fettlöslich

Fettlöslich is a German term that translates to "fat-soluble" in English. It describes substances that dissolve in fats, oils, or lipids. This property is crucial in various biological and chemical contexts. In biology, fat-soluble vitamins, such as vitamins A, D, E, and K, are absorbed by the body along with dietary fats and are stored in the body's fatty tissues and liver. This means they can accumulate in the body, and excessive intake can lead to toxicity. Conversely, water-soluble vitamins are easily excreted by the body.

In chemistry, the term fettlöslich refers to the solubility of a compound in non-polar solvents, which include fats and oils. This is in contrast to water-soluble substances, which dissolve in polar solvents like water. The concept of fettlöslichkeit (fat solubility) is often quantified by the partition coefficient, which measures the ratio of a solute's concentration in a lipid phase to its concentration in an aqueous phase. A high partition coefficient indicates that a substance is more fettlöslich.

The fettlöslich nature of certain compounds has implications for their environmental persistence and biological effects. For instance, fettlöslich pollutants like PCBs and DDT can accumulate in the fatty tissues of organisms and biomagnify up the food chain, posing ecological risks. Understanding fettlöslichkeit is therefore important for drug development, toxicology, environmental science, and nutritional studies.