1 the abcs of medical surveillance. 2 the role of surveillance in occupational health systematic...
TRANSCRIPT
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The Role of Surveillance in Occupational Health Systematic monitoring of health events and exposures in
working populations to prevent and control occupational hazards and their associated diseases and injuries
Essential Functions To gather information on cases of occupational diseases/injuries
and on workplace exposures To distill and analyze data To intervene on the basis of data to alter the factors that
produced health events and hazards To disseminate organized data to necessary parties: workers,
unions, employers, government agencies, the public
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Role of Medical Surveillance in Occupational Health Public Health Surveillance:
Population-based Undertaken by government agencies
Medical Surveillance: Ongoing application of medical tests and procedures to individual
workers who may be at risk for occupational morbidity to determine whether a disorder may be present
Can detect patterns of occupational illness in program participants Medical screening: If an individual/population is exposed to a
toxin with known effects and the tests and procedures are highly targeted to detect the likely presence of one or more effects in these persons
Hazard Surveillance: monitoring of exposure to chemical agents, physical hazards or radiation in the workplace
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The Occupational and Environmental History and Physical Examination Examinations:
Preplacement Periodic medical surveillance/medical screening Return to work assessments Exit examinations Evaluation for specific occupational exposures
Occupational History: List all jobs held and approximate dates of employment Significant changes in job duties; second jobs “Have you ever worked with or been exposed to any of the
following…?” Environmental history: home environs, water source, heating
source, indoor combustion sources, pets, hobbies, work of family members
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Preplacement Examinations Evolved from a “preemployment:” or exclusionary exam to
Preplacement/Postoffer Targeted examination, job focus, business necessity Americans with Disability Act 1990
“Otherwise qualified” individuals with disabilities cannot be excluded from employment if they can perform the essential functions of the job, with or without reasonable accommodations.
“Physical disability”: an impairment that substantially limits a major life activity “Disability” is defined after mitigating factors are addressed, i.e. medications,
prosthetics “Essential Job Functions”:
Fundamental – not performed as needed , or occasional; employer decision Job description – physical tasks as determined by a job analysis specialist If leaving out a certain function changes the job in a significant manner, than it
is an essential function. “Reasonable accommodations:
If a candidate is unable to perform the essential functions of the job Employers responsibility to determine undue hardship
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Preplacement Examinations Fitness for duty evaluation:
Determines whether a previously hired employee who was able to perform the essential functions of the job is still able to safety perform these essential functions.
Evaluation post clearance from PCP for non-occup issue
Examining physician should have access to the employees pertinent medical and personnel records in order to conduct evaluation If employee will not sign for release of records, may proceed with examination
If disabled or unfit for duty, document the restrictions/limitations
Employer decides if accommodation exists
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The Medical Surveillance Examination >30% of the US workforce receives periodic occupational
health examinations Screening: 2o prevention which focuses on the individual
for the early diagnosis and treatment Surveillance: 1o prevention focusing on identification and
elimination of the causes of disease; aggregates info from individuals to examine patterns within a population.
In accordance with OSHA standard Many employers conduct programs for hazards without
standards. The potential toxicity of ~80% of the chemicals used in the
workplace has not been evaluated in humans or in vivo or in vitro test systems.
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OSHA Medical Surveillance Requirements Acrylonitrile 29 CFR 1910.1045 Arsenic (inorganic) 29 CFR 1918 Asbestos 29 CFR 1910.1001 Benzene 29 CFR 1910.10288 Beryllium Federal Register 64:253:68853-68914 Bloodborne Pathogens 29 CFR 1910.1030 1,3 Butadiene 29 CFR 1910.1051 Cadmium 29 CFR 1910.1027 Cotton Dust 29 CFR 1910.1027 Diesel Exhaust 30 CFR 72 EEOC/ADA Ethylene oxide 29 CFR 1910.1047 Formaldehyde 29 CFR 1910.1048 Lead 29 CFR 1910.1025 Methylene Chloride 29 CFR 1910.1052 Noise 29 CFR 1910.95 Record Keeping 29 CFR 1904 Respirator Protection 29 CFR 1910.134 Vinyl Chloride 29 CFR 1910.1017
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Other Chemicals and Substances Acetic Acid Acrolein Asphalt/Asphalt Fume Carbon Disulfide Carbon Monoxide Ceramic Fibers Chlorine Cholinesterase-Inhibiting Substances
(Pesticides) Cyanides Cytotoxic Drugs Fluoride Gasoline Glutaraldehyde Hydrogen Fluoride Hydrogen Chloride Hydrogen Peroxide Isocyanates Malathion Manganese/Manganese Fumes
Mercury (inorganic) Metal working fluids Nickel Nitrogen dioxide Ozone Peracetic acid Phenol and phenolic compounds Proteolytic enzymes Psyllium Silica (Crystalline) Silver Sodium Hydroxide Soldering Solvents Sulfur dioxide Toluene/Xylene Triethylamine Trimellitic anhydride Zinc Oxide Fumes (Metal Fume Fever)
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Respirator Protection Standard Components of the program
All employees required to wear respirators must take part in the company’s training program prior to use, annually and with changes in workplace or type or respirator
Program administrator: Oversees hazard assessment, respirator selection, respirator care
and maintenance, medical evaluation, fit testing, employee training, respirator use, program assessment, record keeping
Nine components: Respirator selection, medical evaluation, fit testing, emergency
activities, maintenance procedures and schedules, adequacy of air quality, quantity/flow for respirators, training regarding respiratory hazards, and limitation of respirator fit/use/maintenance, evaluation of effectiveness of the program
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Respirator Protection Standard Prior to respiratory selection, employer reviews worker exposures,
job demands and potential adverse effects of interactions; focus on engineering and administrative controls
Qualitative vs quantitative testing: Qualitative: negative pressure air-purifying respirators (fit factor of 100 or
less) and all positive pressure respirators Quantitative: used for all respirators Isoamyl acetate (banana oil), saccharin or Bitrex solution, irritant smoke
( not recommended by NIOSH)
Procedures for IDLH (Immediately Dangerous to Life and Health) environment: standby personnel must be equipped with respirators and rescue equipment consider all oxygen deficient atmospheres as IDLH SCBA required for interior structural firefighting
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Respirator Protection Standard: Medical Evaluation
Recommend inclusion of questionnaire, single view chest x-ray and PFT.
Periodic examinations: usually annual questionnaire +/- PFT CXR: every 5 years or as medically indicated For workers with lesser exposures: OSHA questionnaire only and
examinations every 2 years The employer must ensure that a follow-up medical examination
is provided for an employee who gives a positive response to any question contained in Part A, Section 2, questions 1-8 Tobacco, seizures, diabetes, allergic reactions, claustrophobia,
trouble smelling odors, lung disease, CAD, Medications, Problems with respirator use. (eye irritation, skin allergies/rashes, anxiety, weakness/fatigue)
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Respirator Protection Standard: Medical Evaluation
The American National Standards Institute (ANSI), The National Institute for Occupational Safety and Health (NIOSH) and ACOEM suggest medical evaluations at time-based intervals based on worker age and the type of respirator used.
The American Thoracic Society (ATS) recommends that workers with respiratory symptoms, workers > 45 years wearing SCBA and workers > 55 years old have PFTs.
Exercise stress testing (EST): > 10 METS without EKG changes unlikely to have clinically
significant CAD American College of Sports Medicine: Prior to vigorous exercise,
EST for healthy men >40, healthy women >50, persons with 2 or more cardiac risk factors, or persons with known disease
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Respirator Protection Standard: Medical Evaluation
American Academy of Family Practice recommend exercise ECGs for jobs linked to police safety and require high cardiovascular performance.
DOT, NRC, FAA recommend screening certain classes of
workers for asymptomatic heart disease.
ANSI recommends those who use SCBA or a re-breather respiratory in strenuous work conditions for EST
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Age-based Recommended Medical Evaluation Frequency
AGE Light to Moderate Work
Strenuous work with SCBA
<35 Every 5 years Every 3 years
35-45 Every 2 years Every 18 months
>45 Every year Every year
McClellan, Schusler: Guide to the Medical Evaluation for Respirator Use. Table 3-4, p 59, 2000.
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Spirometry Interpretation –Obstructive Lung Disease Is FEV1/FVC%pred> LLN (lower limit of normal)?
YESnot obstructed; IF NO
Is FEV1%pred> LLN? YESborderline obstruction; IF NO
Is FEV1 (60%pred - <LLN)? YESMild obstruction; IF NO
Is FEV1%(41-59%pred)? YESModerate obstruction; IF NO
Is FEV1< 40%pred? YES Severe obstruction
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Spirometry Interpretation – Restrictive Lung Disease
If FEV1/FVC%pred WNL, with FVC < LLN mixed obstructive/restrictive pattern
Is FVC%pred> LLN? YES Not restricted; IF NO
Is FVC (60%pred- <LLN)? YESMild restriction; IF NO
Is FVC (51-59% pred)? YESModerate restriction: IF NO
Is FVC < 50% pred? YES Severe restriction
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Lower Limit of Normal for Spirometric Percent Predicted Values from Knudson Prediction Equation
AGE FVC FEV1 FEV1/FVC% FEF25-75
25-39 76.9% 70.3% 85.9% 55.3%
40-69 75.2% 77.9% 85.9% 59.2%
FEMALE
AGE FVC FEV1 FEV1/FVC% FEF25-75
25-39 81.1% 79.1% 86.9% 55.3%
40-69 73.4% 77.2% 86.9% 40.3%
MALE
McClellan, Schusler: Guide to the Medical Evaluation for Respirator Use. Table 3-6, p 63, 2000.
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Respirator Protection Standard:Medical Decision Making Seizures:
PCPs written opinion May be approved for respirator use if seizure free for 6-12 months
without impairment or symptoms, no med side effects May approve: History of early childhood seizure due to fever, isolated
seizure > 5years ago or multiple seizures > 10years ago without recurrence off medication
Controlled seizure activity (no seizure on/of med in the last year) PCP opinion, non IDLH environment, exam for SCBA, med eval for IDLH
Poorly controlled (changing meds, Workplace exposure to triggers, side effects from meds Medical eval, neurologist letter, accommodations or denial
DOT, NFPA 1582: epileptic conditions are disqualifying unless identifiable precipitant, normal EEG, normal neuro exam, seizure free 1 year off meds, neurologist’s statement
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Respirator Protection Standard:Medical Decision Making
Diabetes Episodic, unpredictable impairment of psychomotor abilities due
to hypoglycemia presents the greatest endocrinologic concern for respirator use
Majority of people with Type 1experience between 1-2 hypoglycemic episodes
Minimum of 17% of people receiving conventional insulin treatment have a least one severe hypoglycemia episode per year
Issues: shift work, irregular meals, erratic exercise and difficulty maintaining a regular medication schedule
Driving simulators: driving performance deteriorates significantly when blood glucose drops below 65mg/ml Impairs judgment about physical capabilities At least 50% of drivers with low BS decide to drive at least 50% of the
time
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Plastics, Rubbers and Resins:Acrylonitrile, 1,3 Butadiene, Vinyl Chloride, Carbon Disulfide Acrylonitrile
Manufacture of acrylic fibers, rubber-like materials, pesticides OSHA PEL 2ppm, 10ppm ceiling (15minutes) Health Effects
Route of exposure: inhalation and skin Potent mucous membrane irritant; skin blistering Metabolized to cyanide: cyanide/thiocyanate in
blood/urineweakness,asphyxia, death Suspected human colon/lung carcinogen
Medical Surveillance: at least annually skin, respiratory tract, GI, neurolook for nausea vomiting, dizziness,
weakness, CNS signs that may indicate exposure CXR, Occult blood for workers>40yrs Respirator program
Biological monitoring: thiocyanate levels Mean postshift urine levels of 11.4mg/l8 hr avg exposure of 4.2ppm Chronic human toxicity: 16-100ppm for 20-45 min nasal irritation, H/A ,
nausea, fatigue
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Plastics, Rubbers and Resins:Acrylonitrile, 1,3 Butadiene, Vinyl Chloride, Carbon Disulfide
1,3 Butadiene Exposure occurs primarily through inhalation during monomer/polymer production OSHA PEL 1ppm (TWA), 15 minute STEL of 5ppm, action level 0.5ppm Health Effects:
Liquidskin burns, frost bite; Gas mucous membrane irritant, blurred vision, cough, drowsiness
Anesthetic at high concentrations Human/animal carcinogens: leukemia and lymphosarcoma; male/female
reproductive toxicity and embryo toxicity in animals; infertility, miscarriage, anemia
Medical Surveillance: > PEL on 10 or > days/yr > PEL on > 30days/yr for 10 or more years > the action level on 60 or more days/yr for 10 or more years Above 10ppm on 30 or more days in any past year Any employee exposed in an emergency situation
Medical screening no later than 48 hours after the exposure CBC within 48 hours of the exposure, repeated monthly for 3 months
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1,3 Butadiene (cont)
Medical Surveillance: Health questionnaire yearly, emphasis on blood disorders Exam focused on lymphatic system, liver, spleen, skin Respirator standard CBC with diff and platelet count
Before employees assuming duties in a job with BD exposure, Every 3 years after the initial physical exam or at the discretion of
health professionals At time of reassignment to an area where exposure is below the
action level At termination of employment if 12 months have elapsed since last
physical examination
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Plastics, Rubbers and Resins:Acrylonitrile, 1,3 Butadiene, Vinyl Chloride, Carbon Disulfide
Vinyl Chloride Primary use is production of Polyvinyl Chloride OSHA PEL 1ppm (8 hr TWA); STEL 5ppm (15 minutes) Health Effects:
Historically – narcosis, acroosteolysis (resorption of the terminal phalanges) 1970s epidemiological studies showed link to hepatocellular injury and
angiosarcoma of the liver Pneumoconiosis: high dust exposure >10mg/m3
Medical Surveillance: History: alcohol use, hepatitis, exposure to hepatotoxic drugs/materials, blood
transfusions Exam: liver, spleen, kidneys, skin, connective tissues and respiratory Examine annually; if working with VC/PVC manufacturing for 10 years or
longer, must be examined every 6 months Lab findings:
Elevated liver enzymes/alkaline phosphatase, Fasting levels of serum bile acids/urinary coproporphyrins – indicators of
early chemical industry Alpha glutamyl transpeptidase level ~vinyl chloride exposure, greater
specificity Liver US – periportal fibrosis among highly exposed workers. Biomarkers: p63 and DNA adducts under investigation
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Plastics, Rubbers and Resins:Acrylonitrile, 1,3 Butadiene, Vinyl Chloride, Carbon Disulfide Carbon Disulfide (not federally mandated)
Intermediate for other chemical (I.e. carbon tetrachloride) and products (cellophane, rayon viscose fibers, adhesives, herbicides); manufacture of optical glass
OSHA PEL 20ppm (8 hr TWA); STEL 30ppm; 30minutes maximum allowable exposure 100ppm; IDLH (immediately dangerous to life and health) 500ppm
Health effects: Foul odor desensitizes olfactory system Skin and Inhalation: skin irritation, mucous membranes (esp eyes), CN deficits, peripheral
neuropathy, paresthesias, unsteady gait and dysphagia; Nerve damage does not resolve with end of exposure
Extreme intoxication – parkinsonism-like syndrome, psychosis and suicide May accelerate the development or worsen heart disease – risk decreased with removal Eyes: microaneuryms Ears: high frequency hearing loss/ vestibular symptoms of vertigo and nystagmus Effects libido; women at <10ppm menstrual abnormalities, spontaneous AB, premature
births No carcinogenicity
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Carbon Disulfide (continued)
Medical Surveillance: History/exam: eyes, skin, central and peripheral nervous systems,
CAD, liver, kidneys History and physical exam every 3-5 years
Biological monitoring: Preshift urines for 2-thiothiazolidine-4-carboxylic acid (TTCA) Spot urine of 0.95 mmol per mole of Cr proposed as a reliable
indicator of recent exposure 5mg corresponds to an 8 hr TWA
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Healthcare: Formaldehyde and Ethylene Oxide Formaldehyde
Backbone of chemical industry Tissue preservative and disinfectant; construction and insulation
materials, cosmetics, fertilizer, textiles, foundries, pesticides/fumicides, ink, photography and others
OSHA PEL 0.75ppm 8-hr TWA; STEL 2ppm (15min); Action level 0.5ppm; IDLH (Immediately dangerous to life and health) 100ppm
Health Effects: 1ppm – potent irritant of eyes, skin, mucous membranes and
respiratory tract Dermatitis, sensitization Lungs: rapid absorption and excreted as formic acid; bronchitis,
allergic/asthmatic reactions, pulmonary edema Sensitization: occupational asthma associated with formaldehyde
resin dust Probable human carcinogen – lung, nasopharyngeal, malignant
melanoma, pancreatic cancer in embalmers Neuropsychologic issues; spontaneous abortion (cosmetologists/lab
workers with use of disinfectants and formalin); delayed conception in woodworkers
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Formaldehyde (continued)
Medical surveillance Focus on respiratory, skin, eyes and mucous membranes and to
allergens/allergic reactions General medical questionnaire; exam focused on eyes, skin,
mucous membranes and upper respiratory tract Baseline PFT and annually Respirator Standard
Biological Monitoring Urinary formate: useful with ambient concentration of >1ppm Low level exposure during embalming associated with
cytogenetic changes in epithelial cells of the mouth and in blood lymphocytes; may be useful biologic monitoring
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Healthcare: Formaldehyde and Ethylene Oxide
Ethylene Oxide (ETO) Manufacture of ethylene glycol (antifreeze, polyester, film, bottle),
detergents, textile chemicals, pesticide, hospital sterilant, medical products Mostly used in closed operations (<1ppm) Potential exposure: maintenance, repair, product sampling,
loading/unloading transport tanks ~0.02% of production used for sterilization in hospitals; NIOSH
estimates that 75,000 health care workers have potential exposure to ETO.
Field surveys of hospital gas sterilizers have generally found 8 hr TWA exposures <1ppm; opening sterilizer, transfer of sterilized instruments to central supply, tank changes
OSHA PEL 1ppm TWA, 5ppm excursion limit (15min)
NIOSH: REL <0.1ppm TWA; 5ppm ceiling (10min/d)
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Ethylene Oxide (continued)
Health Effects: Ether-like odor, but odor threshold 700ppm Absorbed through skin, respiratory tract Binds to DNA; may cause cellular mutation Irritating to eyes, respiratory tract, skin, respiratory depression at
high concentrations URI irritation between 200-400ppm >1000ppm may cause H/A, nausea, dypsnea, vomiting, drowsiness,
weakness, incoordination Splashes can cause burns
Reproductive toxicity men and women: increase spontaneous AB and preterm birth
Human carcinogen-lymphatic/ hematopoietic, stomach Neuropsychiatric, neuropathy Occupational asthma
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Ethylene Oxide (continued)
Medical Surveillance Exposed at or above action level for at least 30 days during the
past year; upon termination of employment, reassigned to a work area with ETO exposure below the action level; emergency exposure of signs and symptoms
Pulmonary, hematologic, neurologic, reproductive systems Initial white blood cell count and periodically if exposure >0.5ppm
8-hr TWA or of intermittent exposures exceed 5ppm Consistent changes in CBC have not been demonstrated Can see elevated numbers of eosinophils, RBC, HCT
Biological monitoring Increased chomosomal aberrations
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Solvents/Paints Benzene
Core of aromatic hydrocarbons; Aromatics include benzene, toluene (methyl benzene), xylene
(dimethyl benzene), ethyl benzene, cumene (isopropyl benzene) styrene ( vinyl benzene)
Half of benzene used to synthesize ethyl benzene for production of styrene.
Toluene/Xylene principally used in paints adhesives and pesticides.
OSHA PEL 1ppm 8-hr TWASTEL 5ppm over 15 minute period
Action level 0.5ppm
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Benzene (continued)
Health Effects Acute anesthetic, respiratory tract irritation, dermatitis,
neurobehavioral dysfunction Benzene: bone marrow, aplastic anemialeukemia (acute neuro
behavior No evidence that substituted benzenes have any of the myelotoxic
effects. Toluene: renal tubular acidosis, cerebellar ataxia Toluene/xylene: raise auditory thresholds in animal at low level Benzene: human carcinogenicity
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Benzene
Medical Surveillance: All employees who are or may be exposed to benzene at or
above the action level for 30 days or more per year and employees engaged in certain manufacturing must have surveillance
Past exposure to benzene and other heme toxins, blood dyscrasias (hematologic neoplasms, genetic heme abnormalities), renal or liver dysfunction, medicines, previous exposure to ionizing radiation and marrow toxins.
Annual physical examination for signs related to blood disorders; CBC, WBC with differential, quantitative thrombocyte count, indices
(MCV, MCH, MCHC) Emergency exposure: provide end of shift urinary phenol within
72 hours; urine specific gravity is to be corrected to 1.024. If urinary phenol = to or > than 75mg/l, CBC, RBC count, WBC with
diff and thrombocyte count monthly for 3 months.
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Solvents/Paints Methylene chloride:
Paint remover, manufacture of urethrane film OSHA 8-hr TWA PEL of 25 ppm and STEL of 125 ppm Health effects – Inhalation hazard
CNS depression: coordination/alertness Cardiac toxicity: Metabolized to CO – susceptible individuals include
persons with heart disease and those with risk factors for hear disease
Liver toxicity Medical surveillance
At or above the action level (1/2 PEL) on 30 or more days per year or above the 8-hr TWA PEL or the STEL 10 or more days per week.
Neuro, skin, hematologic, liver disease, heart disease, risk factors for cardiac disease.
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Methylene Chloride (continued) Medical surveillance (continued)
Annual updates of the medical/work histories for each affected employee Physical examinations, including lab surveillance
45 yrs or older within 12 months of initial surveillance or any subsequent surveillance
<45 years within 36 months of initial surveillance or subsequent surveillance
If employee leaves the employers workplace to is reassigned to an area where exposure to MC is consistently at or below the action level and STEL, medical surveillance must be made available at that time if 6 months or more have elapsed since the last medical surveillance.
Must provide opinion concerning whether exposure to MC may contribute to or aggravate the employees existing cardiac, hepatic, neurology, dermal disease and whether employee has any other medical condition that would place him at increased risk of material impairment from exposure to MC
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Metals – Arsenic, Beryllium, Cadmium, Lead, Mercury (inorganic)
Arsenic Elemental, trivalent, pentavalent – most common inorganic forms Most reports of acute/chronic toxicity – arsenic trioxide
Pentavalent trivalent Arsine gas- extremely potent/acute poison; used in microelectronics and in
the manufacture of gallium arsenide substrates Arsenic trioxide/pentoxide used in pesticides Metallic arsenic – alloy for hardening lead in battery grids, bearing, and
cable sheaths Exposure: maintenance, manufacture, flu dust (smelting) Environment: average daily intake: 10-50ug/d; drinking water standard
10ppb, organic arsenic compounds present in seafood – not metabolized, excreted unchanged
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Arsenic (continued) Ingestion and inhalation; limited skin absorption Taken up by RBCliver, kidney, muscle, bone, skin, hair As: OSHA PEL and ACGIH TLV 0.01mg/m3 TWA Arsine: OSHA PEL and ACGIH TLV 0.05ppm Health Effects:
Irritation to skin, eyes, mucous membranes GI (fluid loss, bleeding) Nervous system: Neuropathies, weakness, paralysis Cardiomyopathy, peripheral vascular disease Lung Cancer, leukemia, lymphoma, angiosarcoma of the liver
Medical Surveillance: Absorbed trivalent arsenic is metabolized to dimethlarsinic acid
(DMA) and monomethylarsonic (MMA) and excreted in the urine with a half-life of 10 hrs
Organic arsenic cpds excreted unchanged in the urine
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Arsenic (continued) Medical Surveillance
Preplacement surveillance For workers exposed to inorganic arsenic for at least 30 days per year Focus on history of smoking history and evidence of respiratory disease CXR – PA view Nasal and skin exams Respiratory standard: exposed above action level (5ug/m3)
Periodic surveillance For covered employees <45 years old with < 10 years employment in areas
exceeding the action level; annual interim history For other covered employees, interim history, physical exam and lab studies
every 6 months Lab studies:
Measure DMA, MMA eliminate confusion over dietary sources or organic arsenic compounds
Nonexposed workers<10ug/g Cr Workers exposed to 0.01mg/m will have level of 50ug/g Cr
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Metals – Arsenic, Beryllium, Cadmium, Lead, Mercury (inorganic)
Beryllium Production of hard, corrosion-resistant alloys for use in the
aerospace industry; nuclear reactors, ceramics, semiconductors Mining of beryllium ore is not associated with adverse health
effects; use of beryllium compounds, especiallly beryllium oxide carries substantial risk of disease
Exposure to minute ultrafine particles, rather than total mass/dose is key factor in sensitization
OSHA PEL 2.0ug/m3;NIOSH REL not to exceed 0.5ug/m3; ACGIH TLV 0.2ug/m3
Poorly absorbed after inhalation, ingestion or skin Retained in lung, deposited in bone, liver and
spleenNoncaseating granulomas Slow renal excretion; confirms exposure, levels usually
undetectable in nonexposed individuals.
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Beryllium (continued) Health effects:
Acute exposure: irritant effects on eyes, mucous membranes, respiratory tract; tracheobronchitis, chemical pneumonitis, pulmonary edema; after skin contact irritant/allergic dermatitis, granuloma
Chronic exposure: exertional dypsnea, fatigue, wt loss, rales, lymphadenopathy, clubbing, pulmonary HTN
Lung cancer in humans; lung cancer, osteogenic sarcoma in animals Medical Surveillance
Preplacement: Medical/occupational histories: previous or anticipated exposure Respiratory standard as appropriate Physical exam: skin, eyes, respiratory tract CXR – B reader, PFT Be-induced lymphocyte proliferation (Be-LPT): confirms sensitization
Periodic: Annually for beryllium workers, every 3 years for beryllium associated workers Hx, PE, Respiratory Questionnaire Be-LPT CXR every 5 years
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Metals – Arsenic, Beryllium, Cadmium, Lead, Mercury (inorganic)
Cadmium Metal plating, solder, smelting (cadmium oxide), battery alloys, pigments,
printing, semiconductors Present in the diet (liver, shellfish, meat by-products, vegetables),
environmental exposure – exposure to cigarette smoke @ 2ug/day Absorbed primarily through ingestion; inhalation 10-40%; GI 5% Renal excretion with t1/2 of 8-30yrs cadmium nephrotoxicity OSHA PEL – 5ug/m3 at 8 hr TWA; Action level – 2.5ug/m3
Health effects: Acute inhalation: sore throat, H/A/, myalgia, nausia, fever, metallic taste
SOB, chemical pneumonitis, respiratory failure; hepatic/renal injuty Chronic exposure: proteinuria with excretion of LMW proteins (B1, B2
microglobulins) renal stones, bone pain, pulmonary fibrosis, emphysema, central/peripheral nervous system, human carcinogen (lung, GU,Prostate), reproductive effects (testicular)
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Cadmium (continued) Medical Surveillance
Preplacement:: Medical/Occupational hx: cardiovascular, respiratory,
renal,reproductive, musculoskeletal, hematopoietic Physical exam: including prostate exam for male >40 CXR/PFT – pulmonary toxicity/respirator use Kidney, liver, Hb Annual exam for employees with exposure > 30 days
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Cadmium (continued)
Actions Biological Monitoring Result
Annual biological monitoring
Medical exam every 2 year
Urine Cad < 3ug/g Cr
B2-Microglobulin < 300ug/g Cr
Cadmium in blood < 5 ug/L whole blood
Semiannual biological monitoring
Medical exam annually
Exposure assessment
Exposure control
Urine Cad 3-7 ug/g Cr
B2 Microglobulin 300-750 ug/g Cr
Cadmium in blood 5-10 ug/L whole blood
Mandatory removal
Biological monitoring every 3 months
Medical examination every 6 months
Exposure assessment
Urine cadmium >7ug/g Cr
B2-Microglobulin >750ug/g Cr
Cadmium in blood >10ug/L whole blood
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Metals – Arsenic, Beryllium, Cadmium, Lead, Mercury (inorganic) Productions of electrical equipment, instruments, medicinal/skin
care products, lubrication oils Exposure via inhalation of mercury vapor, ingestion, skin contact
with liquids or salts ACGIH TLV 0.025mg/m3
Health effects: CNS, blood, kidneys, liver, respiratory Mercury vapors: Micromercurialism – weakness, fatigue, weight loss,
mercurial “facies” (tremors), “Mad as a hatter”. Medical Surveillance
Focus medical/occupational hx: CNS, respiratory, kidneys, skin Urine Hg history of exposure Workplace monitoring – urine is first choice Normal concentrations: nonexposed <0.01mg/L whole blood; <10ug/g Cr
urine; substantial seafood consumption – high blood levels with low urine levels
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Mercury (inorganic)Medical Surveillance
Air Exposure Urine HG Level Action
>50ug/m3 >100ug/g creatinine Remove from exposure until <50
Medical exam if over 150 or if (2) consecutive levels exceed 100
Repeat measurement weekly
50ug/m3 75-100ug/g Cr Monitor weekly
Perform hygiene assessment to limit exposure
25-50ug/m3 50-75 ug/g Cr Monitor monthly 25 mg/m3 35-50ug/gCr Monitor quarterly
<25ug/m3 <35ug/g Cr Monitor semiannually
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Metals – Arsenic, Beryllium, Cadmium, Lead, Mercury (inorganic)
Lead: Storage batteries, alloys, pipes, cable sheathing solder, paints/plastics,
cosmetics, munitions, glassware, jewelry Occupational exposure is a result of a combination of inhalation and ingestion Environmental exposure: auto exhaust, near lead smelters, moonshine, acidic
foods/beverages in ceramics, herbal remedies Approximately 40% of inhaled lead oxide fume absorbed through the respiratory
tract; GI absorption 5% Greater GI absorption in infants/children Iron, Ca deficiencies and high fat diets increase GI absorption
Metabolism: Bound to RBC’s free fraction in plasma distributed to brain, kidney, liver, skin,
muscle Crosses the placenta (fetal level ~maternal levels), pregnancy mobilizes lead Bone is major site of deposition of absorbed lead Binds to sulfhydryl groups (found in hair and nails) Excreted primarily via kidney; t1/2 5-10 years
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Lead Water soluble alkyl lead compounds are readily absorbed
through skin contact, inhalation or ingestion Tetraethyl/methyl lead tri alkyl metabolites toxicity Accumulates in CNS – fat soluble Ultimately converted to inorganic lead and excreted in urine
Health Effects Acute: GI (abdominal pain, constipation, N/V tarry stools);
Neurologic manifestations of lead encephalopathy (H/A, confusion, stupor, coma, seizures); Renal failure/oliguria
Chronic: Early: Fatigue, irritability, vague GI symptoms, arthralgia/ myalgias Later: confusion, memory, distal motor neuropathy (wrist/.foot drop);
encephalopathy/seizures/coma; infertility (spermatogenesis, spontaneous AB); HTN, cardiac conduction, gouty arthritis, nephropathy
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Lead Medical Surveillance
Focus on lead exposure history, hygiene, GI, heme, renal, repro, neuro, pulmonary status (respiratory use), BP
Labs: BLL (blood lead level), ZPP, HB/HCT, Cr/UA
BLL – recent exposure (days/weeks); nonexposed: 1-5ug/dl; subtle effect on central/peripheral nervous system 30-50ug/dl
ZPP – alters heme synthesis increase ZPP Recent studies: at BLL of 17ug/dl see increase ZPP Abnormal for @120 days Represents average lead exposure for past 3 months Limited usefulness since health effects occur at much lower
levels (CDC recommends <10ug/dl for children) Chronic exposure:
K-band xray fluorescence of bone is best EDTA lead mobilization test (>350ug/L) confirms past exposure,
but not lead toxicity
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Lead Medical surveillance (continued)
Medical examinations: Yearly for BLL > 40ug/dl Prior to assignment Signs/symptoms of toxicity
Medical surveillance: Required for exposure to air level > 30ug/m3 for at least one day in 12
months BLL every 6 months if <40ug/dl BLL every 2 months if > 40ug/dl until (2) consecutive determinations
are < 40 ug/dl Monthly during medical removal
For >60ug/dl Average levels >50ug/dl Risk of health impairment May return if (2) consecutive BLL <40ug/dl
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Welding Application of heat/pressure to join metal Primarily manual arc welding used, but automation increasing Health hazards: metal fumes, particulates, gases, radiation
(infrared, UV), noise, electricity, ergonomic stress Main exposure is to iron oxidebenign pneumoconioisis Exposure to manganese, fluoride films Chromium/Nickel/manganese present in stainless steel alloys Stainless steel surface reflects UV radiation nitrogen oxide,
ozone Low hydrogen welding of stainless steel generates high
concentration of fluoride fumes, aluminum oxide formation Cadmium containing silver solder generates cadmium
oxideacute lung injury, death Soldering: low temp, generally not associated with significant
metal fumes; exposure to lead dust; Rosin- skin sensitizers, allergic dermatitis
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Welding (continued) Acute Exposure:
Photokeratitis: UVB radiation exposure for several seconds- pain, burning, grit-like feeling; conjunctival injection; punctate depressions over cornea; self-limited, resolving in several hours
Metal fume fever: i.e. Zn – benign, self limited with delayed onset of 8-12 hours; fever, chills, cough, myalgias, metallic taste
Pulmonary Upper respiratory irritation: dusts, ozone, aluminum oxide, nitrogen oxides,
cadmium oxide Asthma: chromium, nickel Acute lung injury and pulmonary edema: nitrogen oxide, cadmium oxide
Musculoskeletal trauma Chronic exposure:
Siderosis – accumulation of nonfibrogenic iron oxide particles in the lung Small increases in lung cancer – chromium and nickel in welding of
stainless steel
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Mineral Fibers: Asbestos and Man-Made Mineral Fibers (MMMF)
Asbestos Thermal and electrical insulation for fireproofing, in cement products such as pipes
and panels Significant exposure due to demolition of asbestos containing buildings Generally believed that all forms (serpentine and amphiboles) of asbestos have
these effects: Serpentine (chrysotile)
90% of asbestos found in the US On per fiber basis, highest risk of lung cancer – very long thin fibers
Amphiboles ( amosite, crocidolite, anthophyllite, tremolite) Most common are chrysotile, amosite, crocidolite
Health effects Inhalation of fibers: asbestosis, pleural inflammation, mesothelioma and other
lung cancers No acute symptoms; chronic effect can take up to 40 years to manifest Non-smoker: 5X increased risk of lung Cancer; Smoker: up to 100x risk
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Asbestos (continued) OSHA standard: 0.1 fiber/cm3 of air as an 8hr TWA for fibers longer
that 5 um and having a length to diameter ratio of at least 3:1 or excursion limit of 1 fiber/cm3 for 30 minutes
Medical Surveillance For all workers exposed to asbestos fibers at or above the TWA
or excursion limit Preplacement surveillance
Focus on respiratory system, cardiovascular, GI, PFT’s CXR Asbestos questionnaire Respirator standard
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Asbestos (continued)
Periodic surveillance Abbreviated OSHA asbestos questionnaire/CXR according to
schedule below
Yrs since first exposure
Age 15-35 yrs
Age 35+ to 45
Age 45+
0-10 Every 5 years Every 5 years Every 5 years
10+ Every 5 years Every 2 years Every 1 year
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Mineral Fibers: Asbestos and Ceramic Fibers/Man-Made Mineral Fibers (MMMF)
Ceramic Fibers One of a group of insulating materials known as MMMF Produced from aluminum oxide, silicon oxide and other metal
oxides PEL for respirable dust is 5mg/m3; Exposure limit of 1fiber/cc as
a TWA for ceramic fibers Surveillance
Medical/occupational histories with emphasis on the skin and respiratory tract
Physical exam Chemistries, blood count, PFT, CXR
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Hydrofluoric Acid Intermediate in production of fluorocarbons, aluminum fluoride,
cryolite; in production of uranium hexafluoride; metal cleaning, glass etching, polishing applications; occupational exposure can occur both by direct skin contact and by inhalation of fumes
Corrosive: causes calcium precipitation, stimulate nerve endings; binds body calcium causing life threatening systemic hypocalcemia after skin exposure or osteosclerotic bone changes after chronic exposure to HF ions; treat skin exposure with calcium gluconate
Workers with evidence of renal disease, impaired pulmonary function, scarring of the skin or cornea or osteosclerosis should be evaluated by a physician and if appropriate, informed of possibility of increased health risk from HF exposure.
Nonemergent exposures: UA, skin, cornea exams, hip xray (for males) should be offered Respiratory irritation: CXR, PFT Eye complaints: visual acuity/ophthalmological examination
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Hydrofluoric Acid Biological monitoring
ACGIH TLV – 3.0ppm 8-hr TWA and STEL 6ppm Preshift spot urinalysis
Collect at start of work shift at least 48 hrs after the last occupational exposure
Post shift urinalysis Evaluates accumulation of fluoride Collect at end of workshift after (4) consecutive days of exposure
If post shift urinary fluoride level exceeds 7.0mg/L, preshift spot urine samples for analysis should be collected within 2 weeks and a repeat post shift urinalysis If second sample is > the preshift limit of 4.0mg/L or post shift limit of
7.0mg/L, evaluated dietary sources, personal hygiene, basic work practices and environmental control
Job classification: evaluate all workers urinary fluoride levels on a group basis – if median post shift urinary fluoride levels >7.0mg/L, proceed with IH survey
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Cyanide Available as gas and technical liquid (3) most common cyanide salts: sodium, potassium, calcium Cyanide inhibits transfer of oxygen to cells OSHA PEL for cyanide salts is 4.7ppm; for potassium cyanide – 10ppm Acute exposure:
Lesser exposure: irritation of eyes, nose, throat, weakness, H/A, confusion, respiratory abnormalities, coma, convulsion
Minor symptoms after several minutes at breathing levels of 10-30ppm Death within an hour at level of 100ppm
Chronic exposure: Symptoms may persist for several months following cessation of exposure
Surveillance: Medical and occupational histories to evaluated any chronic effects: H/A,
nausea, dizziness; emphasis on skin, cardiovascular, pulmonary edema Periodic surveillance on basis of workers exposure potential to cyanides and
judgement of the physician Treatment: amyl nitrate by inhalation, followed by sodium nitrate
intravenously, then sodium thiosulfate IV
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Biological Monitoring Measurement of a chemical, its metabolite, or a nonadverse
biochemical effect in a biological specimen for the purpose of assessing exposure
Blood, urine, exhaled air Measures total exposure ( quantity of chemical absorbed regardless
of route of administration) vs workplace exposure (environmental monitoring)
Assesses the extent of exposure, therefore only an indirect measurement of risk of health effects as a result of exposure
Necessary conditions to consider biological monitoring Determinant must be present in blood, urine, exhaled air; suitable for
sampling; acceptable sampling method Method of analysis should be practical, produce valid reproducible
results over the range of concentrations Strategy of sample collection produces representative samples Results can be interpreted Action required for aberrant result established prior to monitoring
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Biological Monitoring
Methodology: Timing of Collection is critical
For chemicals with a short t1/2, the difference between sampling 15 minutes vs 1 hour after the end of exposure may alter the result by as much as a factor of 10.
Collection methods: proper containers, contamination with unwashed hands or clothing
Body site sampled Blood: most accurate
Volatile substances with short t1/2, have a variation in blood level Urine: easier to sample
24 hour urine most accurate Spot urine most practical; have to adjust for urine specific gravity or
Creatinine; Highly concentrated (SpG>1.030 or Cr>3g/L) or highly dilute (Spg<1.010 or CrM0.3-0.5g/L) usually not suitable for monitoring and a new specimen should be collected
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Biological Monitoring Methodology (continued)
Exhaled air Measurements of chemicals in exhaled air are with mid – exhaled or
end-exhaled Selecting a Lab
Only national certification in US if for blood lead California – only state with state certified labs for state mandated
cholinesterase testing for pesticide handlers WHO has conducted international quality assurance program for
blood lead and urine cadmium determinations Terminology
No Adverse Health Effect Level: level at which almost all workers will be free of symptoms, signs and adverse clinical lab test results Repro and Ca effects are not considered when calculating this level.
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Biological Monitoring
Terminology (continued) BEI (Biological exposure indices): level that corresponds to the level
measured in a worker exposed to a substance at the TLV-TWA; reference biological monitoring levels established by the ACGIH
Clinical Effect Level: level associated with signs, symptoms, abnormal lab tests
Timing of collection: most important for determination of the No Adverse Health Effect Level If t1/2 (rate of elimination of an agent) is short (min-hours), timing of critical; if
long (days to weeks) timing not critical Relative to standard work day and work week
PNS – Prior to next shift = 16 hrs after last shift EOS – End of shift = 15-30 minutes after the last exposure DS – during shift EWW – end of work week L2H – last 2 hrs of shift L4H – last 4 hrs of shift
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Who Needs the DOT Medical Card? Federal Motor Carrier Safety Regulations
(FMCSRs): Commercial Motor Vehicle
16 or more passengers including driver Transports hazardous materials Vehicle weight
10,001-26,000 lbs Medical card
26,001 or greater Medical card Drug and alcohol testing CDL license
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Automatic Disqualifications
Epilepsy Hearing loss not correctable by hearing aid Current diagnosis of alcoholism Vision deficit
Must have 20/40 both eyes, peripheral vision > 70 degrees
Methadone use
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Potential Disqualifications Monocular vision Hypertension Loss of limb Musculoskeletal disorder Heart condition Respiratory condition Psychiatric illness Controlled substance use
Narcotics, benzodiazepines
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Insulin Dependent Diabetes Update September 3, 2003
Type I diabetes no longer automatic disqualifier Significant documentation and specialist visits
required to complete application for exemption on part of driver
Must have annual exam by endocrinologist AND DOT recertification
Must comply with rules for diabetic control as set forth by FMCSA
http://a257.g.akamaitech.net/7/257/2422/14mar20010800/edocket.access. gpo.gov/2003/03-22409.htm
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New Guidelines for Cardiovascular Conditions
Oct. 2002 Conference on Cardiac Disorders and CMV drivers Shorter time for recertification post-MI Test of cardiac ejection fraction for many
conditions Implantable defibrillator disqualification
http://www.fmcsa.dot.gov/rulesregs/cardio.htm
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Blood Pressure Guidelines Part 391 Federal Register-Qualifications of
Drivers In effect as of 9/30/04 Diagnosis of hypertension on medication requires
more frequent certification BP should be measured on 3 separate occasions
while sitting to make determination of high BP If driver has no history of hypertension and has a
BP of 140/90, he can be certified for up to 2 years on initial examination.
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New Blood Pressure Guidelines for Drivers with Diagnosis of Hypertension Stage 1: 140/90-159/99
Certify one year Stage 2: 160/100-179/109
3-month certificate, treat, re-evaluate If BP at 3 months <140/90 recertify annually
Stage 3: 180/110 No certification until BP 140/90 Then recertify every 6 months
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Periodic Evaluation of Hypertensive Drivers Periodic screening and evaluation for “target
organ” damage Heart failure Stroke Retinopathy Kidney damage Coronary artery disease
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Heart Conditions: Ischemia
Focus: strength of the heart and risk of irregular heart beat (arrhythmia)
Risk factors: HTN, tobacco, Chol, LDL, DM, obesity, inactivity,
family history, >60yrs old, male, postmenopausal women
Truck drivers may have increased number of risk factors – sedentary job, irregular hours, dietary habits
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Heart Conditions: Myocardial Infarction (MI) New definition
Joint European Society/American College of Cardiology Committee in 2000
More people meet criteria for an MI due to increased accuracy in diagnoses Elevated troponin levels but no elevation of CPK-MB
2 month wait period after MI rather than 3 months ETT 4-6 weeks post MI, repeat every 2 years Ejection fraction must be > 40% No medication side effects
Recertification annually
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Heart Conditions: Angina
Annual recertification
ETT at least every 2 years
No angina at rest
Stable blood pressure
No medication side effects
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Heart Conditions: Percutaneous Coronary Interventions RTW 1-week post-procedure for stable
angina, unstable same as MI protocol ( 3 months)
ETT 3-6 months post-procedure and at least every 3 years
Stable blood pressure No medication side effects
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Coronary Artery Bypass Surgery 3 month waiting period
Must be stable on medication for at least 1 month
ETT annually
Resting EKG
Ejection fraction > 40%
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Heart Conditions: Arrhythmias Atrial fibrillation and Ventricular Tachycardia
Stable 1 month on medication Annual certification Blood thinners not necessarily disqualifying
WPW and Long QT syndrome: automatic disqualification
Pacemakers If underlying disease is not disqualifying certify
after 3 months Annual recertification
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Valvular Heart Disease
Cardiology evaluation EKG, chest x-ray, ETT, Echocardiogram
Types: Mitral stenosis, Mitral regurgitation Aortic stenosis, Aortic regurgitation
If no disqualifying factors (valve area and symptoms) than annual recertification
Repeat testing may be needed from every 6-12 months to every 5 years
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Vascular Disease
Abdominal aneurysms >5cm disqualifying 4-5cm disqualifying if symptomatic or pending
surgery <4cm – recertify annually if asymptomatic and no
surgery planned; annual Ultrasound to monitor size
3 month wait after surgery
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Peripheral Vascular Disease Generally not disqualifying unless resting
pain in lower extremities
3 month waiting period after vascular surgery
Annual recertification
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Deep Vein Thrombosis
Disqualifying unless adequately treated
On medication at least one month such as Coumadin with monthly blood testing
Annual recertification
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Heart Transplantation
Can consider certification after 1 year waiting period
Recertification every 6 months
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Respiratory Dysfunction Qualified to drive a commercial motor vehicle if
“…no medical history or clinical diagnosis of a respiratory dysfunction likely to interfere with ability to control and drive a CMV.” Sec.391.41(b)(5)
Impairment in respiratory function under emergency conditions (when greater oxygen supply is necessary for performance) may be detrimental to safe driving
If the medical examiner detects a respiratory dysfunction that in any way is likely to interfere with the drivers ability to drive, the driver must be referred to a specialist for evaluation and treatment
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Respiratory Dysfunction: Sleep Apnea Included in the advisory criteria as a respiratory condition that “may result in incapacitation”
Resulting daytime somnolence/decreased alertness is potential cause of MVA 2-4 fold increase in MVA in untreated sleep apnea
New medical exam form addresses sleep disorders
100,000 – 150,000 commercial drivers have sleep apnea
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Respiratory Dysfunction: Sleep Apnea Affects 2-3% of adult males
Obese, middle-aged males 3 key risk factor
BMI>28 Hypertension Neck size >17” ( increased neck circumference)
Other risk factors Alcohol History of snoring
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Respiratory Dysfunction: Sleep Apnea If any suspicion – refer for evaluation Medically unqualified until successfully treated
Surgery CPAP-waiting period of at least 30 days prior to
certification Weight loss
Annual Multiple Sleep-Latency Testing (Polysomnograph)
Follow-up in 1-2 months to assess effectiveness of treatment
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Other Worker Groups
The Biotech Industry Infectious agents, chemicals, carcinogens, radioisotopes, product
hazards, animal handling, reproductive hazards Healthcare workers
Latex allergy, anesthetic gases, chemical hazards, cytotoxic drugs, ergonomics, bloodborne pathogens
Municipal workers Sewage workers: biological hazards, bacteria, confined spaces,
chemicals, cancer risk Police and corrections: stress, ischemic heart disease, BBP, shift work,
chemical hazards, cancer risk Firefighters: chemical exposure, respiratory issues, physical
requirements, stress, biological exposure Bridge and Tunnel workers: Vehicular exhaust,/respiratory and cardiac
disease, ergonomics, temperature, noise, shift work, chemicals, microwave radiation
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References A Practical Approach to Occupational and Environmental
Medicine, 3rd Ed. McCunney RJ, Rountree PP, eds. Lippincott Williams and Wilkins, 2003
Current Occupational and Environmental Medicine, 3rd Ed. LaDou J, McGraw-Hill/Appleton & Lange, 2004
Fundamentals of Industrial Hygiene, 3rd Ed. Plog BA, Quinlan PJ, eds National Safety Council, 1988
Guide to the Medical Evaluation for Respirator Use. McLellan R, Schusler K, OEM Press, 2000
Instant Medical Surveillance, Mitchell FL, OEM Press, 2002
A DOT Medical Examination: A Guide to Commercial Drivers’ Medical Certification, 3rd Ed. Hartenbaum NP, OEM Press, 2003
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Be Safe!
Tony Soares, Safety Director
Compensation Solutions, Inc.
[email protected]: 1-888-201-5680 Ext. 192