The levels of perfluroalkyl substances (PFASs), polybrominated diphenyl ethers (PBDEs) and hexabro-mocyclododecane (HBCDDs) were studied in Australian landfill leachate and biosolids. Leachate wascollected from 13 landfill sites and biosolids were collected from 16 wastewater treatment plants(WWTPs), across Australia. Perfluorohexanoate (PFHxA) (12–5700 ng/L) was the most abundant inves-tigated persistent, bioaccumulative and toxic (PBT) chemical in leachate. With one exception, meanconcentrations of PFASs were higher in leachate of operating landfills compared to closed land-fills. Polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane isomers (HBCDDs) weredetected typically at operating landfills in comparatively lower concentrations than the PFASs. Decabro-modiphenyl ether (BDE-209) (