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 &
Health.
Acknowledgements





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

Photo used with permission: A. Chandrasekhar, Loyola University
Other workers reported
similar symptoms, less
severe
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%
n-hexane)

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
extremities
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
solvents?
– Nerve Conduction Tests
– Abnormal, subacute progressive mixed motor sensory neuropathy with predominant distal nerve
involvement



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
Xylene
100
Isopropanol 200
Yes
Methanol 15 mg
Methylhippuric
Acid 1.5 g/g Cr.
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 nhexane 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
later
Reference: n-Hexane--Related Peripheral Neuropathy
Among Automotive Technicians --California, 1999—2000
http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5045a3.htm