Toxicological profile for barium and barium compounds

28 

BARIUM AND BARIUM COMPOUNDS 

3.  HEALTH EFFECTS 

significantly altered in female mice exposed to 0.95 mg barium/kg/day (Schroeder and Mitchener 1975b) 

or male or female rats exposed to 0.7 mg barium/kg/day as barium acetate in drinking water (Schroeder 

and Mitchener 1975a). 

LD

50 

values and reliable LOAEL values for death in each species and duration category are recorded in 

Table 3-1 and plotted in Figure 3-1. 

3.2.2.2  Systemic Effects  

The highest NOAEL values and all reliable LOAEL values for systemic effects in each species and 

duration category are recorded in Table 3-1 and plotted in Figure 3-1. 

Respiratory Effects.

    Limited data are available regarding respiratory effects in animals following 

oral barium exposure.  Fluid in the trachea was observed in rats receiving a single gavage dose of 198 mg 

barium/kg as barium chloride (Borzelleca et al. 1988).  However, this effect was not observed when rats 

were dosed with 198 mg barium/kg/day as barium chloride for 10 days (Borzelleca et al. 1988).  No 

significant alterations in lung weights, gross lesions, or histopathological alterations were observed in the 

respiratory tracts of rats and mice exposed to doses as high as 110 or 70 mg barium/kg/day, 180 or 

450 mg barium/kg/day, or 60 and 160 mg barium/kg/day for intermediate or chronic durations, 

respectively (McCauley et al. 1985; NTP 1994; Tardiff et al. 1980) or lifetime exposure to 0.7 or 0.95 mg 

barium/kg/day, respectively, as barium acetate via drinking water (Schroeder and Mitchener 1975a).   

Cardiovascular Effects.

    As demonstrated in numerous case reports, acute exposure to presumably 

high doses of barium carbonate, barium sulfate, or barium chloride can result in serious effects on heart 

rhythm.  Barium adversely affects cardiac automaticity resulting in ventricular tachycardia and other 

disruptions of rhythm (Deng et al. 1991; Diengott et al. 1964; Downs et al. 1995; Gould et al. 1973; Jha et 

al. 1993; Koch et al. 2003; Silva 2003; Talwar and Sharma 1979; Wetherill et al. 1981).  Hypotension has 

also been reported in some cases (Koch et al. 2003; Talwar and Sharma 1979).  The likely cause of these 

effects was barium-induced hypokalemia. 

Several human studies have investigated a possible association between exposure to low levels of barium 

and alterations in blood pressure and cardiac rhythms.  In a small-scale (11 subjects) study of individuals 

exposed to 0.1 or 0.2 mg barium/kg/day as barium chloride in drinking water for 4 weeks, no significant 

alterations in blood pressure or ECG readings were found (Wones et al. 1990).  There was no significant  

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Table 3-1  Levels of Significant Exposure to Barium  - Oral 

Exposure/ 

Duration/ 

a 

Key to 

Figure 

Species 

(Strain) 

Frequency 

(Route) 

ACUTE EXPOSURE 

Death 

1 

Rat 

(Sprague-

Dawley) 

once 

(GW) 

System 

NOAEL 

(mg/kg/day) 

Less Serious 

(mg/kg/day) 

LOAEL 

Serious 

(mg/kg/day) 

198  (death in 15/20 rats) 

Reference 

Chemical Form 

Borzelleca et al. 1988 

Barium chloride 

Comments 

2 

Rat 

(Sprague-

Dawley) 

once 

(GW) 

269 F  (LD50 in females) 

Borzelleca et al. 1988 

Barium chloride 

3 

Rat 

(NS) 

once 

(GW) 

132  (LD50 adult) 

220  (LD50 weanling) 

Tardiff et al. 1980 

Barium chloride 

Systemic 

4 

Rat 

(Sprague-

Dawley) 

10 d 

1 x/d 

(GW) 

Resp 

198 

Borzelleca et al. 1988 

Barium chloride 

Cardio 

198 

Gastro 

198 

Hemato 

198 

Hepatic 

Renal 

198 

198 

Ocular 

198 

Bd Wt 

198 

29

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Table 3-1  Levels of Significant Exposure to Barium  - Oral 

(continued) 

Exposure/ 

LOAEL 

Duration/ 

a 

Key to  Species 

Frequency 

NOAEL 

Less Serious 

Serious 

Reference 

Figure  (Strain) 

(Route) 

System 

(mg/kg/day) 

(mg/kg/day) 

(mg/kg/day) 

Chemical Form 

Comments 

5 

Rat 

(Sprague-

Dawley) 

once 

(GW) 

Resp 

66 

198  (fluid in trachea) 

Borzelleca et al. 1988 

Barium chloride 

Cardio 

198 

Gastro 

66 

198  (inflammation of small 

and large intestine) 

Hemato 

198 

Hepatic 

66 

198  (decreased liver/brain 

weight ratio; darkened 

liver) 

Renal 

66 

198  (increased kidney/body 

weight ratio) 

Ocular 

66 

198  (ocular discharge) 

Bd Wt 

66 

198  (decreased body weight) 

Immuno/ Lymphoret 

6 

Rat 

(Sprague-

Dawley) 

Neurological 

7 

Rat 

(Sprague-

Dawley) 

10 d 

1 x/d 

(GW) 

10 d 

1 x/d 

(GW) 

Other 

198 

198 

198 

Borzelleca et al. 1988 

Barium chloride 

Borzelleca et al. 1988 

Barium chloride 

Evaluated weight and 

occurrence of gross 

lesions in thymus. 

30

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