Phosphides, toxicity

Symptoms of mild to moderate acute aluminum phosphide toxicity include nausea, abdominal pain, tightness in chest, excitement, restlessness, agitation, and chills. Symptoms of more severe toxicity include diarrhea, cyanosis, difficulty breathing, pulmonary edema, respiratory failure, tachycardia (rapid pulse), hypotension (low blood pressure), dizziness, or death. Convulsions have been reported in lab animals exposed to high concentrations of phosphine. Acute toxicity, resulting from aluminum phosphide exposure, is apparent most immediately in the heart and lungs it also may affect the CNS, liver, and kidneys. A postmortem examination of test animals revealed microscopic lesions in the outer cortex of rat kidneys exposed to 15 mg/m3, but not at lower exposure levels. All of these effects were apparently reversible following a 4-week recovery period.13-15... 

Zinc cyanide Zinc phosphide, when present at concentrations >10% Listing as toxic waste Zinc phosphide, when present at concentrations 10% Listing as a hazardous waste constituent Zinc cyanide Zinc phosphide Toxic chemical release report ng... 

The extremely toxic and flammable gas phosphine is safely and conveniently generated for the fumigation of grain in sacks or bins from 3-g tablets containing aluminum phosphide and ammonium carbamate which produce 1 g of phosphine in the presence of moisture. 

Phosphides are binary compounds containing anionic phosphorus (P ). Heavy metal, alkali, and alkaline earth metal phosphides exist but few of them are commercially important. Phosphides hydrolyze to the flammable and toxic gas phosphine (PH3). The hydrolysis reaction of aluminum phosphide is given below ... 

Research has shown that when polychlorpinen, ammonium nitrate, and superphosphate are present together in the soil, phosgene, carbon monoxide, nitric oxide, hydrochloric acid, ammonia, hydrocyanic anions, ozone, hydrogen fluoride and phosphide, etc. could appear in the air over the beet fields. Photooxidants could also appear. Airborne toxic compounds over this crop were noted in areas after precipitation with little wind, and with an air temperature of over 2CP . The combined and complex activity of pesticides and other chemical compounds led people who manually sowed beets to develop symptoms of poisoning. [21]... 

Zinc phosphide — a rodenticide — is relatively toxic when compared to elemental zinc or zinc oxide most of the biocidal action is attributed to the phosphide fraction. Acute oral LD50s for zinc... 

Moran, S. 1991. Toxicity of sodium fluoroacetate and zinc phosphide wheat grain baits to Microtus guentheri and Meriones tristrami. Bull. OEPP/EPPO Bull. 21 73-80. 

Shivanandappa, T., Ramesh, H.P., and Krishnakumari, M.K. Rodenticidal poisoning of non-target animals acute oral toxicity of zinc phosphide to poultry, Bull. Environ. Contam. Toxicol, 23(4/5) 452-455, 1979. 

Rodenticides are a broad class of chemicals designed to kill mammals, particularly rats and mice. Compounds that inhibit blood clotting, anticoagulants, are commonly used to control rat populations. One of the first was warfarin, which is related to the plant-derived coumadin (from spoiled sweet clover). In the 1950s rats developed resistance to warfarin, which prompted the development of more potent anticoagulants. Other rodenticides include fluoroacetic acid and zinc phosphide (very toxic) and thiourea-based compounds. The primary alternative to using rodenticides is trapping. 

Once mineral-bound aluminum is recovered from ores, it forms metal complexes or chelates. Examples of the different forms of aluminum include aluminum oxide, aluminum chlorhydrate, aluminum hydroxide, aluminum chloride, aluminum lactate, aluminum phosphate, and aluminum nitrate. The metal itself is also used. With the exception of aluminum phosphide, the anionic component does not appear to influence toxicity, although it does appear to influence bioavailability. Aluminum phosphide, which is used as a pesticide, is more dangerous than the other forms however, this is because of the evolution of phosphine gas (a potent respiratory tract and systemic toxin) rather than to the exposure to aluminum. 

No aluminum-related deaths in healthy humans have been reported after oral exposure. One aluminum compound that can be life threatening to humans is aluminum phosphide, a grain fumigant. Accidental or volitional ingestion (to commit suicide) of large amounts has caused death (Chopra et al. 1986 Khosla et al. 1988). The toxicity from this compound is due to the exposure to phosphine gas which is produced in the gastrointestinal tract after the aluminum phosphide is ingested. 

Respiratory Effects. No studies were located regarding respiratory effects of various forms of aluminum following intermediate- or chronic-duration oral exposure in humans. Acute-duration oral exposure to aluminum phosphide has been shown to cause pulmonary edema in persons following accidental or volitional ingestion (Chopra et al. 1986 Khosla et al. 1988). The toxicity was probably due to the formation of highly toxic phosphine gas rather than to aluminum exposure. 

Toxic chemical release reporting Community right-to-know aluminum phosphide Yes 40 CFR 372.65 EPA 1995d... 

Phosphine, a highly toxic gas, is generated from phosphide. The rate of formation of phosphine (permissible exposure limit [PEL], 0.4 mg/m3) is dependent on the ambient temperature and humidity. In the presence of water (humidity) or acid, the formation of phosphine is greatly enhanced at any given temperature. Phosphine is released rapidly, and... 

Srivastava AS, Tripathi RS, Pandya RC, et al. 1971. Investigations on the toxicity of barium carbonate and zinc phosphide to field rats. In Perti SL, Wal YC, Srivastava CP, eds. International symposium on bionomics and control of rodents. Proceedings and recommendations of the symposium. Kanpur, India Science and Technology Society, 80-83. 

The phosphide must be protected, from moist air, since it reacts readily with moisture to produce phosphine. Care must always be taken to avoid inhalation of the very toxic phosphine gas. 

The magnesium phosphide that is subsequently formed can react with atmospheric moisture to form phosphine, PH3 which is toxic ... 

Non-oxide ceramic nanomaterials, such as carbides, nitrides, borides, phosphides and silicides, have received considerable attention due to their potential applications in electronics, optics, catalysis, and magnetic storage. In contrast with the traditional processes, such as solid state reactions, CVD, MOCVD and PVD, which involve using high temperatures, toxic organometallic precursors, or complicated reactions and posttreatments, solvothermal method is a low temperature route to these materials with controlled shapes and sizes. 

Alumtnum phosphide, hke aluminum nitride, reacts with moisture but in this case the gaseous product is phosphine, PH3, a very toxic gas. For this reason, AlP is used as a fumigant to control insects in stored products such as raw agricultural products, animal feeds, processed foods (for example, flour and sugar), tobacco, wood, paper, leather, hair, and feathers. It is also used for control of rodents such as rats, mice, squirrels, and gophers in and around mills, food processing plants, warehouses and silos, and in rail cars, ships, and shipping containers. 

Toxic anions such as nitrates (III), nitrates(V), phosphides and oxalates, isolated by dialysis... 

Pesticide toxicity is common in humans as well as in animals. The common pesticides that cause nephrotoxicity include paraquat, diquat, and zinc phosphide. 

Even though phosphorus has a lower electronegativity than nitrogen, it will form phosphides (ionic substances containing the P3- anion) such as Na3P and Ca3P2- Phosphide salts react vigorously with water to produce phosphine (PH3), a toxic, colorless gas ... 

ACGIH TLV TWA 2 mg(Al)/m3 DOT CLASSIFICATION 4.3 Label Dangerous When Wet, Poison SAFETY PROFILE A human poison by inhalation and ingestion. Dangerous in contact with water, steam, or alkali it slowly yields PH3, which is spontaneously flammable in air. Explosive reaction on contact with mineral acids produces phosphine. When heated to decomposition it yields toxic POx. See also ALUMINUM COMPOUNDS, PHOSPHIDES, and PHOSPHINE. 

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