Sept. 23, 2005 -- People who work with mineral oils, such as motor oil and hydraulic oil, may be more likely to develop rheumatoid arthritis.
A new study shows that men who had occupational exposure to mineral oils had a 30% higher risk of rheumatoid arthritis.
Researchers say rheumatoid arthritis is a disease that depends on several genetic as well as environmental factors, and these results suggest that occupational exposure to motor and hydraulic oils may increase the risk of rheumatoid arthritis in people with a family history of the disease.
The American College of Rheumatology specifies that in order to diagnose rheumatoid arthritis, four out of the following seven criteria must be present, observed by a doctor, and verified by patient history:
Mineral Oils Raise Arthritis Risks
In the study, which appears in Arthritis Research & Therapy, Swedish researchers looked at the link between exposure to mineral oils and the risk of developing rheumatoid arthritis in a group of about 1,400 people diagnosed with the disease and about 1,600 similarly matched healthy people who served as a comparison group.
All of the participants filled out a questionnaire with information regarding occupational exposure to a variety of mineral oils, including motor oil, hydraulic oil, cutting oil, form oil, and asphalt.
Only men reported high occupational exposure to mineral oils. In comparing the groups, researchers found men with high occupational exposure to motor or hydraulic oil, such as auto mechanics, had a 30% higher risk of developing rheumatoid arthritis than men not exposed to mineral oils.
Exposure to mineral oils was linked to those with rheumatoid-factor-positive rheumatoid arthritis. Occupational exposure to motor and hydraulic oil was also associated with a 60% increased risk of another type of the disease known as anticitrulline-positive rheumatoid arthritis.
Researchers say the results support previous studies that showed animals developed arthritic disease after exposure to mineral oils. The findings also raise questions about potential links between occupational exposure to other agents and an increased risk of rheumatoid arthritis.