**3. Results**

#### **3.1. Comparison of PAH analysis methods for gasification residues (1st experiment)**

Table 1 summarizes the Σ EPA16 PAH content in the three gasification residue samples in mg/ kg dry mass (DM) as determined by the two different analytical methods. On average, the analysis according to DIN 13877:B resulted in PAH contents more than 4 times higher compared to the analysis according to DIN 13877:A. The standard errors of the mean (SEM) are indicated after the average values. The difference between the sample means (n=3) of the two analysis methods is significant (p < 0.01) according to the applied permutation version of ANOVA.

Figure 2 depicts the results from Table 1 in two box-and-whisker plots.
