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This study evaluated the extent to which hazardous or contaminating chemical substances in building materials recovered from renovation and demolition activities limit their reuse and recycling potential within a circular economy framework. Four material categories were examined: concrete, timber, steel and PVC based products, selected based on their significant presence in construction related waste streams and their established pathway for circular use. These material categories were examined on their chemical acceptability and technical suitability. A quantitative research methodology was adopted using secondary data from peer-reviewed scientific studies that reported measured contaminant concentration and material properties. The concentration reported for recovered concrete, timber and steel-related electric arc furnace dust were compared with the Swedish Environmental Protection Agency guideline values for sensitive land use and less sensitive land use, while restricted phthalates in PVC based products were compared with the applicable EU REACH Annex XVII limit. The result showed that contamination patterns differed considerably between material categories. Heavy metal concentrations in recovered concrete were generally below the comparative guideline values, whereas some concrete fractions, particularly those exposed to tar or bituminous materials, contained polycyclic aromatic hydrocarbons (PAH) above both guideline levels. Recovered timber showed substantial variation between average and maximum contaminant concentration with preservative treated and surface treated wood contributing to elevated levels of several hazardous substances. Steel maintained strong circular potential when recovered intact, but remelting through electric arc furnace (EAF) generates EAF dust containing heavy metals at concentrations exceeding both KM and MKM thresholds. Some recovered PVC products contained restricted legacy phthalates above the REACH limit. The material properties analysis further showed that chemical contamination did not always cause direct deterioration of technical performance, as some treated or chemically modified materials retained acceptable or improved selected properties. The study concluded that chemical contamination represented a conditional rather than an absolute barrier to circular use. Safe circularity required contamination assessment, knowledge of material history, effective sorting, targeted chemical testing and consideration of both chemical acceptability and technical performance when selecting reuse, recycling, treatment or disposal pathways.