Could workplace dust trigger RA?
According to a study published in the Annals of the Rheumatic Diseases, exposure to textile dust may be associated with an increased risk of developing rheumatoid arthritis. Additionally, occupational dust exposure is also linked to a risk of developing antibodies to rheumatoid arthritis, known as anti-citrullinated peptide antibodies (ACPA), thus potentially speeding up progression of the disease.
The researchers analyzed 910 Malaysian women who were diagnosed with early rheumatoid arthritis and 910 women of similar age without rheumatoid arthritis. Women were asked if they ever worked in the textile industry and what kind of chemicals and silica dust they were exposed to. Blood samples were also taken to check for rheumatoid arthritis antibodies, indicating the presence of the disease.
A total of 41 women with RA (4.5%) had been exposed to textile dust compared to 15 (1.7%) women who were disease-free. Those who were exposed to occupational textile dust were three times more likely to develop rheumatoid arthritis and the risk was double to test positive for ACPA. Nearly two-thirds of the women with RA (63%) had a positive ACPA test result and 40 percent carried the HLA-DRB1 SE genetic risk factor, which is known to increase the risk of developing RA. Those who carried the HLA-DRB1 SE genetic risk factor and who had been exposed to occupational textile dust were 39 times more likely to have a positive ACPA as compared to those who did not carry the genetic risk factor and who had not been exposed to textile dust.
This magnitude of risk is similar to that found for smoking among carriers of the same genetic risk factor. Researchers cautioned that the study was observational, so it cannot prove cause and effect. The study focused on women because few men work in the textile industry and smoking among men is common and smoking is a risk factor for developing rheumatoid arthritis. It is important to note that properties of textile dust will also differ, depending on the fabric and the chemicals used in production of various materials such as dyes, flame retardants and water repellants.
"The association between textile dust and risk of rheumatoid arthritis might involve several potential disease mechanisms since the differing physiochemical properties of airborne dust affect where it deposits in the respiratory tract," researchers wrote in the study.
Additionally, the shape of textile fibers allows them to penetrate into the lung, potentially resulting in inflammation. Bacteria in textile dust also can produce toxins that may cause respiratory disease. Researchers concluded, "From a public health perspective, our results imply that efforts should be considered to reduce the incidence of rheumatoid arthritis by reducing occupational exposure to textile dust."