Most of us don’t give a second thought to what happens to our waste once it’s been flushed away or dropped on the street, but there is a hidden army of people whose working lives are dedicated to protecting us from it. Join us for this revealing series of conversations with the unsung heroes who keep our world clean, and find out what it’s like to work on the frontline of other people's dirt.

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  Streets

  20 April. With Tony Dobbs, street sweeper.

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  Sewers

  14 May. With Rob Smith, chief flusher, Thames Water.

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  Homes

  29 June. With Monica Mulowoza, Environmental Health Officer