Bangladesh: Sea Level Rise, Floods Can Release Risky Levels Of Arsenic Into Drinking Water, Cause Cancer Among Residents

(Photo : Getty Images/MUNIR UZ ZAMAN)

In Bangladesh, experts feared about the risky levels of arsenic that can be released into the drinking water, which can later cause cancer among the public, according to recent reports.

The dangerous level of arsenic could be brought by sea level rise as well as high floods.

Public Health Crisis

Experts warned that this could be an intensification of a public health crisis, which is already affecting the country. So far, millions of residents have skin, bladder and lung cancers as a result of arsenic poisoning.

Based on records, around 165,000,000 people live in Bangladesh wherein approximately 97% of Bangladeshis drink well water.

Approximately 49% of Bangladesh's area has drinking well water with arsenic (As) concentrations that exceed the 10 micrograms per liter (μg/L) of the World Health Organization (WHO) guideline.

This exposure to a potent carcinogen is a significant threat to public health.

About 21% of Bangladesh is flooded each year during a typical monsoon season. As climate change progresses, sea levels will continue to rise, and the area and duration of these annual floods will increase.

Due to this phenomenon, scientists believed that these consequences of climate change can increase the release of arsenic from sediments into Bangladesh's drinking well water.

Alluvial sediments deposited in Bangladesh's lowlands during the Holocene epoch, or 11,700 years ago, have minerals that often contain arsenic.

These minerals release arsenic into Bangladesh's groundwater. Experts said that this groundwater is used for drinking.

Groundwater For Drinking

To recall, the use of groundwater for drinking has increased tremendously since the 1970s when the government of Bangladesh, United Nations International Children's Emergency Fund (UNICEF), and some non-governmental organizations (NGOs) began installing about 10,000,000 drinking water wells in the said country.

Prior to 1970, surface water was the most common source of drinking water in Bangladesh.

However, a huge portion of the country's area has high arsenic concentrations. This new and very large exposure to arsenic in Bangladesh's drinking water has been increasing the rates of death and disease from skin, bladder, liver, and lung cancers and vascular diseases.

The arsenic containing minerals that are contaminating Bangladesh's groundwater are a mixture of iron (Fe) oxyhydroxides and manganese (Mn) oxyhydroxides. Arsenic is released from these minerals into drinking well water by reduction.

The reducing environment is often enhanced by seasonal flooding from the annual monsoons and cyclones, and by the cultivation of rice in flooded paddies.

These floodwaters are a barrier to the diffusion of oxygen, which is a very strong oxidizing agent, from the atmosphere into the aquifer.

Furthermore, dissolving these bulk minerals may also release arsenic into Bangladesh's drinking well water.

As the climate changes and sea levels rise and flooding increases, the release of arsenic into Bangladesh's drinking well water by reduction is expected to increase, causing significant health issues to exposed citizens.

Rising sea levels can cause an increase in the salt concentration of the underlying aquifer; this should increase the release of arsenic from sediments into the drinking well water by the salt effect.