Metal additive manufacturing and possible clinical markers for the monitoring of exposure-related health effects

PLoS One. 2021 Mar 18;16(3):e0248601. doi: 10.1371/journal.pone.0248601. eCollection 2021.

Abstract

Additive manufacturing (AM) includes a series of techniques used to create products, in several different materials, such as metal, polymer or ceramics, with digital models. The main advantage of AM is that it allows the creation of complex structures, but AM promises several additional advantages including the possibility to manufacture on demand or replacing smaller worn parts by directly building on an existing piece. Therefore, the interest for and establishment of AM is rapidly expanding, which is positive, however it is important to be aware that new techniques may also result in new challenges regarding health and safety issues. Metals in blood and possible clinical effects due to metal exposure were investigated in AM operators at one of the first serial producing AM facilities in the world during two consecutive years with implementation of preventive measures in-between. As comparison, welders and office workers as control group were investigated. Health investigations comprised of surveys, lung function tests, antioxidant activity and vascular inflammation as well as renal- and hepatic function analysis. AM operators had significantly reduced nickel levels in blood (10.8 vs 6.2 nmol/L) as well as improved lung function (80 vs 92% of predicted) from year 1 to year 2. This is in line with previously published results displaying reduced exposure. Blood cobalt and nickel levels correlated with previously reported urinary levels, while blood chromium did not. Multivariate modelling showed that blood cobalt, antioxidant/inflammatory marker serum amyloid A1/serum paraoxonase/arylesterase 1 activity and the hepatic markers aspartate transaminase, alanine transaminase, and alkaline phosphatase were higher in AM operators compared to controls. The study show that the selected clinical analyses could function as a complement to metal analyses in biological fluids when investigating exposure-related health effects in AM operators. However, validation in larger cohorts is necessary before more definite conclusions could be drawn.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Air Pollutants, Occupational / adverse effects
  • Biomarkers / blood
  • Biomarkers / urine
  • Case-Control Studies
  • Female
  • Humans
  • Male
  • Metal Workers*
  • Metals / adverse effects*
  • Metals / blood
  • Metals / urine
  • Middle Aged
  • Occupational Diseases / blood
  • Occupational Diseases / diagnosis*
  • Occupational Diseases / etiology
  • Occupational Diseases / urine
  • Occupational Exposure / adverse effects
  • Printing, Three-Dimensional / instrumentation*
  • Respiratory Function Tests

Substances

  • Air Pollutants, Occupational
  • Biomarkers
  • Metals

Grants and funding

The study was supported by AFA Insurance, Sweden in the form of a grant awarded to HK (150246) and Siemens Energy AB, Finspång Sweden in the form of salaries for PA and MLL. The specific roles of these authors are articulated in the ‘author contributions’ section. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.