The behavior of organophosphates and ethers during riverbank filtration and
groundwater flow was assessed to determine their suitability as organic
tracers. Four sampling campaigns were conducted at the Oderbruch polder,
Germany to establish the presence of chlorinated flame retardants (TCEP, TCPP,
TDCP), non-chlorinated plasticizers (TBEP, TiBP, TnBP), and hydrophilic ethers
(1,4-dioxane, monoglyme, diglyme, triglyme, tetraglyme) in the Oder River,
main drainage ditch, and anoxic aquifer. Selected parameters were measured in
order to determine the hydro-chemical composition of both, river water and
groundwater. The results of the study confirm that organophosphates (OPs) are
more readily attenuated during bank filtration compared to ethers. Both in the
river and the groundwater, TCPP was the most abundant OP with concentrations
in the main drainage ditch ranging between 105 and 958 ng L−1. 1,4-dioxane,
triglyme, and tetraglyme demonstrated persistent behavior during bank
filtration and in the anoxic groundwater. In the drainage ditch concentrations
of 1,4-dioxane, triglyme, and tetraglyme ranged between 1090 and 1467 ng L− 1,
37 and 149 ng L− 1, and 496 and 1403 ng L− 1, respectively. A positive
correlation was found for the inorganic tracer chloride with 1,4-dioxane and
tetraglyme. These results confirm the possible application of these ethers as
environmental organic tracers. Both inorganic and organic compounds showed
temporal variability in the surface- and groundwater. Discharge of the river
water, concentrations of analytes at the time of infiltration and attenuation
were identified as factors influencing the variable amounts of the analytes in
the surface and groundwater. These findings are also of great importance for
the production of drinking water via bank filtration and natural and
artificial groundwater recharge as the physicochemical properties of ethers
create challenges in their removal
