Blood levels brain accumulation

Jaundice (yellow color of skin, whites of the eyes) may occur when blood levels of bilirubin exceed normal (icterus). Jaundice may be characterized by an increase in unconjugated (indirect) bilirubin, conjugated (direct) bilirubin, or both. Accumulation of bilirubin (usually unconjugiated) in the brain (kernicterus) may result in death. When conjugated bilirubin increases, it may be excreted, giving a deep yeUow-red color to the urine. Examples of conditions associated with increased bilirubin and jaundice include the following. 

Tin has also been detected in blood and brain tissue after exposure to high dose levels. Blood tin increased in 1 week in rats that ingested tin in drinking water at a dose of 42.7 mg tin/kg/day as stannous chloride, but did not differ from control levels when rats were administered a dose of 8.5 mg tin/kg/day (Savolainen and Valkomen 1986). Tin has also been detected in brain tissue and levels increased with increased exposure duration. Brain tin accumulated at a dose of 42.7 mg tin/kg/day during an 18-week exposure period but did not increase during this same period at a dose of 8.5 mg tin/kg/day (Savolainen and Valkomen 1986). 

In 1982 selective retention of phenolic PCB metabolites was first observed in the intraluminal uterine fluid of pregnant mice after administration of CB-31, using whole body autoradiography and subsequent chemical analysis [36]. Administration of CB-77 to pregnant mice resulted in a dramatic accumulation of a phenolic metabolite in fetal soft tissue [191]. The retained metabolite was shown to be 4-OH-3,3, 4, 5-tetraCB and localized in the blood in both the fetus and in adult mice [73], A metabolism study of the structurally related CB-105 in mice showed significant retention of the para-substituted hydroxylated metabolite 4-OH-CB-107 in blood [71]. The 4-OH-CB 107 was also shown to be retained in blood from rats administered Aroclor 1254 [39], and was observed at high levels in blood and brain tissue from rat fetuses exposed in utero [192],... 

There is a significant accumulation of fluorocarbons in the brain, liver, and lungs compared to blood levels, signifying a tissue distribution of fluorocarbons similar to that of chloroform. Fluorocarbons are concentrated in body fat where they are slowly released into blood at a concentration that should not cause any risk of cardiac sensitization. 

Loss of CFC-113 from tissues is rapid during the postexposure period with virtually 100% clearance within 24 h of exposure. Freons are eliminated entirely by the respiratory tract. Chlorofluorocarbon compounds partition preferentially into lipid-rich tissues and are poorly metabolized. Significant accumulation occurs in brain, liver, and lung tissues compared to blood levels. 

The distribution of free carbon disulfide and bound carbon disulfide liberated by acid hydrolysis was investigated in the tissues of white rats after a large, single subcutaneous dose (approximately 361 mg/kg) of carbon disulfide (Bartonicek 1957, 1959). Results of these studies indicate that following absorption, free carbon disulfide is rapidly removed from the blood and tissues. Negligible blood levels were present 11 hours after the dose was administered (Bartonicek 1957, 1959). Initially, free carbon disulfide accumulated in the blood, adrenals, and brain, but levels in the organs rapidly decreased, and only very small amounts were present after 10-16 hours. 

Of all turnover rates in the human body, the total excretion rate seems to be the lowest. This means that the body can be looked upon as a one-compartment system in which the intake is balanced by the excretion. In 1968 (Berglund and Berlin, 1969), we therefore proposed a model for the mercury accumulation in the human body, a model which has been widely used (see Fig. 8). However, it may be pointed out that this model is an approximation and valid pnly at non-toxic dose le vels. The indications from animal experiments are that at increasing dose levels the elimination rate goes down. Close to toxic blood levels the brain shows an increasing tendency to accumulate methyl mer-... 

One of the bile pigments which results from the breakdown of hemoglobin. Normally, it is excreted into the intestine with the bile. However, blockage of the biliary tract leads to accumulation of bile in the liver and blood. The buildup of pigment often imparts a yellow color to the skin (a condition called jaundice). Newborn babies are particularly prone to brain damage by elevated blood levels of bilirubin. 

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