This is a supplementary dataset to the paper: Vaněk A., Đorđević T., Mihaljevič M., Vaňková M., Fizková K., Zádorová T., Vokurková P., Galušková I., Penížek V., Drábek O., Tasev G., Serafimovski T., Boev I., Boev B. (2024): Thallium in Technosols from Allchar (North Macedonia): Isotopic and speciation insights. Environmental Pollution 357, 124413. DOI: 10.1016/j.envpol.2024.124413 This research was supported by the Johannes Amos Comenius Programme (OP JAC), project No. CZ.02.01.01/00/22_008/0004605, Natural and anthropogenic georisks. The dataset is published under the Creative Commons Attribution 4.0 International License (CC-BY-4.0). This license allows others to distribute, remix, adapt, and build upon the dataset for any purpose, even commercially, as long as they give appropriate credit to the original creator(s).