THAI LAW ON THE MITIGATION OF RISKS FROM FINE PARTICULATE MATTER PM 2.5

Abstract

Fine particulate matter with an aerodynamic diameter of not more than 2.5 micrometers (PM 2.5) is a form of air pollution that poses severe risks to human health and is internationally recognized as a major risk factor for premature mortality. Thailand has experienced persistent PM2.5 pollution since 2019, resulting in significant adverse impacts on quality of life, public health, and socio-economic development. Although several laws exist to regulate air pollution, the problem has persisted and shows an increasing tendency, reflecting structural limitations within the Thai legal system. This study aims to examine Thai laws relevant to the reduction of risks arising from PM2.5 pollution by analyzing applicable legal principles, statutory provisions, the evolution of relevant laws, the current legal framework, as well as practical problems and obstacles in law enforcement. The findings reveal that the relevant Thai legal principles include the duty of the State, the precautionary principle, the polluter pays principle, integrated environmental management, public participation, and the right to health. However, these principles are dispersed across multiple statutes, lack systematic integration, and fail to generate coherent and enforceable legal obligations. Structural analysis further indicates that the Thai legal system is characterized by a “state duty centered legal structure” rather than a rights-based framework. As a result, the management of PM2.5 pollution largely depends on administrative discretion, thereby limiting the roles of the public and the judiciary in holding the State accountable. When compared with international standards particularly the health-based air quality management approach advocated by the World Health Organization this study argues that Thailand should enact a comprehensive clean air law or reform existing legislation in order to enhance the effective and sustainable protection of public health and the environment.