Dermody, Christopher Lee (2018-12). Uptake and Translocation of Polycyclic Aromatic Hydrocarbons by Plants in Soils. Master's Thesis. Thesis uri icon

abstract

  • Polyaromatic hydrocarbons (PAHs) and their interaction with plants have received an abundance of attention from the scientific community, as they are ubiquitous and recalcitrant in the environment. As some PAHs are known carcinogens, understanding how these pollutants bio-accumulate and become available for human consumption is imperative for pollution and exposure prevention. Many of the contaminant pathways associated with PAHs are well understood yet some disagreement exists in the published literature regarding the potential for PAHs to be taken up by plant roots to be subsequently translocated to above ground tissues. In this thesis, the mobility of PAHs within plant tissues is investigated to assess the significance of this bioaccumulation pathway. Physiochemical parameters, modeling studies, as well as research spanning several decades are reviewed. After examining all of the information in this thesis, it can be concluded that the translocation of PAHs from plant roots to above ground tissues is highly unlikely. Taking into account both, factors related to the physiochemical limitations associated with PAHs that restrict their intracellular and overall plant and impacts of lipophilic soil-contained components the soil-to-root-to-vegetation bioaccumulation pathway is generally not significant when assessing the risks related to exposure to PAHs through the consumption of crops grown on contaminated soils. Rather, the air-to-leaf (i.e. atmospheric deposition) and soil-to-air-to-leaf (re-volatilization) pathways dominate the contamination of terrestrial vegetation.
  • Polyaromatic hydrocarbons (PAHs) and their interaction with plants have received an abundance of attention from the scientific community, as they are ubiquitous and recalcitrant in the environment. As some PAHs are known carcinogens, understanding how these pollutants bio-accumulate and become available for human consumption is imperative for pollution and exposure prevention. Many of the contaminant pathways associated with PAHs are well understood yet some disagreement exists in the published literature regarding the potential for PAHs to be taken up by plant roots to be subsequently translocated to above ground tissues.
    In this thesis, the mobility of PAHs within plant tissues is investigated to assess the significance of this bioaccumulation pathway. Physiochemical parameters, modeling studies, as well as research spanning several decades are reviewed. After examining all of the information in this thesis, it can be concluded that the translocation of PAHs from plant roots to above ground tissues is highly unlikely. Taking into account both, factors related to the physiochemical limitations associated with PAHs that restrict their intracellular and overall plant and impacts of lipophilic soil-contained components the soil-to-root-to-vegetation bioaccumulation pathway is generally not significant when assessing the risks related to exposure to PAHs through the consumption of crops grown on contaminated soils. Rather, the air-to-leaf (i.e. atmospheric deposition) and soil-to-air-to-leaf (re-volatilization) pathways dominate the contamination of terrestrial vegetation.

publication date

  • December 2018