Figure 4. This world map was drawn by Flemish
cartographer Abraham Ortelius in 1570.
Today, satellites give us essentially complete knowledge of the earth’s surface
so that one can zoom-in to see a house. In 1570, a map of the world
was needed even though information was limited. Today, we can map the
knowledge domain of occupational toxicology realizing that knowledge
is incomplete and accuracy will increase as we learn more.
The map of Ortelius shows that information was fairly
complete for Europe but incomplete for the western hemisphere.
Likewise, there are areas in the knowledge domain of hazardous
chemicals and occupational diseases in which the information is
relatively complete or incomplete. From animal experiments, case
reports, and epidemiological studies, we now have fairly complete
information about the potential adverse effects of the most commonly
used chemicals, for example, the several hundred chemicals profiled by
ACGIH. Metals are typically profiled as groups, for example,
"arsenic and inorganic compounds." See this list
of diseases caused by metal compounds.
For occupational diseases, see this list
in Haz-Map. There is little doubt about the occupational nature of
205 of the 239 diseases in Haz-Map. There is a consensus in occupational
medicine textbooks that these occupational diseases are caused by
specific
hazardous agents, and the diseases can be prevented by good occupational
hygiene practices. The debatable categories are occupational cancers,
reproductive diseases, and "more research needed." A rule in
Haz-Map accepts as established occupational cancers all designated as
"known human carcinogens" by IARC (International Agency for
Research in Cancer) and which occur after occupational exposure.
Like a mapmaker, the domain expert who designs an intelligent
database first outlines the domain and then adds details, starting
with the most prominent features. The intended use of the map
determines the content. Instead of simply passing on the explosion of
information, it could be intelligently mapped prior to dissemination.
The CDC has called the product of this kind of mapping process,
"synthesized, knowledge-based information." [MMWR, Feb18,
2000/49(06); 118-120.]