CRC/C/GC/26 effects of environmental contaminants may even persist in future generations. States should consistently and explicitly consider the impact of exposure to toxic substances and pollution in early life. 25. States should recognize each stage of childhood, the importance of each stage for subsequent stages of maturation and development and children’s varying needs at each stage. To create an optimal environment for the right to development, States should explicitly and consistently consider all factors required for children of all different ages to survive, develop and thrive to their fullest potential and design and implement evidence-based interventions that address a wide range of environmental determinants during the life course. D. Right to be heard (art. 12) 26. Children identify environmental issues as being highly important to their lives. Children’s voices are a powerful global force for environmental protection, and their views add relevant perspectives and experience with respect to decision-making on environmental matters at all levels. Even from an early age, children can enhance the quality of environmental solutions, for example, by providing invaluable insights into issues such as the effectiveness of early warning systems for environmental hazards. Children’s views should be proactively sought and given due weight in the design and implementation of measures aimed at addressing the significant and long-term environmental challenges that are fundamentally shaping their lives. Creative means of expression, such as art and music, may be used by children to participate and express their views. Additional support and special strategies may be required to empower children in disadvantaged situations, such as children with disabilities, children belonging to minority groups and children living in vulnerable areas, to exercise their right to be heard. The digital environment and tools can enhance consultations with children and expand their capacity and opportunities to be effectively engaged in environmental matters, including through collective advocacy, if carefully used, with due attention given to challenges regarding digital inclusion.8 27. States must ensure that age-appropriate, safe and accessible mechanisms are in place for children’s views to be heard regularly and at all stages of environmental decision-making processes for legislation, policies, regulations, projects and activities that may affect them, at the local, national and international levels. For free, active, meaningful and effective participation, children should be provided with environmental and human rights education, age-appropriate and accessible information, adequate time and resources and a supportive and enabling environment. They should receive information about the outcomes of environment-related consultations and feedback on how their views were taken into account and have access to child-sensitive complaint procedures and remedies when their right to be heard in the environmental context is disregarded. 28. At the international level, States, intergovernmental organizations and international non-governmental organizations should facilitate the involvement of children’s associations and child-led organizations or groups in environmental decision-making processes. States should ensure that their obligations concerning children’s right to be heard are incorporated into international environmental decision-making processes, including in negotiations and the implementation of instruments of international environmental law. Efforts to enhance youth participation in environmental decision-making processes should be inclusive of children. E. Freedom of expression, association and peaceful assembly (arts. 13 and 15) 29. Children across the world are taking action, individually and collectively, to protect the environment, including by highlighting the consequences of climate change. States shall respect and protect children’s rights to freedom of expression, association and peaceful 8 GE.23-11144 General comment No. 25 (2021) on children’s rights in relation to the digital environment, paras. 16 and 18. 5