The Right to a Healthy Environment in La Oroya v. Peru: A Landmark Judgement of the IACtHR

The Right to a Healthy Environment in La Oroya v. Peru: A Landmark Judgement of the IACtHR

[Patricio Trincado Vera is a Research Assistant at the Transboundary Legal Studies Department at Groningen University.]

March 2024 was a month with significant advances in the area of human rights and environmental protection on a regional level. The European Court of Human Rights has been at the centre of the debate with the three judgements on climate change and environmental issues that it released, being the Verein Klimaseniorinnen Schweiz v. Switzerland the most notable one due to the establishment of positive obligations with regards to climate change under Article 8 of the European Convention on Human Rights.

However, on the other side of the Atlantic ocean, another interesting judgement was released by the Inter-American Court of Human Rights: La Oroya v. Peru. La Oroya is a city of 33.000 inhabitants in the region of Sierra Central in Peru (para. 67). Since 1922, the metallurgical facility Complejo Metalúrgico de La Oroya has been operating in this city (para. 67). During this time, its metallurgical activities have affected 30.200 hectares of vegetation, as well as the air, soil and water in La Oroya, causing it to be one of the 10 more contaminated cities in the world (para. 76). Since at least the 70s, several reports have warned about the dangers and risks that the activities of the CMLO meant for the health of La Oroya’s population and environment, including the prevalence of respiratory diseases (para. 76-84). Out of the 80 alleged victims that filed the complaint for this case 2 of them lost their lives as a consequence of these health complications (para. 219). Because of this, the Court found the State of Peru responsible for the violation of the right to a healthy environment (RHE), the right to health, the right to personal integrity, the right to life, the right to access to information, the right to political participation, children’s rights, and the obligation of progressive development of article 26 (para. 266).

La Oroya v. Peru will have significant implications for the development of human rights in relation to environmental issues within the Inter-American System of Human Rights, particularly with regard to the RHE. The RHE was recognised as a justiciable and autonomous right protected under article 26 of the American Convention for the first time in the Advisory Opinion OC-23/17. Building on the contribution of this advisory opinion and the Lhaka Honhat v. Argentina case, La Oroya furthers the understanding of this right on several aspects. These contributions place the Inter-American Court at the forefront of the development of environmental human rights, and may have implications for future climate litigation, not only within the Inter-American sphere, but also in other human rights regimes. In this brief blog I will focus on two of the major contributions of La Oroya to the RHE.

Right to Breath Clean Air, Right to Water Free of Pollution and an Ecocentric Approach to the RHE

In La Oroya v. Peru, the Court further specified the content of the RHE by establishing that it encompasses two new rights as substantive elements: the right “to breathe air with pollution levels that do not pose a significant risk” to the enjoyment of human rights, and the the right “for water to be free from pollution levels” that pose a significant risk for the enjoyment of human rights (para. 120-121). Both these rights impose several obligations to Member States, such as the obligation to establish norms and public policies that define standards for the quality of air and water; to monitor the quality of the air and water and to inform the public about it; to create action plans to control the quality of the air and water; to identify the main sources of contamination; and to implement the standards of quality (para. 120-121). In the case of the right to water free of pollution, the State also must take actions to ensure that the administration of water resources is done in a sustainable manner (para. 121). The State must design measures in accordance with both the best scientific knowledge available and the criteria of availability, accessibility, sustainability, quality, adaptability, and international cooperation.

Most notably, the Court analysed these substantive aspects of the RHE by adopting an explicit ecocentric approach. This approach refers to “the encompassing idea that disrupts the human/nature divide and considers the relationship between organisms and the healthy interaction of all components of ecosystems, including human beings” (De Vido, 110). In other words, the ecocentric approach understands that Nature is a collective entity that includes human beings and that it is worthy of protection.

 This approach is better exemplified by the way in which the Court addressed the distinction of the right to water as a substantive aspect of the RHE and the right to water as an autonomous right in this case (La Oroya v. Peru, para.124).

The right to water as an autonomous right was recognised in the judgement of Lhaka Honhat v. Argentina. There, the Court stated that the right to water was protected under article 26 of the ACHR, and that it “entitles everyone to sufficient, safe, acceptable, physically accessible and affordable water for personal and domestic uses” (Lhaka Honhat v. Argentina, para. 222, 226). As such, the right to water as an autonomous right protects the use, access, and enjoyment of water for human use (La Oroya v. Peru, para. 124).

This right is not to be confused with the right to water free of pollution, which is one of the substantive aspects of the RHE (para. 124). As the Court stated in La Oroya, this aspect of the RHE protects the water basins as elements of the environment that have intrinsic value since they constitute a universal interest, and because of their importance for other living organisms, including human beings (para. 124).

In La Oroya, the Court stated that the right to water as an autonomous right is to be understood from an anthropocentric perspective, while the right to water as a substantive aspect of the RHE is to be understood from an ecocentric perspective (para. 124). This means that in order to find a violation of the right to water as an autonomous right, the affectation of the access to water must have an impact on human beings. This is not the case with the right to water as a substantive aspect of RHE, that only requires an affectation of water basins, even in the absence of certainty or evidence of the risk for human beings’ rights.

This ecocentric approach was applied by the Court when analysing the responsibility of Peru for violating the RHE in La Oroya. Indeed, the Court stated that the high levels of contamination of the air, water and soil had an impact on the different elements of the environment in the city of La Oroya in themselves (para. 179). While the health, life, and personal integrity of the inhabitants of La Oroya were also affected, these affectations were analysed in relation to the right to health, life, and personal integrity respectively (para 179, 188-234). Even though the Court did not explicitly say it, this development may strongly suggest the recognition of rights of nature within the Inter-American System of Human Rights.

RHE: A jus cogens Norm?

A major development of La Oroya is that the Court suggested in paragraph 129 that the RHE should have the status of a peremptory norm of general international law, i.e. a jus cogens norm (para. 129).

The Court stated that several States have recognised the RHE on several occasions, which entail an obligation of protection for the International community as a whole (para. 129). Because of the current climate crisis that threatens the survival of species, the International protection of the environment requires the progressive recognition of the prohibition of conducts that negatively affect the environment as a peremptory norm of general international law, a jus cogens norm (para. 129).

Furthermore, the Court referred to the importance of the “legal expressions of the International Community, whose superior universal value is indispensable to guarantee essential or fundamental values” (para. 129). Since the protection of “the interests of future and present generations”, as well as the conservation of the environment against its degradation, are fundamental for the survival of humanity, the Court suggests that the RHE should be considered as a jus cogens norm (para. 129).

In that sense, the Court did not state that the RHE has a jus cogens status, it simply said that it should have. The Court did not further elaborate on the implications of its statement, nor on what such a recognition would mean in practice.

In their separate opinion, judges Pérez Manrique, Ferrer Mac-Gregor Poisot, and Mudrovitsch, who argued in favour of considering the RHE as a jus cogens norm, delved into the consequences of this recognition. They stated that this would mean that any State would be able to demand from others the compliance of this norm (Separate Opinion of Judges Pérez, Ferrer, and Mudrovitsch, para. 96). The jus cogens status would also mean that articles 53 and 64 of the Vienna Convention on the Law of Treaties apply (para. 97-98). Consequently, States would not be able to subscribe treaty obligations that are contrary to the RHE, and that those that are already in force are annulled (para. 97-98). Thus, the recognition of the RHE as a jus cogens norm would mean a limitation on the sovereignty and the freedom of choice of states, and its effects would extend beyond the Inter-American System of Human Rights into International Law as a whole (para. 98).

Considering this separate opinion, it is clear that the current composition of the Court could not reach an agreement on the jus cogens status of the RHE. It remains to be seen whether the position of judges Pérez, Ferrer and Mudrovitsch will be the route that the Court decides to take in future case-law.


The developments mentioned here that makes La Oroya v. Peru a landmark case, are only some of the many aspects addressed by this judgement. All of them will undoubtedly have a lasting impact on human rights in relation to environmental matters.

The ecocentric approach taken by the Court in this case, as well as the discussion on the jus cogens status of the RHE, opens up the possibilities for future developments both within the Inter-American System and beyond it. More research and analysis of this judgement is needed to adequately understand all of the implications that will have for the Inter-American case-law and for international human rights law in general.

The future Advisory Opinion on the Climate Emergency and Human Rights requested by Chile and Colombia will be a very interesting opportunity for the Court to further expand the grounds laid by this judgement in relation to climate change.

Print Friendly, PDF & Email
Climate Change, Featured, General, Public International Law
No Comments

Sorry, the comment form is closed at this time.