BAGS of potentially lethal asbestos have been dumped and not removed, despite repeated calls from concerned residents.
Up to 20 bags of the toxic substance were left in Old Mill Lane, Cowley, close to Fray's River.
Residents claimed they reported the find more than a month ago to Hillingdon Council but no action was taken.
John Batten, 74, of Uxbridge Road, Uxbridge, said: "I called four weeks ago and my friend called before that. It's a disgrace.
"I've worked there for them (the council) for 48 years so I know what it's like. If it gets into the river it'll be contaminated."
Asbestos is made up of fibrous minerals, mainly calcium magnesium silicate.
Because the fibres are tiny they are easy to inhale and remain permanently in the lungs.
Dr John Rigby, 90, who also reported the bags said: "I've seen the dangers asbestos can cause.
"We asked for it to be taken away and it's still not been done. I think it's terrible. Children do play in the area - it's dangerous."
Around 3,000 people die a year from asbestos diseases like asbestosis - scarring of lung tissue, lung cancer, mesothelioma - cancer of the lining of the chest and lung - and pleural dis-ease.
It can take up to 40 years for those affected to show symptoms and there is no cure.
Councillor Keith Burrows (Con), in whose Uxbridge South ward the bags were dumped, said: "If it has been reported by residents, (then) as a ward councillor I'm very concerned that nothing has been done about it.
"If that falls into the river it could contaminate it, and we all know how dangerous asbestos can be.
"It's of particular concern if there are children playing in the area. If it's asbestos someone should have gone and had a look immediately."
Kathy Sparks, deputy director of environment and consumer protection at Hillingdon Council, confirmed reports of dumped asbestos had been made but after an inspection, workers found no waste. She added the council would be revisiting the area to check.