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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2014/07/08 17:41:02」(JST)

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Toxicokinetics (often abbreviated as 'TK') is the description of what rate a chemical will enter the body and what happens to it once it is in the body.

Relation to Pharmacokinetics

It is an application of pharmacokinetics to determine the relationship between the systemic exposure of a compound in experimental animals and its toxicity. It is used primarily for establishing relationships between exposures in toxicology experiments in animals and the corresponding exposures in humans. However, it can also be used in environmental risk assessments in order to determine the potential effects of releasing chemicals into the environment. In order to quantify toxic effects toxicokinetics can be combined with toxicodynamics. Such toxicokinetic-toxicodynamic (TKTD) models are used in ecotoxicology (see ecotoxmodels a website on mathematical models in ecotoxicology).

Similarly, physiological toxicokinetic models are physiological pharmacokinetic models developed to describe and predict the behavior of a toxicant in an animal body; for example, what parts (compartments) of the body a chemical may tend to enter (e.g. fat, liver, spleen, etc.), and whether or not the chemical is expected to be metabolized or excreted and at what rate.

Processes

Four potential processes exist for a chemical interacting with an animal: absorption, distribution, metabolism and excretion (ADME). Absorption describes the entrance of the chemical into the body, and can occur through the air, water, food, or soil. Once a chemical is inside a body, it can be distributed to other areas of the body through diffusion or other biological processes. At this point, the chemical may undergo metabolism and be biotransformed into other chemicals (metabolites). These metabolites can be less toxic than the parent compound. After this potential biotransformation occurs, the metabolites may leave the body, be transformed into other compounds, or continue to be stored in the body compartments.

A well designed toxicokinetic study may involve several different strategies and depends on the scientific question to be answered. Controlled acute and repeated toxicokinetic animal studies are useful to identify a chemical's biological persistence, tissue and whole body half-life, and its potential to bioaccumulate. Toxicokinetic profiles can change with increasing exposure duration or dose. Real world environmental exposures generally occur as low level mixtures, such as from air, water, food, or tobacco products. Mixture effects may differ from individual chemical toxicokinetic profiles because of chemical interactions, synergistic, or competitive processes. For other reasons, it is equally important to characterize the toxicokinetics of individual chemicals constituents found in mixtures as information on behavior or fate of the individual chemical can help explain environmental, human, and wildlife biomonitoring studies. ^[1]

References

^ Szabo DT, Diliberto JJ, Hakk H, Huwe JK, Birnbaum LS (2010). "Toxicokinetics of the flame retardant hexabromocyclododecane gamma: effect of dose, timing, route, repeated exposure, and metabolism". Toxicological Sciences 117 (2): 282–93. doi:10.1093/toxsci/kfq183.

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English Journal

Impact of olive oil phenolic concentration on human plasmatic phenolic metabolites.

Rubió L, Valls RM, Macià A, Pedret A, Giralt M, Romero MP, de la Torre R, Covas MI, Solà R, Motilva MJ.SourceFood Technology Department, XaRTA-TPV, Escuela Técnica Superior de Ingeniería Agraria, University of Lleida, Av/Alcalde Rovira Roure 191, 25198 Lleida, Spain.
Food chemistry.Food Chem.2012 Dec 15;135(4):2922-9. doi: 10.1016/j.foodchem.2012.07.085. Epub 2012 Jul 25.
Three different functional phenol-enriched virgin olive oils (FVOO) were prepared with a phenolic content of 250 (L-FVOO), 500 (M-FVOO), and 750mg (H-FVOO) total phenols/kg. In a randomised, cross-over study with 12 healthy volunteers, the pharmacokinetics of phenolic biological metabolites was asse
PMID 22980891

Liquorice reduced cyclosporine bioavailability by activating P-glycoprotein and CYP 3A.

Hou YC, Lin SP, Chao PD.SourceSchool of Pharmacy, China Medical University, Taichung 40402, Taiwan, ROC; Department of Medical Research, China Medical University Hospital, Taichung 40402, Taiwan, ROC. Electronic address: hou5133@gmail.com.
Food chemistry.Food Chem.2012 Dec 15;135(4):2307-12. doi: 10.1016/j.foodchem.2012.07.061. Epub 2012 Jul 20.
Liquorice (root of Glycyrrhiza uralensis FISCH) is an ingredient of candies and used as a popular medicine in Europe and oriental countries. Cyclosporine (CsA), an immunosuppressant with narrow therapeutic window, is widely used in transplant patients. The absorption and disposition of CsA were asso
PMID 22980806

Japanese Journal

Species differences in toxicokinetic parameters of glycidol after a single dose of glycidol or glycidol linoleate in rats and monkeys

Wakabayashi Ken-ichi,Kurata Yoshimasa,Harada Tomoo [他],TAMAKI Yasushi,NISHIYAMA Naohiro,KASAMATSU Toshio
Journal of toxicological sciences 37(4), 691-698, 2012-08-01
NAID 10030502123

フグ類の体内におけるテトロドトキシンの動態に関する研究

長島裕二
日本水産學會誌 = Bulletin of the Japanese Society of Scientific Fisheries 78(3), 380-383, 2012-05-15
フグは強力な神経麻痺毒であるフグ毒テトロドトキシン(TTX)をもち,その主な毒化経路は海洋微生物によるTTX産生を出発点とするという食物連鎖説が有力視されている。給餌飼育実験から,フグでは経口的に摂取されたTTXは腸管で吸収され,血液による運搬を経て,肝臓など特定の組織に取り込まれ濃縮蓄積するという一連の体内動態が成立していることが推測される。これに対し,TTXを含む餌を与えて飼育してもTTXを蓄 …
NAID 10030312628