Thanks for your suggestion. We have introduced the sampling sites and added the following information: “The e-waste dismantling area we studied is an E-Waste Recycling Town located in South China, where the possible human body burden and health consequences of heavy metals exposure have been reported [30].” Huang, W.L. International Journal of Environmental Research and Public Health, 2021, 18(23):12428. https://doi.org/10.3390/ijerph182312428 Point 3.
The digested product was diluted to 30 ml with ultrapure water and then stored at 4°C.