Barium human tissue

Another consideration for estimating the toxicity of barium, as well as other compounds, is that the toxicity may well be altered by interactions with other toxicants. Specifically, barium would be expected to have reciprocal interactions with other trace metals found in the environment and in human tissues (Berggren et al. 1983 Foster et al. 1977 Jaklinski et al. 1967 Roza and Berman 1971 Schott and McArdle 1974). Considerations of these interactions should be made when designing future tests of barium and other compounds. 

Exposure Levels in Humans. Barium can be detected in blood, urine, feces, and biological tissues (Mauras and Allain 1979 Schramel 1988 Shiraishi et al. 1987). However, there are no data correlating barium levels in tissues and fluids with exposure levels. Additional data are needed on levels of barium in human tissues and fluids following occupational and general population exposure, particularly at hazardous waste sites. This information may be useful in establishing exposure indices for these populations. 

Sowden EM. 1958. Trace elements in human tissue 3. Strontium and barium in non-skeletal tissue. Biochem J 70 712-715. 

Sowden EM, Stitch SR. 1957. Trace elements in human tissue 2. Estimation of the concentrations of stable strontium and barium in human bone. Biochem J 67 104-109. 

The barium content of human tissues is dependent on age. For example, in adults the liver contained barium levels of 4-20 mg kg dry matter, whereas in children the typical liver barium content was much higher, at 144 mg kg The majority of tissue barium is accumulated in the skeleton, with typical adult levels ranging from 16 to 95 mg kg dry matter. Very high barium contents were also determined in the prostate gland of children, with up to 1.3gkg dry matter in infants (Jaritz 1998). Other sources have described lower levels of barium in human tissues however... 

The average adult human body contains 22 mg Ba, of which 93% is present in bone (47). The remainder is widely distributed throughout the soft tissues of the body in very low concentrations. Accumulation of barium also takes place in the pigmented parts of the eyes. 

Humans can be exposed to barium in the air, water, or food. Numerous studies exist that discuss the distribution of barium in the human body, but they do not always specify route of exposure. It is presumed that the majority of the barium intake is from the oral route. Barium occurs mostly (over 93%) in the bones and teeth of humans. Very little is found in blood plasma or soft tissues but, when it is detected in the organs, it is found in the eye, lungs, skin, and adipose tissue in humans at less than 1 % of total body weight (Schroeder et al. 1972). This information is supported by a number of studies (Bauer et al. 1957 Losee etal. 1974 Miller et al. 1985 Moloukhia and Ahmed 1979 Sowden 1958 Sowden and Stitch 1957 Sowden and Pirie 1958). 

Acute intravasation of barium sulfate into the circulatory system of an adult female patient following a barium enema procedure caused the compound to be deposited in blood vessels throughout the body, including the lungs, and resulted in respiratoryfailure (Cove and Snyder 1974). Acute parenteral administration of barium compounds to animals has been shown to result in paralysis of the respiratory muscles (Roza and Berman 1971). Similar respiratory paralysis is frequently encountered in cases of acute exposure in humans and animals by ingestion or inhalation. Intratracheal administration of barium sulfate into rat lungs produced a mild inflammatory reaction (Huston et al. 1952). Barium sulfate could not be removed by either polymorphonuclear leukocytes or monocytes. A tissue reaction followed however, no fibrosis was observed. Since this mode of entry is similar to inhalation, these results may be significant for cases of inhalation exposure. 

Two case studies of acute intrusion of barium sulfate into the peritoneal space during barium enema examination of four men showed barium sulfate caused an acute inflammatory tissue response (Kay 1954 Yamamura et al. 1985), and in one case resulted in formation of a fibrous granuloma (Kay 1954). This is an extremely rare mode of entry and not of significant concern for individuals exposed at a hazardous waste site. Increased fluid accumulation in the intestinal lumen of rats was observed after intraperitoneal injection of barium chloride (Hardcastle et al. 1983b, 1985) however, this observation is not significant for individuals exposed at hazardous waste sites because of the route of exposure and because there has been no documentation of this effect occurring in humans following normal exposure routes. 

One in vitro study on rat renal tissue homogenate showed barium weakly inhibited the sodium-potassium-adenosine triphosphatase enzyme system (Kramer et al. 1986). A second study on mouse kidney tubules showed barium chloride could depolarize the membrane and inhibit potassium transport (Volkl et al. 1987). A similar defect in cell membrane transport in humans could be responsible for the renal involvement observed in some cases of acute barium poisoning. 

In a study of the barium content of the major human organs and tissues, the total body content of barium for a 70-kg adult male was estimated to be about 22,000 pg (ICRP 1974 Schroeder et al. 1972). Ninety-three percent of this barium was found in bone and connective tissue. Large amounts of the remaining 7% existed in fat, skin, and lungs (ICRP 1974 Schroeder et al. 1972). 

Piezoelectricity, from Greek Klet elv meaning to press, to squeeze [41], is the interplay between mechanical and electrical features of a material or a device. Changing one will impact the other. There are different types of materials that show these properties. Quartz, topaz, and tourmaline minerals human and animal bone tissue different proteins Rochelle salts (sodium, potassium tartrate tetrahydrate) barium titanate, lead zirconate titanate, PZT and the polymer poly (vinyUdene fluoride) (PVDF), are some examples. Piezoelectricity, compared to many other areas of science, was relatively recently discovered, by Jacques and Pierre Curie [42] working with quartz among other minerals. 

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