BACKGROUND: There is a continuous need to advance pesticide plant uptake models in support of improving pest control and reducing human exposure to pesticide residues. The periderm of harvested root and tuber crops may affect pesticide uptake, but is usually not considered in plant uptake models. To quantify the influence of the periderm on pesticide uptake from soil into potatoes, we propose a model that includes an explicit periderm compartment in the soil–plant mass balance for pesticides. RESULTS: Our model shows that the potato periderm acts as an active barrier to the uptake of lipophilic pesticides with high KOW, while it lets more lipophobic pesticides accumulate in the medulla (pulp). We estimated bioconcentration factors (BCFs) for over 700 pesticides and proposed parameterizations for including the effects of the periderm into a full plant uptake modeling framework. A sensitivity analysis shows that both the degradation half-life inside the tuber and the lipophilicity drive the contributions of other aspects to the variability of BCFs, while highlighting distinct dynamics in the periderm and medulla compartments. Finally, we compare model estimates with measured data, showing that predictions agree with field observations for current-use pesticides and some legacy pesticides frequently found in potatoes. CONCLUSION: Considering the periderm improves the accuracy of quantifying pesticide uptake and bioconcentration in potatoes as input for optimizing pest control and minimizing human exposure to pesticide residues in edible crops.
Bibliographical noteFunding Information:
This work was financially supported by the Sun Yat‐sen University (grants 58000–18841211 and 58000‐18841290), as well as by the SPRINT project (grant agreement no. 862568) and by the FNS‐Cloud project (grant agreement no. 863059), both funded under the European Unionʼs Horizon 2020 Research and Innovation program.
© 2021 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
- environmental modeling
- food crops
- food safety
- health risk assessment