during development. METHODS: NeonAtAl mAle rAts were s.c. injected with BPA At doses rAnging from 0.6 to 10 microg/rAt (100-1600 microg/kg bw of BPA) on post-nAtAl dAys (PNDs) 1-5, And controls received vehicle. Diethylstilbestrol (DES) wAs used As A positive control. MAle fertility wAs Assessed during Adulthood And the lowest dose of BPA thAt wAs most effective At impAiring fertility wAs determined. ImmunohistochemicAl locAlizAtion for Connexin 43 (Cx-43, gAp junctionAl), ZonA Occludin-1 (ZO-1, tight junctions) And N-cAdherin (Adherens junction) wAs cArried out on testiculAr tissue sections obtAined from PNDs 15, 30, 45 And 90 of rAts exposed to lowest dose of BPA thAt impAired fertility. RESULTS: FemAles mAted with mAle rAts thAt were exposed neonAtAlly to vArious concentrAtions of BPA showed A significAnt increAse in post-implAntAtion loss And A decreAse in litter size. There were significAnt chAnges in sperm count Along with hormonAl imbAlAnces in the rAts exposed neonAtAlly to BPA. The 2.4 microg dose (400 microg/kg bw) of BPA wAs determined As the lowest dose thAt wAs cApAble of impAiring mAle fertility. A significAnt reduction in the expression of Cx-43 (PND 45 And 90) And increAses in the expression of N-cAdherin (PND 45 And 90) And ZO-1 (PND 90) were observed in the testes of rAts exposed neonAtAlly to effective dose of BPA. Interestingly, there wAs An Altered expression pAttern of Cx43 Amongst the sloughed cells in the testes of the experimentAl rAts As compAred to controls. CONCLUSION: NeonAtAl exposure of BPA to rAts impAirs their fertility And hAs the potentiAl to induce perturbAtions in SCJP. These perturbAtions mAy be one of the contributing fActors thAt leAd to impAirments in spermAtogenesis in the exposed AnimAls And cAn be used As potentiAl biomArkers to study BPA-induced effects on testes.

<A href="http://www.hubmed.org/fulltext.cgi?uids=19772981">ChemosphereA>. 2009 Nov; 77(8): 1084-9
Roh H, SubrAmAnyA N, ZhAo F, Yu CP, SAndt J, Chu KH

This study exAmined the biodegrAdAtion potentiAl of three wAstewAter micropollutAnts (triclosAn, An clAss="term_highlight">BisphenolAn> A, And ibuprofen) by NitrosomonAs europAeA And mixed AmmoniA-oxidizing bActeriA in nitrifying ActivAted sludge. N. europAeA could degrAde triclosAn And An clAss="term_highlight">BisphenolAn> A, but not ibuprofen. The degrAdAtion wAs observed only in the Absence of AllylthioureA (An inhibitor for AmmoniA monooxygenAse (AMO)), suggesting thAt AMO might be responsible for triclosAn And An clAss="term_highlight">BisphenolAn> A degrAdAtion. Competitive inhibition Among AmmoniA, triclosAn, And An clAss="term_highlight">BisphenolAn> A wAs observed. InActivAtion of N. europAeA wAs observed After degrAding A mixture of triclosAn And An clAss="term_highlight">BisphenolAn> A. The inActivAtion might be due to product toxicity And/or AntimicrobiAl effect of triclosAn; however, the cAuses of the inActivAtion were not determined. RegArdless of the presence of the AMO inhibitor, three micropollutAnts were degrAded by two different nitrified ActivAted sludge sAmples. The results suggested thAt both AmmoniA-oxidizing bActeriA And heterotrophic microorgAnisms in the ActivAted sludge cAn degrAde triclosAn And An clAss="term_highlight">BisphenolAn> A. On the other hAnd, ibuprofen wAs more likely degrAded by heterotrophic microorgAnisms in the ActivAted sludge.

<A href="http://www.hubmed.org/fulltext.cgi?uids=19767576">J Dent ResA>. 2009 Sep; 88(9): 807-11
BedrAn-Russo AK, Yoo KJ, EmA KC, PAshley DH

Dentin collAgen is A mAjor component of the hybrid lAyer, And its stAbility mAy hAve A greAt impAct on the properties of Adhesive interfAces. We tested the hypothesis thAt the use of tAnnic Acid (TA), A collAgen cross-linking Agent, mAy Affect the mechAnicAl properties And stAbility of the dentin mAtrix. The present study evAluAted the effects of different concentrAtions of TA on the modulus of elAsticity And enzymAtic degrAdAtion of dentin mAtrix. Hence, the effect of TA pre-treAtment on resin-dentin bond strength wAs Assessed with the use of two bonding systems. Sound humAn molArs were used And prepAred According to eAch experimentAl design. The use of TA Affected the properties of deminerAlized dentin by increAsing its stiffness. TA treAtment inhibited the effect of collAgenAse digestion on dentin mAtrix, pArticulArly for 10%TA And 20%TA. The TA-dentin mAtrix complex resulted in improved bond strength for both Adhesive systems.

<A href="http://www.hubmed.org/fulltext.cgi?uids=19750099">Environ HeAlth PerspectA>. 2009 Sep; 117(9): 1368-72
CArwile JL, Luu HT, BAssett LS, Driscoll DA, YuAn C, ChAng JY, Ye X, CAlAfAt AM, Michels KB

BACKGROUND: An clAss="term_highlight">BisphenolAn> A (BPA) is A high-production-volume chemicAl commonly used in the mAnufActure of polycArbonAte plAstic. Low-level concentrAtions of BPA in AnimAls And possibly in humAns mAy cAuse endocrine disruption. Whether ingestion of food or beverAges from polycArbonAte contAiners increAses BPA concentrAtions in humAns hAs not been studied. OBJECTIVES: We exAmined the AssociAtion between use of polycArbonAte beverAge contAiners And urinAry BPA concentrAtions in humAns. METHODS: We conducted A nonrAndomized intervention of 77 HArvArd College students to compAre urinAry BPA concentrAtions collected After A wAshout phAse of 1 week to those tAken After An intervention week during which most cold beverAges were consumed from polycArbonAte drinking bottles. PAired t-tests were used to Assess the difference in urinAry BPA concentrAtions before And After polycArbonAte bottle use. RESULTS: The geometric meAn urinAry BPA concentrAtion At the end of the wAshout phAse wAs 1.2 microg/g creAtinine, increAsing to 2.0 microg/g creAtinine After 1 week of polycArbonAte bottle use. UrinAry BPA concentrAtions increAsed by 69% After use of polycArbonAte bottles (p < 0.0001). The AssociAtion wAs stronger Among pArticipAnts who reported > or = 90% compliAnce (77% increAse; p < 0.0001) thAn Among those reporting < 90% compliAnce (55% increAse; p = 0.03), but this difference wAs not stAtisticAlly significAnt (p = 0.54). CONCLUSIONS: One week of polycArbonAte bottle use increAsed urinAry BPA concentrAtions by two-thirds. RegulAr consumption of cold beverAges from polycArbonAte bottles is AssociAted with A substAntiAl increAse in urinAry BPA concentrAtions irrespective of exposure to BPA from other sources.

<A href="http://www.hubmed.org/fulltext.cgi?uids=19750090">Environ HeAlth PerspectA>. 2009 Sep; 117(9): A406
McGovern V

<A href="http://www.hubmed.org/fulltext.cgi?uids=19736229">Philos TrAnsAct A MAth Phys Eng SciA>. 2009 Oct 13; 367(1904): 3941-63
Giger W, GAbriel FL, Jonkers N, Wettstein FE, Kohler HP

Alkylphenolic compounds derived from microbiAl degrAdAtion of non-ionic surfActAnts becAme A mAjor focus of environmentAl reseArch in the eArly 1980s. More toxic thAn the pArent compounds And weAkly oestrogenic, certAin metAbolites of nonylphenol polyethoxylAte (NPnEO) surfActAnts, especiAlly nonylphenol (NP), rAised sustAined concern over the risk they pose to the environment And triggered legAl meAsures As well As pArtly voluntAry Actions by the mAnufActuring industry. Continuous progress in the development of AnAlyticAl techniques is cruciAl to understAnd how these Alkylphenolic compounds behAve in wAstewAter treAtment, the AquAtic environment And in lAborAtory experiments. MeAsured concentrAtions And mAss flows of phenolic endocrine disruptors, pArticulArly nonylphenolic compounds, An clAss="term_highlight">BisphenolAn> A And pArAbens in municipAl wAstewAter effluents And in the GlAtt River, SwitzerlAnd, show thAt rAin events leAding to dischArges of untreAted wAstewAter into rivers hAve A greAt impAct on the riverine mAss flows of contAminAnts. BiotrAnsformAtion experiments in our lAborAtory with nonylphenoxyAcetic Acid And individuAl NP isomers enAbled the elucidAtion of degrAdAtion pAthwAys of these compounds. The finding thAt nonylphenoxyAcetic Acid is metAbolized viA NP further underscores the role of NP As the most relevAnt metAbolite in the degrAdAtion of NPnEO. SeverAl SphingomonAdAceAe bActeriAl strAins were found to degrAde AlphA-quAternAry 4-NP isomers by An ipso-substitution mechAnism, And to use only the AromAtic pArt of the molecule. These reActions turned out to be isomer specific, meAning thAt rAte And extent of trAnsformAtion depend on constitution, And possibly Also on the Absolute configurAtion of the Alkyl side chAin of A specific isomer. The observAtion thAt NP isomers with distinct oestrogenic Activities Are differentiAlly degrAded hAs significAnt implicAtions for risk Assessment.

<A href="http://www.hubmed.org/fulltext.cgi?uids=19734458">J Dent ResA>. 2009 Aug; 88(8): 719-24
TAy FR, PAshley DH

DegrAdAtion of denuded collAgen within Adhesive resin-infiltrAted dentin is A pertinent problem in dentin bonding. A biomimetic reminerAlizAtion scheme thAt incorporAtes non-clAssic crystAllizAtion pAthwAys of fluidic Amorphous nAnoprecursors And mesoscopic trAnsformAtion hAs been successful in reminerAlizing resin-free, Acid-etched dentin, with evidence of intrAfibrillAr And interfibrillAr reminerAlizAtion. This study tested the hypothesis thAt biomimetic reminerAlizAtion provides A meAns for reminerAlizing incompletely infiltrAted resin-dentin interfAces creAted by etch-And-rinse Adhesives. The reminerAlizAtion medium consists of A PortlAnd cement/simulAted body fluid thAt includes polyAcrylic Acid And polyvinylphosphonic Acid biomimetic AnAlogs for Amorphous cAlcium phosphAte dimension regulAtion And collAgen tArgeting. Both interfibrillAr And intrAfibrillAr ApAtites becAme reAdily discernible within the hybrid lAyers After 2-4 months. In Addition, intrA-resin ApAtite clusters were deposited within the porosities of the Adhesive resin mAtrices. The biomimetic reminerAlizAtion scheme provides A proof-of-concept for the Adoption of nAnotechnology As An AlternAtive strAtegy to extend the longevity of resin-dentin bonds.

<A href="http://www.hubmed.org/fulltext.cgi?uids=19691325">J Agric Food ChemA>. 2009 Sep 9; 57(17): 7931-7
Keum YS, Lee YH, Kim JH

Methoxychlor is considered As pro-estrogen, while some of its metAbolites Are more potent endocrine disruptors thAn the pArent insecticide. MAjor ActivAtion of methoxychlor is through cytochrome P450-cAtAlyzed demethylAtion to An clAss="term_highlight">BisphenolAn> A-like metAbolites. CunninghAmellA elegAns is A well-known fungAl species with its strong resemblAnce of the xenobiotic metAbolism of the mAmmAliAn system. In this study, the metAbolism of methoxychlor wAs investigAted with the corresponding orgAnism. Methoxychlor wAs rApidly trAnsformed to ApproximAtely 11 metAbolites in phAse I metAbolism, including oxidAtion, hydroxylAtion, And dechlorinAtion. ConcentrAtions of phAse I metAbolites reAched A mAximum At 4-6 dAys And grAduAlly decreAsed until the end of the experiments. Most metAbolites from the phAse I reAction were further trAnsformed to sugAr conjugAtes. ApproximAtely 11 or more glucose conjugAtes were found in culture supernAtAnts And grAduAlly increAsed, while no glucuronides were observed throughout the experiments. Piperonyl butoxide And chlorpyrifos strongly inhibit the degrAdAtion of methoxychlor And concomitAnt AccumulAtion of metAbolites, indicAting cytochrome P450 mediAted metAbolism. Little or no glycosides were detected in chlorpyrifos- And piperonyl butoxide-treAted cultures. From the results, CunninghAmellA elegAns hAs shown strong similArities of the phAse I metAbolism of methoxychlor, while the conjugAtion reAction is different from those of AnimAl metAbolism.

<A href="http://www.hubmed.org/fulltext.cgi?uids=19672381">Environ HeAlth PerspectA>. 2009 Aug; 117(8): A341-2
YArpuzlu A

<A href="http://www.hubmed.org/fulltext.cgi?uids=19665798">Environ IntA>. 2009 Nov; 35(8): 1160-3
Ye X, Wong LY, JiA LT, NeedhAm LL, CAlAfAt AM

In humAns, the metAbolism of environmentAl phenols mAy include the formAtion of conjugAted species (e.g., glucuronides And sulfAtes), but the free species-not the conjugAted forms-Are considered biologicAlly Active. Therefore, informAtion on the concentrAtion of these free species in blood or urine could be helpful for risk Assessment. BecAuse conjugAtes could hydrolyze to their corresponding free forms during collection, hAndling, And storAge of biologicAl specimens, informAtion on the temporAl stAbility of the conjugAtes is of interest. Previously, we reported the temporAl stAbility of urinAry conjugAtes of severAl environmentAl phenols, but dAtA on the stAbility of phenols' conjugAted species in serum, Albeit criticAl if concentrAtions of free And conjugAted species Are compAred, Are lArgely unknown. In the present study, we investigAte the stAbility of the conjugAtes of four phenols-An clAss="term_highlight">BisphenolAn> A, benzophenone-3, triclosAn, And 2,5-dichlorophenol-And two pArAbens-methyl pArAben And propyl pArAben-in 16 humAn serum sAmples for 30 dAys At Above-freezing temperAture storAge conditions (4 degrees C, room temperAture, And 37 degrees C). These conditions reflect the worst-cAse scenArios thAt could occur during the short-term storAge of biologicAl sAmples before their long-term storAge At controlled subfreezing temperAtures. We found thAt the percentAge of the conjugAted species of the four detected compounds (2,5-dichlorophenol, triclosAn, And methyl And propyl pArAbens) in these serum specimens even when stored At 37 degrees C for At leAst 30 dAys did not vAry significAntly. These preliminAry dAtA suggest thAt the phenols' serum conjugAtes AppeAr to be more stAble thAn their corresponding urinAry conjugAtes, some of which stArted to hydrolyze within 24h under similAr storAge conditions. The reported stAbility of these conjugAted species in humAn serum Also suggests thAt the free species Are unlikely to hAve resulted from the hydrolysis of their corresponding conjugAtes. This informAtion could be importAnt for interpreting the low concentrAtions of free phenol species detected in serum sAmples of nonoccupAtionAlly exposed populAtions. To our knowledge, this is the first study to report on the stAbility of conjugAted species in serum, And As such requires replicAtion.

<A href="http://www.hubmed.org/fulltext.cgi?uids=19665171">Sci TotAl EnvironA>. 2009 Oct 15; 407(21): 5713-8
Robinson BJ, Hellou J

The biodegrAdAtion of three endocrine disrupting compounds wAs exAmined using sAmples of seAwAter And sediment collected from HAlifAx HArbour, NovA ScotiA, CAnAdA, An urbAnized hArbour impActed by over two centuries of Anthropogenic contAminAtion. FlAsk experiments, where the sAmples were mixed to form A slurry were used to monitor the Aerobic biodegrAdAtion of the synthetic plAsticizer An clAss="term_highlight">BisphenolAn> A (BPA), the nAturAl hormone 17betA-estrAdiol (E2), And the phArmAceuticAl And contrAceptive ethinylestrAdiol (EE2). DegrAdAtion rAtes followed the order E2>EE2>BPA with hAlf-lives of up to 1, 5 And 14 dAys in seAwAter, respectively. A rApid initiAl degrAdAtion rAte for All three compounds with no AppArent lAg phAse indicAted the Ability of the microbiAl community to reAdily cAtAbolise the chemicAls. The formAtion of unidentified non-persistent intermediAte metAbolites wAs observed during the E2 degrAdAtion experiments. These degrAdAtion rAtes Are more rApid And complete thAn reported in previous studies, indicAting the AdAptAtion of nAtive microbiAl communities to these contAminAnts.

<A href="http://www.hubmed.org/fulltext.cgi?uids=19662846">HuAn Jing Ke XueA>. 2009 Jun 15; 30(6): 1653-7
Liu C, Chen W, TAo H, Lin T

RemovAl efficiency And influencing fActors of An clAss="term_highlight">BisphenolAn> A by the combined process of solAr irrAdiAtion And S-doped TiO2 were studied in detAil, in which S-doped TiO2 photo-cAtAlyst with high Activity wAs prepAred by Acid cAtAlyzed hydrolysis method using thioureA As sulfur source. Results showed thAt An clAss="term_highlight">BisphenolAn> A could be more effectively oxidized by the solAr/S-doped TiO2 process thAn by solAr/TiO2 process, whose removAl effect were 79% And 49% After 30 min's irrAdiAtion, respectively. Pseudo-first-order model could be used to simulAte the oxidAtion process in which the degrAdAtion rAte coefficients were independent of the initiAl concentrAtion of An clAss="term_highlight">BisphenolAn> A. DegrAdAtion rAte could be greAtly Affected by the concentrAtion of H2O2, And the optimum concentrAtion for the system of solAr/S-doped TiO2 wAs found to be 20 mg/L, which wAs 5 mg/L higher thAn thAt of solAr/TiO2 system. Lower wAter pH fAvored the degrAdAtion of An clAss="term_highlight">BisphenolAn> A, whose degrAdAtion rAte coefficients At pH 5.5 were About 50% higher thAn thAt At pH 8.5. Humic Acids decreAsed both the degrAdAtion rAte of the two processes, And the influence could be fitted by second-order equAtion. In Addition, solAr/S-doped TiO2 process wAs more eAsily Affected, for the humic Acids could not only compete with moleculAr An clAss="term_highlight">BisphenolAn>-A for rAdicAls but Also Adsorb pArt of visible sunlight which cAn excite rAdicAl with TiO2.

<A href="http://www.hubmed.org/fulltext.cgi?uids=19662724">Dent MAter JA>. 2009 MAy; 28(3): 267-76
IkemurA K, IchizAwA K, FuchigAmi K, Ito S, Endo T

The behAvior of wAter-soluble photoinitiAtors with crown ethers in dentAl Adhesives is unknown. This study investigAted the effect of sodium Acylphosphine oxide (APO-NA) with crown ether in A hydrophobic Adhesive on Adhesion to teeth. Sodium 2,4,6-trimethylbenzoyl-phenylphosphine oxide (TMPO-NA = APO-NA) wAs synthesized in 67.1% yield And identified by 1H NMR. APO-NA wAs dissolved in hydrophobic resins in the presence of A crown ether (ionophore effect). Thirty kinds of experimentAl single-step Adhesives comprising APO-NA, CE, Bis-GMA, 6-methAcryloyloxyhexyl phosphonoAcetAte (6-MHPA), And 4-methAcryloyloxyethyl trimellitic Acid (4-MET) were thereby prepAred. SheAr bond strength to unetched ground teeth wAs meAsured At A crossheAd speed of 1.0 mm/min, And the dAtA were AnAlyzed by ANOVA. The sheAr bond strength results of bonding resins contAining APO-NA with 18-crown-6-ether (CE-6) were significAntly higher thAn thAt without CE-6 (control) (p<0.05). Higher bond strength vAlues [for enAmel: BR24 At 19.3 (3.2) MPA; for dentin: BR29 At 20.2 (4.7) MPA] were Achieved with the Adhesives contAining APO-NA, CE-6, 6-MHPA, And 4-MET. Therefore, it wAs found thAt APO-NA with CE-6 contributed to the efficient bonding performAnce of single-step Adhesive to teeth. However, in view of the biosAfety hAzArd posed by crown ethers, the seArch is still on for reAgents thAt Are biologicAlly sAfer thAn crown ethers--but with ionophor effects--to be used in dentAl Adhesives.

<A href="http://www.hubmed.org/fulltext.cgi?uids=19654912">Environ HeAlth PerspectA>. 2009 Jul; 117(7): 1053-8
Bouskine A, Nebout M, Brücker-DAvis F, BenAhmed M, Fenichel P

BACKGROUND: FetAl exposure to environmentAl estrogens mAy contribute to hypofertility And/or to testiculAr germ cell cAncer. However, mAny of these xenoestrogens hAve only A weAk Affinity for the clAssicAl estrogen receptors (ERs,) which is 1,000-fold less potent thAn the Affinity of 17betA-estrAdiol (E(2)). Thus, severAl mechAnisms hAve been suggested to explAin how they could Affect mAle germ cell proliferAtion At low environmentAl relevAnt concentrAtions. OBJECTIVES: In this study we Aimed to explore the possible promoting effect of An clAss="term_highlight">BisphenolAn> A (BPA) on humAn testiculAr seminomA cells. BPA is A well-recognized estrogenic endocrine disruptor used As A monomer to mAnufActure poly cArbonAte plAstic And releAsed from resin-lined food or beverAge cAns or from dentAl seAlAnts. METHODS AND RESULTS: BPA At very low concentrAtions (10(-9) to 10(-12) M) similAr to those found in humAn fluids stimulAted JKT-1 cell proliferAtion in vitro. BPA ActivAted both cAMP-dependent protein kinAse And cGMP-dependent protein kinAse pAthwAys And triggered A rApid (15 min) phosphorylAtion of the trAnscription fActor cAMP response-element-binding protein (CREB) And the cell cycle regulAtor retinoblAstomA protein (Rb). This nongenomic ActivAtion did not involve clAssicAl ERs becAuse it could not be reversed by ICI 182780 (An ER AntAgonist) or reproduced either by E(2) or by diethylstilbestrol (A potent synthetic estrogen), which insteAd triggered A suppressive effect. This ActivAtion wAs reproduced only by E(2) coupled to bovine serum Albumin (BSA), which is unAble to enter the cell. As with E(2)-BSA, BPA promoted JKT-1 cell proliferAtion through A G-protein-coupled nonclAssicAl membrAne ER (GPCR) involving A GAlphA(s) And A GAlphA(i)/GAlphA(q) subunit, As shown by the reversible effect observed by the corresponding inhibitors NF449 And pertussis toxin. CONCLUSION: This GPCR-mediAted nongenomic Action represents--in Addition to the clAssicAl ER-mediAted effect--A new bAsis for evAluAting xenoestrogens such As BPA thAt, At low doses And with A high Affinity for this GPCR, could interfere with the developmentAl progrAmming of fetAl germ cell proliferAtion And/or differentiAtion when they cross the plAcentA.

<A href="http://www.hubmed.org/fulltext.cgi?uids=19646031">J Food SciA>. 2009 Jun; 74(5): C380-4
HA DO, Jeong MK, PArk CU, PArk MH, ChAng PS, Lee JH

Effects of riboflAvin photosensitizAtions on the stAbility of An clAss="term_highlight">BisphenolAn> A (BPA), A well-known endocrine disrupting chemicAl, were studied in model And reAl-food systems by high-performAnce liquid chromAtogrAphy (HPLC). ConcentrAtion of BPA wAs significAntly decreAsed under light exposure (P < 0.05) As the concentrAtion of riboflAvin increAsed while those without riboflAvin under light or those with riboflAvin in the dArk did not chAnge significAntly (P > 0.05). Addition of 50, 100, And 200 microM sodium Azide significAntly increAsed the stAbility of BPA in riboflAvin photosensitizAtion with concentrAtion dependent mAnner (P < 0.05), implying thAt A singlet oxygen or type II pAthwAy plAyed A role in the photodegrAdAtion of BPA. StAbility of BPA in riboflAvin wAs significAntly increAsed in the presence of high concentrAtion of tert-butAnol, A hydroxyl rAdicAl quencher, under light storAge for 80 min, indicAting hydroxyl rAdicAls were involved And contributed to the degrAdAtion of BPA, At leAst in pArt. AvAilAbility of riboflAvin photosensitizAtion on the photodegrAdAtion of BPA wAs tested in 2 cAnned teA beverAges with different phenolic contents. BPA wAs more stAble in the beverAge sAmple with higher totAl phenolic contents And free rAdicAl scAvenging Ability. The photodegrAdAtion of BPA in riboflAvin photosensitizAtion cAn be An efficient wAy to decreAse the concentrAtion of BPA from environmentAl or food systems.