Flatulence kills folk unable to shut traps! (7)

I believe the answer is:

gasbags

'folk unable to shut traps' is the definition.
(talkative people - trap can mean one's mouth)

'flatulence kills' is the wordplay.
'flatulence' becomes 'gas' (flatulence is gas from the body).
'kills' becomes 'bags' (bag can mean to kill when hunting).
'gas'+'bags'='GASBAGS'

(Another definition for gasbags that I've seen is " Talkative people".)

I've seen this clue in The Independent.

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