Table 3.

Differentiation between main VOCs emitted from biosolid samples; mean values (n = 3) ± SD; different letters in the same line indicate significant differences among volatiles in each biosolid samples (Tukey’s HSD test. P < 0.05)

Chemical compound	Chromatographic peak area/mean ± SD (× 10− 3)
	PSa	WASa	DGSa	DWSa
Alcohols
1-Decanol	20.5 ± 4.1	18.5 ± 3.8	35.4 ± 2.3	34.5 ± 1.6
2-Methyl-3-heptanol	12.8 ± 2.6a,c	46.1 ± 4.8a,d,e	11.5 ± 1.5d,f	74.5 ± 3.5c,e,f
Ethanol	47.4 ± 2.7a	851.1 ± 23.2a	11.0 ± 1.0a	231.8 ± 2.7a
1-Propanol	601.7 ± 1.8a	720.4 ± 0.8a	93.9 ± 5.6a	191.9 ± 3.4a
3-Ethyl-3-pentanol	14.2 ± 1.2	17.1 ± 2.0	16.3 ± 1.1	15.9 ± 0.8
Ketones
2-Propanone	46.7 ± 2.3c	47.7 ± 3.3e	47.2 ± 1.2f	177.1 ± 6.0c,e,f
Acetophenone	263.1 ± 15.1b,c	278.9 ± 6.3d,e	64.9 ± 2.6b,d,f	19.8 ± 1.6c,e,f
2-Hexanone	787.3 ± 5.2a	830.9 ± 3.0a	55.3 ± 2.5a	86.8 ± 1.4a
2-Heptanone	20.5 ± 1.0b	12.6 ± 2.1d	72.3 ± 4.7b.d.f	22.4 ± 2.7f
2-Octanone	47.1 ± 1.7a	26.8 ± 2.2a	44.4 ± 2.3	30.6 ± 0.9
Aromatic compounds
Benzene	884.6 ± 10.5a,b	930.7 ± 6.9a,d,e	906.0 ± 1.3b,d	890.9 ± 6.8e
1.3.5-Trimethylbenzene	21.3 ± 2.3c	6.9 ± 0.5e	14.7 ± 2.0f	89.8 ± 1.8c,e,f
o-Xylene	69.1 ± 0.8b,c	68.1 ± 1.0d,e	152.5 ± 6.0b,d,f	190.5 ± 8.4c,e,f
p-Xylene	51.2 ± 4.2b	45.8 ± 2.9d	172.8 ± 4.4b,d,f	37.0 ± 3.0f
Toluene	85.0 ± 1.4b,c	66.2 ± 2.5d,e	199.4 ± 2.6b,d,f	750.9 ± 1.8c,e,f
Sulfur compounds
Ethanethiol	963.6 ± 7.0a	53.6 ± 0.2a	653.1 ± 5.5a	545.8 ± 1.3a
Dimethyl sulfide	43.9 ± 2.2a	14.9 ± 1.7a	222.9 ± 3.9a	650.8 ± 2.1a
Dimethyl disulfide	99.4 ± 3.9a	23.6 ± 2.1a	893.4 ± 5.5a	248.0 ± 0.4a
Diethyl disulfide	13.0 ± 1.2b,c	7.5 ± 0.9d,e	768.6 ± 1.8b,d,f	985.5 ± 4.7c,e,f
Methanethiol	2888.8 ± 4.8a	90.7 ± 1.2a	110.9 ± 1.9a	771.4 ± 1.8a

^aDifferences between PS and WAS

^bDifferences between PS and DGS

^cDifferences between PS and DWS

^dDifferences between WAS and DGS

^eDifferences between WAS and DWS

^fDifferences between DGS and DWS