LAND where children play and people walk their dogs has been sealed off in a poison waste scare.

Dangerous substances, including chromium and arsenic, dumped 35 years ago, have seeped to the surface on the site of a former chemical works on the outskirts of Little Lever.

Council health officials have declared the land on Potter's Hill, off Hall Lane - just yards away from Little Lever secondary school - a health risk. Workmen have sealed off the contaminated ground.

Chromium waste pollution in the area has been a continuing problem for Bolton Council. It is a legacy of the Edmund Potter's Chemical Works, which used to be located on the site.

The land was reclaimed in 1968 by the local authority with the help of a derelict land grant.

But pollution was left in the ground - and the land has since been used as playing fields for Little Lever Secondary and Bowness County Primary schools.

Chromium is not thought to be dangerous in low doses and does occur naturally in the body.

But it can cause lung cancer and serious skin problems in high doses.

Denise Cooney, headteacher of Bowness County Primary School, said: "I am concerned that I have had no contact from the authorities about the contamination.

"Some of our children play on the parkland and I would like to think we would have been notified of any potential health risks." The head teacher of Little Lever secondary school declined to comment.

The chemical factory produced chromium salt compounds for industry from imported chromite ore from the 1880s until it closed in 1968 and its waste by-products were tipped on the site.

The chemical waste was spread over the site and was in turn covered by a layer of stone with topsoil and then grass was placed on top. The chromium has since seeped to the surface, along with nickel, zinc, arsenic, lead and copper.

Nicky Taylor, who lives yards from the site on Church Street, said: "I wouldn't let my child play on the field after hearing about this."

That part of the country park will be closed to the public for the duration of the work to clear the pollution. Similar work is being tackled on former industrial sites across the North-west.

A spokesman for Bolton Council's Commercial Services department said: "The level of contaminants present in the waste material varies throughout the site in both location and depth. Contaminant levels at the surface are considered acceptable for the current use of the site, but elevated levels of contaminants can be found in areas where there are springs carrying contaminated water from the waste and where the waste has been exposed due to erosion."

The spokesman added: "A detailed health risk study of the site has shown that by carrying out maintenance work on the ground's surface, we can keep health risks to a minimum."

Throughout the 1990s, the council fought to reduce the level of toxic waste in the ground. In 1993, the local authority received a £250,000 grant to make the former chemical works safe.

In 1995, however, chromium was again found to have seeped to the surface. Nine years later the same has happened again.

A spokesman for Bolton Primary Care Trust said: "The chemicals which may be present in puddles or on the surface of the ground could cause skin irritation and would be harmful if swallowed.

"People are advised to avoid contact with surface water and to keep pets away from puddles.

"If any skin irritation is experienced, seek medical advice.

"In the many years since this former industrial site was reclaimed as park land there have been no reported instances of any health problems."