What is phosphine?
Phosphine (PH3) is a gas composed by phosphorus hydride (wich official and international name is phosphane). PH3 is a colorless, flammable and very toxic gas with a fishy or garlic smell. Phosphine acts on the central nervous system and the lungs, causing a pulmonary oedema. Symptoms like weakness, vomiting, headaches and chest tightness can rapidly occur after exposure. Exposure – even brief – to high phosphine concentrations can lead to chronic neurological problems, this is why people working with or close to phosphine must be extremely cautious…
What is phosphine gas fumigation ?
Fumigation is a technical operation that consists of spraying a gas in a closed cabinet (barrel, slipway, crates, container) to eradicate vermin – often living organisms (insects, bugs, moth, rodents…) – the most common gas used being phosphine.
This method is for example mandatory for international shipping to avoid bacteriological contaminations or the indroduction of animals or insects from one continent to another. The only gases authorized by the FAO are the hydrogen phosphide or phosphine (PH3) and methyl bromide (CH3 Br).
What are PH3 exposure hazards?
Phosphine is very dangerous to humans. For example in 2010 in Netherlands two port workers were severely intoxicated, with a 5-days coma for one of them, while discharging a container coming from China that was containing a high concentration of toxic gas.
How to detect phosphine and to be protected against it ?
People who might be in contact with PH3, such as warehouse workers or customs officers, should systematically be equipped with a PH3 phosphine gas detector as personnal protective equipment. It is also highly recommended for people working in confined spaces potentially contamined by phosphine or working with this gas to wear a gas mask with a type B cartridge adapted to phosphine filtration.
To conclude, phosphine gas fumigation is a delicate operation often necessary but involving real hazards for workers, to handle with extreme precaution!