Formalin (Formaldehyde) available at Bio Shop™ is a strong preservative and disinfectant used in very low concentrations for specific industrial and cosmetic applications. Commonly used in professional hair straightening treatments (Brazilian/Keratin) and as a powerful preservative in formulations that require strong microbial control. Due to its potency and potential health risks, it must be handled with extreme care, protective gear, and proper ventilation. Use only up to 0.2% in cosmetics as per safety guidelines. Not recommended for DIY or leave-on skincare. Always follow legal and safety usage protocols when formulating with this chemical.