To ensure market entry and consumer safety, products must comply with OEKO-TEX Standard 100, which guarantees the absence of harmful substances. For the US market, ensure compliance with CPSIA (especially for youth sizes), and for the EU, adhere to REACH regulations. If the jerseys are marketed as 'eco-friendly,' verify the Global Recycled Standard (GRS) certification. Crucially, for 'Brand' jerseys, you must verify the Authorization Letter (LOA) from the trademark holder to avoid customs seizure due to IP infringement.