## 1 Introduction  
More than 1000 different active pharmaceuticals ingredients (APIs) are today used in Sweden [1]. The release of APIs into the water environment has been a subject of research for more than 30 years [2], and their ubiquitous occurrence at varying concentration levels have been shown in wastewater, surface water, sediment, groundwater and drinking water [3; 4; 5; 6; 7; 8; 9]. Large research resources have been spent worldwide on investigating the occurrence of pharmaceutical residues in the water phase, a significantly smaller proportion resources of these compounds' presence in sewage sludge [10]. The production of sewage treatment plant (STP) sludge in Sweden is estimated at approximately 207,500 tons of dry matter, finalized at over 400 STPs. The sludge contains, besides carbon, about 3% phosphorus and 3.5% nitrogen. This means that around 600 tons of phosphorus and 7000 tons of nitrogen can be recycled in Sweden and returned to the soil via sludge each year [11]. Sludge spread on farmland is the largest single use category, since it is the most economical outlet for sludge and offers the opportunity to recycle plant nutrients and organic matter to soil for crop production. Agricultural use is estimated at approximately 50,000 tons, which corresponds to 25% of the total Swedish net production [12]. Sludge spreading in Sweden is regarded as an environmentally hazardous activity, but is still not subject to authorization or reporting, though authorities may impose stricter requirements in individual cases. From a European perspective the European Council Directive 86/278/EEC on the protection of soil, regulates sewage sludge use in agriculture in the EU. In several EU countries Directive 86/278/EEC is complemented by national legislation on soil protection; however, such legislation does not include regulation of pharmaceutical residues, even though there is increasing societal awareness and debate on the fate of APIs during sludge management. The fact that the chemical load in the form of pharmaceuticals and most other emerging contaminants (ECs), is unregulated both in wastewater effluents and in produced sewage sludge at the STPs, may in part be due to the fact that sludge chemically is a very complex matrix, which severely complicates the chemical analysis [13; 14]. Nevertheless, sewage sludge is a sink for many of these substances [15] and given the spreading of sludge on farmland makes it important to seek valid results on its content of APIs. Traditionally, a variety of techniques have been used for extracting organic pollutants, including APIs, from sewage sludge such as Soxhlet, ultrasound assisted extraction, microwave-assisted extraction, mechanical shaking, supercritical fluid extraction and pressurized liquid extraction [16; 17; 18; 19; 20]. Since APIs hold a variety of physicochemical properties it is difficult to find a single method capable of analysing such a large number of differing chemical substances. Furthermore, emerging in recent years, there is a growing environmental concern in chemistry reshaping this field towards \"green chemistry\" [21], which is defined as the design of chemical products and processes that reduce or eliminate the use or generation of hazardous substances [22]. One possible technique possessing properties with the potential of meeting both these criteria is pressurized hot water extraction (PHWE) [23]. From a scientific perspective, experimental work on PHWE dates back to at least 1994 when [PERSON] et al. [24], interested in finding environmentally friendly extraction methods, suggested water as a clean solvent for the extraction of non-polar analytes from environmental samples. In their pioneering work, performed on their in-house constructed equipment using stainless-steel columns, they found an increase in solubility of non-polar organics such as polyaromatic hydrocarbons (PAHs) in water with increasing temperature.