This chapter examines how steganography can enhance security in cloud-based environmental pollution monitoring systems using IoT sensors. It covers various steganographic methods for different media and their potential use in protecting environmental data. The study explores advanced techniques like DNA-based and deep learning approaches, particularly in cloud settings. The research addresses challenges and ethical issues, including legal and privacy concerns, associated with applying steganography to environmental monitoring. It presents case studies on air and water quality monitoring to illustrate the practical benefits and limitations of integrating these technologies. The review concludes by looking at emerging trends such as quantum steganography and AI-driven methods, stressing the need to balance data security with transparency in environmental research.