Introduction

Nearly 3 million nonfatal workplace injuries and illnesses were reported by private industry employers in 2012. This resulted in an incidence rate of 3.4 cases per 100 equivalent full-time workers according to estimates from the Survey of Occupational Injuries and Illnesses (SOII) conducted by the U.S. Bureau of Labor Statistics. The rate reported for 2012 continues the pattern of statistically significant declines that, with the exception of 2011, occurred annually for the last decade [US Department of Labor 2012].

Primary care providers see an estimated 80% of occupational and environmental-related illnesses. The work history represents the primary tool for recognizing work-related medical injuries and diseases [Thompson et al. 2000].

Part 2 of the Exposure History Form is a comprehensive inventory of hazardous exposures in the patient's present and past occupations.

In evaluating Part 2 of the form, the clinician should note every job the patient has had, regardless of duration. Information on part-time and temporary jobs could provide clues to toxic exposure. Details of jobs may reveal exposures that are not expected based on the job titles. Asking if any processes or routines have been changed recently can be helpful. Military service may have involved toxic exposure.

Scenario 2

• 52-year-old male who owns a commercial cleaning service
• Chief complaints: headache and nausea

Scenario 2 involves another instance of a 52-year-old male who is brought in by his wife to see his primary care physician for an evaluation.

He has been in excellent health until approximately 1 week ago, when he began staying up later and later at night according to the wife. She was not too concerned until he began awakening her to talk about the "revolutionary" new ideas he had about creating an international, commercial cleaning service. She notes he was "full of energy" and talked rapidly about many ideas that he had. She became quite concerned when at 3:00 A.M. (European time) her husband called the manager of the rayon mill, who was in Europe, to discuss his ideas. He then began telephoning European banks in an attempt to find partners for his business venture. When his wife confronted him about the inappropriateness of his phone calls, he became enraged and accused her of purposefully attempting to sabotage his venture.

The patient complains of recurring headaches and nausea that started approximately 1 to 2 weeks ago and of recent angina attacks. This patient is the owner of a commercial cleaning service and is extremely proud to tell the clinician he performs some of the cleaning himself.

Questioning the patient extensively about the cleaning products fails to yield any suspicious exposure possibilities. Reviewing Part 2 of the Exposure History Form, the clinician notes

• Detergents,
• Ammonia, and
• Cleansers.

Pursuance of Part 2, Work History, however, reveals a clue. The clinician's investigation follows.

Sample Dialogue

Clinician: You own a commercial cleaning service?

Patient: Yes. I've been in business for 10 years, and I'm going to be worldwide. Would you like to purchase stock in my company?

Clinician: We can discuss that a little later. Do you do the cleaning yourself?

Patient: I don't do as much as I used to. I have a crew of about 6 full-time employees. I do more managing than cleaning, but have been known to roll up my sleeves and pitch in when needed.

Clinician: You clean residences and commercial businesses?

Patient: Yes, I currently have 20 residential accounts and 15 commercial accounts, but have I told you that I will be international?

Clinician: Yes, you did, but right now I'd like to know about the commercial accounts that are local.

Patient: The local ones are downtown administrative offices for the school district, several realty offices downtown, and the business offices of the viscose rayon mill. I have 6 accounts in the Shaw Building downtown (small medical offices) and 5 retail stores in the Hilltop Mall, but I don't know why you will not listen to how I will revolutionize the commercial cleaning industry. I'm in touch with people that control the world currency markets. I know this because God spoke to me, telling me how to corner the cleaning market.

Clinician: That is interesting and I'd like to hear more after we finish covering a few more questions about your health.

Patient: Okay, I guess I can answer a few more questions...but you will want to hear about this lucrative opportunity!

Clinician: So your headaches have been occurring for about 1 week now? Have there been any changes in your routine - work or otherwise - in the last week?

Patient: I've worked more hours than usual over the last week. I've been doing a special project for the rayon mill. They built new offices. We moved all the old offices into the new building. That has entailed cleaning and moving

• Furniture,
• Files,
• Books, and
• Exhibits.

Clinician: Are any of your workers having similar symptoms?

Patient: No, nobody else has complained about feeling sick.

Clinician: What exactly do they produce at that plant?

Patient: They make viscose - transparent paper. I used to work there during summers when I was in college. It was hot, hard work. The whole place smelled like sulfur - rotten eggs. We used wood pulp cellulose, treated it with acids and other chemicals, and made cellulose filaments. I worked on the:

• Blending,
• Ripening, and
• Deaeration process.

Clinician: Can you smell the chemicals in the office building you're working in?

Patient: Some days there's a faint odor. Nothing like when I worked on the xanthating process. The business office building is on the northeast end of the complex. It's pretty remote from the processing plant.

Clinician: So how many extra hours have you worked the past week?

Patient: Only about 4 to 6 hours more per day this past week. Also, this past weekend I put in an extra 10 hours. I had to finish setting up the exhibits. I didn't trust the crew to handle the fragile exhibits, so I did the job myself. My crew is good but not as good as me.

Patient's wife: Tell the doctor about the bottle you broke!

Patient: On Friday, about 2 weeks ago, I worked late setting up a huge model of the xanthating process. It was tedious work and I was stressed by the time constraints to get the job done. I had broken a bottle from the exhibit when I disassembled the thing. I'm really not certain that I broke the bottle; it most likely was stored improperly.

Clinician: What was in this bottle you broke?

Patient: I think it was carbon disulfide. I think I might have put the broken glass and the cleanup rags on the floor of my truck. This stuff had a sweet odor.

Clinician: How did you clean it up?

Patient: I changed into some protective clothing and a face mask because my eyes and nose burned. There wasn't a lot to clean up because it seemed to evaporate quickly.

Clinician: Did you get any of the chemical on you?

Patient: I don't think any got on me when the bottle fell, but I'm not certain.

Clinician: How much of the chemical was in the bottle? Did you report the accident to anyone at the plant?

Patient: The bottle was about liter size. It wasn't full. There was only a small amount of liquid in the bottle. No, I didn't report the accident. Frankly, I cleaned it up the way I was taught when I worked at the mill before. They know that I'm good. I helped them to become the organization they are today. I'll just talk with the manager when he returns from Europe later this week.

Dialogue Analysis and Conclusion

The preceding conversation reveals a possible connection with the spill and this patient's symptoms. It warrants further investigation. The results of the patient's physical examination are normal, and the mental status exam shows symptoms and behavior that are typical of a manic episode. The patient is

• Grandiose,
• Irritable,
• Has a marked decrease in his need for sleep,
• Has pressured speech, and
• Possibly is having auditory hallucinations.

The patient identifies the chemical spilled as carbon disulfide, which is consistent with the patient's symptoms.

After obtaining permission from the patient, the clinician calls to consult with the poison control center regarding this patient's carbon disulfide exposure.

Sample Dialogue About the Call

Clinician: My patient is a contract employee at a local textile company. He thinks he broke a bottle that was labeled carbon disulfide in the process of his work. He didn't report the accident and just cleaned it up himself. I am concerned that he may be experiencing health effects from the possible exposure. He is complaining of

• Nausea,
• Headache, and
• Difficulty sleeping

• Agitation,
• Grandiose delusions,
• Pressured speech, and
• Possible auditory hallucinations.

Poison Control Center: It would not surprise me. Carbon disulfide is a dangerous substance. Strict industrial controls should be in effect to prevent exposure. This chemical can cause

• Nausea,
• Headache,
• Insomnia,
• Agitation,
• Mania, and
• Hallucinations,

• Headache,
• Fatigue,
• Unsteady gait,
• Vertigo,
• Hyperesthesia,
• Central nervous system depression,
• Garlicky breath,
• Nausea,
• Vomiting,
• Diarrhea,
• Abdominal pain,
• Coma,
• Convulsion, or
• Death.

Clinician: Can you send me information on carbon disulfide?

Poison Control Center: Certainly. I'll send you the information on carbon disulfide right away. I suggest that the accident be reported to the safety manager at the textile plant.

Dialogue Analysis and Conclusion

Consultation with the Occupational and Environmental Physician from the Poison Control Center confirms that this patient's symptoms could indeed be caused by exposure to carbon disulfide.

The clinician orders a

• CBC;
• ECG;
• Urinalysis;
• Liver, kidney, and thyroid function tests;
• Blood serology; and
• An electrolyte panel.

The clinician received a digital Material Safety Data Sheet (MSDS) on carbon disulfide (see Appendix II) from the textile plant safety manager.

The clinician reviews the Health Hazard Data section of the MSDS, and notes all pertinent information in the patient's medical record, along with the prior information sent electronically from the Poison Control Center.

Air sampling in the office in which the incident occurred reveals airborne concentrations of 0.8 parts of carbon disulfide per million parts of air (0.8 ppm). The Occupational Safety and Health Administration (OSHA) enforceable standard (permissible exposure limit or PEL) for carbon disulfide in workplace air is 20 parts per million (ppm) averaged over 8 hours of exposure. The concentrations were most likely much higher at the time of the incident 2 weeks ago. However, exposure to carbon disulfide has continued for a limited number of hours each week and the patient drives around with the contaminated rags and bottle in his truck.

Results of the laboratory tests on this patient are all within normal limits. Other employees at risk of exposure from this spill are also examined; none incurred acute exposure or suffered ill effects. Once the patient's exposure ceases he improves and experiences no further symptoms.

Progress Check