Asbestos Fibers and Other Elongate Mineral Particles: State of the ...

surveillance investigations. By having the results
of previous studies available in the information
management system, it could be used to
promote the development of an efficient, nonduplicative
research program. It could also be
a resource for data exploration and additional
analyses of accumulated results.
After comprehensive review of current knowledge
and the available data in the above-
described information management system,
the study groups should identify specific aims
and plan, prioritize, and conduct mineralogical,
toxicological, epidemiological, and clinical
research within the general framework laid out
in this Roadmap. Early results will inform the
need for later research and will dictate changes
in priorities and directions needed to accomplish
the overall goals of the research program.
Ongoing research and study on improvements
of the analytical methods currently used for
regulatory purposes should be independent of
other research. However, as surveillance and
exposure assessment efforts proceed, research
on analytical methods should advance the capability
to identify and characterize worker exposures
and to measure relevant exposure parameters
identified by toxicological research.
Eventually, after determinants of EMP toxicity
are more fully elucidated, research should
increasingly focus on sampling and analytical
methods that can be routinely used in compliance
exposure assessment.
4.3 Outcomes
NIOSH will promote integration of the research
goals set forth in this Roadmap into
the industry sector–based and research-to-
practice-focused National Occupational Research
Agenda (NORA), a national program
involving both the public and private sectors.
NIOSH CIB 62 • Asbestos
The goals and objectives of this Roadmap
can be substantially advanced through robust
public-private sector partnership.
The ideal outcome of a comprehensive research
program for asbestos fibers and other EMPs
would be to use the results to develop recommendations
to protect workers’ health that are
based on unambiguous science. Optimally, such
recommendations may specify criteria, such as
a range of chemical composition, dimensional
attributes (e.g., ranges of length, width, and aspect
ratio), dissolution rate/fragility parameters,
and other factors that can be used to indirectly
assess the toxicity of EMPs. It would be particularly
advantageous if the results of the research
could be used to devise a battery of validated
in vitro or short-term in vivo assays with sufficient
predictive value to identify EMPs warranting
concern on the basis of their physical
and chemical properties, without the need for
comprehensive toxicity testing and/or epidemiological
evaluation of each individual EMP.
Newly identified EMPs could be compared to
the criteria to determine a likelihood of toxicity.
Coherent risk management approaches for
EMPs that fully incorporate a clear understanding
of the toxicity could then be developed to
minimize the potential for EMP-related disease
outcomes among exposed workers.
Although it is beyond the scope of this Roadmap,
exploration of the extent to which a
health-protective policy for EMPs could be extended
to SVFs and other manufactured materials,
such as engineered carbon nanotubes
and nanofibers, is warranted. It has been noted
that elongate nanoscale particles (e.g., singlewalled
and multiwalled carbon nanotubes)
cause interstitial fibrosis in mice [Shvedova et
al. 2005; Porter et al. 2009] and that peritoneal
exposure of mice to carbon nanotubes has
been reported to induce pathological responses
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