Lizama-Allende et al. 2022 — Arsenic and boron in Chilean Altiplano-Puna surface waters, 2008–2018
This 10-year monitoring study assessed water quality at multiple stations in the Chilean Altiplano-Puna region across 2008–2018. The primary finding is that most monitoring stations exceeded Chilean drinking water standards for arsenic and boron throughout the monitoring period. Elevated arsenic levels are attributed to naturally high geological sources, specifically volcanic and geothermal activity in the Atacama region rather than anthropogenic contamination. The study documents persistent and geographically widespread arsenic exceedances in surface waters used as drinking water sources in an arid high-altitude region.
Key numbers
- Most monitoring stations exceeded the Chilean drinking water standard for arsenic (50 µg/L under the Chilean standard at time of study) at some or all time points across the 10-year period.
- Arsenic is predominantly naturally sourced from volcanic geology in the Altiplano-Puna system.
- Boron also exceeded standards at multiple stations.
- 10-year dataset covering 2008–2018; multiple sampling stations.
- Total arsenic (tAs) measured; inorganic speciation not reported in the paper’s main analysis.
Methods (brief)
Long-term water quality monitoring program. Water samples collected from surface water monitoring stations in the Altiplano-Puna region of northern Chile. Standard water chemistry analyses including ICP-MS or ICP-OES for arsenic and boron. Exceedance assessed against Chilean NCh 409 drinking water standard (50 µg/L As at time of study, prior to the update to 10 µg/L WHO guideline value).
Note: This paper reports total arsenic. The iAs/tAs distinction cannot be resolved from this source; the tAs field reflects the reported measurement. Naturally occurring arsenic in Andean waters is predominantly inorganic arsenate (As(V)).
Implications
Certification: Relevant for supply-chain water source risk; brands sourcing ingredients from northern Chilean agricultural regions should assess whether irrigation water draws from Altiplano-Puna surface water systems. Courses: Illustrates natural geogenic arsenic contamination as distinct from anthropogenic; important for supply-chain geography modules. App: No food product concentration data; this is a water source characterization relevant to ingredient origin risk assessment.