Health Hazards of Solvents 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.
Dec 16, 2015
Health Hazards of Solvents
James E. Cone MD, MPH
and Karen Packard, RDH, MSThis presentation is made possible by a grant from the Association of Occupational and Environmental Clinics and the National Institute
for Occupational Safety & Health.
Module Goals
To provide an overview of occupational solvent exposure
To review potential health outcomes and public health prevention options.
To provide step by step approach to diagnostic testing and treatment of solvent-related diseases
To provide background information on specific solvents
To illustrate the diverse effects of solvents through cases involving solvent toxicity
What is a solvent?
Classes of Common Organic Solvents: aliphatic hydrocarbons amines cyclic hydrocarbons esters aromatic hydrocarbons alcohols halogenated hydrocarbons ketones aldehydes ethers
A solvent is a liquid at room temperature used to dissolve other substances
Permission to use photo requested from AIHA Lab Safety Committee
Scope of the Problem
Over 49 million tons of solvent chemicals are produced and used each year in the US alone.
Often exposure involves a mixture of solvents.
Permission requested from US Navy
Occupational Disease due to Solvents? 390,000 new cases of all types of
occupational disease appear annually in the US.
It is unknown how many of these cases may be related to solvent exposure.
Similar to other occupational diseases, 95% of all occupational solvent-related disease cases are never reported,
most are never recognized as being occupationally-related.
OccupationalEnvironmental Workplace solvents may also result in
exposures to neighborhood residents if discharged from workplaces without adequate controls.
Other hazards:– Fire or explosion– Improper storage or disposal
Used with Permission of
OccupationalEnvironmental Residual
perchloroethylene solvent may be present in freshly dry cleaned clothes
Properties of Solvents
Solubility
Non-flammability/ Flammability/ Explosivity
Volatility
Metabolism
Complex mixtures
Used with permission of Advanced Chemistry Development Co. Graphic
Routes of Solvent Exposure
Inhalation
Absorption
-skin
-mucous
membranes
Ingestion
InjectionJane Norling Graphic
Organ System Effects
Cor
el G
rap
hic
Biological Monitoring
For Example: Urine testing for:
– Benzene Phenol – Toluene Hippuric Acid, o-Cresol– Xylene Methyl Hippuric Acid– n-Hexane 2,5 hexanedione*
-References: • ACGIH Biological Exposure Indices* Not commercially available at this time
Corel Graphic
Occupations Exposed to Solvents Painters Construction workers Semiconductor workers Machinists / auto mechanics Manufacturing workers
– Glue, Paint, Chemical, Plastics– Rotogravure Printers, Metal Degreasers
Graffiti removers Refinery workers Manicurists Drycleaners Many others
Solvent Related Diseases Acute Intoxication Chemical Headache Chemical Hepatitis Chronic Toxic
Encephalopathy Hematological
Effects Renal Effects Reproductive Health
Effects Toxic Peripheral
Neuropathy
Bill Bowerman developed n-Hexane related peripheral neuropathy from glues used for running shoes
Dx of Solvent-Related Disease 10 Step Process
Certain conditions should trigger the thought that it might be solvent-related:
– Chemical hepatitis, peripheral neuropathy, chronic headache, chronic cognitive impairment, miscarriage, and asthma.
Corel Graphic
Dx: Step 1 - Medical & Exposure Records Prior medical records
Industrial Hygiene data
Labels, Material Safety Data Sheets (MSDS), Chemical Inventory Lists
OSHA reports
Dx: Step 2 - Exposure History Symptoms &
Exposure History Complete History &
Physical Examination
Specific job duties, solvent exposures
Exposure monitoring Frequency of acute
solvent intoxication episodes
Acute Solvent Intoxication -Stages
Narcosis impaired psychomotor
function as measured by reaction time, manual dexterity, coordination, or body balance
Anesthesia
Central nervous system depression
Respiratory arrest Unconsciousness
Dx: Step 3 - Medical History
Asthma
History of Blood Dyscrasias
Hearing loss
History of Psychological Problems– Prior to exposure– After exposure
Dx: Step 4 - Physical Examination
Focus on: Skin Eyes Gastro -
intestinal Neurologic
system Mental Status
Dx: Step 5 - Laboratory Tests
Screening Biological Indices Pathologic
Indices
NIOSH Database of Medical Tests for OSHARegulated Substances:http://www.cdc.gov/niosh/nmed/medstart.html
Corel Graphic
Dx: Step 6 - Other Testing Nerve Conduction
Studies
Color Vision
Hearing
Pontogram (blink reflex – facial and trigeminal nerve evaluation)
Peak flow
Dx: Step 7 - Site Visit“Walk Through” of Patient’s Workplace
Assess workplace and potential exposures
– Personal or area industrial hygiene sampling– Ventilation of worksite– Potential skin exposure
Obtain prior environmental test results, if available
Dx: Step 8 - Relationship?
Decide whether the the patient’s diagnosis is more likely than not work-related.
Is the latency period adequate?
Exposure data consistent?
Dx: Step 9 - Make the Diagnosis
Was the dose of the solvent exposure adequate, in your opinion, to cause the problem? (e.g., is there a history of acute intoxication episodes?)
OR Is patient particularly sensitive to the effects of solvents (e.g. increased individual susceptibility or acquired intolerance)?
Dx: Step 9 - Diagnosis
Rule out other diseases with similar outcomes:– e.g., Alcoholic Hepatitis/ Hepatitis B
Decide if a pre-existing condition exists that has been exacerbated.
File Clinician’s First Report, if required by State Law.
Dx: Step 10 - Disposition
Return to work
Modified duty / preclusions
Factors of disability– Objective/ Subjective
Vocational rehabilitation
Apportionment
Future medical care
Prevention of Solvent Exposures Elimination
Substitution
Engineering Controls
Administrative Controls – Isolation
Personal Protective Equipment
EducationUsed with permission from
Personal Protective Equipment Protective Clothing-Impermeable aprons
Gloves – Breakthrough time depends on type of glove, solvent exposure and activity.
Chemically resistant gloves: natural rubber, butyl rubber, chloroprene, nitrile, and fluorocarbon; or various plastics: polyvinyl chloride, polyvinyl alcohol, polyethylene
Permission requested from
Personal Protective Equipment-RespiratorsRespirator Program must include:
Training
Cleaning
Fit testing
Medical Clearance
Change of filters –schedule depends on exposure type and amount
Environmental pressures are often the primary cause of
solvent substitution.
Montreal ProtocolClean Air ActPollution Prevention (P2)
Additional Resources
Handouts Bibliography Web Sites
– Jonathan S Rutchik, MD, MPH Organic Solvents http://www.emedicine.com/neuro/topic285.htm
Acknowledgements: – Photos by Janet Delaney– Elizabeth Katz, MPH, CIH– Rosemarie Bowler, PhD– Public Health Institute, AOEC and NIOSH staff