Toxic Fungi of Western North America

by Thomas J. Duffy, MD

Insecticides and other toxic sprays

Collectors should watch out for insecticides and sprays used to control unwanted plants. Places, such as golf courses, walkways and railroad tracks are often heavily sprayed. Most insecticides are synaptic poisons and acute reactions are much more common in children. Mushrooms from any of the above sites should probably not be given to anyone aged 10 or under. Young children may also lack the mature enzyme systems needed to break down these chemicals for elimination from the body.

The most dangerous of the insecticides available are the organophosphates. Earlier organophosphates, such as sevin and sarin, were used by Iraq in Sadam Hussein’s war against the Kurds. Organophosphates, such as chlorpyrifos, are esters of phosphorus having varying combinations of oxygen, carbon, sulfur and nitrogen attached. They inhibit cholinesterase and produce mild to severe muscarinic and nicotinic effects including headache, vertigo, nausea, blurred vision, tearing, constricted pupils, slow heart beat, muscle twitching, difficulty walking and excessive sweating and salivation. Carbamate insecticides, such as propoxur, produce similar effects, but are much less likely to be toxic. (17a) Other insecticides are likely to produce symptoms (other than possible GI effects) only with exposures to amounts far higher than found in fungi. Nonetheless, bizarre or possible neurological symptoms should prompt a consideration of insecticide poisoning. The symptoms of organophosphate and carbamate poisoning are similar to those produced by muscarine in some fungi, particularly inocybes and cltocybes. (See the muscarin group toxins.)