Pollution of the aquatic environment by plasticizers leached from microplastics originating from linear sewage systems

The study investigates the emission of plasticizers into the aquatic environment from sewer systems, such as sewer pipes and their components. To analyze the influence of time and temperature on the migration of phthalates, two methods were used: multiple regression and Helwig’s information capacity indices. At the highest temperature analyzed of 18 °C, the emission levels from the sewer pipe were as follows: DEP ranged from 0.0036 to 0.0155 mg/kg, DBP ranged from 0.0972 to 0.2525 mg/kg, and DEHP ranged from 0.0023 to 0.0072 mg/kg. For the gasket, the emission levels of four phthalates were noted: DBP ranged from 0.028 to 0.042 mg/kg, DEHP ranged from 0.022 to 0.067 mg/kg, DBP ranged from 0.09 to 0.26 mg/kg, and DMP ranged from 0.029 to 0.053 mg/kg. The research confirmed that, depending on environmental conditions, phthalate esters are leached from microplastics originating from these systems. Depending on the analyzed material and type of plasticizer, various parameters had varying impacts on the extent of their emission. Higher temperatures increased the migration of substances from the polymer matrix, while lower temperatures slowed down this process.