1. Mother city for Romania (5)
2 That is some aluminium in disorder (8)
3. Old city under siege (5)
4. Bird in the money (7)
5. Man with tie askew in the middle (8)
6. Half-hidden toy inside (5)
7. Sailor, sailor (6)
8. Pub for a mixed-up girl (8)
9. Exam for secretarial worker (8)
10. TV programme containing rotten material? The opposite (7)
10 is indeed Humerus IMHO. "The opposite " at the end of the clue sometimes mean reverse the cryptic (which is phrased that way because it makes more "sense" ), so on this case it is HUMUS (rotten material) containing TV programme (ER).