Airborne asbestos in public buildings

Our plain-English summary of Airborne asbestos in public buildings, by J. Chesson, J. Hatfield, B. Schultz, et al (Environmental Research, 1990).

The study

• Authors: J. Chesson, J. Hatfield, B. Schultz, E. Dutrow, J. Blake
• Journal: Environmental Research
• Published: 1990;51(1):100-7
• Cited by: 16 articles, as counted by NIH iCite
• Read it: PubMed · Publisher
• In J-M's library: Johns-Manville's company medical library held a copy (J-M no. 000005).

Abstract

The U.S. Environmental Protection Agency sampled air in 49 government-owned buildings (six buildings with no asbestos-containing material, six buildings with asbestos-containing material in generally good condition, and 37 buildings with damaged asbestos-containing material). This is the most comprehensive study to date of airborne asbestos levels in U.S. public buildings during normal building activities. The air outside each building was also sampled. Air samples were analyzed by transmission electron microscopy using a direct transfer preparation technique. The results show an increasing trend in average airborne asbestos levels; outdoor levels are lowest and levels in buildings with damaged asbestos-containing material are highest. However, the measured levels and the differences between indoors and outdoors and between building categories are small in absolute magnitude. Comparable studies from Canada and the UK, although differing in their estimated concentrations, also conclude that while airborne asbestos levels may be elevated in buildings that contain asbestos, levels are generally low. This conclusion does not eliminate the possibility of higher airborne asbestos levels during maintenance or renovation that disturbs the asbestos-containing material.

In plain English

In 1987 the U.S. Environmental Protection Agency measured airborne asbestos in 49 federally owned buildings. Six had no asbestos-containing material, six had such material in generally good condition, and 37 had damaged material. Air was sampled inside each building, and outside 48 of them, during normal activity and analyzed by transmission electron microscopy. No asbestos structures were detected in 83% of 387 samples. Median building levels, in structures per cubic centimeter, were less than 0.00001 outdoors, 0.00010 in buildings without asbestos material, 0.00040 in buildings with material in good condition and 0.00058 in buildings with damaged material. A test for an increasing trend gave a P value of approximately 0.05. The highest single sample (0.033 structures per cubic centimeter) came from a building where no asbestos material was found, for unknown reasons. The authors concluded that levels appeared elevated in buildings with asbestos-containing material, highest with damaged material, but were small in absolute magnitude. They noted that higher levels during maintenance or renovation were not ruled out. Comparable Canadian and UK studies reported levels about 10 times higher, for unknown reasons.

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: Air-sampling survey of public buildings grouped by the condition of their asbestos-containing material, with comparison to published Canadian and UK studies
• Who was studied: 49 federally owned U.S. buildings in five regions, sampled in 1987: six with no asbestos-containing material, six with material in good condition and 37 with damaged material
• Exposure: Airborne asbestos structures (fibers, bundles, clusters and asbestos-containing matrices), counted by transmission electron microscopy. Air was sampled over two 8-hour periods during normal building activity. The asbestos-containing materials were thermal system insulation, surfacing material, or both. Fiber types were not reported.
• Main results:
  • Air was sampled at seven indoor locations and one outdoor location per building, except that one building could not be sampled outside (48 outdoor sites) and another had only six indoor sites
  • Of 387 air samples, no asbestos structures were detected in 83%
  • Median of building averages, in structures per cubic centimeter: outdoor less than 0.00001; Category 1 (no asbestos) 0.00010; Category 2 (good condition) 0.00040; Category 3 (damaged) 0.00058
  • All estimated airborne asbestos levels were small in absolute magnitude
  • The permutation test for an increasing trend with building category gave a P value of approximately 0.05
  • Among pairwise comparisons, Category 3 (damaged) versus Category 1 (no asbestos) buildings gave the smallest P value, approximately 0.02. Category 3 versus outdoors gave approximately 0.09. The other comparisons gave 0.18 or greater.
  • The highest single-sample concentration, 0.033 structures per cubic centimeter, was in a Category 1 building where no asbestos-containing material was identified. The reason for this value is unknown.
  • Canadian and UK measurements from comparable studies were approximately 10 times higher than the EPA study's. The reason is unknown.
• The authors' conclusion: The authors concluded that airborne asbestos levels appear elevated in buildings with asbestos-containing material and highest in buildings with damaged material, but that the levels and differences are small in absolute magnitude. They added that this does not rule out higher levels during maintenance or renovation that disturbs the material.
• Limitations the authors state:
  • Buildings were chosen to represent each category, not in proportion to how often each category occurs among all buildings
  • Inspection and sampling protocols were less detailed than those an individual building owner would apply
  • The study did not assess the impact of the asbestos management program GSA was implementing. The authors say this program may have contributed to lower measured levels.
  • P values for pairwise comparisons may be underestimates because they do not account for multiple comparisons

Topics

Medical terms in this study, explained in our Lexicon: Asbestos-Containing Material (ACM), Transmission Electron Microscopy (TEM).

Related studies

• Airborne fiber control in buildings during asbestos material removal by amended water methodology — R.N. Sawyer, A.N. Rohl, et al. (1985)
• Statistical analysis of data on airborne asbestos levels collected in an EPA survey of public buildings — K.S. Crump, D.B. Farrar (1989)
• Asbestos concentrations in public buildings - a preliminary report — J.M. le Guen, G. Burdett (1981)
• Extreme airborne asbestos concentrations in a public building — E. Ganor, A. Fischbein, et al. (1992)
• Airborne asbestos concentrations in buildings — G.J. Burdett, S.A. Jaffrey (1986)
• Composition of heavy metals and airborne fibers in the indoor environment of a building during renovation — M.T. Latif, N.H. Baharudin, et al. (2011)

Browse more research in Environmental Research, or return to medical research.