The term relates to the area's notoriety for its high levels of pollution from local industry, which resulted in a thick smog that often blanketed the region.
Despite popular belief that the term originates from the 1960s, its earliest recorded use is in the 1990s, as visiting football supporters from other areas of the country began to refer to the locals as "smog monsters", which was later shortened to "smoggies".
The name was meant to refer to the heavy air pollution once produced by the local petrochemical industry,[1][2] and from Dorman Long.
[4] The term was referred to by Middlesbrough South and East Cleveland MP, Tom Blenkinsop, in the House of Commons, and was recorded in Hansard, in July 2011.
[8] Due to the rapid growth of Teesside in the 19th century, Smoggie represents an example of new dialect formation and was influenced by Northumbrian, Yorkshire and Hiberno-English.