Forthright resident reducing lead by 90 percent (5)

I believe the answer is:

vocal

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'forthright' is the definition.
(I've seen this before)

I can't explain the rest of the clue.

(Other definitions for vocal that I've seen before include "Articulate" , "Given to speech, often in protest" , "Talkative" , "(Performance of) piece that is sung" , "Audible in protest" .)

I've seen this clue in the Sydney Morning Herald.

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