On a cloudy winter's day in El Chañaral, an old Indigenous Wichi community in northern Argentina, the Bustamante family's daily reality revolves around a silent, invisible threat. Their seven-year-old daughter, Marcela, plays near a reservoir of greenish-brown water, unaware it contributes to the pain she feels in her bones.
Marcela Bustamante belongs to the Cuellar family, where many members show symptoms of endemic regional chronic hydroarsenicism (Hacre). This debilitating illness is caused by prolonged consumption of water containing dangerously high arsenic levels.
The Poison in Their Water
While Argentina's Food Code, aligning with World Health Organization recommendations, sets the maximum permitted arsenic level in drinking water at 0.01 milligrams per litre, the reality in the Copo department is starkly different. Official reports indicate levels here range between 0.4mg/l and 0.6mg/l – up to sixty times the safe limit.
The most recent hair tests on Marcela's mother, Lidia Cuellar, revealed a concentration of 2.24 micrograms per gram. This staggering figure is 224 times the legal level permitted in Argentina.
Santiago García Pintos, founder of social development organisation Cynnal, explains the devastating health impacts. "Some symptoms are quite identifiable," he says. "You can see in children that they have hardened skin and develop freckle-like marks. In adults, it begins to crack and split, and that can lead to skin cancer. Teeth start to stain, and eventually, they fall out."
He adds that arsenic is known to cause kidney and liver cancer, and is suspected in many lung cancer cases in the region.
A Family's Painful Legacy
Lidia Cuellar, a slender woman who speaks in a whisper, follows family tradition by drinking mate tea using rainwater collected from a cistern. All groundwater in these remote areas, drawn from wells due to the absence of piped water networks, is contaminated with arsenic and fluoride.
Their safety depends entirely on rainfall, but severe droughts and inadequate infrastructure often force them to rely on state water tankers during the hot season. When the cistern runs dry, their choices are bleak: buy questionable water from the river or consume the arsenic-laden reservoir water.
When Cuellar was seven years old, her father died from the effects of arsenic-contaminated water. "A water network is the most urgent thing we need," she says, believing the contaminated water causes her and her daughter's recurring bone pain.
Her uncle, Erasmo Cuellar, lives in Vilmer, one of the areas with highest arsenic concentrations. His hands are calloused, his back shows white spots, and lesions mark his ears. "I drank that water from age four until about twenty," he reveals. "There were eight of us. Only two are alive now. Seven of us fell ill with cancer and six have died."
A National Health Emergency
This is not an isolated crisis. Of Argentina's 45.8 million population, approximately 4 million people live in areas with high arsenic concentrations in groundwater. More recent research from the National University of Rosario suggests the number exposed could be as high as 17 million.
Studies indicate that up to 30% of Hacre patients in Argentina develop cancer, particularly affecting the skin and internal organs. This has been a longstanding issue – back in 2001, the health ministry estimated about one million people were exposed, mainly in Tucumán, Santa Fe, La Pampa and Santiago del Estero, where 100,000 people showed contamination symptoms.
Unlike many global cases, Argentina's arsenic contamination occurs naturally through geochemical processes, with the element leaching from volcanic rocks into groundwater rather than originating from industrial pollution.
In November 2006, the Provincial Programme for Endemic Regional Chronic Hydroarsenicism was established to investigate and prevent arsenic and fluoride entering water sources. Natividad Nassif, health minister of Santiago del Estero, states: "The province has developed policies to bring safe water to the towns and settlements most affected by arsenic and fluoride."
However, García Pintos disputes these claims. Having lived in the area from 2018 to 2021 and visiting regularly since, he states: "I can assure you that the government isn't purifying water to remove arsenic in that region. There are no water networks or any treatment to make it fit for human consumption."
While the ministry states that water and hair samples are regularly collected from affected communities including San José del Boquerón, Piruaj Bajo and Vilmer, families like the Bustamantes continue to suffer.
For Marcela, who dreams of becoming a teacher, the future remains uncertain. Her mother doesn't take her for regular health checkups, relying instead on occasional visits from doctors to her school. Beyond the health crisis, the family faces another dire challenge – sometimes, there's simply nothing to eat.
Effective technologies exist to treat arsenic-rich water, adaptable for both municipal plants and household filters. Yet for Argentina's rural communities, these solutions remain frustratingly out of reach, leaving generations to bear the devastating consequences of poisoned water.
