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