Lorry drivers and other transport staff are being forced to quit their jobs because of a lack of toilet facilities, according to a union.
Unite has also said that workers including bus drivers are suffering from health problems because they are required to wait hours before getting access to a toilet.
A survey of 4,000 lorry drivers by the union found that nine out of 10 said they rarely or never had access to toilet facilities during work time.
A separate study of 5,000 bus drivers suggested that most were not given a list of toilet facilities on bus routes.
Unite said it was releasing its research to mark World Toilet Day.
Assistant general secretary Diana Holland said: “Transport workers the length and breadth of the UK are being denied toilet dignity on a daily basis.
“The lack of access to toilets is simply intolerable and can and does result in our members developing severe health problems and in some cases being forced to quit their jobs due to medical conditions.”
Meanwhile, the Rail, Maritime and Transport union (RMT) said it found a “shocking” lack of facilities for transport workers, and that women and disabled people were particularly discriminated against
General secretary Mick Cash said the research painted a “horrific picture” of the industry that is “stuck in the 19th century”.
He added: “There is also very clearly blatant discrimination going on here and the bottom line is money.
“RMT will continue to fight for decent and accessible toilet facilities along with free sanitary protection for all.”
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