Toxins Promoting Autoimmunity That Make Infections Worse
And Hinders Cure From the Three Bs
25-Exposure Autoimmune Master Table
I have ranked the agents by the overall strength of human epidemiology, clinical evidence, and mechanistic plausibility—not simply by their general toxicity.
Evidence Scale
★★★★★ = Strongest human evidence
★★★★ = Substantial
★★★ = Moderate/emerging
★★ = Limited but biologically plausible
| # | Exposure/Toxicant | Common Sources | Autoimmune Diseases/Phenotypes Most Associated | Important Immune Mechanisms | Potential Clinical/Exposure Tests* | Persistence | Evidence |
|---|---|---|---|---|---|---|---|
| 1 | Crystalline Silica | Mining, stone cutting, engineered-stone fabrication, construction, sandblasting | Systemic sclerosis, RA, SLE, ANCA vasculitis | Inflammasome activation, macrophage injury, autoantigen release, oxidative stress | Occupational history; chest imaging/PFTs for silica disease; disease-specific autoantibodies | Lung-retained | ★★★★★ |
| 2 | Cigarette/Tobacco Smoke | Active/passive smoking | ACPA+ RA, Graves disease, MS, SLE associations | Protein citrullination, oxidative stress, NETosis, mucosal autoimmunity | Cotinine for recent exposure; RF/anti-CCP according to clinical indication | Repeated exposure | ★★★★★ |
| 3 | Trichloroethylene (TCE) | Metal degreasing, solvents, groundwater contamination | Systemic sclerosis, autoimmune hepatitis-like disease, lupus-like autoimmunity | CD4 activation, oxidative protein modification, IFN-γ↑, loss of tolerance | Blood/urine metabolites mainly for recent occupational exposure; groundwater/environmental testing | Days biologically; groundwater may persist years | ★★★★½ |
| 4 | Organic-Solvent Mixtures | Paints, degreasers, printing, manufacturing | Systemic sclerosis, systemic autoimmune diseases | Oxidative stress, protein adducts, epigenetic alteration | Detailed occupational history; targeted solvent metabolites where appropriate | Variable | ★★★★ |
| 5 | Mercury | Seafood, occupational sources, some contaminated environments | ANA positivity; autoimmune-like phenomena; thyroid/renal immune effects reported | Polyclonal B-cell activation, autoantibody formation, oxidative stress | Blood mercury; urine mercury depending exposure species | Weeks–months; tissue dependent | ★★★★ |
| 6 | PM2.5/Air Pollution | Traffic, combustion, industry, wildfire smoke | RA, connective-tissue disease, psoriasis, IBD; SLE signals | Oxidative stress, lung inflammation, NETosis, cytokine activation | Ambient exposure assessment; no diagnostic blood “PM2.5 test” | Continuous exposure | ★★★★ |
| 7 | Agricultural Pesticides | Farming, spraying, occupational drift | RA, SLE, Sjögren syndrome associations | Oxidative stress, immunomodulation, endocrine effects | Exposure history; specific metabolites only for selected pesticides/recent exposure | Variable | ★★★★ |
| 8 | PFOA | Legacy PFAS, contaminated water, industrial sources | Immune dysregulation; IBD/celiac associations; thyroid/RA signals being studied | Altered antibody responses, PPAR signaling, cytokine changes | Serum PFAS | Years | ★★★½ |
| 9 | PFOS | Firefighting foam, legacy stain-resistant products, water contamination | Immune dysregulation; possible autoimmune thyroid/GI associations | Altered B/T-cell responses, impaired vaccine antibody response | Serum PFAS | Years | ★★★½ |
| 10 | PFHxS / PFNA and Other Long-Chain PFAS | AFFF, industrial contamination, consumer legacy sources | Autoimmune/immune-mediated disease evidence emerging | Immunotoxicity, endocrine-immune interaction | Serum PFAS | Years | ★★★ |
| 11 | Tetrachloroethylene (PCE) | Dry cleaning, metal cleaning, contaminated water | Systemic sclerosis and systemic autoimmune associations | Oxidative stress, solvent-mediated protein modification | Blood/breath/urine in recent exposure; environmental sampling | Days biologically; environmental persistence | ★★★½ |
| 12 | PCBs | Legacy transformers, contaminated fish, old building materials | Autoimmune thyroid disease; immune dysregulation; possible RA/MS associations | AhR signaling, endocrine disruption, B/T-cell effects | Serum PCB congeners | Years–decades | ★★★ |
| 13 | Dioxins/TCDD | Combustion, industrial contamination, food-chain accumulation | Autoimmune immune dysregulation; thyroid/inflammatory associations | AhR, Treg/Th17 alteration, B-cell suppression/alteration | Serum dioxins mainly specialized testing | Years | ★★★ |
| 14 | Organochlorine Pesticides | Historical DDT/chlordane/lindane; contaminated food/environment | RA/SLE/thyroid-autoimmune signals | Endocrine disruption, oxidative stress, cytokine effects | Serum persistent-organic-pollutant testing mainly research/specialized | Years | ★★★ |
| 15 | Organophosphate Pesticides | Agriculture, historical residential insecticides | RA/systemic autoimmune associations | Cholinergic effects plus oxidative and cytokine dysregulation | RBC/plasma cholinesterase for substantial recent exposure; urinary metabolites | Usually short | ★★★ |
| 16 | Cadmium | Cigarette smoke, food, batteries, industry | RA/autoantibody associations; immune dysregulation | Oxidative stress, inflammasome activation, altered lymphocytes | Blood/urine cadmium | 10–30-year body half-life | ★★½ |
| 17 | Arsenic | Groundwater, occupational exposure, some foods | Autoimmune/inflammatory dysregulation; less consistent disease-specific evidence | Oxidative stress, epigenetic changes, altered T-cell function | Urine arsenic with speciation | Days biologically; chronic exposure common in affected water sources | ★★½ |
| 18 | Lead | Old paint/dust, plumbing, firing ranges, occupations | Autoantibody/immune alterations; direct autoimmune disease evidence weaker | Oxidative stress, altered T-cell/cytokine function | Blood lead | Bone stores: years–decades | ★★ |
| 19 | BPA | Food-contact materials, epoxy resins, receipts | Thyroid and systemic-autoimmune associations being investigated | Estrogen-receptor effects, B-cell/Th17/Treg modulation | Urinary BPA mainly exposure/research use | Hours | ★★½ |
| 20 | Phthalates/DEHP | PVC, food packaging, medical devices, consumer products | Thyroid/immune-autoimmune signals; evidence emerging | Endocrine-immune signaling, oxidative stress | Urinary metabolites | Hours–days | ★★½ |
| 21 | PBDE Flame Retardants | Older furniture foam, electronics, household dust | Autoimmune thyroid and immune-dysregulation signals | Thyroid disruption, inflammatory signaling | Serum PBDEs mainly specialized/research | Years | ★★ |
| 22 | PAHs / Benzo[a]pyrene | Tobacco smoke, traffic exhaust, wildfire smoke, combustion | RA/SLE inflammatory-autoimmune pathways | AhR activation, oxidative DNA damage, epigenetic effects | Urinary PAH metabolites such as 1-hydroxypyrene in exposure assessment | Hours–days | ★★ |
| 23 | DDT/DDE | Legacy pesticide residues and food-chain exposure | Thyroid/systemic autoimmune associations under study | Endocrine disruption, cytokine alteration | Serum DDE/DDT | Years | ★★ |
| 24 | Formaldehyde | Building materials, laboratories, furniture, combustion | Strong sensitization/immune activation; systemic autoimmunity evidence limited | Protein adduct formation, mucosal inflammation, hypersensitivity | Exposure monitoring; no useful routine autoimmune “formaldehyde test” | Short biological half-life | ★½–★★ |
| 25 | Styrene | Fiberglass, plastics, resins, manufacturing | Immune alterations; weak direct autoimmune epidemiology | Oxidative stress, inflammatory signaling | Urinary mandelic/phenylglyoxylic acids for occupational exposure | Short | ★½–★★ |
*Exposure testing does not establish that the chemical caused an autoimmune disease. Tests should be interpreted against exposure timing, toxicokinetics, specimen choice and validated reference ranges.
Crystalline Silica — Strongest Occupational Example
A nationwide Danish cohort of more than 3 million workers found exposure-response relationships between respirable crystalline silica and autoimmune rheumatic disease. In highly exposed men, the incidence rate ratio was 1.53 for the combined autoimmune outcomes, 1.62 for systemic sclerosis, and 1.57 for rheumatoid arthritis.
Full reference: Boudigaard SH, Schlünssen V, Vestergaard JM, et al. Occupational exposure to respirable crystalline silica and risk of autoimmune rheumatic diseases: a nationwide cohort study. International Journal of Epidemiology. 2021;50(4):1213-1226. doi:10.1093/ije/dyaa287.
Cigarette Smoke
Smoking has particularly strong evidence for seropositive/ACPA-positive rheumatoid arthritis. A dose-response meta-analysis found an approximately twofold RA risk at 21–30 pack-years compared with never smokers, with an even stronger association for RF-positive disease.
Full reference: Di Giuseppe D, Discacciati A, Orsini N, Wolk A. Cigarette smoking and risk of rheumatoid arthritis: a dose-response meta-analysis. Arthritis Research & Therapy. 2014;16. doi:10.1186/ar4498.
Additional reference: Zhang X, Zhang X, Yang Y, et al. Association between passive smoking and the risk of rheumatoid arthritis: a systematic review and meta-analysis. Clinical Rheumatology. 2023;42(3):663-672. doi:10.1007/s10067-022-06433-3.
Trichloroethylene
TCE has one of the most interesting chemical-autoimmunity evidence bases because there is concordance between experimental models and human occupational evidence. A major review reported a pooled occupational association with scleroderma in men and autoimmune effects in experimental lupus models.
Full reference: Cooper GS, Makris SL, Nietert PJ, Jinot J. Evidence of autoimmune-related effects of trichloroethylene exposure from studies in mice and humans. Environmental Health Perspectives. 2009;117(5):696-702. doi:10.1289/ehp.11782.
A 2025 review also describes TCE-associated occupational hypersensitivity syndrome involving anti-CYP2E1 autoantibodies and CD4+ T-cell/cytokine abnormalities.
Organic Solvents
The broader solvent literature suggests an association between occupational organic-solvent exposure and systemic autoimmune disease, although risk varies substantially among individual solvents.
Full reference: Barragán-Martínez C, Speck-Hernández CA, Montoya-Ortiz G, et al. Organic solvents as risk factor for autoimmune diseases: a systematic review and meta-analysis. PLoS ONE. 2012;7(12). doi:10.1371/journal.pone.0051506.
Mercury
Mercury is notable because epidemiologic work has linked exposure to antinuclear antibody positivity, while animal research demonstrates mercury-induced autoimmunity. Importantly, ANA positivity is not equivalent to clinical lupus.
Full reference: Somers EC, Ganser MA, Warren JS, et al. Mercury exposure and antinuclear antibodies among females of reproductive age in the United States: NHANES. Environmental Health Perspectives. 2015;123(8):792-798. doi:10.1289/ehp.1408751.
Full reference: Pollard KM, Cauvi DM, Toomey CB, Morris KV, Kono DH. Mercury-induced inflammation and autoimmunity. Biochimica et Biophysica Acta General Subjects. 2019;1863(12):129299. doi:10.1016/j.bbagen.2019.02.001.
Air Pollution / PM2.5
Large population studies increasingly connect chronic air-pollution exposure with immune-mediated diseases. Potential mechanisms include oxidative stress, pulmonary immune activation, NET formation and systemic cytokine signaling.
Full reference: Adami G, Pontalti M, Cattani G, et al. Association between long-term exposure to air pollution and immune-mediated diseases: a population-based cohort study. RMD Open. 2022;8.
Pesticides
Agricultural exposures are repeatedly implicated in epidemiologic studies of autoimmune disease, especially RA and SLE, but individual pesticides should not be treated as having identical risks.
Full reference: Parks CG, Walitt BT, Pettinger M, et al. Insecticide use and risk of rheumatoid arthritis and systemic lupus erythematosus in the Women’s Health Initiative Observational Study. Arthritis Care & Research. 2011;63(2):184-194.
PFAS
PFAS deserve substantial attention because human immunotoxicity is well supported, although evidence for particular autoimmune diagnoses is less definitive than for silica→systemic sclerosis/RA or smoking→RA. Their persistence makes exposure history particularly relevant.
Chlorinated Solvents and Persistent Organic Pollutants
PCE, PCBs, dioxins and organochlorine pesticides can alter immune signaling, endocrine function, AhR pathways, Treg/Th17 balance and inflammatory responses. However, immune perturbation should not automatically be labeled autoimmune disease.
Metals, Endocrine Disruptors and Combustion Chemicals
For cadmium, arsenic, lead, BPA, phthalates, PBDEs, PAHs, DDE, formaldehyde and styrene, mechanistic evidence is often considerably stronger than disease-specific human epidemiology. These deserve investigation when exposure history is convincing, but they should sit below silica, smoking, and selected solvents in an evidence-based clinical ranking.
Most Important Autoimmune Laboratory Markers to Pair With Clinical Suspicion
When symptoms and examination point toward autoimmune disease, conventional testing can include ANA with titer/pattern; ENA panel (SSA/Ro, SSB/La, Sm, RNP); anti-dsDNA; C3/C4; RF; anti-CCP; ANCA with PR3/MPO; thyroid peroxidase and thyroglobulin antibodies; ESR/CRP; CBC; CMP; urinalysis and urine protein/creatinine ratio. Disease-specific testing should be driven by the phenotype rather than ordering every antibody indiscriminately.
Core References Covering the Whole Field
Parks CG, Conrad K, Cooper GS. Occupational exposure to crystalline silica and autoimmune disease. Environmental Health Perspectives. 1999;107(Suppl 5):793-802.
Cooper GS, Makris SL, Nietert PJ, Jinot J. Evidence of autoimmune-related effects of trichloroethylene exposure from studies in mice and humans. Environmental Health Perspectives. 2009;117(5):696-702. doi:10.1289/ehp.11782.
Barragán-Martínez C, Speck-Hernández CA, Montoya-Ortiz G, et al. Organic solvents as risk factor for autoimmune diseases: a systematic review and meta-analysis. PLoS ONE. 2012;7(12). doi:10.1371/journal.pone.0051506.
Khan MF, Wang H. Environmental exposures and autoimmune diseases: contribution of gut microbiome. Frontiers in Immunology. 2020;10:3094. doi:10.3389/fimmu.2019.03094.
Boudigaard SH, Schlünssen V, Vestergaard JM, et al. Occupational exposure to respirable crystalline silica and risk of autoimmune rheumatic diseases: a nationwide cohort study. International Journal of Epidemiology. 2021;50(4):1213-1226.