Are all natural deodorants really free of harmful chemicals?

Are all natural deodorants really free of harmful chemicals?
http://this.org/magazine/2011/12/07/are-all-natural-deodorants-really-free-of-harmful-chemicals/

"Companies that produce "all natural" deodorants often sell consumers on three things: environmental sustainability, no animal testing, and no artificial colors. But is that the whole story? Often you'll also find allergens, petrochemicals, lung irritants and hormone disruptors on the product ingredient list—all chemicals that have been linked to cancers."