As for your dog bite studies, read the studies' sources carefully. Most get their data from police or media reports. Neither police nor the media are experts on dog breeds any more than the media is an expert on firearms.
That's why, instead of identifying an American Pit Bull Terrier, or an American Staffordshire Terrier, or an American Bully, or a Bullmastiff/Labrador mix, they say 'pit bull.'
My money's on American Pit Bull Terriers being the vast majority of the problem.
As the United States and many other nations deal with the issue of pit bulls and collect the data on their killing, maiming and disfiguring rate, you can call the UN to tell them that you need to explain that they are all wrong and don’t know what “pitbulls” are.