Toxins aerosolized

In the event that dermally hazardous toxins have been released, responders should wear a Level A protective ensemble. Also, because of the extreme hazard posed by toxin aerosols to any area of cut or lacerated skin, responders should wear a Level A protective ensemble whenever there is any potential for exposure to airborne agent. 

Pierce, R. 1986. Red tide (Ptychodiscus brevis) toxin aerosols a review. Toxicon 24,955-965. 

Figure 2 This schematic diagram shows the absorption pathways and systems of distribution, metabolism, and elimination for potential toxins. Aerosols include dusts, other solid particulates (such as smoke), and liquid droplets (such as fog, mists, etc.). Distribution may involve deposition of a toxin within a target organ and/or metabolism with or without excretion of the toxin by the target organ (after Goyer and Clarkson, 2001).

The protective mask, worn properly, is effective against toxin aerosols. Its efficacy, however, depends on two factors (1) mask-to-face or hood-to-head fit and (2) use during an attack. Proper fit is vital. Because of the extreme toxicity of some of the bacterial toxins, a relatively small leak could result in a significant exposure. Eyes should be protected when possible. Definitive studies have not been done to assess the effects of aerosolized toxins on the eyes. In general, however, ocular exposure to a toxin aerosol, unless the exposed individual is near the release point, would be expected to cause few systemic effects because of the low doses absorbed. A few toxins have direct effects on the eyes, but these are generally not toxins we would expect to be used as aerosols. Donning the protective mask prior to exposure would, of course, protect the eyes. 

For the same reason that decontamination is only moderately important after individuals are exposed to a respirable toxin aerosol, medical personnel are probably at only limited risk from secondary aerosols. Because toxins are not volatile, casualties of a toxin attack can, for the most part, be handled safely and moved into closed spaces or buildings, unless they were very heavily exposed. Prudence dictates, however, that patients be handled as if they were chemical casualties or, at a minimum, that they be washed with soap and water. The risk to medical personnel is of greater concern with some agents. Secondary exposure might be a hazard with very potent bacterial protein toxins, such as botulinum toxin or the staphylococcal enterotoxins. (Note Decontamination and isolation of patients or remains could be much more important and difficult after an attack with a bacteria or virus that replicates within the body.)... 

More data are available on exposure of animals to toxin aerosols. Rhesus monkeys were exposed by inhalation to botulinum toxin, type A, in conjunction with toxoid and hyperimmune globulin efficacy trials.32 Exposure to 5 to 10 monkey LD50 (ie, 5 to 10 times the LD50 for monkeys) resulted in death... 

Botulinum toxins Toxin aerosolized or added to food or virater. Exposed to food orvirater. Exposed surfaces may be contaminated vifith toxin. Toxic dose 0.01 mcg/kg for Inhalation and 70 meg for Ingestion. Hours to a few days See p 136. Symmetric, descending flaccid paralysis with Initial bulbar palsies (ptosis, diplopia, dysarthria, dysphagia) progressing to diaphragmatic muscle weakness and respiratory arrest. Dry mouth and blurred vision due to toxin blockade of muscarinic receptors. Toxin cannot penetrate intact skin but is absorbed across mucous membranes or wounds. Treatment botulinum antitoxin (see p 420). 

Cause Colonization of immature intestinal tract Wound colonization resulting from contact with contaminated material Intestinal colonization secondary to disruption of normal intestinal flora Ingestion of preformed toxin in contaminated food products Respiratory exposure to toxin aerosols or droplets Systemic toxin uptake after therapeutic toxin administration... 

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