Michael McGuffin, president of the American Herbal Products Association said that eliminating every trace of arsenic, mercury or lead from products would require "an entirely new food supply". According to McGuffin, the government and professional agencies set widely different safety standards for lead, mercury and arsenic and that while most of the products in Saper's article have lead levels that exceed California's standard, only two violate the World Health Organization's standard. A 2008 review has stated that "adverse health outcomes at blood lead levels below this threshold have been well demonstrated", and concluded that "it is increasingly acknowledged there is no threshold for the adverse consequences of lead exposure".