Two central figures in the bicarb scandal in Victoria have had further sanctions imposed at a show cause hearing in Melbourne.

Neither Greg Nelligan nor Denise Nelligan made any submissions at Monday's hearing after last week indicating at a directions hearing they would take no part in proceedings against them and six others.

The Nelligans were stood down from stablehand duties after charges were issued on January 9 and have now been placed under the same restrictions as disqualified persons.

They are warned off all Victorian racecourses and training premises and also banned from receiving any direct or indirect benefit from thoroughbred racing and/or breeding in Victoria.

The Racing Appeals and Disciplinary Board will begin the hearing into charges against the eight people from April 30.

After an investigation sparked by the withdrawal of Lovani from a race at Flemington in October because of a suspected race day treatment, her trainer Robert Smerdon was charged in January with offences dating back seven years.

Among the others charged are fellow trainers Stuart Webb, Tony Vasil and Liam Birchley who have all operated at some time under the Aquanita Racing banner.

Disqualified trainer Trent Pennuto along with Greg and Denise Nelligan, employees of Smerdon and former employees of Vasil, as well as another Smerdon employee Daniel Garland also face charges over the illegal race day administration of alkalising agents (bicarb) to horses.