biokumulacj

Biokumulacja, or bioaccumulation, is the process by which chemical substances accumulate in an organism from all exposure routes, at a rate faster than they are eliminated, leading to internal concentrations higher than those in the surrounding environment. This can involve uptake from water, sediment, food, and air, with persistent and lipophilic compounds tending to accumulate in fatty tissues or organs such as the liver.

The rate and extent of biokumulacja depend on chemical properties (for example, persistence, hydrophobicity, and molecular size), organism traits (metabolic capacity, growth rate, diet), and environmental conditions. Substances that resist degradation and are not readily excreted are more likely to build up over time. Biokumulacja often intersects with biomagnifikacja, the increase in concentration of a substance as it moves up a food chain, particularly for persistent organic pollutants.

Biokoncentracja and biomagnifikacja are related concepts used to describe different exposure pathways and transfer dynamics. Biokoncentracja (bioconcentration) refers to uptake directly from the ambient medium, typically water, through interfaces such as gills or skin. Biomagnifikacja refers to the magnification of a substance’s concentration at each successive trophic level.

Measurement of biokumulacja commonly uses the bioconcentration factor (BCF) and the bioaccumulation factor (BAF), expressed as ratios of substance concentration in an organism to that in the environment. Values greater than one indicate accumulation. Examples of substances of concern include metals like mercury and cadmium, and persistent organic pollutants such as PCBs and DDT.