CHEMICALS ON THE FARM

People often ask what to do if they think they have been exposed to herbicides or pesticides. It may be reassuring to know that few people are actually injured or killed by these chemicals. Of course, farmers do need to be aware of the dangers and be prepared for emergencies.

The wide variety of chemicals used to kill pests and weeds yields a variety of symptoms in poisoning that is dependent on the chemical, concentration, and the route of entry. Pesticides and herbicides are designed to act quickly and then to be eliminated quickly. The rapid action of these chemicals also means that mildly disturbed vision or breathing may worsen rapidly, so if, after working with pesticides, these symptoms appear, help should be sought quickly. If, after working with pesticides, a person begins to have vomiting, difficulty breathing, loss of coordination, slurred speech, tremors, hyperexcitability, or other unusual symptoms, seek emergency medical treatment, using the information on the warning label. The doctor will need to have the names and preferably the labels from the chemicals the victim has been working with, and a good idea of when they were used, for how long, and as much information about the symptoms as can be provided, especially when they occurred in relation to when the chemical was used. More detailed emergency information is in the "Chemical Emergencies" bulletin.

For non-emergencies, if you think you have had an exposure and want to know if you may get ill from it, it is important to be tested within 24 hours. For the most common chemicals, organophosphates and carbamates, tests include cholinesterase and common, inexpensive blood tests called SMAC and CBC. Other tests which may be applied depend upon the chemical. Few of these tests look for the actual presence of the toxic chemical because to do so would be prohibitively expensive. Instead these tests measure such factors as liver enzymes and blood cell counts. Since the merit of the tests is improved by having baseline values for the exposed individual, a person who uses toxic chemicals frequently may want to have baseline tests done in a period of non-exposure.

Commercial applicators of pesticides and herbicides fall under federal laws requiring training and licensing, and in some cases regular medical exams. In addition, certain "restricted use" chemicals can only be applied by persons who have completed an approved training program, even if the chemical is intended for private use. These rules are being revised and expanded.

It is a violation of law for any person to use a pesticide in a manner inconsistent with its label. Enforcement in Missouri is by the Bureau of Pesticide Control in the State Department of Agriculture. Cases of pesticide misuse or accidents should be reported to the Supervisor, Bureau of Pesticide Control, P.O. Box 630, Jefferson City, Mo. 65102, 573-751-2462.