Fumigants phosphine

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. 

Apart from the manufacture of derivatives, there are only two known uses for phosphine itself, ie, in the preparation of semiconductors and as a fumigant. 

Lord and Pawliszyn" developed a related technique called in-tube SPME in which analytes partition into a polymer coated on the inside of a fused-silica capillary. In automated SPME/HPLC the sample is injected directly into the SPME tube and the analyte is selectively eluted with either the mobile phase or a desorption solution of choice. A mixture of six phenylurea pesticides and eight carbamate pesticides was analyzed using this technique. Lee etal. utilized a novel technique of diazomethane gas-phase methylation post-SPE for the determination of acidic herbicides in water, and Nilsson et al. used SPME post-derivatization to extract benzyl ester herbicides. The successful analysis of volatile analytes indicates a potential for the analysis of fumigant pesticides such as formaldehyde, methyl bromide and phosphine. 

Colorless gas or liquid with an odor like bitter almond or peach kernels. Odor is detectable at 0.8 ppm, but some individuals are unable to detect odor at all. Used as an industrial fumigant. It is also used in electroplating, mining and in producing synthetic fibers, plastics, and dyes. Industrially, it can be found mixed with a variety of gases including carbon monoxide, cyanogen, and phosphine. 

Phosphine gas is registered in the United States for use inside food processing facilities. Currently, it is used primarily for fumigation of bulk stored grain. While there are several reports of phosphine resistance in stored product insect populations in Asia (Subramanyam and Hagstrum, 1996), there are few published data regarding resistance in the United States. 

Inhalation of phosphine released after fumigation with aluminum phosphide on a grain freighter resulted in acute illnesses... 

Fumigant -calcium cyanide as [CYANIDES] (Vol 7) -ethylene oxide as [ETHYLENE OXIDE] (Vol 9) -methyl bromide as [BROMINE COMPOUNDS] (Vol 4) -phosphine as [PHOSPHINE AND ITS DERIVATIVES] (Vol 18)... 

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. 

In in vitro studies, phosphine decreased red blood cell or plasma cholinesterase activity, and similar effects were seen in vivo in workers using phosphine fumigant (Potter et al. 

Berck B, Gunther FA. 1970. Rapid determination of sorption affinity of phosphine by fumigation within a gas chromatographic column. J Agric Food Chem 18 148-153. 

Phosphine, PH3 (bp 87.4°C)—Phosphine is a stored-grain fumigant. It is generated by the reaction of aluminum phosphide (AIP) with water vapor in the surrounding air. Its inhalation LC50 (4 hr) in rats is 11 ppm. 

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. 

Fumigation agents Ethylene oxide, methyl bromide, phosphine... 

In chronic studies with rats, exposure to aluminum phosphide fumigated chow (4.5mgm phosphine) resulted in decreases in food intake, body weight, hemoglobin, red blood cells, hematocrit, and in increases in platelet counts. Following a 4 week recovery period in many of the exposed rats symptoms were absent, suggesting apparent reversibility. Neither aluminum phosphide nor phosphine gas exhibit carcinogenic, reproductive, or developmental effects in animals. 

Phosphine is used as an insecticide for the fumigation of grains, animal feed, and leaf-stored tobacco, and as a rodenticide. Phosphine is also used as an intermediate in the synthesis of flame retardants for cotton fabrics, as a doping agent for -type semiconductors, as a polymerization initiator, and as a condensation catalyst. Phosphine is used in the semiconductor industry to introduce phosphorus into silicon crystals. 

Colourless gas that smells of decaying fish or garlic. Irritant. Grain fumigant. Rat paste zinc phosphide. Damp can produce phosphine from aluminium and zinc phosphides. Effects lung and liver damage, circulatory collapse. Green fluorescent sputum produced. 

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