J Am Board Fam Pract: first published as 10.3122/jabfm.6.1.33 on 1 January 1993. Downloaded from The Pesticide-Exposed Worker: An Approach To The Office Evaluation

James E. Lessenger, MD

Abstract: Bflcllgroullll: Pesticide exposures have clinical, epidemiological, legal, and political ramifications that go beyond the confines of a physician's office. The examination of the employee who bas been exposed to a pesticide should be undertaken in an organized and methodical manner so 1hat specific questions of causality can be answered and treatment can be initiated. Methods: Five representative case studies illustrate different circumstances in which a pesticide injury can be seen in the office setting. Results IIIUl CtmcIIlSlons: A wide range of pesticides is used in business and home, and the dangers of misdiagnosis, maldiagnosis, underdiagnosis, and overdiagnosis are espedally common given the variety of chemicals used. The exposed employee must be removed from the source of exposure. Complete decontamination is a primary concern, and patients with unstable vital signs will need to be hospitalized. A methodical office examination, however, can be carried out on many exposed employees. A detailed description of the circumstances of the exposure should be elicited, and the chemical implicated in the exposure should be researched. A pesticide exposure is a sentinel event in the life of a patient and also sugests that other employees can be exposed. Such an exposure needs to be carefully assessed and documented, and proper treatment must be rendered. Further, the exposure can represent the first of many other exposures 1hat might or might not be reported. Proper notification of authorities can limit exposures before they become severe. (J Am Board Fam Pract 1993; 6:33-41.)

Concerns about pesticide exposures have become Second, many state public health laws require common in our working society. The family phy­ that pesticide exposures be reported in a timely sician often is the first professional to see a person manner. An accurate database must be established who could have been exposed to pesticides. That so state authorities can perform accurate epi­ http://www.jabfm.org/ physician must perform a thorough examination demiologic studies. to determine whether the symptoms are due to Third, the exposed individual could be ex­ pesticides and map the plan of treatment. tremely anxious and frightened. The news media A precise diagnosis, appropriate work-up, and have exposed the employees and the general pub­ adequate treatment of a pesticide injury by the lic to both fact and alarmist fiction about pesti­ first physician who sees the pesticide-injured em­ cides. The employee will need reassurance that he on 27 September 2021 by guest. Protected copyright. ployee is important for five reasons. First, it is or she will probably not have any long-term re­ essential that the employee receives treatment to sidual effects from this exposure or a professional alleviate the signs and symptoms caused by the statement as to what problems the employee can injury. This treatment must also be aimed at re­ expect. turning the employee to work, when possible, and Fourth, workers' compensation carriers and the assuring that there are no long-term residual ef­ workers' compensation system require timely, ac­ fects. Further, any long-term residual effects must curate, and complete reports. The carrier and em­ be documented so the patient can receive adequate ployer also need to be assured that the employee compensation. really has a pesticide injury and is neither imagin­ ing it nor attributing symptoms from another dis­ ease process to a pesticide exposure. Workers' Submitted, revised, 25 August 1992. compensation payments for permanent and tem­ From a private practice, Porterville, CA Address reprint re­ porary disability will depend hu-gely on the reports quests to James E. Lessenger, M.D., Morinda Medical Group, 841 West Morton Street, Porterville, CA 93257. of the treating physician. The first examination by

Pesticide-Exposed Worker 33 J Am Board Fam Pract: first published as 10.3122/jabfm.6.1.33 on 1 January 1993. Downloaded from the physician is the most important because it linesterase levels were normal. WIthin 2 days, provides an opportunity to describe the mecha­ however, her serum cholinesterase levels began to nism of injury, the symptoms, and the medical drop, but they remained within normal levels. Her history without the embellishments that often de­ rash cleared in 1 week, and she returned to work velop as time elapses. 1 week after the incident. The patient was seen Fifth, pesticide injuries can result in litigation 3 weeks after the exposure, and her physical ex­ in personal injury and workers' compensation amination was entirely normal. The case was closed. courts. For forensic purposes, an acceptable medi­ At the time of the incident the patient was lac­ cal opinion requires a reasonable medical prob­ tating and had breast fed her baby while in the ability of exposure that must be clearly separated office waiting room at her first visit. She had taken from mere possibilities and speculations. Fraud her child with her to the fields and was breast must be documented very carefully, and true pes­ feeding the child on breaks while working. She ticide exposure needs to be separated from illness was told to stop breast feeding, and her baby was from other causes. switched to bottle feedings. The baby, a 4-month-old boy had no rash or Case Reports any abnormalities whatsoever on physical ex­ Five representative cases are presented to illus- amination. We elected not to measure his choli­ trate important aspects in the work-up and treat­ nesterase activity levels because of the relatively ment of pesticide exposures. The patients resided large amount of blood that would be necessary, in the San Joaquin Valley of California, an area of and because results of the physical examination intense agriculture and pesticide use. were normal. The child was monitored weekly by physical examination for 1 month after the expo­ CAse 1 sure and findings were normal. A 31-year-old-woman came to the office com­ A report to the county health department was plaining of nausea, vomiting, headaches, an made using a facsimile (fax) machine, and a tele­ erythemic pruritic rash over her entire body, and a phone follow-up made sure the fax was received; sour taste in her mouth. later a written report was sent by registered mail. This case resulted from an incident in which The following day investigators from the Tulare 5 employees were exposed and is representative of County agriculture commissioner's office investi­

the other 4 persons. The farm laborers were work­ gated the incident, and full cooperation was http://www.jabfm.org/ ing a field inJune 1991 when they became ill. The provided. supervisor later learned that an adjacent field had All 5 employees were removed from work un­ been sprayed the evening before with a mixture of til symptoms and signs had resolved. Serial cho­ Omite CWand Guthion (azinphos, a wide-range linesterase activity levels were measured to watch cholinesterase-inhibiting organophosphate insec­ for a delayed drop in erythrocyte cholinesterase ticide). Drifting had occurred from the sprayed activity levels. The cases were not closed on these field into the adjacent field, where the employees workers until 1 month after the incident to be sure on 27 September 2021 by guest. Protected copyright. worked the next morning. AIl 5 employees came to that all signs and symptoms had resolved and the the physician's office with their immediate super­ patients had no residual effects. visor as well as the owner of the company. The patient's blood pressure was 140/82 CAse 2 mmHg and her pulse was 82 beats per minute. A 55-year-old man was sent to the office by his Her physical examination was entirely normal employer after he developed an intensely pruritic with the exception of a macular papular rash over rash on his arms. The patient denied any nausea, her entire body. Blood was drawn to measure vomiting, double vision, .blurred vision , or dizzi- cholinesterase activity levels and for a complete ness. A complete history and physical examination blood panel, and the patient was sent home to were performed, the findings of which were non­ bathe and change her clothes. remarkable. His pulse rate was 72 beats per min­ When the patient was seen later that same day ute, his blood pressure was 150/86 mmHg, and he for an examination, her headache had decreased, had an erythemic macular papular rash, as well as and she was feeling better. Her initial blood cho- secondary excoriations, covering his arms. Results

34 JABFP Jan.-Feb.I993 Vol. 6 No.1 J Am Board Fam Pract: first published as 10.3122/jabfm.6.1.33 on 1 January 1993. Downloaded from of a complete blood panel and serum and erythro­ Case 4 cyte cholinesterase activity levels were normal. A 27-year-old man who was referred by his em­ This patient had been working with a crew of ployer stated that he had been exposed to and was more than 30 employees, and he was the only consequently ill from pesticides and intended to one who developed a rash. A telephone call to sue the employer, the pesticide manufacturer, and the employer revealed that the only pesticide used the examining physician. This patient had became on the grapes where this employee was work­ ill, experiencing nausea, vomiting, severe pound­ ing was sulphur, which had been applied about ing headaches, and dizziness every Monday when 3 weeks earlier. In questioning this employee, he he went to work; and during the course of the admitted that he had had some problems with week he felt progressively better. He experienced rashes to sulphur in other fields but had just episodes of double vision but denied any rash. "shined it off." Physical examination was entirely normal with the The patient was removed from work for 1 week exception of injected sclera and a slight tremor. until his rash cleared. He was treated with oral and His cholinesterase activity levels and the results of topical steroids, and a report was made to the laboratory tests were normal. health department. "When he returned to his job, "When telephoned, his employer said that no his employer was advised to keep him away from other employee in a 4-man crew was ill, nor was sulfur residues in the future. The employee, how­ the employer himself, who worked extensively ever, quit and took a position with another com­ around the fields. The fields had not been sprayed pany working among fields where sulfur had been with any chemicals whatsoever for the 3 weeks used. The employee stated that farm labor was the before the patient came to the office. only occupation in which he could earn a living. With this knowledge the employee was ques­ The case was closed 1 month after the exposure. tioned again, and he admitted to extensive ha­ bitual use of alcohol and illicit substances, in­ Case 3 cluding cannabis and cocaine. The diagnosis of A 26-year-old man stated he had been exposed to cocaine and cannabis habituation and alcohol­ pesticides and wanted to be removed from work ism was made, and a complete report was sent to for 1 month because of this pesticide exposure. the workers' compensation carrier. The patient complained of itching and a rash on his face but denied any other health problems. Cases http://www.jabfm.org/ Further history revealed that the employee was A 33-year-old man came to the office complaining pulling weeds in an irrigation ditch and was of a "chemical reaction. " He gave a 3-week history slapped in the face by the foliage as he worked. of headaches, muscle aches and pains, weakness, On examination, the patient had an erythemic blurred vision, diarrhea, and lacrimation. The rash in linear streaks on his face. His history and symptoms appeared after he had welded a pesti­ physical examination were otherwise normal. His cide spraying rig. This man's job was to repair pulse was 82 beats per minute. His cholinesterase pesticide spraying rigs, and he often had to weld on 27 September 2021 by guest. Protected copyright. activity levels and results of a blood panel were broken parts. Sometimes the surfaces that he normal. welded were contaminated with pesticides. Two A telephone call to the employer disclosed that pesticides that he could recall were Lannate this employee was one of a group of 20 workers (methomyl, a cholinesterase-inhibiting carbamate, who were clearing weeds in an irrigation canal. used as a nematocide and broad-spectrum insecti­ The entire area where these employees were cide), and Carzol (chlordimeform, an acarcide and working had never been sprayed with any pesti­ insecticide). cides or herbicides. In fact, the employer was an This man also worked on the spraying rig as a "organic farmer." mixer-loader. Furthermore, he lived in a converted The examining physician went out to the area three-story water tower. His quarters were in the where the exposure occurred and found numerous second and third stories and the first story was stinging nettles. A diagnosis of stinging nettle ex­ used to warehouse chemicals, i~cluding pesticides. posure was made. The patient was given topical He estimated that more than 30 different types of steroids, and he returned to work in another field. pesticides were stored in the building.

Pesticide-Exposed Worker 35 J Am Board Fam Pract: first published as 10.3122/jabfm.6.1.33 on 1 January 1993. Downloaded from

On examination his blood pressure was 124/88 performed because of circumstances outside the mmHg, and his pulse rate was 78 beats per min­ control of the treating physician. ute. The entire physical examination was normal This single patient experienced three expo­ including his skin, which showed no rashes. sures: chronic exposure from working as a mixer­ The employee was removed from work pending loader while using inadequate protective equip­ the outcome of cholinesterase testing and a blood ment, acute exposure by welding contaminated panel. A sample of urine was also sent to a special­ spraying rigs without a protective mask, and ized reference laboratory for a complete pesticide chronic exposure from living in proximity to a screening. The employee was advised to leave his pesticide storage depot. Mandatory reporting pre­ current living quarters, and a complete report of vented further exposure of this patient by alerting this case was made to the health department. the inspectors. There was no specific treatment prescribed. As a mixer-loader the employee had a baseline Literature Review cholinesterase activity level established 1 year Maddy and associates! reviewed illness, injury, earlier. His plasma cholinesterase baseline level and death from pesticide exposure from 1949 to was 5187 mU/mL, and the exposure plasma cholin­ 1988. They found pesticide use to be extensive: esterase level was 4287 mU/mL, 82 percent of 268,749,526 kg were sold in 1988 alone. Agricul­ baseline. The erythrocyte cholinesterase baseline tural application was the largest use followed by level was 14,852 mU/mL, and the exposure cholin household, home and garden, industrial, institu­ esterase level was 11,698 mU/mL, 78 percent of tional, and structural use. During the 20 years of baseline. These values suggested both acute and data reviewed in their report, there were 48 occu­ chronic exposures. The normal laboratory values pational fatalities, primarily caused by organo­ for these tests are 2700 to 8000 mU/mL for phosphates, and 10,412 occupational illnesses and plasma and 11,100 to 17,900 m U/mL for erythro­ injuries. cyte cholinesterase. If baseline levels had not been Ellenhom and Barceloux,2 Morgan,3 and the available, subtle changes in the plasma and eryth­ World Health Organization (WHO)4 use a classi­ rocyte cholinesterase activity levels would not fication of pesticides that includes insecticides, have been discovered. herbicides, rodenticides, fungicides, agricultural A complete blood panel that included a com­ fumigants, and structural pesticides. A certain plete blood count, liver panel, renal panel, and amount of crossover occurs among these catego­ http://www.jabfm.org/ thyroid tests were normal. The urine pesti­ ries, but they serve to demonstrate the diversity of cide screening revealed 4.3 fLglL of dichlorodi­ pesticides as chemicals (Table 1). phenyl dichloroethylene (DDE), a metabolite Maddy, et al.,! Ellenhom and Barceloux,2 of chlorophenothane (dichlorodiphenyltrichlo­ Namba,5 and others7,8 have listed those occupa­ roethane, DDT). tions in which workers are at risk for exposure The employee was returned to duty 3 weeks to pesticides: applicators, emergency response later, when his symptoms had resolved and his personnel, flaggers for aerial application, pilots, on 27 September 2021 by guest. Protected copyright. erythrocyte and plasma cholinesterase activity lev­ fumigators, manufacturers, mixer-loaders, and els had returned to 82 and 123 percent of baseline. supervisors. In addition, workers in other occupa­ He was then closely monitored for the remainder tions risk exposure when buildings in which they of the spraying season. work are treated with pesticides and when pesti­ This employee brought in a list of 10 pesticides cides drift from overflights by application air­ that the spraying company had been using in the craft. The general public risks exposure from previous year and also brought in a list of 20 overflights, aerosol drifts from applicators, resi­ chemicals that had been stored in the storage dues on produce, spills, improper use of garden room below his living quarters. DDT, a chemical chemicals, and unauthorized entry into restricted banned from use for several years, was not on the fields and storage areas. list, and the laboratory reported that the value may Morgan,3 Ellenhom and Barceloux,2 and have been due to background levels seen in the Hayes9 report that the signs and symptoms of general population rather than an acute or chronic toxic reaction vary by pesticide type. Although it exposure. Further environmental testing was not is beyond the scope of this article to review the

36 JABFP Jan.-Feb. 1993 Vol. 6 No.1 J Am Board Fam Pract: first published as 10.3122/jabfm.6.1.33 on 1 January 1993. Downloaded from

Table 1. Classes of Pesticides: A Representative Ust. Class Pest Chemical Type Examples Insecticides Insects, spiders, mites Organophosphate, cholinesterase- Parathion, malathion, mevinphos inhibiting (Phosdrin), chlorphyrifos (Dursban) Carbamate, cholinesterase- A1dicarb (Temik), methomyl, inhibiting propoxur (Baygon), carbaryl Pyrethrins and pyrethroids Allethrin, permethrin, cypermethrin Organochlorines Propargite (Omite), dicofol (Kelthane) Herbicides (defolients) Plants Dipyridyls Paraquat, diquat Chlorophenoxy compounds 2,4-D, 2,4,5-T and dioxin Nitrophenolic and nitrocresolic Dinoseb, dinocap, dinitrocresol Chlorate salts, sulfonylureas, Sodium, potassium altrazine Rodenticides Mice, rats, gophers Anticoagulants Warfarin, coumafene, pindone Metal phosphides Zinc, aluminum phosphide Miscellaneous Sodium f1uoroacetate, strychnine, Vacor, Red squill Fungicides Fungi, molds Dithiocarbamates Thiram, ziram Organochlorines Hexachlorobenzene,quintozene Dicarboximides Captan, caprafol, folpet Miscellaneous ChlorothaloniJ, benomyl Fumigants Insects, molds, fungi Halogenated hydrocarbons Carbon tetrachloride, ethylene dibromide, DBCp, methyl bromide Vertebrates Oxides and aldehydes Ethylene oxide, formaldehyde, acrolein Sulfur and phosphorus Sulfur dioxide, aluminum phosphide, sulfuryl f10uride Structural pesticides Insects, molds, fungi, Organochlorines Aldrin, lindane, chlordane, heptachlor mites, vertebrates Wood preservatives Pentachlorophenol, arsenicals, creosote, borates, copper, and zinc naphthatenate Nematicides Nematodes Hydrocarbons DBCP Molluscicides Mollusks Metaldehyde Avicides Birds 4-Aminopyridine Avitrol Piscicides Fish Rotenone Nomsh Chlordimeform Ovatoxin Ovicides Eggs http://www.jabfm.org/

signs and symptoms of each class of pesticide, organophosphates affect the neuromuscular junc­ certain complaints are universal; vertigo, fatigue, tion. The route of exposure can be dermal, respi­ nausea, vomiting, rash, or blurred vision should ratory, gastrointestinal, or any combination of lead the clinician to suspect pesticide poisoning if the three. on 27 September 2021 by guest. Protected copyright. there is a complaint or possibility of exposure. Errors in diagnosis are common. He and col­ Hayes,9 Ellenhom and Barceloux, 2 and others3,4 leagues,10 writing in the People's Republic of have suggested several factors to consider when China, reviewed 573 cases of acute pyrethroid assessing a pesticide exposure: dose, contact time, poisoning reported in the Chinese medical litera­ chemical type, chemical name, and route of expo­ ture from 1983 to 1988. In this series, a number of sure. Dose can vary by concentration, both in misdiagnoses, mal diagnoses, and inappropriate the delivery container and as the chemical comes treatments were exposed. Specifically, several pa­ in contact with the person. For example, a con­ tients were overdiagnosed as having severe pyre­ centrated chemical can become highly diluted throid poisoning when they only had mild cases. when atomized for spray application. Dose also In addition, the authors described several cases in varies with contact time, i.e., the time from the which pyrethroid poisoning was misdiagnosed as actual exposure to the time of complete decon­ organophosphate pesticide PQisoning and atro­ tamination. Chemical type determines which or­ pine was inappropriately prescribed. In one case, gan system or systems are affected; for example, a patient actually died of atropine overdose.

Pesticide-Exposed Worker 37 J Am Board Fam Pract: first published as 10.3122/jabfm.6.1.33 on 1 January 1993. Downloaded from

The authors also described many cases of cult because of the many symptoms and signs. maldiagnosis in which heat stroke, respiratory in­ Although clinical response was prompt, manyex­ fection, and food poisoning were inappropriately posed workers developed mild symptoms that per­ diagnosed as pyrethroid exposure and poisoning. sisted for weeks after the incident. Agricultural A careful history and physical examination with investigators found high levels of both offending supporting laboratory tests are essential. Saun­ chemicals on the leaves of the grapes the em­ ders, et aLII reported an outbreak of dermatitis ployees had been harvesting. The blood chemical caused by Omite CR (propargil, a miticide and levels of the work crew were also high. The ex­ acaricide) exposure among 198 orange pickers posed workers had a broad-symptom complex employed by a packing house. The authors em­ that included weakness, one-sided head pressure, phasized careful documentation of re-entry times, nausea, vomiting, tightness of the chest, and i.e., the interval between spraying a field and when blurred vision. Three workers were admitted to a crew can safely enter the field. These data assist the hospital. The authors pointed out that the researchers to determine re-entry times or California reporting system resulted in the other authorities to fine applicators or gang bosses when employees being examined, and further illness and applicable. injury were avoided by decontamination and re­ The importance of reporting exposures to moval of the workers from exposure. health authorities is highlighted by the work of O'Malley and McCurdy.l2 These authors de­ Discussion scribed an incident in which a group of 3 0 migrant Given the great amounts of pesticides used in field workers employed by a grape grower in California and the large numbers of crops grown Madera County, California, were exposed to there, the experience of California can be easily Phosalone (benzophosphate), a cholinesterase- in­ applied to other states and countries. The data hibiting organophosphate used as a acaricide, presented by Maddy, et al. l were the result of an molluscicide, and fruit and nut insecticide. This extensive reporting system used in California group complained of gastrointestinal and consti­ since 1949. Other states have not had systems in tutional symptoms, among others. Many symp­ place as long, or their reporting system might not toms resolved soon after examination, but 4 pa­ be as stringent. It is believed, therefore, that their tients with severe sinus bradycardia were data most probably reflected the experience of

hospitalized with persistent problems for several workers around the world. http://www.jabfm.org/ days. All but 16 had moderate to severe inhibition The work-up of a pesticide-exposed employee of both plasma (nonspecific) cholinesterase and or an employee who thinks he or she has been erythrocyte (specific) cholinesterase levels. exposed to pesticides needs to be done in a me­ The authors called attention to other cases of thodical and thorough manner (Table 2). It is Phosalone poisoning that could have been under­ important to remove the worker from the location diagnosed because the signs and symptoms closely of exposure immediately and to keep that worker on 27 September 2021 by guest. Protected copyright. mimic gastrointestinal disease. They suggested away until symptoms have completely resolved that the rate of poisoning among agriculture and the environment in which the exposure oc­ workers can represent sentinel health events: co­ curred is rendered safe. Workers must be kept out workers should be examined to determine whether of the fields or buildings until the proper re-entry only 1 field worker or a group has been poisoned. times have elapsed, spilled chemicals are cleaned Because subacute poisoning, as well as pesticide up safely, and the area completely decontaminated. poisoning, can mimic many other diseases, field Decontamination of workers should be carried workers with poisoning could be underdiagnosed. out immediately. Ideally, worker decontamination Peoples and Maddy 13 reviewed an event in should occur on the job and should involve a thor­ which a 120-person grape-picking crew suffered ough bathing, including washing hair, and a exposure in 1979. The employees were required change of clothing. Contaminated clothing be­ to enter the field before the 30-day safety interval comes hazardous waste and must be discarded in elapsed, and the entire group became ill as a result accordance with local regulations. of exposure to Torak (dialifor) and Zolone (phosa­ An exposed worker should be sent to the emer­ lone). The management of the cases became diffi- gency department for treatment or hospitalization

38 JABFP Jan.-Feb. 1993 Vol. 6 No.1 J Am Board Fam Pract: first published as 10.3122/jabfm.6.1.33 on 1 January 1993. Downloaded from

Table 2. Office Work-up of the Pesticide-Exposed Worker.

Steps Specifics Remove from exposure 1. Remove patient from area where exposure occurred Decontamination 1. Bathing from head to toes with soap and water 2. Segregation and safe disposal of contaminated clothing, wash water, towels, etc. Transport to emergency department if 1. Appropriate emergency care patient shows hypertension, bradycardia, or shock Exposure history 1. Contact with employer 2. Material safety data sheet (MSDS) 3. Emphasis on past exposures and drug and alcohol history 4. Thorough discussion of how exposure occurred Physical examination 1. Thorough standard physical examination Laboratory studies 1. Complete blood count, renal panel, liver panel, and urinalysis 2. Cholinesterase levels, plasma and erythrocyte 3. Chest radiograph, electrocardiogram as indicated 4. Blood anellor urine chemical levels if indicated and interpretable Treatment 1. Specific antidote if available 2. Symptomatic treatment Research on pesticide used (information 1. MSDS (material safety data sheets) aids documentation if the research could 2. Reference texts (fable 3) be done prior to the physical 3. Poison control centers examination and treatment) 4. Specific telephone numbers stated on labels Work status 1. Off work until signs and symptoms are resolved and laboratory values return to normal Appropriate reports to health authorities 1. Record documentation in clinic notes Follow-up 1. Serial examinations 2. Serial vital signs 3. Serial laboratory tests In organophosphate poisonings, repeat cholinesterase tests untill~1s reach pre-established base line or plateau in the normal range 4. Serial documentation of work status

Case closure 1. Permanent and stationary, reach preinjury state ofheaJth http://www.jabfm.org/ 2. Careful documentation of residual impairments or disabilities

if there is evidence of hypotension, shock, brady­ ment or admitted to the hospital. They were doing cardia, or respiratory distress. Many exposed well, however, their pulse rates were normal, res­ workers who do not exhibit these findings usually piration rates were nonnal, and they could be on 27 September 2021 by guest. Protected copyright. do not need to be hospitalized and can be treated cared for on an out-patient basis. on an out-patient basis. Although the basic presenting complaint of all Case 1 illustrates several important points. The the cases reviewed in this article was that of a patient came to the office accompanied by her "pesticide exposure," only in the last case were supervisor and by the owner of the company. there elements of the classic SLUD syndrome The supervisor and the owner had already re­ associated with pesticide exposures (salivation, searched and found out the chemicals to which the lacrimation, urination, diarrhea). Therefore, if a employee had been exposed. The employee was clinician waits for those classic signs, many pesti­ initially examined, had blood drawn to measure cide exposures will be missed. cholinesterase activity levels, and was then sent A thorough history and physical examination of home for decontamination. If hypotension or an exposed patient is extremely important. The bradycardia had been found, or if the patients physician must document pr~isely the chemicals were otherwise dramatically symptomatic, they to which the employee has been exposed and would have been sent to the emergency depart- should obtain the material safety data sheet

Pesticide-Exposed Worker 39 J Am Board Fam Pract: first published as 10.3122/jabfm.6.1.33 on 1 January 1993. Downloaded from

(MSDS) on these chemicals. Federal law requires it can take 2 to 3 weeks to get the results from a that an employer make available to the employee reference laboratory. material safety data sheets. Sometimes, however, Many states require that pesticide exposures be an employee can be exposed to pesticides through reported. It is important to make a telephone or circumstances outside the control of the employer, fax report immediately to alert the authorities that such as occurred in case 1. If possible, the physi­ other exposed workers may yet be in the area cian should contact the person who applied the and to record on the clinic notes that such a report chemicals to get the proper chemical names and was completed. Furthermore, follow-up reports application dates. through the mail are often required. It is helpful for the examining physician to gain Treatment can vary. There are few specific some background on the pesticides in question. antidotes to toxic agents. Most employees exposed Table 3 presents a short list of references that are to pesticides do not need specific treatment be­ useful for physician and clinic offices. cause simply removing the individuals from expo­ The physician should get a thorough history of sure will cause their symptoms to resolve. Topical all toxic substance exposures including drugs and and oral steroids and antihistamines can relieve alcohol. Physical examinations should include rashes; headaches and dizziness might be best left particular attention to vital signs. Any rashes, ab­ untreated, although the patient often needs reas­ normal pupil size, and neurological findings surances that the symptoms will resolve. Serial should be carefully documented. laboratory tests and examinations might be re­ Laboratory tests should be oriented toward im­ quired for several weeks to months following the mediate diagnosis, as well as long-term follow-up exposure to document resolution or persistence of care. Although electrocardiograms and chest problems. radiographs should be reserved for those who have Regular reports to workers' compensation car­ respiratory symptoms or cardiac dysrhythmia, a riers on the employee's work status are necessary complete blood count and renal and liver panels to assure that temporary disability payments are should be done on all pesticide-exposed persons paid to the employee. The treating physician must to monitor hepatorenal and bone marrow changes. document when a case is closed and the exposed Cholinesterase activity levels should be meas­ worker has reached a preinjury state of health so ured for all individuals in whom exposure to or­ employers and workers' compensation carriers

ganophosphates or carbamates is suspected. Re­ can close the case. Documentation of permanent http://www.jabfm.org/ porting serial levels can help document an disability or impairment is also important so ap­ exposure and recovery, even if the results are re­ propriate disposition of an employee's workers' ported in the normal range,l4 compensation claim can be made. If the family Whether to perform urine tests for the exposed physician is not comfortable in making such de­ chemicals needs to be handled on a case-by-case finitive statements, appropriate consultation or basis. If the offending chemical has not been iden­ referral should be arranged. on 27 September 2021 by guest. Protected copyright. tified and if the employer, insurance company, or government body needs to have those data for s~ epidemiological or legal reasons, then it is advis­ Workers who come to the office complaining of able to perform urine pesticide screening. These a pesticide exposure require a thorough exami­ tests, however, are rarely helpful in the acute diag­ nation with special attention paid to careful nosis and treatment of pesticide poisoning because documentation. Exposed workers can be affected by the barrage of information and misinforma­ tion about pesticides reported by the media, and Table 3. Suggested Office Reference Texts. they have many legitimate concerns. Informa­ Ellenhom MJ, Barceloux DG. MediCIII Toxicvwgy. Diagnosis & tion gathered by a carefUl and detailed work-up treatment ofhuman poisl1lli1lg. New York: Elsevier, 1987. can be helpful in releasing the worker to a safe Hayes WJ. Pesticides Studied i1l Man. Baltimore: Williams & Wilkins, 1982. work etwironment and in reassuring the worker Morgan DEP. Recvgnition and Management ofPesticide that there will be no long-term impairment or Poisl1llings. 4th ed. Washington, DC: Environmental disability. If the worker suffers from long-term Protection Agency, 1989. impairment and disability, documentation to

40 JABFP Jan.-Feb.1993 Vol. 6 No.1 J Am Board Fam Pract: first published as 10.3122/jabfm.6.1.33 on 1 January 1993. Downloaded from substantiate the employee's claim is important. 6. Pesticides: health aspects of exposure and issues sur­ Epidemiological and legal investigations to im­ rounding their use. Continuing education seminar for health personnel course, syllabus and manual. prove worker safety rely on accurate and timely Berkeley: State of California, Department of Health reports from the initial treating physician. Services, Hazard Evaluation Section, 1988. 7. Warnick SL, Carter ]E. Some findings in a study of workers occupationally exposed to pesticides. Arch Environ Health 1972; 25:265-70. I am grateful to the Huffington Library of the American 8. Lessenger ]E, Riley N. Neurotoxicities and behav­ Academy of Family Physicians for research assistance and to ioral changes in a 12-year-old male exposed to dico­ Frederic Rieders, PhD, for reviewing the manuscript. fol, an organochloride pesticide. ] Toxicol Environ Health 1991; 33:255-61. 9. Hayes \V]. Pesticides studied in man. Baltimore: References Williams & Willrins, 1982. 1. Maddy KT, Edmiston S, Richmond D. Illness, in- 10. He F, Wang S, Liu L, Chen S, Zhang Z, Sun]. Clini­ juries, and deaths from pesticide exposures in Cali­ cal manifestations and diagnosis of acute pyrethroid fornia 1949-1988. Rev Environ Contam Toxicol poisoning. Arch Toxico11989; 63:54-8. 1990; 114:57-123. 11. Saunders LD, Ames RG, Knaak ]B, Jackson R]. 2. Ellenhorn M], Barceloux DG. Medical toxicology. Outbreak of Omite-CR-induced dermatitis among Diagnosis and treatment of human poisoning. New orange pickers in Tulare County, California. York: Elsevier, 1988. ] OccupMed 1987; 29:409-13. 3. Morgan DP. Recognition and management ofpesti­ 12. O'Malley MA, McCurdy SA. Subacute poisoning cide poisonings. 4th edition. Washington, DC: En­ with phosalone, an organophosphate insecticide. vironmental Protection Agency, 1989. West] Med 1990; 153:619-24. 4. Safe use of pesticides: third report of the WHO Ex­ 13. Peoples SA, Maddy KT. Organophosphate pesticide pert Committee on Vector Biology and Control. poisoning. West] Med 1978; 129:273-7. Technical report series no. 634, Geneva: WHO, 14. Coye M], Barnett PG, Midtling ]E, Velasco AR, 1979. Romero P, Clements CL, et a!. Clinical confirma­ 5. N amba T. Cholinesterase inhibition by organophos­ tion of organophosphate poisoning by serial cho­ phorus compounds and its clinical effects. Bull linesterase analyses. Arch Intern Med 1987; 147: World Health Organ 1971; 44:289-307. 438-42. http://www.jabfm.org/ on 27 September 2021 by guest. Protected copyright.

Pesticide-Exposed Worker 41