Degrading plant materials play an important role in absorbing organic pollutants in soil, according to a study by researchers in the US and Israel.

Waxy plant biopolymers can absorb organic pollutants such as naphthol and phenanthrene. Whether these biopolymers degrade to form a useful part of soil humus when a plant dies has been open to question. They may release contaminants or continue to absorb them from the soil, which will have environmental consequences. Carbon-¹³ NMR spectroscopy and differential scanning calorimetry of two biopolymers, cutan and cutin, suggest that absorption is affected by decomposition.

With degradation, cutin loses its sorbent properties, while cutan remains a highly efficient sorbent of organic compounds.

• Cutin and Cutan Biopolymers: Their Role as Natural Sorbents
  M. Shechter, B. Xing, B. Chefetz,
  Soil Sci. Soc. Am. J. 2010, 74, 1139 – 1146.
  DOI: 10.2136/sssaj2009.0313