possible. These exposures can be as simple as inhaling the dust from a paper bag at the time of loading the hopper of an applicator or the contact on the skin from cleaning a plugged nozzle of a spray machine. We have shown contact exposure occurs in migrant workers as revealed by build up of residues in their blood (9). Such residues derive from close contact with treated soil and crops being processed by the migrant farm workers.

In addition to the symptoms just described, the 15 community studies previously mentioned have revealed that changes occur in the central nervous system as reflected by alteration in the electroencephalographic tracings, in kidney and liver functions as revealed by altered amino acid values, and phosphorus resorption indices in urine and in blood values where differences in hemoglobin and hematocrit levels have been observed in people occupationally exposed to pesticides (6,10-11).

RECENT REPORTS

In Iowa, lower activity values of serum lactic dehydrogenase have been observed in a carefully controlled study of farmers who have a high use of pesticides (12). Scientists have recognized for many years that organophosphorus pesticides inhibit cholinesterase activity with the subsequent cholinergic effects. Whether these observed conditions are prologues to chronic disease or enhance existing disease is a matter of speculative interest. The fact remains that a variety of acute illnesses and physiologic changes have been observed in farmers pursuing their usual activities in handling agricultural chemicals.

These exposures may be subtle or great. The farmer's method of handling agricultural chemicals is rooted in attitudinally conditioned action. Farmers accept the uncomfortable working conditions, the skin rashes, the headaches, and the upper respiratory effects suffered in farming as their lot in life.

The farm environment is not the safe, healthy, wholesome way of life that many believe. It is beset with infectious diseases such as brucellosis, leptospirosis, and a host of other zoonoses. Farm accidents from the chewing, biting, snapping, and twisting equipment exert their toll in diminishing the health and safety of the farmer and his family. A major concern should be exerted for the farmer and his welfare by the chemical and equipment industries and the health professions.

As a part of the workman's compensation program, California requires illness reports which encompasses about 80 percent of the state's agricultural work force (13). It is unfortunate that other states have not followed suit with such reports.

Morbidity data are difficult to obtain at best. Other sources of reporting include medical reports from the pesticide manufacturing industry or formulation plants. Workers in manufacturing are usually governed by fairly strict safety regulations. The farmer overlooks the usual safety precautions in the haste of job performance, so industrial and farm safety are not comparable. What is of importance, however, is the fact that illnesses and injuries occurring in the plants are typical of the compounds being manufactured or formulated and usually are explained by degree or duration of the worker's exposure.

NEED FOR ACTION

The first step to decrease the occurrence of illness in farmers associated with the use of pesticides is to document the incidence of cases. How to achieve documentation is not immediately clear. A concerted interdisciplinary effort to explore and improve the health and safety of farmers is one suggestion. Farmers should be encouraged to report their illnesses and use of agricultural chemicals to physicians or health agencies.

Permits for all agricultural users of pesticides is another suggestion. After an evaluation and recommendation has been made for the appropriate type of pesticide treatment, the farmer could take this permit or "prescription" to a source of supply and buy the pesticide. Copies of the permit could be submitted to the appropriate health and environmental control agencies.

Action within the scientific community is not enough. Political and social action are needed. Legislation can do much. An example is the recent federal action taken against DDT. This action states that DDT shall not be used except for control of pests of public health importance and pests subject to state for federal quarantines where applications of pesticides are made under the direct supervision of public health or state or federal quarantine officials. (PR Notice 70-19 USDA, Agricultural Research Service, Pesticides Regulation Division.) A similar fate can be forecast for all the "persistent" pesticides.

Recent legislation by the states of Florida (Ref. House Bill 3188 1970) and New York (Ref. Assembly Bill 5881-B 1970) give further evidence of things being done to control the use of pesticides. Legislation designates certain pesticides as restricted-use substances if they persist in the environment, accumulate as a pesticide or metabolic degradation product in plant or animal tissues or their products, and are not excreted or eliminated within a reasonable length of time. In addition these laws go on to state that if such a compound creates or presents a future risk or harmful effect on any organism other than the target organism the restriction of its sale, purchase, possession, or use is in the public interest. Indiscriminate use of pesticidal chemicals has been largely responsible for many of the problems that people do not attribute to pesticides. People must somehow be made to realize that pesticides are poisons and should be used in response to a specific problem and not for convenience.

Our present technologically oriented society is responsible for many of the problems such as those associated with the use of pesticides. First of all, our colleges and universities have produced narrowly educated scientists and technicians who have produced a highly sophisticated technology without considering the means of controlling it.

Industrial giants have developed highly sophisticated products and machines that are tremendously efficient in carrying out their specific purposes. These products are released to the public, and unfortunately the public lacks sufficient knowledge to understand what constitutes abuse or misuse of a product. The orientation of an industrial world toward obtaining a quick and dirty dollar has resulted in the provision of only the information required by law in the labeling of products. Therefore, if a given use is not contraindicated on the label, the public is apt to use pesticides for almost any purpose.

An informed public would help, but the most feasible solution seems to be legislation. This entails drawing up rules and regulations which control the misuse, indiscriminate use, and identification of restricted use of pesticide chemicals.

REFERENCES

1. Conley, B. E. Morbidity and mortality from economic poisons in the United States. Arch. Industr. Health 18:126-133, Aug. 1958.

2. Berry, C. M. Health hazards from agricultural chemicals. J. Iowa Med. Soc. 49:387-389, July 1959.

3. Long, K. R., and Walden, J. Preliminary Studies on Economic Poisons (Bulletin No. 4) Des Moines, Institute of Agricultural Medicine, University of Iowa, 1958.

4. Durham, W. F.. and others. Organophosphorus insecticides and mental alertness. Arch. Environ. Health 10:55-66, Jan. 1965.

5. Grob, D., and Harvey, A. M. Effects and treatment of nerve gas poisoning. Am. J. Med. 14:52, Jan. 1953

6. Metcalf, D. R., and Holmes, J. H. Toxicology and physiology; EEG, psychological, and neurological alterations in humans with organophosphorus exposure. Ann. N.Y. Acad. Sci. 160:357-365. 1969.

7. Spencer, M. C. Herbicide dermatitis. JAMA 198:1307-1308, Dec. 19, 1966. 8. Boguisky, E. Occupational Disease in California Attributed to Pesticides and other Agricultural Chemicals. Sacramento, Calif., Bureau of Occupational Health and Environmental Epidemiology, Department of Public Health, 1967.

9. Long, K. R. Iowa Community Pesticides Study. (Progress Report No. 16) 1969. (Unpublished)

10. Tocci, P. M. and others. Biochemical differences found in persons chronically exposed to high levels of pesticides. Industr. Med. 38:188-195, June 1969. 11. Long, K. R., and others. Epidemiology of pesticides in a rural area. Am. Ind. Hyg. Assoc, J. 30:298–304, May-June 1969.

12. Long, K. R., and Bonderman, R. P. Lactic and Glucose-6-Phosphate Dehydrogenase Values in Subjects Occupationally Exposed to Pesticides. (To be published)

13. West, Irma, and Milby, T. H. Public health problems arising from the use of pesticides. Residue Rev. 11:141-159, 1965.

Thimet is the registered trademark of the American Cyanamid Company. SevinR is the registered trademark of the Union Carbide Company, and DiSyston is the registered trademark of the Chemagro Corporation. Dr. Long says, "Commercial sources and trade names are provided for identification only. Their mention does not constitute endorsement by the Environmental Protection Agency or by the University of Iowa."

[Reprinted from The Journal of The Medical Society of New Jersey, May 1971, Vol. 68, No. 5, pp. 375-77]

PHYSICIAN'S PESTICIDES PRIMER*

(By Donald S. Kwalick, M.D./Trenton)

In suspected pesticide poisoning your State Department of Health offers services essential for confirmatory diagnosis. These services include:

1. Determinations of serum and RBC cholinesterase in suspected organophosphate or carbamate intoxications;

2. Analyses of serum, urine, and gastric contents for identification of various pesticides or their metabolites; and ;

3. Identification of whether unknown substances suspected of poisoning a patient contain pesticides.

In suspected pesticide poisoning, collect the following specimens as soon as possible during treatment: (1) Blood-heparinized and clotted; (2) Urine; and (3) Gastric Contents-if ingestion is suspected.

Refrigerate all specimens but don't freeze them. Telephone the Pesticide Projject-Area Code 609-292-7608, Monday through Friday, 9 a.m. to 5 p.m. After hours, call-Area Code 609-392-2020.

The New Jersey Community Study on Pesticides (hereafter referred to as the Pesticide Project) is sponsored jointly by the Office of Pesticides and Product Safety of the Federal Food and Drug Administration and the New Jersey Department of Health, and is part of a nationally coordinated study in fifteen states. The acute effects of pesticide poisonings are well understood, but the effects of long-term, low-level exposure are unknown. To determine whether chronic effects exist, the Project has selected 200 individuals (farmers, pest control applicators, aerial applicators, and formulators) who are occupationally-exposed to high levels of pesticides. If these persons do not demonstrate any effects from prolonged exposure, then the general population whose exposure is far less should show no effects. These persons are compared with a group of 50 minimally-exposed "controls" for any differences in blood and urine biochemistry, renal and liver function tests, complete blood counts, urinalyses, pesticide residues, and physical signs or symptoms. Each subject is given an annual physical examination, an electrocardiogram, and a chest X-ray.

The Pesticide Project has found, as would be expected, that persons exposed to pesticides in their occupation have higher serum residues of pesticides than general population or control individuals. For example, the mean residue for DDT in our exposed industrial population is 28.8. ppb†, while in the minimallyexposed and general population it is 4.4 ppbt. Thus far, no abnormal biochemical chronic changes have been found in the exposed individuals compared with our minimally-exposed control group. However, comparing 40 controls with 52 exposed (farmers and pest control operators) disclosed a statistically significant difference in the number of individuals with hearing and eye problems, chronic cough and sinusitis, dizziness and headaches, and hypertension.

TABLE 1.-GENERAL GUIDE FOR ESTIMATING LETHAL DOSE OF POISONOUS SUBSTANCES!

1 This table has been adapted from "Clinical Handbook on Economic Poisons,'' Hayes, W. J., Jr., U.S. Public Health Service Publication No. 476, reprinted January 1967, p. 4.

Kwalick is Director of our State Health Department's Community Study on Pest!cides. This comes from material presented as a scientific exhibit at the Annual Meeting of The Medical Society of New Jersey, Atlantic City, New Jersey, May 16-19. The work was supported by the U.S. Department of Health, Education, and Welfare; the Public Health Service; and the Food and Drug Administration.

Parts per billion

The acute toxicity of pesticides varies from very mild to extremely high. The relative differences are seen in Table I, which presents a general guide of lethal dose for any poisonous material. Many compounds are best classified by generic and/or chemical type. The most commonly used pesticides in New Jersey and their relative toxicity are presented alphabetically in Table II.

TABLE 11.-COMMONLY USED PESTICIDES IN NEW JERSEY-TYPE AND RELATIVE TOXICITY

Generic and/or chemical type

Anticoagulant rodenticides....

Arsenicals and other heavy metals (Hg, Pb, Cu).

Botanical insecticides..

Carbamates.

Common examples

Warfarin...

Arsenic, arsenic trioxide, sodium arsenite...

Cube, Derris; pyrethrum, rotenone.

Carbaryl (Sevin), Ferbam Maneb, Furan Zectan; Nabam,
Zineb.

Chlorinated Hydrocarbons........ Aldrin, Dieldrin, Endrin, Benzene hexachloride (BHC),
Chlordane; DDT, toxaphene, heptachlor, Lindane,
methoxychlor.

Acute toxicity rating

Mild-depends upon

dosage. Extremely high.

Mild.

Mild to moderate.

Very mild to high.

Herbicides (chlorphenoxy)....... 2,4-dichlorophenoxyacetic acid (2,4-D); 2,4,5-trichloro- Very mild to mild. phenoxyacetic acid (2,4,5-T); (MCPA) 2-methyl-4chlorophenoxyacetic acid.

Organophosphates..

Chlorthion, Decap thon, DDVP (Vapona), Diazinon; Malathion,
Parathion, Phosdrin, TEPP.

Moderate to extremely high.

Organophosphates have caused over 60 percent (52 of 82) of the reported pesticide poisonings. Since 1967 the number of organophosphate poisonings has greatly exceeded poisoning from other pesticides. With the decreased use of persistent pesticides (such as DDT) there will be a corresponding increase in the use of less persistent compounds such as carbamate and organophosphates. Although less persistent, the organophosphates include some of the most dangerous chemicals known to man. An increased number of poisonings with possible the use of less persistent compounds such as carbamates and organophosphates. usage unless there is stringent control on the purchase and use of these substances, and unless there is intensive education of the public and many occupationally-exposed individuals.

The pharmacology, onset, signs and symptoms, and treatment of the more common pesticide poisonings are summarized in Table III.

Many clinical effects of pesticide poisonings are similar but treatment varies. In any poisoning where ingestion is suspected, gastric lavage with several liters of water is indicated. If the patient is conscious, an emetic may be administered or sodium sulfate catharsis may be useful. Therapy should not await laboratory confirmation, but begun at the earliest suspicion.

TABLE 111.-ONSET, PHARMACOLOGY, SIGNS AND SYMPTOMS, AND TREATMENT OF COMMON ACUTE PESTICIDE POISONINGS

Atropine sulfate p.o. or i.m. 1-4 mg depending Severe cases: atropine sulfate parenterally 2-4 mg. upon severity of symptoms.