In this PhD I will study the fate and effects of fertilizer coating microplastics (MP) in soil. These microplastic coatings are used to control the rate of nutrient release to the soil. Important research questions are: (1) to what extent does the fertilizer coating MP accumulate in soil as compared to background levels of MP and (2) whether these MP may cause eco(toxico)logical effects for selected soil organisms and how these effects are related to polymer properties. To answer these research questions we will develop a robust method for analysis of MP in soils using advanced IR microscopic techniques and design and perform controlled laboratory experiments to investigate processes that control the fate and effects of MP in a variety of soil types and investigate samples from an already established field trial with 6 years additions of coated fertilizers.