Scores of English and Welsh businesses face serious issues after changes to hazardous waste regulations.

Companies are already obliged to register with the Environment Agency (EA) before they dispose of hazardous waste - but more will be drawn into the equation, as the definition of waste has changed.

Previously exempt items, including computers and waste cooking oil and fat, have been added to the hazardous list. Companies that collect waste will also have to re-assess their processes.

The Chartered Institute of Waste Management warned businesses that a failure to comply could mean big fines. And the EA said a lot of businesses have been tardy in registering. There are exemptions for the smallest firms, but the agency has said if firms are not registered they do run the risk of warnings or prosecution if they are found disposing of hazardous waste.

"Businesses have had a general duty of care for some time to deal with waste responsibly," said BBC environment correspondent Sarah Mukherjee.

"But under the new legislation they have to have a far better idea of precisely what type of waste they're producing and what should happen to it."