Could your compost kill you? Bacteria that can cause disease in humans - and even death - is present in bags of organic material

   

Five gardeners have been infected by Legionnaires’ disease linked to bags of compost.

The cases – all recorded since August – have led to warnings about handling shop-bought compost.

Scientists from the University of Strathclyde carried out tests on 22 commercial brands and found evidence of the bug in 14 of them. 

Four showed positive for a fatal strain – Legionella longbeachae.

Tara Beattie, the lead researcher, said a move away from traditional peat could be responsible. 

‘Disease causing micro-organisms are widespread in the environment, and therefore it is not too surprising that species of Legionella that can cause human disease are present in compost,’ she said.

‘Any environment where you have pathogenic bacteria could be a source of infection, and we already know that compost has been linked to human Legionella infection in Australia and New Zealand.

'Within the UK and across Europe, composts have traditionally been composed of peat, whereas sawdust and bark are more often used to produce compost in Australia and New Zealand where Legionellosis associated with compost is more common.

‘It may be that the change in composition of composts in the UK, moving away from peat-based products, could be resulting in species such as Legionella longbeachae being present in compost and therefore more cases of infection could occur.’

She suggested manufacturers might want to place hygiene warnings on compost packaging.

Over the past five years, at least one gardener has died from a Legionnaires’ infection.

Last month, health experts recommended putting warning labels on compost bags after a spate of Legonella longbeachae infections in Scotland.