Following the recent reports of a man dying after handling compost, is it still safe to have a compost heap in the garden?

T Dent, Suffolk

The Lancet did, indeed, report on the case of a 47-year-old man from Buckinghamshire who died of kidney failure a week after inhaling Aspergillus fumigatus spores while handling old bags of compost, leading him to develop acute aspergillosis.

These fungal spores are an essential component of composting and help organic matter from the garden to decompose, but such incidents are, thankfully, extremely rare. Indeed, a microbiologist at Wycombe hospital, where the man was taken, said he had been "extremely unlucky": "There must have been a very large number of spores which he inhaled ... He was a smoker and a welder by trade and his lungs may have been damaged. It's a very unusual thing to happen, but if people are dealing with big bags of mulch, there is a potential danger."

Earlier this year, a leading German pneumologist went as far as recommending that gardeners wear face masks when handling compost and mulch.

Jane Griffiths, sustainable waste manager at Garden Organic (formerly known as the Henry Doubleday Research Association), agrees that, when handling or turning compost, wearing a dust mask is a sensible precaution. "A compost bin should be treated with due consideration," she says. "However, this fungus should not cause anybody harm at a home-composting level."

Griffiths also recommends using a compost bin rather than a loose heap, to keep the spores contained; ensuring that the organic material inside the bin is kept moist; only adding small quantities of matter at a time; and maintaining an even, aereated mix of "green and brown" materials inside.

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