The textile industry's business model is currently unsustainable and systemic changes must be made. The transition to a circular textile economy can be a major lever for this. However, it faces multiple issues, including the (in)ability of current legislations to provide sufficient protection regarding hazardous chemicals in recirculating materials. It is therefore crucial to identify legislative gaps that prevent the implementation of a safe circular textile economy, and to identify which chemicals could jeopardize this process. With this study, we aim to identify hazardous substances that could be found in recirculated textiles, to identify and discuss gaps in current regulations covering chemicals in textiles, and to suggest solutions to ensure better safety of circular textiles. We compile and analyze data on 715 chemicals and their associated functions, textile production stage, and hazard data. We also present how chemicals have been regulated over time and discuss regulations' strengths and weaknesses in the perspective of circular economy. We finally discuss the recently proposed Ecodesign regulation, and which key point should be included in the future delegated acts. We found that most of the compiled chemicals present at least one recognized or suspected hazard. Among them, there were 228 CMR (carcinogenic, mutagenic, reprotoxic substances), 25 endocrine disruptors, 322 skin allergens or sensitizers, and 51 respiratory allergens or sensitizers. 30 chemicals completely or partially lack hazard data. 41 chemicals were found to present a risk for consumers, among which 15 recognized or suspected CMR and 36 recognized or suspected allergens/sensitizers. Following the analysis of regulations, we argue that an improved risk assessment of chemicals should consider chemicals specific hazardous properties and product's multiple life cycles, instead of being limited to the product's end-of-life stage. We especially argue that implementing a safe circular textile economy requires that chemicals of concern are eliminated from the market.