The Bad Product Awards have been announced in Sydney by an international network of consumer groups.

Several companies, including Coca-Cola, Kellogg's and Mattel have been named as the worst brands when it comes to abusing consumer rights around the world.

Kellogg's has been named for using cartoon-type characters and product tie-ins to sell unhealthy food to children, while Mattel has received an award for avoiding responsibility for an ongoing recall of millions of products.

Consumers International director general Richard Lloyd says Coca-Cola has also been named for making large amounts of money from selling back to consumers water that is taken from local and municipal supplies.

The overall winner is a Japanese company, Takeda Pharmaceuticals, for marketing sleeping drugs to children in the United States.