Community of La Oroya Wins Landmark Court Decision

Metal smelter in La Oroya. PHOTO:Dr. Meche Lu

In March, the Inter-American Court of Human Rights issued a landmark ruling in the case of La Oroya v. Peru. The Court ruled that the State of Peru has violated numerous human rights of the inhabitants of La Oroya, including the rights to a healthy environment, health, personal integrity, a dignified life, access to information, and political participation. This decision will add to the pressure to force Peru to compensate the community for damages and ensure justice is done.

La Oroya, a city high in the Andes, has been considered one of the most polluted places on earth. A metal smelting complex that has operated in La Oroya for generations without adequate pollution controls has caused environmental and public health calamities.

ELAW Scientist Dr. Meche Lu has been supporting the community of La Oroya and the lead organization that brought the case, the Interamerican Association for Environmental Defense (AIDA), as they have fought for a clean and healthy environment in La Oroya.

For decades, Meche has been a key advisor to the group of organizations that collaborated to document the harm in La Oroya, bring national and international attention to the issue, and eventually litigate the case. Along the way, Meche collaborated with the Movimiento por la Salud de La Oroya (Movement for the Health of La Oroya, MOSAO) to sample soil and dust in La Oroya. She participated in numerous community workshops and meetings of MOSAO, eventually presenting scientific evidence at the Peruvian Congress. Finally, in 2021 when the case was to be heard before the Inter-American Court in Uruguay, she submitted written testimony. In the judgment, the Court explains:

“For her part, witness María Mercedes Lu De Lama pointed out that the group most at risk of exposure to lead were girls and boys since their main activities were carried out in parks and outdoors. In particular, she pointed out that in La Oroya, ‘the schoolyards, preschool centers, soccer fields, parks, and other areas are paved.’ The witness explained that fresh lead carried by particles in the air accumulates in these paved areas, and hence boys and girls are more exposed to ingesting them when putting their hands to their mouth or face…Logically, the more lead there is in the air, the greater the risk of ingesting it for children.” 

Smelter in La Oroya and rooftops of an elementary school. PHOTO: Dr. Meche Lu
Smelter in La Oroya and rooftops of an elementary school. PHOTO: Dr. Meche Lu

Several studies have demonstrated high levels of lead, arsenic, cadmium, and other hazardous pollutants in the air, water, and soil in La Oroya. ELAW’s dust-wipe study from 2002 found that 100% of the 22 samples collected from paved surfaces of sidewalks, paved parks, pre-schools, and elementary schools where children play, ranged from 610 to 5,202 micrograms per square foot, exceeding the U.S. standard at that time of 40 micrograms per square foot. In 1999, Peru’s health authority reported an average of blood lead levels in children under 10 years old at 10 times the current U.S. Center for Disease Control (CDC) reference value. No safe blood lead levels have been identified by the CDC. Even low doses of lead can affect all organ systems, causing permanent adverse health impacts, particularly in children’s brains and nervous systems. These negative effects could be exacerbated by the presence of arsenic, cadmium, and other pollutants as demonstrated in several studies in La Oroya. 

David Boyd, United Nations Special Rapporteur on Human Rights and the Environment says: “The Inter-American Court’s decision is the strongest and most comprehensive judgment of any regional human rights court to date. Not only does it provide long overdue environmental justice for the people of La Oroya in Peru, it also establishes a vital precedent that will be used by concerned citizens, communities, courts, and environmental human rights defenders all over the world.”

The Court ordered the State of Peru to take reparation measures, including:

  • A baseline diagnosis must be carried out to determine the state of air, water, and soil contamination in La Oroya, which must include a plan for remediation of environmental damage;
  • Free medical care must be provided to victims of violations of their rights to health, life, and personal integrity;
  • Regulations that define air quality standards must be made compatible so that the maximum permissible values in the air for lead, sulfur dioxide, cadmium, arsenic, particulate matter, and mercury do not exceed the maximum values necessary for the protection of the environment and people’s health;
  • The effectiveness of the alert system in La Oroya must be guaranteed, and a monitoring system for air, soil, and water quality be developed;
  • The inhabitants of La Oroya who suffer from symptoms and diseases related to exposure to contaminants resulting from mining-metallurgy activity must have specialized medical care through public institutions; and
  • Monetary sums must be paid for material and non-material damage established in the judgment.

“This has been a long road and has taken an immense joint effort of many people, especially the local leaders, and colleagues at AIDA to secure this trailblazing victory,” says Meche. “We are all so happy with the decision!”

ELAW and the other organizations and individuals who have fought for justice for La Oroya will be monitoring Peru’s compliance and looking out for a brighter future for the community.

To learn more, please check out the resources below.

Bern Johnson
Executive Director
Environmental Law Alliance Worldwide


David Boyd, UN Special Rapporteur on Human Rights and the Environment, analyzes the case: Landmark Court Decision on Right to a Healthy Environment: La Oroya v. Peru

AIDA, March 22, 2024

Inter-American Court ruling on La Oroya case sets key precedent for the protection of a healthy environment

Inter-American Court of Human Rights
Official Summary of the Judgment
Full Text of the Judgment

Photo 1: Metal smelter in La Oroya. PHOTO: Dr. Meche Lu