## 1 Introduction  
The quality of trace analysis in food and environmental samples mainly depends on the selected sample treatment [1]. There is an increasing demand for strategies minimizing the analyte-matrix interferences, especially in case of volatile compounds occurring at low concentrations in complex matrices. These conditions require the reduction of final volumes of analytes to furnish higher concentrations of analytes at low quantification limits [2]. Moreover, there is a demand for environmentally sustainable procedures that apply reduced volumes of organic solvents [2]. Another aspect of analytical method development is automation [3]. There are numerous advantages of automation, e.g., lower time consumption, increase of simplicity, lower probability of sample contamination and higher repeatability. These are just a few reasons for the widespread application of solid phase microextration (SPME) techniques [3].  
SPME is a relatively recent and easy to automate technique for the extraction of analytes from gaseous, liquid, and solid matrices. The simple, rapid and solvent-free technique was introduced in the early 1990s by [PERSON] and coworkers [4; 5; 6]. The SPME process is composed of two basic steps: (i) partitioning of analytes between the extraction phase and the sample matrix and (ii) desorption of concentrated extracts into an analytical instrument [7]. Due to the combination of sampling, extraction, pre-concentration and sample introduction into an analytical instrument in one single step, SPME has gained popularity in many fields of application in recent years, especially in routine laboratories and industrial applications [8; 9; 10]. Areas of application have been steadily growing, including food packaging and environmental uses.  
Automatised fiber injection systems hyphenated with gas chromatographic (GC) and gas chromatography-mass spectrometry (GC-MS) separation modules are the most popular instruments combined with SPME in use [11]. These instrumental assemblies have been successfully applied to a wide variety of compounds, especially for the extraction of volatile and semivolatile organic compounds from complex sample matrices [12]. Due to the inaccessibility of weakly volatile or thermally labile compounds to GC or GC-MS, SPME was also developed for direct coupling to high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS) [12].  
A number of reviews on SPME have already been published, dealing with food analysis [12; 13; 14; 15], environmental analysis [16; 17; 18; 19; 20; 21], calibration methods [22], SPME coatings [11; 23; 24; 25; 26], drug analysis [12; 27], the analysis of specific compounds [28; 29] and specific SPME techniques [30]. In addition, general overviews of SPME techniques and contemporary developments are provided by others [2; 6; 17; 31].  
This review provides a comprehensive overview on latest trends of SPME method development including new techniques and new devices, as well as essential parameters in SPME processes. The latest development of fiber coating development and the application of nanotechnology in SPMEtechnology are also covered extensively by the present review. Moreover, this review reports for the first time simultaneously on two important life sciences SPME application areas--food and environmental applications published over the last decade (2005-2015).