They do contain chemicals which may be irritating to some babies' skin and/or toxic in large quantities. So, yes. But if there were any solid proof that most babies are suffering as the result of the use of disposables, the diapers would probably be off the U.S. market. There's no way to protect baby from all toxins and carcinogens; but we need to keep contact to an insignificant level. Disposable versus cloth is an individual choice, as there are many factors (convenience, cost, environmental, dryness, chemicals) to consider.