Irrigation of treated wastewater in Braunschweig, Germany: an option to remove pharmaceuticals and musk fragrances.

In this study the fate of pharmaceuticals and personal care products which are irrigated on arable land with treated municipal wastewater was investigated. In Braunschweig, Germany, wastewater has been irrigated continuously for more than 45 years. In the winter time only the effluent of the sewage treatment plant (STP) of Braunschweig is used for irrigation, while during summer digested sludge is mixed with the effluent. In the present case study six wells and four lysimeters located in one of the irrigated agricultural fields were monitored with regard to the occurrence of 52 pharmaceuticals and two personal care products (PPCPs; e.g. betablockers, antibiotics, antiphlogistics, carbamazepine, musk fragrances, iodinated contrast media (ICM) and estrogens). No differences in PPCP pollution of the groundwater were found due to irrigation of STP effluents with and without addition of digested sludge, because many polar compounds do not sorb to sludge and lipophilic compounds are not mobile in the soil-aquifer. Most of the selected PPCPs were never detected in any of the lysimeter or groundwater samples, although they were present in the treated wastewater irrigated onto the fields. In the groundwater and lysimeter samples primarily the ICM diatrizoate and iopamidol, the antiepileptic carbamazepine and the antibiotic sulfamethoxazole were detected up to several mugl(-1), while the acidic pharmaceuticals, musk fragrances, estrogens and betablockers were likely sorbed or transformed while passing the top soil layer. Potential estrogenic effects are likely to disappear after irrigation, since the most potent steroid estrogens were not measurable.

Determination of pharmaceuticals, iodinated contrast media and musk fragrances in sludge by LC/tandem MS and GC/MS.

Analytical methods have been developed that allow for the determination of antiphlogistics, lipid regulators, the antiepileptic carbamazepine, cytostatic agents, the psychiatric drug diazepam and iodinated contrast media (ICM) as well as two major polycyclic musk fragrances HHCB (galaxolide) and AHTN (tonalide) in activated and digested sludge. The procedures consist of ultrasonic solvent extraction (USE) using methanol/acetone or pressurized liquid extraction (PLE) using 100% methanol. Clean-up was performed with C18ec material and silica gel followed by LC tandem MS (electrospray or atmospheric pressure chemical ionization) detection for pharmaceuticals and iodinated contrast media as well as GC/MS in the SIM mode for musk fragrances. Absolute recoveries from spiked activated sludge in general ranged from 88+/-4 to 119+/-20% for ICM and were 78+/-15 and 87+/-10% for the AHTN and HHCB, respectively. For the pharmaceuticals, absolute recoveries in activated sludge ranged between 43 and 78%. Subsequently, compensation of losses was carried out by using surrogate standards (acidic pharmaceuticals: fenoprop, neutral pharmaceuticals: dihydro-carbamazepine, musk fragrances: AHTN-D3). With one exception the recoveries were also adequate in digested sludge ranging from 43% to 120%.

A rapid method to measure the solid-water distribution coefficient (Kd) for pharmaceuticals and musk fragrances in sewage sludge.

Pharmaceuticals and personal care products are omnipresent in wastewater world-wide. In order to predict their sorption quantities onto sludge in wastewater treatment plants (WWTPs), the solid-water distribution coefficients (Kd values) of selected pharmaceuticals (antiphlogistics, estrogens, lipid regulators, anti-epileptic and cytostatic agents) and polycyclic musk fragrances (HHCB, AHTN) were determined in primary and secondary sludges taken from a German municipal WWTP. For the Kd determination, batches of primary and secondary sludge slurries were spiked with the respective target compounds and slowly stirred under defined conditions (e.g. an argon atmosphere). Finally, the water and solid sludge phases were analysed. The Kd values of pharmaceuticals ranged from <1 to 500 L kg(-1), while those for the polycyclic musk fragrances AHTN and HHCB proved to be up to 5300 and 4900 L kg(-1), respectively. The primary and secondary sludge showed significant differences for some pharmaceuticals such as Diclofenac and Cyclophosphamide due to the different pH and composition of the two sludges. The removal rate from the water phase caused by sorption in a WWTP can be reasonably predicted on the basis of the Kd values.

Determination of estrogens in sludge and sediments by liquid extraction and GC/MS/MS.

Two methods have been developed that enable the determination of estrogens down to 2 ng/g in digested and activated sludge from domestic sewage treatment plants (STPs) and down to 0.2 ng/g in freshwater sediments. The method for sludge analysis consists of solvent extraction; a gel permeation chromatography (GPC) cleanup step, a 1 g silica gel column; and finally, detection by GC-ion trap MS/MS of the silylated estrogens with MSTFA. For sediments, the solvent extraction was successively followed by silica gel cleanup, solid phase enrichment (SPE), and a HPLC cleanup before derivatization and GC/MS/MS detection. Mean recoveries of the estrogens mainly exceeded 70% in sludge and 90% in sediments. In activated and digested sewage sludge, estrone and 17beta-estradiol were detected up to 37 ng/g and 49 ng/g, respectively, and 17alpha-ethinylestradiol up to 17 ng/g. The occurrence of estrogens in digested sludge indicates that estrogens can be persistent during sludge digestion. In river sediments, estrone and 17beta-estradiol were detected up to 2 ng/g (estrone), and the contraceptive 17alpha-ethinylestradiol was found with a maximum of 0.9 ng/g. Mestranol, a prodrug for 17alpha-ethinylestradiol, was not detected either in sludge or in sediments.