The Scottish Environment Protection Agency (Sepa) said leading gangsters were now muscling into "dirty money" businesses as waste crime becomes as lucrative as drugs and racketeering, but less risky.
The agency, police and prosecutors have been strengthening their capacity to challenge illegal dumpers, many on an industrial scale, over the last year, with at least one major investigation under way.
But the watchdog told the Scottish Parliament's Justice Committee ahead of a special evidence session on the issue today that the gangs "are not simply engaging in waste crime as an adjunct to other criminal business enterprises, such as money laundering of other crime activities, but as an active business enterprise through which they commit waste crime for the high profits that can be made".
Critical to this assessment has been the exchange of intelligence undertaken by the agency and police.
It added: "Analysis based on intelligence, licensing data and Sepa case reporting since January 2013 identifies approximately 20% of all serious and organised crime groups, including some of the top tier criminals in Scotland, are linked or are directly involved in businesses within the waste sector.
"It is our view the groups present a new scale of criminal intent and capability which, if not addressed, has the capacity to inflict serious and lasting harm on Scotland."
Such criminal fronts, Sepa said, "present a facade of compliance, employing professional managers and consultants to mask their activities".
The exact number of serious, organised crime gangs known to the authorities in Scotland varies but typically there are about 250-300, suggesting about 50 are involved in waste, according to Sepa.