119. The object and purpose of environmental law, as mentioned in Chapter 3, is precisely to protect the environment against harm that results in the degradation of the human habitat and, consequently, the degradation of an individual’s living conditions. To this end, international environmental law contains a series of norms and tools to implement the principle of prevention with regard to the environment, such as environmental impact assessments, environmental quality standards, and maximum permissible limits.69 120. In this context, several State obligations that are included in the body of norms of environmental law are relevant for compliance with State obligations in the area of human rights and promote their effectiveness – considering that the exercise and enjoyment of those rights depends, above all, on the habitat and physical environment of the human being (see Chapter 3). In the case of the construction of major infrastructure projects in the Caribbean Sea that could have a significant impact on the marine environment of this Region and, consequently, on the exercise and enjoyment of the basic rights of the inhabitants of its coasts and islands, the norms of international environmental law – which see, precisely, to prevent and to mitigate damage to the human habitat – play a crucial role in order to ensure the human rights of those potentially affected. 121. Despite the foregoing, to date, the Court has not had the occasion to establish whether, and to what extent, State obligations under international environmental law can be considered human rights obligations in light of the Pact, particularly as part of the obligations recognized in Articles 4(1) and 5(1) of this instrument; a question posed in this request for an advisory opinion. 122. This question does not seek to determine the existence of a formal legal relationship between environmental law and human rights, in the sense that a formal violation of environmental law would automatically be considered a violation of human rights. The presentation of this request for an advisory opinion seeks to determine the substantive normative interaction between environmental law and human rights in order to establish whether, and to what extent, international human rights law should be interpreted in light of, or in connection with, certain obligations established by international environmental law. 123. Two obligations established by international environmental law are absolutely essential for the real, full and effective guarantee of the rights and freedoms established in the Pact of San José and, consequently, they should be considered obligations that arise from that instrument. These obligations are: (a) the obligation to make complete environmental impact assessments not only of a national, but also of a transboundary nature, prior to the startup of any project that could cause a severe negative impact on the environment – assessments that should necessarily include the determination of the necessary and sufficient measures to prevent and to mitigate any possible 69 Marcos A. Orellana, Derechos Humanos y Ambiente: Desafios para el Sistema Interamericano de Derechos Humanos, Center for International Environmental Law (CIEL) 2007. Available at: www.ciel.org/Publications/Morellana_DDHH_Nov07.pdf, p. 296 60