Table 1 VOMs identified in urine samples from LC and CTRL groups by NTME/GC–MS methodology and respective possible origin (End - VOM endogenously produced, Ex – VOM resulting from exogenous sources, as diet (F), microbial (M), drug metabolism (D), environmental contamination (E), according to the data available in the human metabolome database17, Unkn – VOM whose origin is currently unknown).
VOMs | RT (min) | KI Exp | KI Lit | LC | CTRL | Possible Orign | |||
|---|---|---|---|---|---|---|---|---|---|
FO | Total Area | FO | Total Area | ||||||
1 | Pentane | 4.38 | 660 | 650 | 82 | 9.3E + 04 | 100 | 6.3E + 04 | End/Ex |
2 | Methyl chloride | 4.49 | 671 | — | 71 | 7.6E + 05 | 100 | 1.5E + 05 | End/Ex |
3 | Hexane | 4.54 | 676 | 600 | 100 | 7.5E + 04 | 97 | 4.9E + 04 | End/Ex |
4 | Ethyl ether | 4.60 | 682 | 640 | 94 | 1.7E + 04 | 87 | 1.3E + 04 | Unkn |
5 | Isoprene | 4.67 | 689 | 633 | 100 | 9.4E + 05 | 100 | 8.0E + 05 | End |
6 | Methanethiol | 4.82 | 703 | 702 | 100 | 1.6E + 06 | 100 | 1.3E + 06 | End |
7 | Acetaldehyde | 4.85 | 706 | 703 | 88 | 3.1E + 06 | 97 | 4.9E + 05 | End/Ex(DM) |
8 | Carbon disulfide | 5.08 | 726 | 723 | 100 | 1.1E + 06 | 100 | 2.0E + 05 | Ex |
9 | Dimethyl sulfide | 5.21 | 737 | 737 | 94 | 6.3E + 04 | 100 | 8.2E + 04 | End/Ex(DM) |
10 | trans-2-Methyl-1,3-pentadiene | 5.45 | 757 | 760 | 100 | 9.4E + 04 | 83 | 1.4E + 04 | Unkn |
11 | Furan | 5.59 | 768 | 760 | 100 | 1.9E + 07 | 100 | 2.0E + 07 | End |
12 | Acetone | 5.84 | 788 | 785 | 100 | 2.6E + 07 | 100 | 3.7E + 07 | End(M) |
13 | Tetrahydro-2,2,5,5-tetramethylfuran | 6.42 | 830 | — | 100 | 5.2E + 05 | 93 | 4.6E + 06 | Unkn |
14 | 2-Methylfuran | 6.59 | 842 | 843 | 100 | 3.2E + 06 | 100 | 3.0E + 06 | End |
15 | 3-Methylfuran | 7.12 | 876 | 877 | 82 | 5.3E + 05 | 97 | 2.0E + 06 | Ex(F) |
16 | 2-Butanone | 7.20 | 881 | 881 | 94 | 3.8E + 06 | 100 | 5.1E + 06 | End |
17 | 3-Methyl-2-butanone | 7.90 | 915 | 918 | 100 | 8.5E + 05 | 90 | 1.4E + 06 | End |
18 | Benzene | 8.22 | 927 | 924 | 100 | 6.3E + 04 | 80 | 2.8E + 05 | Ex(E) |
19 | 2,5-Dimethylfuran | 8.59 | 940 | 943 | 100 | 5.5E + 05 | 80 | 6.7E + 05 | Ex(F) |
20 | 2-Ethylfuran | 8.62 | 941 | 941 | 100 | 7.0E + 05 | 70 | 3.8E + 05 | Ex(F) |
21 | 1,6-Dimethylhepta-1,3,5-triene | 8.71 | 944 | — | 100 | 4.1E + 05 | 93 | 2.3E + 05 | Unkn |
22 | 1,2,5,5-Tetramethyl-1,3-cyclopentadiene | 8.99 | 953 | — | 100 | 2.0E + 05 | 100 | 1.5E + 05 | Unkn |
23 | 5-tert-Butyl-1,3-cyclopentadiene | 8.93 | 951 | — | 94 | 4.0E + 05 | 63 | 3.1E + 05 | End/Ex(F) |
24 | 2-Pentanone | 9.37 | 966 | 969 | 100 | 1.4E + 07 | 100 | 1.7E + 07 | Ex(F) |
25 | 2,4-Dimethyl-3-pentanone | 10.15 | 989 | 995 | 100 | 4.7E + 06 | 100 | 1.3E + 06 | End/Ex(F) |
26 | 2-Hexanone | 11.10 | 1001 | 1082 | 100 | 9.0E + 05 | 100 | 4.9E + 05 | End |
27 | 3,3-Dimethyl-6-methylenecyclohexene | 10.78 | 1006 | — | 100 | 1.6E + 05 | 93 | 9.7E + 04 | Unkn |
28 | 3-Methyl-2-pentanone | 10.91 | 1008 | 1005 | 100 | 1.2E + 06 | 100 | 1.1E + 06 | End/Ex(F) |
29 | Thiophene | 11.25 | 1016 | 1017 | 100 | 1.9E + 05 | 100 | 2.4E + 05 | End/Ex (F) |
30 | 1,3-Dimethyl-1-cyclohexene | 11.66 | 1024 | — | 100 | 9.5E + 05 | 100 | 8.8E + 05 | Unkn |
31 | Toluene | 12.06 | 1032 | 1033 | 100 | 8.7E + 05 | 100 | 2.1E + 06 | Ex(PF) |
32 | 3-Hexanone | 12.71 | 1044 | 1047 | 100 | 7.1E + 05 | 100 | 1.7E + 06 | End |
33 | 2-Methyl-3-hexanone | 12.93 | 1044 | — | 94 | 5.6E + 05 | 60 | 5.9E + 05 | Unkn |
34 | 2-Ethyl-4-methylimidazole | 12.97 | 1049 | — | 100 | 1.5E + 05 | 100 | 2.4E + 05 | Unkn |
35 | Dimethyl disulfide | 13.90 | 1065 | 1065 | 100 | 9.8E + 07 | 100 | 1.0E + 08 | End |
36 | Hexanal | 14.52 | 1075 | 1075 | 100 | 9.3E + 05 | 93 | 3.4E + 05 | End |
37 | 2-Methylthiophene | 14.99 | 1083 | 1085 | 100 | 1.7E + 05 | 97 | 1.9E + 05 | Ex(F) |
38 | 2-Methyl-(E)-2-butenal | 15.41 | 1089 | 1088 | 100 | 1.4E + 05 | 83 | 1.0E + 05 | End/Ex(F) |
39 | 6,6-Dimethylhepta-2,4-diene | 15.53 | 1091 | — | 100 | 1.3E + 05 | 93 | 7.1E + 04 | Unkn |
40 | 2-Ethyl-5-methylfuran | 15.64 | 1092 | 1034 | 94 | 7.8E + 05 | 73 | 9.0E + 04 | End/Ex(F) |
41 | 2,2,6-Trimethyl-6-vinyltetrahydropyran | 15.83 | 1095 | 1095 | 100 | 1.4E + 05 | 100 | 2.5E + 05 | End/Ex(F) |
42 | 7,7-Dimethyl-9-oxatricyclo[6.2.2.0(1,6)]dodecan-10-one | 17.21 | 1114 | — | 94 | 1.5E + 05 | 93 | 1.2E + 05 | Unkn |
43 | 4-Heptanone | 17.42 | 1117 | 1118 | 100 | 5.0E + 07 | 100 | 3.0E + 07 | End |
44 | p-Xylene | 18.05 | 1124 | 1123 | 100 | 1.1E + 05 | 100 | 2.4E + 05 | Unkn |
45 | 1,5,5-Trimethyl-6-methylene-cyclohexene | 18.21 | 1126 | — | 100 | 1.7E + 05 | 100 | 1.6E + 05 | Unkn |
46 | Ethyl methyl disulfide | 18.51 | 1130 | 1141 | 94 | 6.5E + 04 | 97 | 5.3E + 04 | Ex(F) |
47 | α-Phellandrene | 19.21 | 1138 | 1143 | 76 | 3.0E + 04 | 90 | 9.5E + 04 | End/Ex(F) |
48 | 3-Heptanone | 19.60 | 1143 | 1148 | 100 | 6.6E + 04 | 97 | 9.3E + 04 | End/Ex(F) |
49 | α-Terpinene | 20.27 | 1150 | 1159 | 100 | 7.1E + 05 | 100 | 2.4E + 06 | End/Ex(F) |
50 | 1,4-Cineole | 20.80 | 1156 | 1164 | 100 | 4.2E + 05 | 100 | 1.2E + 06 | End/Ex(F) |
51 | 2-Heptanone | 22.37 | 1172 | 1173 | 100 | 1.0E + 06 | 100 | 4.8E + 05 | End |
52 | Eucalyptol | 23.33 | 1181 | 1183 | 82 | 2.7E + 05 | 97 | 4.7E + 05 | Ex(D) |
53 | 1-Ethyl-3-methylbenzene | 24.54 | 1192 | 1200 | 88 | 9.2E + 04 | 90 | 2.1E + 05 | Unkn |
54 | 2-Pentylfuran | 25.55 | 1201 | 1203 | 100 | 8.7E + 05 | 97 | 4.9E + 05 | End/Ex(F) |
55 | γ-Terpinene | 25.88 | 1205 | 1213 | 100 | 3.1E + 05 | 100 | 1.2E + 06 | Ex(F) |
56 | 3,4-Dimethylthiophene | 28.15 | 1226 | 1240 | 100 | 3.7E + 05 | 100 | 1.2E + 06 | Ex(F) |
57 | o-Cymene | 28.99 | 1234 | 1248 | 100 | 1.3E + 07 | 100 | 7.0E + 07 | Ex(F) |
58 | Isoterpinolene | 29.87 | 1242 | 1270 | 65 | 1.5E + 05 | 97 | 8.0E + 05 | End/Ex(F) |
59 | Methyl allyl disulfide | 31.13 | 1253 | 1253 | 100 | 4.6E + 06 | 100 | 2.8E + 06 | Ex(F) |
60 | 1,3-Dithiane | 31.64 | 1257 | 1296 | 100 | 6.5E + 05 | 100 | 8.9E + 05 | End/Ex(F) |
61 | 1,3-Dimethyl-2-ethylbenzene | 34.74 | 1281 | 1347 | 100 | 9.5E + 06 | 83 | 1.5E + 07 | Unkn |
62 | 2,2,6-Trimethylcyclohexanone | 35.21 | 1284 | 1284 | 100 | 8.9E + 04 | 93 | 8.7E + 04 | End/Ex(F) |
63 | 1,2,3-Trimethylbenzene | 36.63 | 1295 | 1295 | 100 | 3.3E + 05 | 100 | 4.4E + 05 | Unkn |
64 | 2-methoxy-5-methyl-Thiophene | 39.71 | 1321 | — | 100 | 1.4E + 05 | 93 | 7.7E + 04 | Unkn |
65 | Dimethyl trisulfide | 42.37 | 1343 | 1343 | 100 | 7.5E + 06 | 100 | 8.4E + 06 | End/Ex(M) |
66 | 2-Methyl-5-(methylthio)furan | 44.17 | 1358 | — | 100 | 1.1E + 06 | 97 | 5.9E + 05 | Ex(F) |
67 | Isophorone | 46.55 | 1376 | 1541 | 100 | 5.5E + 05 | 93 | 1.7E + 05 | End/Ex(F) |
68 | 2,3-Dihydro-1,1,5,6-tetramethyl-1H-indene | 48.96 | 1393 | — | 82 | 9.9E + 05 | 100 | 1.1E + 06 | Unkn |
69 | 1,1,6,7-Tetramethyl-Indan | 49.61 | 1398 | — | 65 | 7.1E + 05 | 93 | 1.1E + 06 | Unkn |
70 | p-Cymenene | 50.24 | 1400 | — | 100 | 4.4E + 06 | 97 | 1.8E + 07 | End/Ex(F) |
71 | Durene | 55.67 | 1449 | 1446 | 94 | 5.8E + 05 | 90 | 1.4E + 06 | Unkn |
72 | Acetic acid | 58.07 | 1468 | 1465 | 94 | 1.4E + 06 | 93 | 1.5E + 06 | End/Ex(DM) |
73 | 1,2,5,5,6,7-Hexamethylbicyclo[4.1.0]hept-2-en-4-one | 60.25 | 1484 | — | 94 | 4.5E + 05 | 100 | 9.6E + 05 | Unkn |
74 | 1-(4-Methoxyphenyl)-1,3-butanedione | 60.57 | 1487 | — | 100 | 2.7E + 05 | 100 | 5.4E + 05 | Unkn |
75 | 2-Ethyl-1-hexanol | 61.07 | 1490 | 1490 | 100 | 2.9E + 05 | 60 | 1.1E + 05 | End/Ex(F) |
76 | m-Anisalcohol | 61.85 | 1496 | — | 100 | 3.1E + 05 | 93 | 3.6E + 05 | Ex(F) |
77 | 2-Acetylfuran | 61.98 | 1497 | 1498 | 100 | 3.7E + 05 | 90 | 4.6E + 05 | Ex(F) |
78 | 5-Methylfurfural | 69.92 | 1565 | 1567 | 100 | 6.5E + 04 | 60 | 5.6E + 04 | Ex(F) |
79 | trans-(-)-5-Methyl-3-(1-methylethenyl)-cyclohexene | 69.91 | 1565 | — | 100 | 6.4E + 04 | 43 | 4.6E + 04 | Unkn |
80 | 1,1,4,5-tetramethyl-2,3-dihydro indene | 75.43 | 1613 | — | 100 | 2.1E + 05 | 60 | 1.8E + 05 | Unkn |
81 | 1,1,3-Trimethyl indane | 78.58 | 1648 | — | 100 | 1.3E + 05 | 70 | 1.7E + 05 | Unkn |
82 | Dehydro-Ar-ionene | 83.90 | 1706 | 1712 | 100 | 1.0E + 07 | 100 | 4.6E + 06 | Ex(F) |
83 | α-Curcumene | 87.38 | 1764 | 1764 | 71 | 6.5E + 04 | 100 | 3.0E + 06 | Unkn |
84 | 1-(2,6,6-Trimethyl-1,3-cyclohexadien-1-yl)-2-buten-1-one | 89.92 | 1810 | 1801 | 94 | 1.9E + 05 | 63 | 1.8E + 05 | End |
85 | 1,1,3-Trimethyl-1H-indene | 90.57 | 1829 | — | 94 | 2.5E + 05 | 77 | 7.0E + 05 | Unkn |
86 | 2,5,8-Trimethyl-1,2-dihydronaphthalene | 90.88 | 1838 | 1999 | 94 | 5.9E + 05 | 33 | 3.3E + 05 | Unkn |
87 | Guaiacol | 91.91 | 1868 | 1868 | 100 | 5.6E + 05 | 100 | 4.4E + 05 | End |
88 | α-Calacorene | 93.21 | 1909 | 1910 | 100 | 6.6E + 05 | 100 | 1.5E + 06 | End/Ex(F) |
89 | Phenol | 95.12 | 2009 | 2009 | 100 | 2.1E + 06 | 100 | 1.2E + 06 | End/Ex(E) |
90 | p-Cresol | 96.37 | 2074 | 2074 | 100 | 1.5E + 07 | 100 | 1.1E + 07 | End/Ex(M) |
91 | 1-(2,3,6-Trimethylphenyl)-3-buten-2-one | 97.02 | 2107 | 2180 | 100 | 3.5E + 05 | 80 | 2.6E + 05 | Unkn |
92 | p-Ditolylmethane | 98.25 | 2169 | — | 100 | 1.1E + 05 | 83 | 1.4E + 05 | Unkn |
93 | Carvacrol | 98.50 | 2182 | 2183 | 100 | 7.0E + 05 | 90 | 4.8E + 05 | End/Ex(F) |
94 | 4-tert-Butyl-2-Bromophenol | 98.72 | 2193 | — | 100 | 4.1E + 05 | 97 | 1.9E + 05 | End/Ex(F) |
95 | Cadalene | 98.94 | 2204 | 2203 | 100 | 2.6E + 05 | 97 | 4.7E + 05 | Unkn |
96 | 4-tert-Butylphenol | 99.83 | 2248 | — | 100 | 1.1E + 06 | 100 | 5.8E + 05 | End/Ex(F) |
97 | 3,5-Di-t-butylphenol | 100.72 | 2256 | 2310 | 71 | 6.1E + 04 | 100 | 1.4E + 05 | End |
98 | Benzoic Acid | 102.75 | 2402 | 2405 | 76 | 1.4E + 05 | 97 | 1.2E + 05 | Ex(FM) |
