Also known as: Chemical Hepatitis
Hospital: Report by phone, fax, or mail
Lab: Report by phone, fax, or mail
Physician/Health care providers: Report by phone, fax, or mail
Medical Examiners: Report by phone, fax, or mail
Poison Control Centers: Report by phone, fax, or mail
Occupational Nurses: Report by phone, fax, or mail
Local Public Health Agency (LPHA): No follow-up required, unless outbreak occurrence
Report to the Iowa Department of Public Health:
Iowa Department of Public Health
Bureau of Environmental Health Services
Lucas State Office Building
321 E. 12th Street
Des Moines, Iowa 50319-0075
Phone (Mon-Fri 8 am - 4:30 pm): 800-972-2026
24-hour Disease Reporting Hotline: (For use outside of EH office hours) 800-362-2736
The liver processes everything a person consumes. Among many complex functions, the liver cleanses the blood, regulates the supply of body fuel, and manufactures many essential body proteins, including clotting factors. The liver is susceptible to injury by chemicals because it plays a fundamental role in chemical metabolism. It has the unique job of processing almost all chemicals and drugs that enter the blood stream and removing the chemicals that are difficult to excrete. The liver turns these chemicals into products that can be eliminated from the body through bile or urine. However, during this chemical process, unstable, highly toxic products, which can attack and injure the liver, are sometimes produced.
A. Clinical Description
Toxic hepatitis is any acute or sub-acute necrosis of the liver or other unspecified chemical hepatitis caused by exposure to non-medicinal toxic agents other than ethyl alcohol, including, but not limited to, carbon tetrachloride, chloroform, tetrachloroethane, trichloroethylene, phosphorus, TNT, chloronapthalenes, methylenedianilines, ethylene dibromide, and organic solvents. This includes ICD-9 codes 572.2 and 573.3 or ICD-10 codes K71.0 to K71.9.
Clinically, toxic hepatitis can resemble any form of acute or chronic liver disease, such as viral hepatitis or bile-duct obstruction. Symptoms such as nausea, vomiting, fever, jaundice, enlarged liver and right upper quadrant abdominal tenderness are often identical to viral hepatitis. Elevated liver enzymes, other liver blood tests, and liver biopsy findings may also be identical to viral hepatities. Liver function tests are often used in occupational medicine surveillance programs for people who are exposed to toxic chemicals in the workplace. In chronic exposure cases, the first signs or symptoms may be a progressive elevation of liver function tests.
B. Sources of Exposure
In an occupational setting, toxic hepatitis can occur when workers are exposed to industrial chemicals capable of causing liver damage. Chemical spills, improper ventilation, confined spaces, or the lack of adequate skin and respiratory protective measures may increase the risk of exposure above safe limits. Underlying health problems, age, the use of alcohol, and some types of pain relievers, prescription medications, herbal supplements or other over-the-counter products can also increase a worker’s risk of developing liver damage when exposed to industrial chemicals.
There are lists of chemicals known to cause illness or death due to acute hepatic injury after occupational exposure. Workers who improperly handle these chemicals could suffer liver damage as the principal toxic effect of the substance. Refer to The National Library of Medicine Haz-Map website for disease information, a list of chemicals, and a searchable database. The NIOSH Pocket Guide to Chemical Hazards is another reference useful to determining exposure risks and preventive measures. Reference links are listed at the end of this document.
C. Population at Risk
Most statistics on toxic hepatitis combine the numbers for toxic hepatitis caused by drugs and toxic hepatitis caused by exposure to chemicals. One source lists the incidence as 8 out of 10,000 people. Another source says toxic hepatitis is implicated in the United States in 2 to 5 percent of hospitalizations for jaundice, an estimated 15 to 30 percent of fulminant liver failure cases, and approximately 40 percent of acute hepatitis cases in people over 50 years.
The National Library of Medicine Haz-Map website lists 23 primary hepatotoxins and over 600 secondary hepatotoxins, increasing the risk of disease for workers in occupations or industries using these chemicals. Hazardous response workers, first responders, and people who work in confined spaces are other high risk groups for possible exposure.
D. Diagnosis, Treatment, and Prognosis
Diagnosis of toxic hepatitis caused by chemical exposure requires a thorough assessment of the patient, including clinical signs and symptoms, laboratory testing, an exposure history, and possible liver imaging and biopsy. Some of these tests are used to rule out other types of hepatitis. The medical provider must pay close attention to the environmental and occupational exposures to chemicals of each patient as well as all drugs used (prescribed or over the counter ones, including herbal remedies). Some forms of chemical liver injury will occur within hours, days, or weeks of exposure; however, sometimes it takes months of regular exposure to a chemical or ingestion of a drug before liver injury becomes apparent. Workers known to have regular exposure to potentially damaging chemicals should be routinely screened.
If a person is suspected of having, or has been diagnosed with toxic hepatitis, exposure to the chemical or drug(s) identified as the possible causative agent should be immediately discontinued. Rest is indicated if symptoms are severe. If nausea and vomiting are significant, hospitalization and intravenous fluids may be advised. People with acute hepatitis should avoid physical exertion, alcohol, and any hepatotoxic substances. Consultation with a medical toxicologist should be considered.
Liver inflammation usually subsides within days or weeks after exposure to the chemical or drug is stopped. In severe cases, liver failure can occur. The overall mortality rate for drug-induced liver injury is around 5 percent.
E. Prevention of Exposure
People who work with or use hazardous chemicals should be trained regarding the risks, and should take all necessary precautions to protect themselves from exposure. Safety Data Sheets (SDS – formerly called Material Safety Data Sheets or MSDS) can provide information about personal protective equipment (PPE) requirements, first aid, and exposure risks. If workers do come in contact with a harmful substance, they should follow the guidelines established in their workplace, and call the local emergency services or poison control center for help as needed.
The National Institute of Occupational Safety and Health (NIOSH) Pocket Guide to Chemical Hazards (http://www.cdc.gov/niosh/npg/default.html) is intended as a source of general industrial hygiene information on several hundred chemicals/classes for workers, employers, and occupational health professionals. The NPG does not contain an analysis of all pertinent data; rather it presents key information and data in abbreviated or tabular form for chemicals or substance groupings (e.g. cyanides, fluorides, manganese compounds) that are found in the work environment. The information found in the NPG should help users recognize and control occupational chemical hazards.
- Chemical names, synonyms, trade names, CAS, RTECS, and DOT ID and Guide numbers
- Chemical structure/formula, conversion factors
- NIOSH Recommended Exposure Limits (RELs)
- Occupational Safety and Health Administration (OSHA) Permissible Exposure Limits (PELs)
- NIOSH Immediately Dangerous to Life and Health values (IDLHs)
- Physical description and chemical and physical properties of agents
- Measurement methods
- Personal protection and sanitation recommendations
- Respirator selection recommendations
- Incompatibilities and reactivities of agents
- Exposure routes, symptoms, target organs, and first aid information