Agency refuse workers brought in to cover for a long-running strike are to be balloted for industrial action over claims of bullying and harassment.
Hundreds of members of Unite in Birmingham have been on all-out strike since March in a dispute over pay and jobs.
The threat of industrial action by agency workers hired to cover for the strikers makes a settlement to the row even further away.
Unite claimed a growing number of agency staff are refusing to cross the picket lines of striking bin workers due to “unsustainable” workloads and a bullying workplace culture at the council’s refuse department.
Unite general secretary Sharon Graham said: “The Birmingham bin dispute just keeps getting worse because of the complete and utter mismanagement and vindictive behaviour of the council.
“Government ministers and Birmingham councillors need to step in and ensure a fair deal for all Birmingham bin workers, which is the only way strikes will come to an end.”
A Birmingham City Council spokesperson said: “The council does not condone any actions which are contrary to legislation and good employment practice. Blacklisting will not be tolerated.
“A full investigation was immediately initiated. This has now concluded and has found that no blacklisting has taken place.”
The council added: “While we are disappointed the dispute has not been resolved as Unite has rejected all our offers, we are continuing to make regular waste collections as we prepare to implement the new and improved service.
“This is a service that has not been good enough for too long so it needs to be transformed to one that citizens of Birmingham deserve – we cannot delay this any longer.
“Although the industrial action continues, our contingency plan is working and we are collecting household waste as scheduled.”
