A survey of the digested sludge from 14 U.K. wastewatertreatment plants was carried out to obtain contemporaryU.K. data on the concentrations of certain classes of persistentorganic compounds for which data are scarce and toassess whether U.K. sludge was likely to comply with thesludge limits for PCBs and PAHs proposed by the EuropeanUnion. Total PAH (24 compounds) concentrations rangedfrom 67 to 370 mg/kg dw, in line with data from other countries;all the samples would exceed the proposed EU limit.Total PCB concentrations were 110-440
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g/kg dw, wellbelow the proposed EU limit. Total PCN concentrations rangedfrom 50 to 190
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g/kg. Total synthetic musk concentrationsranged from 2.1 to 86 mg/kg dw; there were a few veryhigh concentrations of HHCB and AHTN in the samples. Totalconcentrations of the short- and medium-chainedpolychlorinated alkanes ranged between 7 and 200 mg/kgand between 30 and 9700 mg/kg, respectively. Thesevery high concentrations are indicative of chemicals withnumerous and ongoing diffuse sources.