Which agent is associated with severe inhalational illness and protein-rich bronchial aspirates among a group of workers?

• A. Sarin
• B. Ricin
• C. VX
• D. Botulinum toxin

Answer: (B)

Ricin is the toxin at issue here. It is a plant-derived ribosome-inactivating protein, and inhalational exposure to it produces severe lung injury with rapid onset of cough, fever, dyspnea, and, in serious cases, respiratory failure. In the lungs, the damage from ricin leads to an inflammatory exudate and increased vascular permeability, so the bronchial secretions become protein-rich as plasma proteins leak into the airways. This pattern of a highly inflammatory, protein-rich airway aspirate fits ricin exposure well.

By contrast, the other agents cause different toxic effects: organophosphate nerve agents like the ones listed produce cholinergic crises with salivation, sweating, miosis, bronchorrhea, and bradycardia; botulinum toxin causes a descending flaccid paralysis without the same pulmonary exudative pattern. So the combination of severe inhalational illness with protein-rich bronchial aspirates points to ricin exposure, especially in a setting involving workers exposed to castor beans or ricin-containing materials.