Plant uptake of xenobiotic
compounds is crucial for phytoremediation
(including green stormwater infrastructure) and exposure potential
during crop irrigation with recycled water. Experimentally determining
the plant uptake for every relevant chemical is impractical; therefore,
illuminating the role of specific functional groups on the uptake
of trace organic contaminants is needed to enhance predictive power.
We used benzimidazole derivatives to probe the impact of functional
group electrostatic properties and position on plant uptake and metabolism
using the hydroponic model plantArabidopsis thaliana. The greatest plant uptake rates occurred with an electron-withdrawing
functional group at the 2 position; however, uptake was still observed
with an electron-donating group. An electron-donating group at the
1 position significantly slowed uptake for both benzimidazole- and
benzotriazole-based molecules used in this study, indicating possible
steric effects. For unsubstituted benzimidazole and benzotriazole
structures, the additional heterocyclic nitrogen in benzotriazole
increased plant uptake rates compared to benzimidazole. Analysis of
quantitative structure–activity relationship parameters for
the studied compounds implicates energy-related molecular descriptors
as uptake drivers. Despite significantly varied uptake rates, compounds
with different functional groups yielded shared metabolites, including
an impact on endogenous glutathione production. Although the topic
is complex and influenced by multiple factors in the field, this study
provides insights into the impact of functional groups on plant uptake,
with implications for environmental fate and consumer exposure.