The　reactions　of　glutathione　(GSH)　with　polybrominated　diphenyl　ethers　(PBDEs)　quinones　with　different　degrees　of　bromination　on　the　PBDEs　ring　were　studied.　Liquid　chromatography　coupled　with　mass　spectrometric　(LC-MS)　analysis　showed　that　four　types　of　adducts　were　formed　from　the　reaction　of　each　PBDEs　quinone　(PBDE-Q)　with　GSH.　The　proposed　reaction　pathway　was　confirmed　using　ion　trap-MS/MS　technique.　Our　results　demonstrate　that　adduct-1　was　formed　following　the　Michael　Addition,　a　reaction　of　the　sulfhydryl　group　from　GSH　with　electron　deficient　carbon　from　PBDEs-Q　ring.　Compared　with　other　carbons　on　the　quinone　ring,　carbon　in　position　6　has　a　smaller　steric　hindrance,　thus　the　addition　reaction　is　likely　to　occur　in　that　position.　Hydrated　quinone-GSH　adduct-1　is　easily　oxidized　to　generate　an　adduct-2　in　an　aqueous　solution.　Substitution　reaction　from　bromine　atom　on　adduct-2　quinone　ring　with　sulfhydryl　group　from　GSH　further　generates　adduct-3　that　is　unstable　and　can　be　readily　hydrolyzed　to　adduct-4　in　aqueous　solution.　Both　adduct-1　and　adduct-4　were　unstable　as　well,　immediately　oxidized　to　adduct-2　and　adduct-3　in　the　air,　respectively.　The　results　reveal　that　brominated　quinones　undergo　a　rapid　non-enzymatic　debromination　upon　reaction　with　GSH,　and　open　a　new　view　for　our　understanding　on　mechanism　of　metabolism　and　the　toxicity　of　this　class　of　compounds.　(C)　2014　Elsevier　Ltd.　All　rights　reserved.