The Office of Environment, Health and Safety, UC Berkeley, rates silver iodide as a Class C, non soluble, inorganic, hazardous chemical that pollutes water and soil. It has been found to be highly toxic to fish, livestock and humans. Numerous medical articles demonstrate that humans absorb silver iodide through the lungs, nose, skin, and GI tract. Mild toxicity can cause GI irritation, renal and pulmonary lesions, and mild argyria (blue or black discoloration of the skin). Severe toxicity can result in hemorrhagic gastroenteritis, shock, enlarged heart, severe argyria, and death by respiratory depression.
Moreover, a key manufacturer of silver iodide for weather modification, Deepwater Chemicals, warns of potential health effects of silver iodide in their Material Safety Data Sheet as follows:
Chronic Exposure/Target Organs: Chronic ingestion of iodides may produce "iodism", which may be manifested by skin rash, running nose, headache and irritation of the mucous membranes. Weakness, anemia, loss of weight and general depression may also occur. Chronic inhalation or ingestion may cause a rgyria characterized by blue-gray discoloration of the eyes, skin and mucous membranes. Chronic skin contact may cause permanent discoloration of the skin. Under the guidelines of the Clean Water Act by the EPA, silver iodide is considered a hazardous substance, a priority pollutant, and as a toxic pollutant. Some industries have learned this all too well....According to the PGCD, "Every year, two viable samples of rainwater must be sent to a laboratory for analysis and in return forwarded to TNRCC to ensure that the water is not contaminating the area." This is faulty sampling and testing over a seven county area. If PGCD can not control where the seeded clouds dumps water, how can they take only two rain samples per year to test for silver concentrates of the clouds they seeded? At least it is an admission that silver toxicity is an issue. Such misleading statements based on faulty data are not uncommon to the PGCD. In 2001, rainfall amounts were grossly over inflated in multiple rain gauges. Such overstatements are to prop up the benefits of their program while denying the adverse effects.
To effectively monitor the levels of silver toxicity, at the very minimum, water samples should be taken on a monthly basis from every dam, creek, stock tank, and other water capture places in the respective district while cloud seeding is being conducted. Also, soil samples should taken. According to the Colorado National Park Service and the Federal Remediation Technologies Roundtable, the result of cloud seeding with silver iodide and run off have adverse effects on the water, soil, and flora and fauna. "Elevated silver concentrations in biota occur in the vicinities of sewage outfalls, electroplating plants, mine waste sites, and silver iodide-seeded areas." In fact, in the 1980s the CDC had hoped that silver toxicity would be reduced nationally based on a reduction of cloud seeding activity. "Fallout from cloud seeding with silver iodide is not always confined to local precipitation; silver residuals have been detected several hundred kilometers down wind of seeding events."
"Anthropogenic sources associated with the elevated concentrations of silver in nonliving materials include smelting, hazardous waste sites, cloud seeding with silver iodide, metals mining, sewage outfalls, and especially the photo processing industry." Silver leaches into groundwater, streams, soil, and the root systems of plants.
"Silver was measured in particular samples from rural and urban area both adjacent to and removed from activities such as metal smelting, refining, and silver iodide cloud seeding" and found "concentrations in precipitation resulting from seeding clouds with silver iodide were 10-450 ng/L compared with concentrations of 0-20ng/L without cloud seeding (Cooper and Jolly 1970)." That translates in 10 to 225 times greater silver concentration in those areas.