Sixty Environment Agency investigators supported by Avon and Somerset Police swooped on several sites as part of Operation Durable.
The operation is a major investigation into suspected toxic waste offences by an Avonmouth based company, its Directors and senior management.
The Health Protection Agency is closely involved because of the nature of the waste.
The investigation is ongoing and expected to take many more months to complete.
Specialist Environment Agency crime staff from across England and Wales have been brought in to support given the unprecedented scale of the investigation.
Police have been deployed with EA staff to make arrests, gain access to properties and assist with collecting evidence.
The ten people arrested have been arrested have all been released on conditional bail pending further enquiries until a date in January 2013.
Andy Higham, Head of the Environment Agency’s NECT said: “The Environment Agency targets gravely negligent organisations and organised criminals who risk damaging heath, livelihoods and the environment.
“Following a covert Environment Agency investigation we worked with police to successfully bring in suspects.
“We take waste crime extremely seriously. This is a live and complex investigation, anyone with further information should contact Crimestoppers on 0800 555 111.’
Dr Isabel Oliver, Regional Director of Health Protection Agency South West, said: “The Health Protection Agency has been supporting the Environment Agency investigation into an industrial site in Avonmouth, over recent weeks.
“As further information and data become available from the EA, other partners and the company involved, we will consider any potential risk to public health and provide relevant health advice where we can.”