Time-integrated monitoring of polycyclic aromatic hydrocarbons (PAHs) in groundwater using the Ceramic Dosimeter passive sampling device

Natural attenuation research at the contaminated megasite Zeitz

“…Conceptual and site-specific modelling of reactive transport using both a deterministic and a stochastic approach (e.g., Gödeke et al, 2004), allowing to quantify 'Natural Attenuation' by accounting also for the inherent uncertainty of field data; the simulations will determine whether the contaminant plume is at steady state or not and will evaluate the concentrations and mass fluxes to be expected at different distances downstream from the contamination source Geophysical investigation and monitoring including electrical methods and aquifer mapping using tomography (Hoffmann and Dietrich, 2004) Direct, integral measurement of the contaminant mass fluxes at predefined control planes downstream from the contamination source (multiple well pumping tests, mathematical inversion of the time-concentration curves measured during pumping) (Bayer-Raich et al, 2004) Evaluation of the natural capacity of the aquifer material to immobilise hydrophobic compounds, using the lithocomponentapproach Reactive-multi-tracer tests for the quantification of the specific interactions between contaminants and aquifer matrix (effective redox capacity) Stable isotope measurements for the integral evaluation of in situ biodegradation of organic contaminants in the aquifer (see for a review Meckenstock et al, 2004) Long-term, time-integrated (passive) chemical and toxicological monitoring of the contaminant plume using dosimeters and toximeters; quantification of the toxicological potential in the aquifer and its variation in time and space (Bopp et al, 2005;Bopp, 2004;Schirmer et al, 2004a,b) 1974, dimethyl formamid replaced phenol as the solvent for the benzene refinery. Reorganisation after the re-unification of Germany in 1990 caused the shutdown of the plant because lignite-based benzene production was no longer economically feasible.…”

“…That the toxicological analysis performed at the megasite in Zeitz helped identify this previously neglected phenomenon comprises a further proof of the integral function and value of toxicity assessment at large contaminated sites. Currently under development is a long-term monitoring plan based on both conventional snapshot groundwater sampling and application of time-integrating passive samplers for chemical and toxicological analysis to minimise the potential long-term risk for down-gradient receptors, especially the water resources beyond the contaminant plume (Martin et al, 2003;Bopp et al, 2003Bopp et al, , 2004Bopp et al, , 2005.…”

Time-integrated monitoring of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in urban and industrial wastewaters using a ceramic toximeter and the CALUX bioassay

“…A value of 2.0 was previously determined and used in field applications with ceramic-based passive samplers (Bopp et al, 2005; Martin et al, 2003). Since there are no direct measurements for aqueous diffusivity of PCDD/Fs, we have used an empirical formula Eq.…”

“…It must act as a perfect sink, which means that it must not release the trapped molecules even if the concentration of the analytes around the sampler decreased to zero (Weiß et al, 2007). The scientific validity and cost effectiveness of using this technique for volatile organic compounds (VOCs) in water had been previously documented (Bopp et al, 2005; Verreydt et al, 2010). In a recent laboratory study, we validated the use of this sampler for dioxin-contaminated water (Addeck et al, 2012).…”

Combined chemical and toxicological long-term monitoring for AhR agonists with SPMD-based virtual organisms in drinking water Danjiangkou Reservoir, China

“…The samplers imitate the exposition of animals in water which leads to them being also referred to as virtual organism (VO). The passive sampling of surface water contaminants has many advantages over conventional and active sampling approaches which can be time-integrating and long-term sampling without a need for pumps or bailers (Bopp et al 2005). This is particularly useful for monitoring low concentration contaminants in remote area where power is difficult available.…”