Health Hazards of Solvents Case Studies

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					Health Hazards of Solvents
       Case Studies

     James E. Cone MD, MPH
   and Karen Packard, RDH, MS
This presentation is made possible by a grant from the
Association of Occupational and Environmental Clinics
 and the National Institute for Occupational Safety &
   Elizabeth Katz, MPH, Industrial Hygienist,
    Occupational Health Branch, California
    Department of Health Services
   Robert Harrison, MD, MPH, UCSF
    Occupational Medicine Clinic
   Karen Packard, Health Educator
   Janet Delaney, Photographer
   Specific photo acknowledgements are listed
    on slides
Case 1: Auto Mechanic
                                                                 24 y.o. male
                                                                 Auto Mechanic
                                                                 Worked for 22 months
                                                                 October 1996: fatigue
                                                                 January 1997 :
                                                                  – Swollen hands
                                                                  – Numbness, tingling both
                                                                    hands and plantar
                                                                    surfaces of both feet
                                                                  – Spread to legs, waist
                                                                    and lower forearms

                                                                 Other workers reported
                                                                  similar symptoms, less
Photo used with permission: A. Chandrasekhar, Loyola University
Medical History
  No prior history of diabetes or
 thyroid disease
 Alcohol:   One drink per week.

Exposure History
    Auto Mechanic: Brake repair

    Top worker for 10 months
     (# jobs/day)
    Exposure History: Amount
   Used 5-10 12-oz. aerosol cans / day of same
    brake cleaner
   Frequently sprayed on rag, latex gloves used
   No local ventilation but had open garage
    doors, except in winter
   No IH or biological monitoring in past
   No hobbies with solvent exposure
   Previous use of perchloroethylene mixtures
Specific Solvent
                  50-60% hexane
                   (composed of 20-80%

                  20-30% toluene

                  1-10% each of methyl
                   ethyl ketone, acetone,
                   isopropanol, methanol
                   & mixed xylenes.
MSDS for Brake Cleaner
Physical Exam
                                   No skin changes

                                   HEENT:
                                     –   No nystagmus
                                     –   Visual acuity normal
                                     –   No loss of smell
                                     –   No loss of hearing

                                   GI: Liver size 8mm
                                    to percussion

     Photo used with permission: A. Chandrasekhar, Loyola University
Neurological Exam

   Marked sensory deficits with complete loss of
    joint position sense in lower extremities
   Romberg test – positive
   Abnormal tandem gait
   Deep tendon reflexes absent bilaterally in all
                          Photo used with permission: A. Chandrasekhar, Loyola University
Mental Status

   Normal serial 7’s

   Recalls 3 objects at 5 minutes

   Digit span 10 forward, 6 reverse
                              Photo used with permission
                              A. Chandrasekhar, Loyola University
Diagnostic Tests, Rx, Referral
   Liver Function: AST 33 U/L (Normal 0-35
    U/L), ALT 50 (Normal 0-35 U/L).
   No biological monitoring was performed as he
    had been removed from further exposure.
    – What biological monitoring could have been
      performed if he was continuing to work with
    – Nerve Conduction Tests
    – Abnormal, subacute progressive mixed motor -
      sensory neuropathy with predominant distal nerve
   Initial Diagnosis: Guillain-Barre Syndrome
   Treatment: Trial of steroids
   Referral: Occupational Medicine Consultation
Biological Monitoring
Substance   TLV   Skin Abs. BEI Urine/l
Hexane      50    Yes       2,5hexanedione
                            5 mg/g creat.
Toluene     50    Yes       O-cresol 0.5 ug
MEK         200             MEK 2 mg
Acetone     500             Acetone 50 mg
Methanol    200   Yes       Methanol 15 mg
Xylene      100             Methylhippuric
                            Acid 1.5 g/g Cr.
Isopropanol 200   Yes
Site Visit

   Large open bays
   Multiple solvents present
   Storage locker of old solvent products
   Confirmed that other workers report
    similar symptoms, less severe
   Management concerned, willing to stop
    use of n-hexane containing products
Diagnosis and Course
   Toxic Peripheral Neuropathy due to n-
    hexane solvent exposure, likely potentiated
    by exposure to multiple other solvents
   Course:
    –   Removed from further exposure
    –   Off work for 2 1/2 years
    –   Gradual return of function
    –   Residual numbness of lower extremities 3 years
   Reference: n-Hexane--Related Peripheral Neuropathy
    Among Automotive Technicians --California, 1999—2000