Workplace exposure to petroleum-based lubricants is associated with 38% higher odds of multiple sclerosis, according to a study published on November 4, 2026, in the medical journal Neurology, Multiple Sclerosis News Today reported.
The study, conducted in Sweden and led by Anna Karin Hedström of the Karolinska Institutet, analyzed data from 2,872 people diagnosed with multiple sclerosis between 2005 and 2015 alongside 6,122 matched control participants without the disease.
Researchers found that occupational contact with engine oil, concrete form oil, and cutting fluids increased disease odds, with risk climbing alongside longer duration and weekly hours of exposure. This epidemiological association was particularly pronounced among current smokers and individuals carrying specific genetic variants linked to immune system function.
“Our findings suggest that exposure to these products in the workplace, which is common in industrial settings, is associated with higher odds of MS, especially when combined with smoking or certain genetic characteristics,” said Anna Karin Hedström, MD, PhD, the study's first author and a senior research specialist at Karolinska Institutet.
Multiple Sclerosis Causes Neuroinflammation Through Myelin Damage
Multiple sclerosis is a chronic, immune-mediated central nervous system disorder wherein autoreactive lymphocytes mistakenly breach the blood-brain barrier to target myelin, the protective sheath insulating axonal fibers in the brain and spinal cord. This localized demyelination produces neuroinflammation, axonal transection, and progressive neurological impairment.
Previous public health investigations have linked lung irritants such as ambient air pollution, organic solvents, and cigarette smoke to elevated multiple sclerosis risk, but occupational petroleum-derived lubricants had not been comprehensively evaluated until now, as noted by Anna Karin Hedström in a press release from the American Academy of Neurology.
“Previous research has linked lung irritants such as cigarette smoke, organic solvents and air pollution to MS risk, but petroleum-derived lubricants have not been closely studied,” Hedström said.
The study cohort comprised participants with an average age of 35 living across Sweden, where researchers gathered detailed occupational histories through standardized questionnaires. Among the total study population, 251 individuals with multiple sclerosis (8.7%) reported workplace exposure to petroleum-derived lubricants, compared to 399 participants without the disease (6.5%), according to Newswise.
Among those exposed, 23% worked in metalworking, 17% in construction, 11% in automotive repair, and 10% in machinery maintenance. Men reported occupational exposure at higher rates than women, though the statistical association between lubricant contact and multiple sclerosis odds held true across both sexes after adjusting for confounding variables including age, sex, residential area, and smoking habits.
Petroleum Mists Show Dose-Dependent Disease Associations
Granular breakdown of the exposure metrics revealed a dose-dependent relationship between occupational inhalation or dermal absorption of petroleum mists and the statistical odds of developing the disease. When researchers evaluated specific chemical formulations separately, engine oil, concrete form oil, and cutting fluids all showed significant positive associations with the disease, whereas hydraulic oil did not demonstrate a statistically significant link.
To address reverse causality—the possibility that subclinical disease already altered occupational behavior before formal diagnosis—investigators performed a temporal sensitivity analysis by excluding exposures occurring within the seven years immediately preceding symptom onset.
In this restricted subset, individuals exposed to petroleum-derived lubricants at least seven years prior to symptom manifestation retained a 55% higher odds of multiple sclerosis compared to unexposed peers. These findings show a persistent temporal association that survives latency adjustments, though the authors emphasized that the observational design demonstrates correlation rather than definitive causation.
Gene-Environment Synergy and Smoking Interactions
The investigation further explored how lifestyle and genetic architecture modulate environmental neurotoxic risks. Researchers analyzed blood samples to evaluate human leukocyte antigen (HLA) gene variants known to influence autoimmune susceptibility.
The association between occupational lubricant exposure and multiple sclerosis was noticeably stronger among current smokers and individuals lacking the protective genetic variant HLA-A*02:01. Conversely, the association trended stronger among participants carrying the risk allele HLA-DRB1*15:01, a well-established genetic marker for multiple sclerosis vulnerability.
When these risk factors converged, the statistical odds compounded dramatically. Current smokers who were occupationally exposed to petroleum-based lubricants, carried the high-risk HLA-DRB1*15:01 variant, and lacked the protective HLA-A*02:01 variant exhibited nearly 34 times the odds of multiple sclerosis compared to nonsmokers possessing neither workplace exposure nor the evaluated genetic risk alleles.
However, the study authors cautioned that this specific stratified calculation derived from a very small sample size of just 16 multiple sclerosis patients and two control participants, rendering this specific risk estimate less precise and warranting validation in larger international cohorts.
Petroleum Lubricant Mists Increase Multiple Sclerosis Risk
- Occupational Risk: Workers in metalworking, construction, and machinery maintenance who regularly inhale petroleum-derived lubricant mists show a 38% higher statistical association with multiple sclerosis.
- Cumulative Exposure: Both the number of years spent working with these fluids and the weekly hours of contact increase the statistical odds of developing the condition.
| Exposure Metric & Variable | Study Cohort Data (MS vs. Control) | Statistical Association / Odds Ratio |
|---|---|---|
| Workplace Petroleum Lubricants | 8.7% (MS) vs. 6.5% (Control) | 38% higher odds overall |
| Cumulative Duration & Intensity | Per year / Per weekly hour | +2% per year, +2% per weekly hour |
References
- Hedström, A.K., et al. (2026). Occupational Exposure to Petroleum-Derived Lubricants and Risk of Multiple Sclerosis. Neurology. American Academy of Neurology.
- National Institute of Environmental Health Sciences (NIEHS). Autoimmune Diseases and Environmental Exposures.
- Centers for Disease Control and Prevention (CDC). Multiple Sclerosis Surveillance and Epidemiology.
- World Health Organization (WHO). Occupational Health and Safety in Industrial Settings.
