| Haematoxylin, [benzyl-14C]- | MC 2532 |
| HDP-CDV, sodium salt, [cytosine-2-14C]- (Hexadecyloxypropyl cidofovir, sodium salt, [cytosine-2-14C]-) | MC 2285 |
| Heptane, [1,2-3H]- | MT 1581 |
| Hexadecane, [1-14C]- Discontinued | MC 1463 |
| Hexadecane, [1,2-3H]- Discontinued | MT 1624 |
| Hexadecane, [1,2-3H]- (for use as a liquid scintillation standard) Discontinued | MT 1624S |
| 1,16-Hexadecanedioate, [3H]- | MT 2097 |
| 1-Hexadecanol, [1-14C]- | MC 1364 |
| 1-Hexadecanol, [1-3H]- | MT 1567 |
| Hexadecynoic acid, [1-14C]- | MC 1433 |
| Hexaflumuron, [dichlorophenyl-14C(U)]- | MC 2415 |
| Hexahydroxycolupulone, [3H]- | MT 1666 |
| 1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-γ-2-benzopyran, [3-14C]- (HHCB, [3-14C]-) | MC 2301 |
| Hexamethyldisiloxane, [methyl-14C]- | MC 2678 |
| Hexamethyldisiloxane, [13C6]- | MG 155 |
| 1,1,2,3,3,8-Hexamethyl-1,2,3,5,7,8-hexahydro-6-oxa-cyclopenta[b]Naphthalene, [3H]- | MT 1746 |
| Hexamidine, [11,16-14C]- | MC 2137 |
| Hexanoic acid, [1-14C]- | MC 2478 |
| Hexanoic acid, sodium salt, [1-14C]- | MC 2555 |
| Hexyl salicylate, [7-14C]- | MC 2645 |
| HHCB, [3H]- | MT 1746 |
| Hinokitiol, [3H]- | MT 2112 |
| Hippuric acid, [glycyl-1-14C]- | MC 2227 |
| D-Histidine, [2,5-3H]- | MT 957 |
| L-Histidine, [14C(U)]- | MC 2427 |
| L-Histidine, [ring-2,5-3H]- | MT 905 |
| Homosalate, [phenol-3H]- | MT 2115 |
| Homovanillic acid, [2-3H]- Discontinued | MT 1643 |
| HPMPA | M 722 |
| HPMPA, [adenine-8-14C]- | MC 2273 |
| HPMPA, [adenine-2,8-3H]- | MT 722 |
| (R)-HPMPC | M 1942 |
| HPMPC | M 833 |
| HPMPC, [2-14C]- | MC 446 |
| HPMPC, [5-3H]- | MT 833 |
| Hyaluronic acid, [3H]- | MT 2019 |
| 4-Hydrazinobenzoic acid, [ring-14C]- | MC 2194 |
| Hydroquinone, [ring-14C(U)]- | MC 1101 |
| 2'-Hydroxyacetophenone, [ring-14C(U)]- | MC 2143 |
| 6-Hydroxyaminopurine, [8-14C]- | MC 2162 |
| gamma-Hydroxybutyric acid, [2,3-3H]- Discontinued | MT 844 |
| 9-Hydroxycamptothecin, [12-3H(N)]- | MT 1524 |
| 1-Hydroxychlorpropham | M 1931 |
| 4'-Hydroxychlorpropham | M 1932 |
| 4'-Hydroxychlorpropham-O-sulfonic acid | M 1933 |
| 4'-Hydroxychlorpropham-O-sulphonic acid, [ring-14C(U)]- | MC 2445 |
| Hydroxyethylpiperidine, [carboxyl-14C]- | MC 2488 |
| 2-Hydroxyflutamide, [3H]- | MT 1521 |
| N-1-(4-Hydroxy-5-hydroxymethyl-bicyclo[3.1.0]hex-2-yl) thymine, [methyl-3H(N)]- | MT 1749 |
| 7-Hydroxymethotrexate | |
| 2-Hydroxy-4-methoxybenzophenone, [benzene-14C(U)]- | MC 2541 |
| 4-Hydroxy-3-methoxyphenylacetic acid, [2-3H]- Discontinued | MT 1643 |
| 5-Hydroxymethylcytosine, [1-13C, 1,3-15N2]- | MG 147 |
| 5-Hydroxymethyl-2'-deoxyuridine, [3H]- | MT 1781 |
| DL-2-Hydroxy-4-(methylthio)butyric acid, [carbonyl-14C]- | MC 2642 |
| 4-Hydroxy-2(E)-nonen-1-al, [2,3-3H]- Discontinued | MT 1704 |
| 2-Hydroxyoleic acid, [9,10-3H]- | MT 1881 |
| 1-[((S)-2-Hydroxy-2-oxo-1,2,4-dioxaphosphorinan-5-yl)methyl], [3H]- (cHPMPC) | MT 1713 |
| 9-(3-Hydroxy-2-phosphonyl-methoxypropyl)-adenine | M 722 |
| 9-(3-Hydroxy-2-phosphonyl-methoxypropyl)-adenine, [adenine-8-14C]- (HPMPA, [adenine-8-14C]-) | MC 2273 |
| 9-(3-Hydroxy-2-phosphonyl-methoxypropyl)-adenine, [adenine-2,8-3H]- | MT 722 |
| (S)-1-[3-Hydroxy-2-(phosphonyl-methoxy)propyl]-cytosine | M 833 |
| (S)-1-[3-Hydroxy-2-(phosphonyl-methoxy)propyl]-cytosine, [cytosine-1,3-15N2, 2,4,5-13C3]- | MG 145 |
| (S)-1-[3-Hydroxy-2-(phosphonyl-methoxy)propyl]-cytosine, [cytosine-2-14C]- | MC 446 |
| (S)-1-[3-Hydroxy-2-(phosphonyl-methoxy)propyl]-cytosine, [5-3H]- | MT 833 |
| 3-Hydroxypicolinic acid, [carboxy-14C]- | MC 2153 |
| 4-Hydroxypyrazolo[3,4-d]-pyrimidine-4-one, [3H]- | MT 653 |
| 6-Hydroxypyridine-3-carboxylic acid, [13C(U)]- | MG 162 |
| 4-Hydroxyquinoline, [benzene ring-14C]- | MC 2071 |
| 8-Hydroxyquinoline, [phenyl ring-14C(U)]- | MC 2729 |
| 25-Hydroxyvitamin D3, [3H]- | MT 2175 |
| Hypoxanthine, [14C(U)]- | MC 167 |
| Hypoxanthine, [8-14C]- | MC 147 |
| Hypoxanthine, [2,8-3H]- | MT 700 |
| Hypoxanthine, [8-3H]- | MT 1732 |