Using environmental forensic microscopy in exposure science

Our plain-English summary of Using environmental forensic microscopy in exposure science, by J.R. Millette, R.S. Brown, W.B. Hill (Journal of Exposure Science & Environmental Epidemiology, 2008).

The study

• Authors: J.R. Millette, R.S. Brown, W.B. Hill
• Journal: Journal of Exposure Science & Environmental Epidemiology
• Published: 2008;18(1):20-30
• Cited by: 3 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Environmental forensic microscopy investigations are based on the methods and procedures developed in the fields of criminal forensics, industrial hygiene and environmental monitoring. Using a variety of microscopes and techniques, the environmental forensic scientist attempts to reconstruct the sources and the extent of exposure based on the physical evidence left behind after particles are exchanged between an individual and the environments he or she passes through. This article describes how environmental forensic microscopy uses procedures developed for environmental monitoring, criminal forensics and industrial hygiene investigations. It provides key references to the interdisciplinary approach used in microscopic investigations. Case studies dealing with lead, asbestos, glass fibers and other particulate contaminants are used to illustrate how environmental forensic microscopy can be very useful in the initial stages of a variety of environmental exposure characterization efforts to eliminate some agents of concern and to narrow the field of possible sources of exposure.

In plain English

This was a descriptive methods article illustrated with case investigations, not a study of a group of people. The authors described environmental forensic microscopy, which uses light and electron microscopes and procedures from criminal forensics, industrial hygiene and environmental monitoring to identify particles in dust and trace their sources. Several examples came from earlier published work. In one asbestos example, attic dust below asbestos-containing fireproofing contained gypsum, vermiculite and chrysotile asbestos, some in small clumps consistent with the fireproofing. The analysis found no evidence of other asbestos-containing products, such as floor tile fragments, and concluded that the fireproofing was the primary source of asbestos in the attic surface dust. Other examples included cat hairs in office dust and thousands of mold spores in California tunnel dust. The authors noted that tracing sources of an element at parts-per-million levels is not feasible by microscopy unless the particles of interest can be concentrated. They also noted that, apart from fiber concentrations, measuring amounts usually needs other methods. The authors concluded that the approach can be very useful early in exposure assessments to rule out some agents and narrow possible sources.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Descriptive methods article (narrative overview) illustrated with case investigations, some new and some from previously published investigations
• Who was studied: No study population. The article uses dust and particle samples from individual case investigations, such as an attic, an office, a municipal tunnel in California and a residence in Georgia, USA.
• Exposure: Various particles found in dust, including chrysotile asbestos from asbestos-containing fireproofing, lead, glass fibers, mold spores, cat hair, soot, metal particles and nanoparticles
• Main results:
  • Attic case: dust on surfaces below asbestos-containing fireproofing contained gypsum, vermiculite and chrysotile asbestos, including small aggregates of all three.
  • Attic case: the dust analysis found no evidence of other asbestos-containing products, such as floor tile fragments.
  • Attic case: the forensic analysis concluded that the fireproofing was the primary source of the asbestos in the dust on the attic surfaces.
  • Office case: a tape-lift dust sample from the office of a woman with apparent allergic symptoms showed many cat hairs. She was allergic to cats.
  • Tunnel case: dust from a California tunnel where municipal maintenance workers reported respiratory symptoms contained thousands of microscopic mold spores. Earlier chemical analysis of the dust had shown no obvious toxic elements.
  • A glass fiber was found by transmission electron microscopy in human lung tissue. The tissue had been processed with a bleach digestion method developed for asbestos lung burden testing.
• The authors' conclusion: The authors concluded that environmental forensic microscopy can be very useful in the early stages of an exposure assessment, to eliminate some agents of concern and narrow the possible sources of exposure.
• Limitations the authors state:
  • Microscopy cannot practically trace sources of an element present at part-per-million levels unless the particles of interest can be concentrated.
  • Except for measuring fiber concentrations, quantifying the amount of a contaminant usually requires other analytical methods.

Topics

Medical terms in this study, explained in our Lexicon: Industrial Hygiene, Environmental Exposure.

Related studies

• Forensic Epidemiology in Italy: principles and practice — V. Chiesa, A. Odone, et al. (2017)
• Quantifying health effects from the combined action of low-level radiation and other environmental agents: can new approaches solve the enigma? — W. Burkart, G.L. Finch, et al. (1997)
• A comparison of historic asbestos measurements using a thermal precipitator with the membrane filter-phase contrast microscopy method — G. Burdett (1998)
• Forensic detection and investigation of occupational-environmental disease — T. Ehrenreich, I.J. Selikoff (1980)
• The wild rat as sentinel animal in the environmental risk assessment of asbestos pollution: a pilot study — M. Ardizzone, C. Vizio, et al. (2014)
• Environmental contamination of chrysotile asbestos and its toxic effects on antioxidative system of Lemna gibba — A.K. Trivedi, I. Ahmad, et al. (2007)

Browse more research in Journal of Exposure Science & Environmental Epidemiology, or return to medical research.