Abstract Filings from a printed circuit board were extracted and analysed for unreacted tetrabromobisphenol A (TBBPA). About 0.7 μg free TBBPA per gram circuit board were found, corresponding to about 4 μg free TBBPA per gram of TBBPA used in the circuit board. These values are probably underestimates of the true levels due to incomplete extraction. Surficial sediments taken upstream and downstream from a plastics industry where TBBPA is used were analysed for both TBBPA and its dimethylated derivative, McTA. The TBBPA concentration was 34 ng/g dry weight upstream of the industry and 270 ng/g dry weight downstream. The corresponding concentrations of MeTA were 24 and 1500 ng/g dry weight respectively. TBBPA was also found in two sewage sludge samples analysed. One sample was collected from the sewage treatment plant that receives leach water from a landfill with wastes from the investigated plastics industry. The other sample was collected from a sewage treatment plant where no known users of TBBPA are connected. The levels of TBBPA in these samples were similar to those found in the samples upstream from the industry. During the analysis of a number of biological samples for lipophilic brominated substances, McTA has been screened, but so far no McTA has been detected.