Exposure of persons to phosphine gas from aluminum phosphide application to rodent burrows

An industrial hygiene study was performed monitoring levels of phosphine gas workers are exposed to when applying aluminum phosphide tablets to rodent burrows. Clothing and gloves were monitored for phosphine gas from residual dust. Air in the breathing zone was monitored with short and long term monitoring equipment. No levels of phosphine exceeding the legal permissible exposure limits (PEL) was detected and although residues were detected on clothing, the levels were usually quite low and dissipated in open air to undetectable levels within 12 to 17 hours in all but a few cases. Hand application was also compared to a mechanical (closed system) type application device which resulted in significantly lower phosphine exposure