Graduation date: 2007
While fluorochemicals have been detected all over the world and in wastewater
treatment plants, the effect of wastewater effluent on the receiving waters has not been
evaluated. In the first study, the mass flow of fluorochemicals emanating from
wastewater treatment plants along the Glatt River in Switzerland was evaluated. The
fluorochemical concentrations in daily composite samples of river water and
wastewater were measured using LC/MS/MS. On average, the seven wastewater
treatment plants proved ineffective in completely removing fluorochemicals from the
influent and in some individual cases, the effluent concentrations of fluorochemicals
were elevated when compared to the influent. Fluorochemical concentrations in
wastewater were dominated by PFOS followed by PFHxS and PFOA; PFOS was
detected in 100% of the samples. In the Glatt River, PFOS, PFOA and PFHxS were
detected in all samples. Mass flows were determined and showed that the mass
loading from the treatment plants is additive and that the mass flow along the river is
conserved. Per capita discharges for the plants along the Glatt River were calculated
and found to account for the upstream concentrations of fluorochemicals at the
headwaters of the Glatt River.
In the second study, a method for the quantitative analysis of fluorochemicals
in landfill leachates was developed to assess the amount of fluorochemicals emanating
from landfills. The method employed solid phase extraction with EnviCarb cleanup
prior to analysis by large volume injection LC/MS/MS. Perfluorocarboxylates (C4-
C10) were the dominant species observed in landfill leachates. PFBA concentrations
ranged from 63 – 1800 ng/L and PFOA concentrations ranged from 130 – 1100 ng/L.
The most abundant perfluorosulfonate measured in leachate was perfluorobutane
sulfonate (110 -2300 ng/L), which was measured in all samples. PFOS was also
detected in all samples at concentrations from 38 – 160 ng/L, including in leachates
obtained from sites which received waste only after the 2002 phase out of PFOS.
Fluoroalkyl sulfonamides, which was are precursors to PFOS and PFBS were also
detected in leachate, often in concentrations exceeding that of their degradation
product. Concentrations of MeFOSAA, which is indicative of the chemicals used in
textile and carpet treatments, ranged from ND – 290 ng/L, while concentrations of
EtFOSAA, which is associated with polymeric paper coating applications, ranged
from 7 to 480 ng/L. The analogous C4 sulfonamide, MeFBSAA, was observed at
concentrations ranging from 11 – 540 ng/L including at sites that have been closed
since before the phase out of PFOS and subsequent introduction of PFBS as a
substitute. The distribution of fluorochemicals in landfills that operated under
leachate recirculation conditions were not different from landfills that did not circulate
leachate.