Transcript Health Hazard Solvents - AOEC
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.
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?
A solvent is a liquid at room temperature used to dissolve other substances
Classes of Common Organic Solvents:
aliphatic hydrocarbons amines cyclic hydrocarbons aromatic hydrocarbons halogenated hydrocarbons aldehydes esters alcohols ketones ethers 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.
Occupational Environmental 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
Occupational Environmental 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 Injection Jane Norling Graphic
Organ System Effects
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 OSHA Regulated 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 Education Used 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 Respirators Respirator Program must include: Training Cleaning Fit testing Medical Clearance Change of filters amount –schedule depends on exposure type and
Environmental pressures are often the primary cause of solvent substitution .
Montreal Protocol Clean Air Act Pollution 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