Can sodium benzoate give you cancer?

I don't believe it: Internet scare sites peddling "natural food" are allowed by law to make claims that any scientist will recognize as misleading. There's no shortage of benzoic acid in many fruits (famously cranberries) and it's chemically interchangeable with sodium benzoate varying only with ph. This alone should tell you that the danger is hyped -- if they believed their stuff, they'd attack cranberries.