A study of inflammatory biomarkers in crystalline silica exposed rock drillers

Int Arch Occup Environ Health. 2024 Jul;97(5):587-595. doi: 10.1007/s00420-024-02070-2. Epub 2024 May 4.

Abstract

Background: Crystalline silica (CS) exposure can cause serious lung disease in humans, but mechanisms of pulmonary toxicity have not been completely elucidated.

Aims: To assess pro-inflammatory and anti-inflammatory biomarkers and biomarkers related to the development of chronic obstructive pulmonary disease and fibrosis in serum of rock drillers exposed to CS.

Methods: Rock drillers (N = 123) exposed to CS and non-specified particulate matter (PM) were compared to 48 referents without current or past exposure to PM in a cross-sectional study.

Results: The rock drillers had been exposed to CS for 10.7 years on average. Geometric mean (GM) current exposure was estimated to 36 µg/m3. Their GM concentration of matrix metalloproteinase 12 (MMP-12) was significantly higher (16 vs. 13 ng/L; p = 0.04), while interleukin (IL) 6 and IL-8 were significantly lower compared to the referents. Also pentraxin 3 was significantly lower (3558 vs. 4592 ng/L; p = 0.01) in the rock drillers. A dose-response relationship was observed between cumulative exposure to CS and MMP-12, the highest exposed subgroup having significantly higher MMP-12 concentrations than the referents.

Conclusion: Exposure to CS may increase circulating MMP-12 concentrations in a dose-response related fashion. The results may also suggest a down-regulation of pro-inflammatory pathways.

Keywords: Biomarkers; Crystalline silica; Inflammation; Matrix metalloproteinase 12.

MeSH terms

  • Adult
  • Air Pollutants, Occupational / adverse effects
  • Air Pollutants, Occupational / analysis
  • Biomarkers* / blood
  • C-Reactive Protein* / analysis
  • Cross-Sectional Studies
  • Female
  • Humans
  • Inflammation / blood
  • Interleukin-6 / blood
  • Interleukin-8 / blood
  • Male
  • Matrix Metalloproteinase 12* / blood
  • Middle Aged
  • Occupational Exposure* / adverse effects
  • Occupational Exposure* / analysis
  • Particulate Matter / analysis
  • Pulmonary Disease, Chronic Obstructive / blood
  • Serum Amyloid P-Component / analysis
  • Silicon Dioxide*

Substances

  • Silicon Dioxide
  • Biomarkers
  • C-Reactive Protein
  • Matrix Metalloproteinase 12
  • Interleukin-8
  • Serum Amyloid P-Component
  • Particulate Matter
  • PTX3 protein
  • Interleukin-6
  • Air Pollutants, Occupational
  • MMP12 protein, human