22 - Fumigants, fungicides and rodenticides

Abstract

This chapter focuses on toxicity caused by fumigants, fungicides, and rodenticides. The major form of accidental acute pesticide intoxication is contamination of the skin with subsequent absorption of the pesticide. Liquid formulations, especially those containing organic solvents, may permeate more rapidly than, for example, solid products, or those containing water. Skin damage facilitates absorption of chemicals. Direct contact of pesticides with eyes generally causes irritation, pain, excessive lacrimation, and sometimes visual disturbances. Acute work-related pesticide poisoning is a less frequent cause of admissions for possible poisoning than suicide. Especially in adults, suicide is a much more common reason for severe pesticide intoxications. Generally the exposure routes in occupational intoxications are skin, eyes, and lungs, while in suicide attempts the gastro-intestinal tract is the major exposure route. Even at lower levels of inhalational exposure of fumigant methyl bromide, signs of systemic poisoning may develop in the absence of lung damage. Hemoperfusion, chelating agents, and N-acetylcysteine have been used in the management of methyl bromide intoxications, but proved not to be beneficial. Acute toxicity can be observed after exposure to the dust or vapor of organic mercury compounds used as fungicides, causing local irritation of the skin and the mucosal membranes of eyes and airways. Treatment consists of prompt decontamination of the gastro-intestinal tract, to reduce further absorption and to limit the corrosive action on mucosal membranes.