R code for: Following regulation, imidacloprid persists and flupyradifurone increases in non-target wildlife

After regulation of pesticides, determination of their persistence in the
environment is an important indicator of effectiveness of these measures.
We quantified concentrations of two types of systemic insecticides:
neonicotinoids (imidacloprid, acetamiprid, clothianidin, thiacloprid, and
thiamethoxam) and butenolides (flupyradifurone), in off-crop non-target
media of hummingbird cloacal fluid, honey bee (Apis mellifera) nectar and
honey, and wildflowers before and after regulation of imidacloprid on
highbush blueberries in Canada in April 2021. We found that mean total
pesticide load increased in hummingbird cloacal fluid, nectar, and flower
samples following imidacloprid regulation. On average, we did not find
evidence of a decrease in imidacloprid concentrations after regulation.
However, there were some decreases, some increases and other cases with no
changes in imidacloprid levels depending on the specific media, time point
of sampling and site type. At the same time, we found an overall increase
in flupyradifurone, acetamiprid, thiamethoxam and thiacloprid, but no
change in clothianidin concentrations. In particular, flupyradifurone
concentrations observed in biota sampled near to agricultural areas
increased by 2-fold in honey bee nectar, 7-fold in hummingbird cloacal
fluid, and 8-fold in flowers after the 2021 imidacloprid regulation. The
highest residue detected in this study was flupyradifurone at 665 ng/mL
(PPB) in honey bee nectar. Mean total pesticide loads were highest in
honey samples (84 ± 10 PPB) followed by nectar (56 ± 7 PPB), then
hummingbird cloacal fluid (1.8 ± 0.5 PPB), and least, flowers (0.51 ± 0.06
PPB). Our results highlight that limited regulation of imidacloprid does
not immediately reduce residue concentrations while other systemic
insecticides, possibly replacement compounds, concurrently increase in
wildlife.