Manganese tissue concentrations

Manganese is a normal component of human and animal tissues and fluids. In humans, most tissue concentrations range between 0.1 and 1 pg manganese/g wet weight (Sumino et al. 1975 Tipton and Cook 1963), with the highest levels in the liver, pancreas, and kidney and the lowest levels in bone and fat (see Table 2-3). Manganese levels in the blood, urine, and serum of healthy, unexposed subjects living in the... 

Several studies have determined the distribution of manganese in tissues of animals following i.v. administration of mangafodipir. Grant et al. (1999) reported that in rats injected with 2 times the clinical dose of [ Mn] mangafodipir (0.55 mg manganese/kg) the carcass retained 8% of the label, and the tissues retained 7% of the label individual tissue concentrations of manganese were not reported. 

Manganese. The adult human body contains ca 10—20 mg of manganese (124,125), widely distributed throughout the body. The largest Mg " concentration is in the mitochondria of the soft tissues, especially in the Hver, pancreas, and kidneys (124,126). Manganese concentration in bone varies widely with dietary intake (126) (see Table 10). 

Gooneratne, S.R. and D.A. Christensen. 1989. A survey of maternal and fetal tissue zinc, iron, manganese and selenium concentrations in bovine. Canad. Jour. Anim. Sci. 69 151-159. 

Stable aerosols of fine particulates as well as vapors constitute the greatest health risk because of the likelihood of pulmonary absorption. Correlations between trace element pollution and their concentrations in biological fluids or tissue are not uncommon and have been documented for arsenic (62) and lead (63). Man can absorb 75-85% of inhaled mercury vapor at concentrations of 50-350 pg/M3 (64) and even more at lower concentrations (65). Certain aerosols like vanadium, iron, manganese, and lead may contribute to the formation of secondary atmospheric pollutants (52, 66). 

Manganese occurs in the liver of the animal body. Even though the amount ol manganese present in mammalian tissues is very small, its concentration seems to be accurately controlled by elaborate mechanisms These mechanisms function primarily by promoting the excretion of excesses of the element from the body rather than by regulating the amounts ol manganese the body absorbs. The mechanisms are located in the liver and on the mucosa of the gut. In cases of manganese toxicity, it is assumed that these mechanisms become saturated. 

A recent study by Sanchez et al. (1997) found significant age-related effects on aluminum interactions with essential elements (e g., calcium, magnesium, zinc). Decreases in concentration of some essential elements in a number of tissues were observed in young rats orally exposed to aluminum lactate (as compared to adults) the decreases included liver and spleen calcium levels, bone magnesium levels, and brain manganese levels. 

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