The goal of this observational study is to measure and compare the presence of microplastics in children with inflammatory bowel disease (IBD) and children without IBD. The main questions it aims to answer are: Are microplastics detectable in different biological samples from children? Are there differences in microplastic burden between children with and without IBD? Researchers will collect biological samples including: intestinal tissue (from routine endoscopy), stool, urine, blood. Raman spectroscopy will be used to detect and characterize microplastics in each sample type. Participants will not receive any medication or intervention as part of this study. All samples will be collected during standard clinical procedures.