Because it is the outermost layer of the plant, epicuticular
wax (which is also part of the plant's lipid fraction) is of special importance in accumulating organic air pollutants. Compounds can directly move from the gas phase into the wax layer of plants and particle-bound xenobiotics can accumulate in the epicuticular
wax. Well-structured wax crystals can incorporate more dust than eroded, amorphous wax-plates, indicating that wax chemistry and structure may largely determine and modify the uptake of POPs.
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