Ofcom has received a total of 505 complaints about the Channel 4 series less than a week after it began. Of these, 361 were made after Channel 4 broadcast an episode in which housemate Alexandra yelled abuse at a number of her fellow contestants. Hundreds more complaints have been received by Channel 4 itself.
The row kicked off after one of the contestants burned some chips. After Alex told her off, another housemate rushed to her defence, only to be branded "a prick" by Alex. A third housemate, Stephanie, then stepped in, only to be branded "plastic" by Alex and blamed for losing an earlier task.
Housemate Rachel Rice later described Alex's outburst as bullying, and Alex was called to the diary room to be warned about her behaviour.
Ofcom is looking in to the complaints and will be monitoring further output, before deciding whether to launch an official investigation.
Alex is not one of the contestants up for eviction this week, but given her unpopularity it is likely she will be voted out at the first opportunity, if Channel 4 does not respond to viewers' calls for her to be removed from the house.
When the episode was broadcast, an extra 200,000 viewers tuned in compared to the previous evening, but Channel 4 will be keen to avoid the distaste that surrounded last year's Celebrity Big Brother, when Jade Goody was accused of bullying and racist behaviour towards Bollywood actress Shilpa Shetty.
Jim Shelley, the television critic at the Daily Mirror, said of Alexandra: "This is a woman whose mindset is based on conflict, anger and being right. Previous BB hate figures like Nasty Nick or Charley Uchea have had another layer and been entertaining. But I just don't want someone like Alexandra in my living room.
"For the sake of the show and her own safety, take her out now."