Potassium silver cyanide

Amounts allowed range from 5 ppm in cucumbers, lettuce, radishes, and tomatoes, to 250 ppm in spices. EPA also requires industries to report spills of 1 pound or more of potassium silver cyanide and 10 pounds or more of hydrogen cyanide, potassium cyanide, sodium cyanide, calcium cyanide, or copper cyanide. 

Oral exposure to cyanide usually results from accidental, homicidal, or suicidal ingestion of cyanide salts. Sodium cyanide and potassium cyanide are the most frequently studied cyanide compounds. Copper cyanide, potassium silver cyanide, silver cyanide, and calcium cyanide are other compounds that humans could encounter through oral or dermal exposure. Cassava roots and certain fruit pits contain compounds that can be broken down to form cyanide. Cassava roots form the staple diet of some populations in Africa, Central and South America, and Asia. However, it must be noted that cassava roots are notoriously deficient in protein and other nutrients and contain many other compounds, in addition to cyanide, that could be responsible for some of the observed toxic effects. Thiocyanate is a metabolite of cyanide that is formed in the body after exposure to cyanide compounds. When possible, all oral exposures are expressed as mg CN/kg/day. 

During intermediate-duration exposure, discolored inguinal fur was found in rats exposed for 90 days to 14.5 mg CN /kg/day by gavage as copper cyanide (Gerhart 1987a) and to 2.6 mg CN /kg/day as potassium silver cyanide (Gerhart 1987b). 

The central nervous system is also a primary target of orally administered cyanide in animals. Tremors, convulsions, recumbency, and lethargy were observed in rats exposed to 7.8 mg CN /kg/day as potassium silver cyanide for 90 days by gavage (Gerhart 1987b). Since 28 of 40 rats died at this dose level, some of... 

Ocular Effects. Acute exposure to cyanogen gas produced eye irritation in volunteers (McNemey and Schrenk 1960). Similarly, chronic exposure to cyanide in the working environment caused eye irritation in exposed individuals (Blanc et al. 1985). In addition, exposure to potassium silver cyanide caused ocular opacity in exposed animals, but comeal opacity is also a sign of excessive exposure to soluble silver salts alone. However, when cyanide was applied to a rabbit s eye, keratitis developed regardless of the chemical form of cyanide used (Ballantyne 1983b). 

Characteristic Copper(l) cyanide Potassium silver cyanide Cyanogen Cyanogen chloride... 

Export volumes of cyanide compounds (foreign and domestic volumes combined) shown in Table 4-2 fluctuated widely over the period January 1989 and April 1994. No obvious trends were evident except for potassium cyanide, where export volumes decreased from 3.13 million pounds in 1989 to 0.46 million pounds in 1994. Export data could not be found in the available literature for calcium cyanide, potassium silver cyanide, cyanogen, or cyanogen chloride. 

Health-Based Limits for Exclusion of Waste - Derived Residues Calcium cyanide Copper cyanide Cyanogen sodium cyanide Hydrogen cyanide Potassium cyanide Potassium silver cyanide 1x1 O 6 mg/kg 2x1 O 1 mg/kg 1 mg/kg 7x1 O 5 mg/kg 2 mg/kg 7 mg/kg 40 CFR 266, App VII EPA 1991c... 

Waste code P099, potassium silver cyanide NA 0.072 mg/L ... 

List of Hazardous Substances and Reportable Quantities Ammonium thiocyanate Calcium cyanide, cyanogen chloride, sodium cyanide, copper cyanide Cyanides (soluble salts complexes) Cyanogen Potassium silver cyanide 5,000 lbs 10 lbs 10 lbs 100 lbs 1 lb 40 CFR 302.4 EPA 1985e... 

Emergency Planning - Extremely Hazardous Substances and Their Threshold Planning Quantities Potassium cyanide, sodium cyanide Potassium silver cyanide 100 lbs 500 lbs 40 CFR 355, App A EPA 1987f... 

Copper cyanide, cyanide, potassium silver cyanide, sodium cyanide... 

Gerhart JM. 1987b. Ninety-day oral toxicity study of potassium silver cyanide [KAg(CN)2] in Sprague-Dawley rats. Prepared for The Dynamac Corporation, Rockville, MD by IIT Research Institute, Chicago, IL. IITRI Project No. L06183, Study No. 4. 

The nature Of the ions.—In 1814, G. F. Parrst12 found that in the electrolysis of aq. soln. of potassium ferrocyanide the alkali accumulated about the negative pole, and ferric oxide and hydrocyanic acid about the positive pole, and the work of J. F. Daniell and W. A. Miller, and of W. Hittorf (1859), showed that double salts are of two kinds, and that in the one kind the metal is bound as a complex negative ion, and in the other it is the positive ion. For example, in the electrolysis of potassium silver cyanide, KCy.AgCy, W. Hittorf (1859) found that silver was deposited on the cathode, whereas with salts of the type AgN03 it is deposited on the anode. Hence, it was inferred that the salt ionizes KAgCy2=K,- -AgCy2 similarly,... 

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