Toxicological profile for barium and barium compounds

23 

BARIUM AND BARIUM COMPOUNDS 

3.  HEALTH EFFECTS 

the vehicle used, purity of the test material, duration and frequency of exposure, and number of animals 

tested (Hicks et al. 1986).  The second animal study consisted of several experiments, but was generally 

limited in that the authors provided few details regarding experimental methods, exposure conditions, and 

test results, and no information as to the number of animals tested, purity of the test material, or statistical 

methods used; furthermore, in some experiments, it was not clear whether or not control animals were 

used (Tarasenko et al. 1977).  The third study examined a limited number of end points (Cullen et al. 

2000).  In view of the major limitations associated with the available case reports and studies, results from 

these reports should be regarded as providing only preliminary and/or suggestive evidence that acute, 

intermediate, and chronic inhalation exposure to barium may potentially be associated with adverse health 

effects.  Findings from the various case reports and animal studies are briefly described below. 

3.2.1.1  Death 

No studies were located regarding death in humans or animals after inhalation exposure to barium. 

3.2.1.2  Systemic Effects  

No studies were located regarding endocrine, dermal, or ocular effects in humans or animals after 

inhalation exposure to barium. 

Respiratory Effects.

    Two reports of workers exposed chronically to dust from barium sulfate 

demonstrated that this exposure had a minor effect on the lungs.  In one study, a benign pneumo­

noconiosis was observed in several factory workers (Doig 1976).  In a second study in which workers 

were exposed by mining barium sulfate, silicosis was observed but was attributed to inhalation of quartz 

(Seaton et al. 1986).  In contrast, a study of workers chronically exposed to barium carbonate dust 

reported no respiratory symptoms attributable to barium exposure (Essing et al. 1976).  X-ray analysis of 

the lungs also showed no abnormalities attributable to barium dust. 

Studies regarding respiratory effects in animals following inhalation exposure to barium are limited to 

three reports (Cullen et al. 2000; Hicks et al. 1986; Tarasenko et al. 1977).  Pulmonary lesions 

(perivascular and peribronchial sclerosis and focal thickening of the interalveolar septa) were observed in 

rats exposed to 3.6 mg barium/m

3

 as barium carbonate dust 4 hours/day, 6 days/week for 4 months 

(Tarasenko et al. 1977).  Bronchoconstriction was reportedly noted in guinea pigs following inhalation for 

an unspecified period of time to 0.06 mg barium/m

3

/minute as aerosolized barium chloride solution 

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24 

BARIUM AND BARIUM COMPOUNDS 

3.  HEALTH EFFECTS 

(Hicks et al. 1986).  In contrast to these finding, no adverse histological alterations were observed in the 

lungs of rats exposed to 44.1 mg barium/m

3

 as barium sulfate for 119 days (Cullen et al. 2000). 

Cardiovascular Effects. 

Three of 12 workers chronically exposed to barium carbonate dust had 

elevated blood pressure and 2 workers had ECG abnormalities (Essing et al. 1976).  However, it is 

unknown whether this represented an increased incidence because no comparison with a control 

population was performed.  Increased blood pressure and cardiac irregularities were reportedly observed 

in guinea pigs exposed by inhalation for an unspecified period of time to 0.06 mg barium/m

3

/minute as 

aerosolized barium chloride solution (Hicks et al. 1986).  Tarasenko et al. (1977) reported a 32% increase 

in arterial pressure and alterations in ECG readings suggestive of disturbances in heart conductivity 

following proserine administration in rats exposed to 3.6 mg barium/m

3

 as barium carbonate; no ECG 

alterations were observed prior to proserine administration. 

Gastrointestinal Effects.

    Abdominal cramps, nausea, and vomiting were experienced by a 22-year­

old factory worker accidentally exposed by acute inhalation to a large but unspecified amount of barium 

carbonate powder (Shankle and Keane 1988).  No animal studies were located regarding gastrointestinal 

effects in animals after inhalation exposure to barium. 

Hematological Effects.

    Altered hematological parameters were observed in rats following inhalation 

for an intermediate exposure period to 3.6 mg barium/m

3

 as barium carbonate dust (Tarasenko et al. 

1977).  Reported changes included decreased blood hemoglobin and thrombocyte count.  

Musculoskeletal Effects.

    After accidental exposure to a large amount of barium carbonate powder 

by acute inhalation, a 22-year-old factory worker developed progressive muscle weakness and paralysis 

of the extremities and neck (Shankle and Keane 1988); this is likely due to the low serum potassium level 

rather than a direct effect on muscle tissue.  X-ray analysis of the bones and skeletal muscles of the pelvis 

and thighs of workers chronically exposed to barium carbonate dust revealed no apparent build up of 

insoluble barium in these tissues (Essing et al. 1976).  No studies were located regarding musculoskeletal 

effects in animals after inhalation exposure to barium. 

Hepatic Effects.

    No studies were located regarding hepatic effects in humans after inhalation 

exposure to barium.  Impaired detoxifying function of the liver was noted in rats exposed to 3.6 mg 

barium/m

3

 as barium carbonate dust (Tarasenko et al. 1977).  No other details were reported. 

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