A Shropshire vicar has helped Hollywood actor Michael Sheen investigate historic toxic waste dumping for a new BBC documentary series.
Rev Paul Cawthorne, priest in charge of churches in the Hadnall area, is also a long-time environmental campaigner. He has spent two decades investigating former landfill sites, including Stoney Hill near Telford, where Monsanto legally dumped chemical waste during the 1980s.
"When I found out about the Monsanto chemical dumping at Stoney Hill, I next identified Sutton Walls in Herefordshire, then Cefn Mawr in north Wales," he told the BBC.
Cawthorne later investigated other sites across south Wales, saying they required further testing.
He said dangerously high levels of polychlorinated biphenyls (PCBs), toxic chemicals which persist in the environment, were found at nine of the 10 sites examined for the BBC's Buried radio series.
"The results at some were literally off the scale and will have a big impact in professional circles, assuming they cannot continue to try to ignore them now," he added.
Rev Cawthorne is now calling for a fresh statutory investigation into Stoney Hill.
Telford and Wrekin Council said there was "no evidence" toxic materials were tipped at the site and that regular testing had found no cause for concern.
The series will be released on 17 August.
