His labours lead to a load of rubbish (7)
I believe the answer is:
dustman
'his labours lead' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'a load of rubbish' is the wordplay.
I cannot quite see how this works, but
'a' could be 'an' and 'an' is located in the answer.
'rubbish' could be 'dust' (dust is a kind of rubbish) and 'dust' is found within the answer.
A single letter 'm' remains which might be clued in a way I don't understand.
This explanation may well be incorrect...
'to' is the link.
Can you help me to learn more?
(Other definitions for dustman that I've seen before include "My old man's occupation" , "Garbage collector" , "Bin emptier" , "I clear what's left" , "Refuse collector" .)