Assessment of soil pollution by petroleum products in cities of Karaganda region Natalya Tsoy, Yelena Tseshkovskaya, Aigul Oralova, Alma Akhmetova and Natalya Serykh E3S Web Conf., 555 (2024) 01016 Published online: 30 July 2024 DOI: 10.1051/e3sconf/202455501016