Medical experts in Cornwall say there are no health risks to people living close to a china clay tip.
Researchers said waste tipping would not impact on public health
Last month Imerys was given permission to begin tipping waste at Scarcewater, near St Stephen.
The approval by county councillors caused an outcry among nearby residents, who have campaigned against the plans for more than a year.
They fear the tip will damage their health and lead to more noise.
Councillors asked the Central Cornwall Primary Care Trust to investigate any health risks associated with the development.
Researchers found that it would have no adverse impact on public health.
But they stressed that Imerys must do as much as possible to reduce dust and noise from traffic.