Chrysotile asbestos, a known carcinogen, will not be added to a global list of toxic substances for at least two more years. The Rotterdam Convention, an international treaty governing trade in toxic substances, did not agree to add chrysotile, which represents 94% of world asbestos consumption, to a list of about 30 substances about which exporting countries must notify importing countries prior to shipment. "The lack of a decision at this time to list chrysotile asbestos raises concerns for many developing countries that need to protect their citizens from the well-known risks of this hazardous substance," said U.N. Environmental Program chief Achim Steiner.