Datasets used to support the work presented in: Beringer, C.J., K.W. Goyne, R.N. Lerch, E.B. Webb, and D. Mengel. 2020: Clothianidin decomposition in Missouri wetland soils. J. Environ. Qual. JEQ-2020-05-0167-TR

Neonicotinoid pesticides can persist in soils for extended time periods;
however, they also have a high potential to contaminate ground and surface
waters. Studies have reported negative effects associated with
neonicotinoids and non-target taxa, including aquatic invertebrates,
pollinating insect species, and insectivorous birds. This study evaluated
factors associated with clothianidin (1-[(2-chloro-1,3-thiazol-5-yl)
methyl]-3-methyl-2-nitroguanidine, CTN) degradation and sorption in
Missouri wetland soils to assess the potential for wetland soils to
mitigate potential environmental risks associated with neonicotinoids.
Solid-to-solution partition coefficients (Kd) for CTN sorption to eight
wetland soils were determined via single-point sorption experiments, and
sorption isotherm experiments were conducted using the two most
contrasting soils. Clothianidin degradation was determined under oxic and
anoxic conditions over 60 d. Degradation data were fit to zero- and
first-order kinetic decay models to determine CTN half-life, i.t0.5).
Sorption results indicated CTN sorption to wetland soil was relatively
weak (average Kd = 3.58 L kg-1); thus, CTN has the potential to be mobile
and bioavailable within wetland soils. However, incubation results showed
anoxic conditions significantly increased CTN degradation rates in wetland
soils (anoxic average t0.5 =27.2 d; oxic average t0.5 = 149.1 d). A
significant negative correlation was observed between anoxic half-life
values and soil organic carbon content (r2=0.782; p=0.046). Greater CTN
degradation rates in wetland soils under anoxic conditions suggest that
managing wetlands to facilitate anoxic conditions could mitigate CTN
presence in the environment and reduce exposure to non-target organisms.