The water in Bangladesh was dangerous. Collected from rivers and lakes, it often carried diseases like dysentery and cholera, contributing to a mortality rate of 168 in 1,000 in vulnerable populations like infants in 1975 [1]. The fix was simple and fast: drill wells so the water would be clean, free from the bacteria that grew so quickly on surface water. The Bangladesh government and international nonprofits moved quickly, with over 8 million wells built in 20 years [2]. It was a revolution in less than a generation. Clean water was available in abundance, and the death toll dropped precipitously, over 100% over 20 years [3]. Drilling wells for clean water is a routine exercise around the world, as bacteria filled surface water is common in every human habitation. In this case, though, drilling so many wells so shallowly created an acute poisoning unique to the country of 173 million.

Arsenic (As) occurs in two forms: organic–containing carbon and passing easily through the body–and inorganic–lacking carbon and toxic to the living tissues it accumulates within. The element is widespread throughout the crust of the earth, most often found in minerals and in combination with metals, and it’s not rare. There’s more of it than either gold or silver [4]. While elemental arsenic doesn’t dissolve in water, many of the compounds it naturally occurs in readily do, and because of its prevalence throughout the crust there are certain hotspots where the ground water is laced at levels high enough to cause poisoning. Bangladesh is such a place.

Arsenic is a slow killer, with the full effects of the cell damage and death it causes not clear until months, or years, of exposure. Mortality is ultimately caused by cancers of the skin, bladder, and lungs, as well as pulmonary disease, cardiovascular disease, and diabetes. In children and infants, the progression is often faster, though the outcomes are largely the same. In effect, arsenic impairs nearly every major organ system in the human body. For those who survive, a substantial body of research has documented lasting consequences, including deficits in cognitive development, intelligence, and memory [5]. The World Health Organization has a maximum arsenic concentration of 10 micrograms per liter in drinking water guideline. The Bangladeshi government has set a less stringent limit of 50 micrograms per liter. Under the national standard, an estimated 35 million people are exposed to unsafe levels of arsenic. By the WHO benchmark, that figure rises to approximately 57 million—about 45 percent of the country’s population [6].

When widespread testing revealed that nearly half of Bangladesh’s shallow tube wells were delivering water contaminated with arsenic at potentially lethal levels, authorities launched a campaign urging communities to abandon those wells. The results have not had the intended effect. Shallow tube wells proliferated for a reason: they are inexpensive, easy to construct, and close to home. Residents were faced with stark choices: They could continue using contaminated water, seek out far rarer and often distant deep wells, or return to surface water sources. For a minority, deep wells offered a safer alternative. Most families did not have this option, and in households without access to deep wells, where arsenic-contaminated shallow wells were abandoned in favor of surface water, child mortality rose by 46 percent [2].

Arsenic laced drinking water is not restricted to Bangladesh. The same contaminated basin of water serves neighboring India, Vietnam, Cambodia, and Myanmar. Poisoning due to industrial actions is well documented in China and Canada. As a natural part of the crust, arsenic exists throughout the world, and significant amounts have been found in water sources in Argentina, Chile, and the US [7]. While some deepwater wells are free from arsenic, they’re not always available. Where they do exist, overreliance on them can cause problems like sinkholes and ecological damage [8]. The problem of Bangladesh is complex because an easily accessible, economical, and safe source of water does not exist. What can be tried instead is treating the water that is accessible and cheap in order to make it safe.

Why Arsenic is Difficult to Remove from Water

One reason arsenic contamination is so difficult to address is that arsenic does not behave as a single chemical species in water. Its toxicity and mobility depend heavily on its chemical form, which depends on local conditions. In oxygen-poor groundwater, like the shallow aquifers common in Bangladesh, arsenic is present primarily as As(III). In oxygen-rich environments, As(V) becomes more prevalent. Small shifts in pH and redox conditions can dramatically change arsenic’s chemistry and its treatability.

This chemical complexity has made arsenic removal one of the most challenging problems in water treatment. Arsenic appears at very low concentrations (micrograms per liter), yet still causes profound health impacts. Conventional remediation methods—such as precipitation, coagulation, ion exchange, membranes, or adsorption—can work under tightly controlled conditions, but no single method is universally effective [9,10]. Many require arsenic to be chemically converted from As(III) to As(V) before treatment, adding cost, operational complexity, and risk. Others generate arsenic-laden sludge that must be safely managed to avoid secondary contamination [11].

The challenge becomes even more severe in low-resource or rural settings. Researchers studying arsenic mitigation in Latin America and South Asia emphasize that sophisticated or maintenance-intensive technologies are often impractical where infrastructure, funding, and technical expertise are limited [9]. Treatment systems must be economical, simple to operate, and effective at extremely low arsenic concentrations. Without these attributes, even technically sound solutions fail to achieve lasting public-health benefits.

A Selective, Low-Waste, Low-Cost Alternative: MRT™

A different approach is to treat arsenic not as a bulk contaminant, but as a target for selective separation. Molecular Recognition Technology™ (MRT™) does exactly that. Rather than relying on broad chemical reactions, MRT™ uses highly selective ligands engineered to recognize and bind specific chemical species. In laboratory and field studies, MRT™ has demonstrated the ability to selectively separate both As(III) and As(V) directly from water at microgram-per-liter concentrations, without requiring pre-oxidation or extensive chemical conditioning [13].

In this process, contaminated water is passed through a column containing an AnaLig® resin. Manufactured by IBC Advanced Technologies, Inc., AnaLig® resins consist of a solid support functionalized with arsenic-selective ligands. As(V) species are selectively captured, while As(III) passes through and can be independently quantified or treated. The system has demonstrated arsenic recoveries exceeding 98 percent and excellent agreement with certified groundwater and wastewater reference standards [13]. Importantly, the material can be reused for more than 100 cycles without loss of performance, making it both cost-effective and operationally robust.

Unlike conventional methods, MRT™ aligns closely with green chemistry principles. Its high selectivity minimizes waste generation, eliminates the need for large volumes of added chemicals, and avoids producing unstable arsenic-laden sludge that poses long-term disposal risks [11]. Lower capital and operating costs, combined with reliable performance at very low concentrations, make MRT™ particularly well suited for regions where arsenic contamination is widespread but resources are limited.

Conclusion

The tragedy of arsenic contamination in Bangladesh illustrates a broader global challenge: access to water is not enough. Drinking water must also be safe. Shallow tube wells solved one public-health crisis only to reveal another, slower and more insidious threat. Arsenic’s complex chemistry, low-level toxicity, and persistence in groundwater have undermined many conventional treatment approaches, especially in regions where simplicity, affordability, and reliability matter most. MRT™ offers an innovative solution that targets arsenic with precision, operates effectively at trace concentrations, minimizes waste, and avoids the secondary pollution that has plagued earlier technologies. In doing so, it provides a practical path forward for protecting human health while respecting environmental and economic constraints.

Sources:

[1] D. Clark, (2025 November). Infant mortality rate (under one year) in Bangladesh from 1955 to 2020. Statista. https://www.statista.com/statistics/1073117/infant-mortality-rate-bangladesh-historical/#:~:text=Table_title:%20Infant%20mortality%20rate%20(under%20one%20year),Deaths%20per%201%2C000%20live%20births:%20182%20%7C

[2] Nina Buchmann, Erica M. Field, Rachel Glennerster, and Reshmaan N. Hussam, “Throwing the Baby out with the Drinking Water: Unintended Consequences of Arsenic Mitigation Efforts in Bangladesh,” NBER Working Paper 25729 (2019), https://doi.org/10.3386/w25729.

[3] Persson LÅ, Rahman A, Peña R, Perez W, Musafili A, Hoa DP. Child survival revolutions revisited – lessons learned from Bangladesh, Nicaragua, Rwanda and Vietnam. Acta Paediatr. 2017 Jun;106(6):871-877. doi: 10.1111/apa.13830. Epub 2017 Apr 19. PMID: 28295602; PMCID: PMC5450127.

[4] Emsley J (25 August 2011). Nature’s Building Blocks: An A-Z Guide to the Elements. Oxford University Press. ISBN 978-0-19-257046-8.

[5] World Health Organization (2022 December). Arsenic. https://www.who.int/news-room/fact-sheets/detail/arsenic#:~:text=The%20immediate%20symptoms%20of%20acute,and%20death%2C%20in%20extreme%20cases.

[6] Laura Padderson (2024 March). Tens of millions of people in this country drink arsenic-contaminated water. It could get a lot worse. CNN. https://edition.cnn.com/2024/03/21/climate/arsenic-contaminated-water-bangladesh-climate-intl

[7] Steinmaus, C.M., Ferreccio, C., Romo, J.A., Yuan, Y., Cortes, S., Marshall, G., Moore, et al., 2013. Drinking Water Arsenic in Northern Chile: High Cancer Risks 40 Years after Exposure Cessation, Cancer Epidemiol. Biomarkers Prev., 22, 523-630.

[8] EPA (2025 June). Ground Water. https://www.epa.gov/report-environment/ground-water

[9] Shakoor, M.B., Nawaz, R., Hussain, F., Raza, M., Ali, S., Rizwan, M., Oh, S.-E., Ahmad, S. (2017). Human health implications, risk assessment and remediation of arsenic-contaminated water: A critical review. Science of the Total Environment, 601–602, 756–769.

[10] Litter, M.I., Morgada, M.E., Bundschuh, J. (2010). Possible treatments for arsenic removal in Latin American waters for human consumption. Environmental Pollution, 158, 1105–1118.

[11] Shrestha, R., Spuhler, D. (2017 November). Arsenic removal technologies. Sustainable Sanitation and Water Management Toolbox. https://www.sswm.info/content/arsenic-removal-technologies

[12] Hayat, K., Menhas, S., Bundschuh, J., Chaudhary, H.J. (2017). Microbial biotechnology as an emerging industrial wastewater treatment process for arsenic mitigation: A critical review. Journal of Cleaner Production, 151, 427–438.

[13] Rahman, I.M.M., Begum, Z.A., Furusho, Y., Mizutani, S., Maki, T., Hasegawa, H. (2013). Selective separation of tri- and pentavalent arsenic in aqueous matrix with a macrocycle-immobilized solid-phase extraction system. Water, Air, & Soil Pollution, 224, 1–11. https://doi.org/10.1007/s11270-013-1526-0