Toxicological profile for barium and barium compounds

3.  HEALTH EFFECTS 

Figure 3-3.  Existing Information on Health Effects of Barium and Barium 

Compounds 

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BARIUM AND BARIUM COMPOUNDS 

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79 

BARIUM AND BARIUM COMPOUNDS 

3.  HEALTH EFFECTS 

There is little information regarding health effects in humans following inhalation, oral, or dermal 

exposure to barium and barium compounds (Figure 3-3).  Inhalation studies are limited to several case 

reports of individuals exposed acutely or chronically through occupational exposure (Doig 1976; Essing 

et al. 1976; Seaton et al. 1986; Shankle and Keane 1988).  A number of case reports of acute oral 

exposure to high doses of barium have been identified (Das and Singh 1970; Deng et al. 1991; Diengott et 

al. 1964; Downs et al. 1995; Gould et al. 1973; Jha et al. 1993; Koch et al. 2003; Lewi and Bar-Khayim 

1964; McNally 1925; Ogen et al. 1967; Phelan et al. 1984; Talwar and Sharma 1979; Wetherill et al. 

1981).  Additionally, there is information from a single intermediate-duration experimental study (Wones 

et al. 1990) and several human epidemiological studies or statistical studies examining mortality and 

morbidity rates in communities having exposure to barium through drinking water supplies (Brenniman 

and Levy 1985; Brenniman et al. 1979a, 1979b, 1981; Elwood et al. 1974; Schroeder and Kraemer 1974).  

Dermal studies are limited to one case report of an exposed individual (Stewart and Hummel 1984). 

The majority of studies conducted on animals have been oral exposure studies (Figure 3-3).  Available 

inhalation studies with experimental animals (Hicks et al. 1986; Tarasenko et al. 1977) can only suggest 

information on the health effects of barium because these studies have a number of limitations and 

deficiencies; a third inhalation study (Cullen et al. 2000) is limited to the examination of the respiratory 

tract.  The available oral studies have examined a number of end points, although most studies focused on 

various systemic effects for acute (Borzelleca et al. 1988; Boyd and Abel 1966; Tardiff et al. 1980), 

intermediate (Dietz et al. 1992; McCauley et al. 1985; NTP 1994; Perry et al. 1983, 1985, 1989; 

Tarasenko et al. 1977; Tardiff et al. 1980), and chronic exposure (Kopp et al. 1985; McCauley et al. 1985; 

NTP 1994; Perry et al. 1983, 1985, 1989; Schroeder and Mitchener 1975a, 1975b).  Dermal studies with 

experimental animals are limited to one skin irritation study (Tarasenko et al. 1977) and one study 

evaluating the tumor-promoting activity of barium (Van Duuren et al. 1968). 

3.12.2  Identification of Data Needs 

Acute-Duration Exposure.

    There are limited data on the acute toxicity of barium following 

inhalation, oral, or dermal exposure.  Data on the toxicity of inhaled barium are limited to a human 

experimental study in which welders were exposed to fumes from barium-containing electrodes 

(Zschiesche et al. 1992), a case of a worker exposed to a large amount barium carbonate dust (Shankle 

and Keane 1988), and a study in which guinea pigs were exposed to a single concentration of barium 

chloride for unspecific amount of time (Hicks et al. 1986).  Although none of these studies are suitable for 

derivation of an MRL, the Hicks et al. (1986) study does identify two potential end points (increased 

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BARIUM AND BARIUM COMPOUNDS 

3.  HEALTH EFFECTS 

blood pressure and bronchoconstriction).  Additional inhalation studies are needed to fully evaluate the 

toxicity of barium and establish concentration-response relationships. 

Most of the available information on the acute toxicity of barium comes from human case reports 

involving oral exposure to soluble barium compounds and oral toxicity studies in animals.  There are a 

number of case reports of individuals accidentally or intentionally ingesting large doses of barium (Das 

and Singh 1970; Deng et al. 1991; Diengott et al. 1964; Downs et al. 1995; Gould et al. 1973; Jha et al. 

1993; Koch et al. 2003; Lewi and Bar-Khayim 1964; McNally 1925; Ogen et al. 1967; Phelan et al. 1984; 

Talwar and Sharma 1979; Wetherill et al. 1981).  In general, dose levels were not reported; based on the 

severity of the observed effects, it is likely that the doses were very high.  The observed effects included 

effects associated with hypokalemia (cardiac arrest, ventricular tachycardia, muscle weakness, and 

paralysis), gastrointestinal distress (vomiting, gastric pain, and diarrhea), and kidney damage (hemoglobin 

in the urine, renal insufficiency, degeneration, and acute renal failure).  Several studies in experimental 

animals have examined the acute oral toxicity of barium chloride (Borzelleca et al. 1988; Tardiff et al. 

1980).  These studies have determined LD

50

 values and evaluated potential systemic, neurological, and 

reproductive end points.  These studies have not consistently identified targets of toxicity or adverse 

effect levels.  The available data were considered inadequate for derivation of an acute oral MRL.  

Human data consistently identify the gastrointestinal tract as a target of barium toxicity; most case reports 

of individuals ingesting soluble barium compounds report vomiting, diarrhea, and/or abdominal pain as 

one of the early signs of toxicity.  However, none of the animal studies have adequately investigated this 

end point; rodents are not a good model for examining gastrointestinal irritation.  Animal studies are 

needed to identify the critical targets of barium toxicity and establish dose-response relationships; these 

studies should include a more appropriate animal model for investigating potential gastrointestinal effects.  

Two studies have examined the dermal toxicity of barium.  One is a case report on an individual burned 

with molten barium chloride (Stewart and Hummel 1984); extrapolation of the results of this study to 

environmental exposure scenarios is complicated by the thermal burns.  Tarasenko et al. (1977) examined 

the dermal and ocular toxicity of barium carbonate in several animal species.  Poor reporting of the 

experimental design and results limits the interpretation of the study.  Additional dermal toxicity studies 

are needed for several barium compounds to confirm the Tarasenko et al. (1977) study findings that 

barium is a local irritant and to establish the existence of remote toxicity. 

Intermediate-Duration Exposure.    

No human studies have examined the toxicity of barium in 

humans following intermediate-duration inhalation exposure.  Two animal studies have been identified 

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