## 2 Materials and Methods
### Human Health Risk Assessment Method  
The potential non-carcinogenic health risks for both adults and children were assessed using the commonly accepted methodologies outlined by the U.S. Environmental Protection Agency (USEPA) [33]. The human health risk assessment considered the exposure pathway of pesticide ingestion through contaminated soil. The non-dietary chronic daily intake  
Figure 1: Overview maps of the study area. **(a)** A geographical map of Siping City showing the location of Jilin Province, China; **(b)** a map of Siping City showing the location of the study area; **(c)** the distribution map of the study area. (CDI\({}_{\rm{intake}}\)) of pesticides (mg kg\({}^{-1}\) day\({}^{-1}\)) resulting from incidental soil ingestion by adults and children was estimated using the following equations [34,35]. \[{\rm{CDI}}_{\rm{intake}}=({\rm{C_{s}}}\times{\rm{EF}}\times{\rm{ED}}\times{\rm{ IR_{i}}}\,/\,{\rm{AT}}\times{\rm{BW}})\times{\rm{CF}} \tag{1}\]  
where \({\rm{C_{s}}}\) (mg/kg) is the concentration of pesticide residue in the soil, EF is the exposure frequency (days/year), ED is the exposure duration (years), IR\({}_{i}\) is the rate of contaminated soil ingestion (mg/day), AT is the average lifetime (days), BW is the average body weight (kg), and CF is the conversion factor (kg mg\({}^{-1}\)). \[{\rm{CDI}}_{\rm{dermal}}=({\rm{C_{s}}}\times{\rm{DA}}\times{\rm{DAF}}\times{ \rm{AF}}\times{\rm{EF}}\times{\rm{ED}}\,/\,{\rm{AT}}\times{\rm{BW}})\times{\rm{CF}} \tag{2}\]  
where CDI\({}_{\rm{dermal}}\) is the estimated non-dietary CDI (mg/kg/day) of pesticide-contaminated soil particles via dermal contact, DA is the exposed dermal area (cm\({}^{2}\) day\({}^{-1}\)), DAF is the dermal adherence factor (mg cm\({}^{-2}\)) for soil, and AF (dimensionless) is the dermal absorption factor. \[{\rm{CDI}}_{\rm{inhalation}}={\rm{C_{s}}}\times{\rm{EF}}\times{\rm{ED}}\times{ \rm{IR_{i}}}/{\rm{PEF}}\times{\rm{AT}}\times{\rm{BW}} \tag{3}\]  
where CDI\({}_{\rm{inhalation}}\) is the estimated non-dietary CDI (mg/kg/day) of pesticide-contaminated soil particles via the inhalation pathway, IR\({}_{\rm{in}}\) is the rate of inhalation (m\({}^{3}\)/day), and PEF is the particle emission factor (m\({}^{3}\)/kg). The non-cancer risk of pesticides is expressed as a hazard quotient (HQ), whereas the hazard index (HI) is the sum of HQ of individual pesticides, which was calculated following the equation [36,37,38]. \[{\rm{HQ}}={\rm{CDI}}/{\rm{RfD}} \tag{4}\]  
\[{\rm{HI}}=\sum{\rm{HQ}}_{\rm{Presticide}} \tag{5}\]  
where RfD is the reference dose (mg/kg/day) of a pesticide. The maximum acceptable reference doses (RfDs) in humans for atrazine, acetochlor, alachlor, nicosulfuron, and mesotrione considered are 0.10, 0.02, 0.002, 1.25, and 0.007 mg/kg/day [39,40,41,42,43]. In this study, the ingestion rate (IR\({}_{i}\)) for both human adults and children was set at 100 mg/day, and the inhalation rate (IR\({}_{\rm{inh}}\)) for both groups was established at 17.50 m\({}^{3}\)/day. The body weight (BW) was determined to be 62 kg for adults and 12 kg for children. The averaging lifetime (AT) for both populations was considered to be 70 years (equivalent to 25,550 days). The exposure frequency (EF) for both human adults and children was standardized at 350 days/year. Regarding exposure duration (ED), it was set at 30 years for adults and 3 years for children. The exposed dermal area (DA) was estimated at 5700 cm\({}^{2}\)/day for adults and 1050 cm\({}^{2}\)/day for children. The dermal adherence factor (DAF) was assigned values of 0.07 mg/cm\({}^{2}\) for adults and 0.20 mg/cm\({}^{2}\) for children. Both groups shared a common dermal absorption factor (AF) of 0.13. Additionally, the particle emission factor (PEF) for both adults and children was fixed at 1.36 \(\times\) 10\({}^{9}\) m\({}^{3}\)/kg, and the conversion factor (CF) was uniformly taken as 1 \(\times\) 10\({}^{-6}\) kg/mg across both populations.