In the past, looging and oil exploration led to violent and disastrous contact with isolated Indians. In the early 1980s, exploration by Shell led to contact with the isolated Nahua tribe. Within a few years around 50% of the Nahua had died.This was in connection with the Camisea gas exploitation.

The Nahua is Nanti is an Amazonian indigenous group of nearly 500 inhabitants which live in the State of Kugapakori in Perúin the Nahua Nanti Kugapakori Territorial Reserve (RTKNN). Nahua Nanti had their first contact with Western populations in 1984 with a group of loggers which lead to a severe contagious of infectious and respiratory diseases decreasing the Nahua Nanti population up to 50% during the first year after the first contact with Western societies [1].   Initially, the Nahua lived in isolation, devoted to hunting, fishing, and wood gathering, individually or in small tribes. Currently, they live in the town of Santa Rosa de Serjali. In addition to subsistence activities, they occasionally engage in logging, sometimes exploited by illegal loggers or by their initiative, intending to get an income for subsistence [12].  

Between November 2014 and October 2015, the Occupational and Environmental Health Center (CENSOPAS), on behalf of the Ministry of Health (MINSA), collected urine samples among the Nahua of the RTKNN. Striking findings on high concentrations of mercury and other heavy metals, especially in children under 12 years of age attired the attention of medical authorities and led to more investigations on the Nahua’s health and the possible sources of contaminations [7].

The leaked report, titled Análisis de Situación de Salud del Pueblo Nahua de Santa Rosa de Serjali en la Reserva Territorial Kugapakori Nahua Nanti y Otros, states that government health authorities were first alerted to the mercury crisis among the Nahua when a six-month-old baby, initially diagnosed with pneumonia and his mother were admitted to a private clinic in Lima in November 2014 [5]. The baby was found to have severe anaemia, and his blood was tested for heavy metals, resulting in both him and his mother being diagnosed with “mercury intoxication.”[7].  According to the National Center for Epidemiology, Prevention and Control of Diseases (Ministry of Health) "Exposure to mercury may be due to natural reasons, contamination of food resources or occupational reasons" [1].  It could come from artisanal gold mining. There is no clarity on the primary source of contamination but scientists have pointed out on the Camisea Gas exploitation project run by Pluspetrol in the Urubamba Valley (see the related case on the EJAtlas) as one cause of environmental pollution. The Camisea Consortium currently operates in Block Lot 88 inside the indigenous reserve. Block Lot 88 was established in the 1980s, before the reserve was created, on February 14, 1990. The company has pre-established rights, but the Nahua and other peoples also defend their right to protection and self-determination. Camisea Project representatives have denied the possibility of being the cause of mercury pandemic among the indigenous Nahua Nanti. Surrounded mining projects using toxic substances is possibly another source of contamination [4].

In December 2018 the Nahua Nanti Indigenous asked for exhaustive medical tests about mercury contamination in hair samples instead of the urine sample [3]. Why is a hair sample better than urine? (a) mercury has a longer half-life in hair, so it can be useful for evaluating exposures that occurred months earlier, (b) mercury remains stable for long periods in hair, making it easy to transport and store, and (c) some mercury species, such as methylmercury, accumulate at higher concentrations in hair, making them relatively easy to measure [14]. To face the sanitary emergency, the government created and interinstitutional groups including Ministery of Health, The local government and, other institutions [10, 3]. The organisation AIDESEP has called the attention of the United Nations and the Inter-American Commission on Human Rights about the crisis. 

Peru ratified the Minamata Convention on Mercury, a legally-binding global treaty which commits parties to regulate artisanal and small-scale mining [16] but seems that at a national level there is still a lack of political will to protect indigenous groups from it. 

 Nahua Nanti are very concerned about what is happening and require explanations from the Peruvian authorities:  "We have no idea what is happening to us, so we demand that the authorities act." Said Jader Flores, indigenous Nahua Nanti [3]

According to WHO, health effects of mercury exposure encompasses harmful effects on the nervous, digestive and immune systems, lungs and kidneys, and may be fatal. The inorganic salts of mercury are corrosive to the skin, eyes and gastrointestinal tract, and may induce kidney toxicity if ingested. Neurological and behavioural disorders may be observed after inhalation, ingestion or dermal exposure of different mercury compounds. Symptoms include tremors, insomnia, memory loss, neuromuscular effects, headaches and cognitive and motor dysfunction. Mild, subclinical signs of central nervous system toxicity can be seen in workers exposed to an elemental mercury level in the air of 20 μg/m3 or more for several years. Kidney effects have been reported, ranging from increased protein in the urine to kidney failure. [8]