DUST from the Armstrongs recycling plant in Horwich could make residents ill in the long term, an air quality expert claims — even though the emissions are within European regulations.

Campaigners are using the views of the American expert to back their case for tighter controls.

Dr Bill Sammons, a paediatrician from Massachusetts, reportedly said he had “real concern” about exposure to dust.

Dr Sammons has been contacted by campaigners representing protest groups in Horwich.

David Corless, who lives in Chorley New Road, near Amrstrongs, said the problem was particularly bad in warm, dry weather, when steam rises from the piles of wood and there is obnoxious.

The 74-year-old said: “There are two schools and a children’s day centre near Armstrongs and I’d be more worried about the long-term health of hundreds of children than older people like me.

“What is that smell? Is it rotting vegetation? It could be harmless. We don’t know.”

The Environment Agency has monitored dust from Armstrongs and at another site in Mossley, and said emissions at both are well within regulations.

However, Dr Sammons claimed people living near the plants could be at risk from breathing dust particles.

The World Health Organisation (WHO) has also said levels of emissions lower than those allowed in the UK can cause health problems.

It says average concentrations of the smallest pollution particles, called PM2.5, should be no more than 10 microgrammes per cubic metre, but UK standards allow up to 25.

Levels measured outside the Armstrongs are 8.8 microgrammes per cubic metre.

An Environment Agency spokesman said: “During the time in which monitoring was undertaken, levels were not found to be exceeding air quality standards set by the European Union.”

Armstrongs declined to comment.