TOXICOLOGICAL PROFILE FOR BARIUM AND COMPOUNDS ...

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2. HEALTH EFFECTS
Washington 1983). However, there are not enough similar studies on different
species to determine this with certainty. Studies on different species would
increase confidence in the reliability of the existing database.
Mitigation of Effects. Methods have been reported for limiting oral and
dermal absorption of barium compounds (Bronstein and Currance 1988; Dreisbach
and Robertson 1987; Haddad and Winchester 1990) and for counteracting the
hypokalemia that is produced by barium in acute high-level exposure situations
(Dreisbach and Robertson 1987; Haddad and Winchester 1990; Proctor et al.
1988). Contradictions exist in the literature regarding the efficacy or
desirability of administering emetics (Bronstein and Currance 1988; Ellenhorn
and Barceloux 1988; Haddad and Winchester 1990). Additional studies
clarifying this issue would be helpful. Also, studies directed at finding a
more efficient way to remove barium from the body would be useful. It is
unclear whether mechanisms other than hypokalemia contribute to the toxic
effects produced in acute high-level exposure situations. Additional
information on the mechanisms responsible for the toxic effects of barium
could aid in the development of effective treatments. Magnesium has been
reported to antagonize the neuromuscular effects (Dreisbach and Robertson
1987). Additional studies examining the efficacy of administering soluble
magnesium salts to antagonize the effects of barium would also be helpful. No
information was located on treatment strategies for long-term low-level
exposures. Research on procedures for mitigating such chronic exposure
situations would be helpful.
2.9.3 On-going Studies
A 2-year lifetime study of barium chloride in drinking water was
conducted in rats and mice by the National Toxicology Program. The study was
completed in the 1987 fiscal year, however, the histopathological section is
still in progress (NTP 1990).
One on-going study regarding health effects of barium was reported in
the FEDRIP (1989) database. An epidemiological study is presently being
conducted by L. Frohman. The relationship between barium in drinking water
and the cardiovascular risk effects to humans is being assessed. No other
information was obtained.