High blood perfusion

The existing information regarding distribution of PCBs in humans is limited. Nevertheless, based on experimental data obtained in animals (see Section 3.4.2.2) and the known physicochemical properties of PCBs, it is reasonable to assume that the lipid soluble PCBs, once cleared from the bloodstream, will accumulate in highest concentration in fatty tissues. Initially, however, PCBs could accumulate in the liver due to its high blood perfusion rate. The availabiUty of PCBs for retention in fatty tissues is intimately linked to metaboUsm (see Section 3.4.3) therefore, it would be expected that the higher chlorinated PCBs would persist for longer periods of time solubiUzed in fatty tissues. 

The kidney represents a major target for toxic xe-nobiotics due to its role in the control of body fluid and electrolyte homeostasis. The high blood perfusion rate (20% of cardiac output) and the capabiUty to extract, metabolize, secrete and concentrate toxic compounds make the kidneys extremely vulnerable to a... 

In a lung unit with high blood flow and low ventilation (airway obstruction), the level of carbon dioxide is increased and the level of oxygen is decreased. The excess carbon dioxide causes bronchodilation and an increase in ventilation. The reduced oxygen causes vasoconstriction and a decrease in perfusion. In this way, the V/Q ratio is brought closer to one and gas exchange is improved. 

The distribution of a chemical in tissue depends on the binding/par-titioning between circulatory blood and tissues, the transfer across biological membranes and the tissue-blood perfusion. After incorporation, contaminants are distributed from blood to high perfusion tissues (e.g. liver, kidney), then to low perfusion ones (skin, muscle) and finally to lipoidal tissues [2], establishing kinetically different compartments (internal organs > liver > head skin) and different times to equilibrium [18]. Surfactants (LAS, AS, AES, AEO and APEO) have been... 

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