Increase in drinking water salinity in Bangladesh heightens risk of pregnancy complications

At nine months pregnant, 22-year-old Rekha Begum was brought to Dacope Upazila Sadar Hospital on May 18 with trouble breathing.

“I could not even breathe let alone speak, and I was panicking so my mother brought me here,” Rekha, a resident of Gourdas Kathi village in Bagerhat’s Rampal Upazila, told the Dhaka Tribune. 

“This is my second pregnancy, and I did not feel this way when I had my first child five years back," she said. 

Dr. Md Mozaammel Haque Nizami, Dacope’s medical and family planning officer, said Rekha was suffering from gestational hypertension. He attributed it to increased levels of sodium chloride (salt) in drinking water in the coastal region.

“Although it is not uncommon during pregnancy, what is alarming is that the frequency of such cases is on the rise,” added Dr. Mozaammel, who runs the government hospital.

Gestational hypertension causes pregnant mothers to suffer from very high blood pressure and poses the risk of maternal death and stillbirth— according to doctors at the Sadar Upazila hospital. 

Like Rekha, many other women have been admitted to the hospital in last few years with similar symptoms. Between 2011 and 2014, the hospital’s records show a 36.9 percent rise in cases of pregnant women with hypertension.

Dr. Sontosh Kumar Mojumder, the hospital’s gynecology consultant, points out that many of the cases in recent years have transgressed the category of chronic and gestational hypertension and fall into that of pre-eclampsia, where patients endure high blood pressure alongside excessive muscle spasms. 

The frequency of such cases spiked 27.77 percent between 2012 and 2017, according to the hospital’s records.  

Sontosh links the rise in these cases to increased salinity in the coastal belt waters because when salinity is at its highest, during the dry season from November to May, more pre-eclampsia patients are admitted to hospital.

Additionally, joint research done in 2008 examining the correlation between drinking water salinity and maternal health in Bangladesh by London Imperial College and the Bangladesh Center for Advanced Studies found that the frequency of pre-eclampsia and gestational hypertension were higher in coastal areas compared to non-coastal areas.

The study, Drinking Water Salinity and Maternal Health in Coastal Bangladesh: Implications of Climate Change, also found that the frequency of these medical conditions rises during the dry season.

The salt predicament

Bangladesh’s coastal population, comprising approximately 40 million people, relies heavily on natural water sources like ponds, rivers and tube-wells for drinking water. 

However, seawater intrusion caused by environmental change and man-made factors (including poor water management and shrimp farming) have severely salinated these sources — as found by a government study conducted in the coastal region. 

Bangladesh’s Department of Public Health and Engineering (DPHE) determined that the salinity of groundwater in most areas in the coastal districts is several levels above the acceptable drinkable level — also when measured against amounts established by the World Health Organisation. 

The study found that in most coastal areas, the level of salinity (chloride count) in the main or secondary aquifer ranges from 103 to 12,433 milligrams/litre during the dry months and 34 to 11,366 milligrams/litre in the rainy season. 

In both cases, the extremes are far above the prescribed 300 milligrams/litre for freshwater and the drinkable range of 300-600 milligrams/litre.

Meanwhile, the 5th Assessment report of the Inter-governmental Panel on Climate Change (IPCC) places Bangladesh at particular risk from climate change because of its exposure to sea-level rise and extreme events such as salinity intrusion, drought, erratic rainfall and tidal surge.

Already salinity has encroached on areas more than 100km inland from the Bay of Bengal, and the impacts are projected to be exacerbated by sea-level rise caused by climate change. This jeopardizes the country's food supply, endangers public health and minimizes any livelihood security.

A study by the Centre for Environmental and Geographical Information Service (CEGIS), a subsidiary of Bangladesh’s water resources ministry, measured the average extent of seawater intrusion in Bangladesh’s coastal area and classified it into three sections.

The study -- Assessment of Sea Level Rise and Vulnerability in the Coastal Zone of Bangladesh through Trend Analysis -- which is based on 30 years of data, found that, on average, seawater intrusion in the Ganges tidal floodplain is 7-8mm per year; in the Meghna estuarine floodplain, it is 6-9mm per year; and along the Chittagong coastal plane it's 11-20mm per year. 

The poor pay more

While the wealthy and urban dwellers spend more on food, housing, water, and sanitation than those living in marginalised areas, the scenario is different in Bangladesh’s coastal belt.

Food, housing and sanitation are costlier in cities, but coastal area residents have to expend far more for water due to the salinity problem. 

Those living in Dhaka, the capital, pay the Water Supply and Sewerage Authority Tk8.49 (10 US cents) for a 1,000-liter unit of water for household use. Those living in Khulna, a city on the coastal belt, get it for nearly half that price, Tk4.50. 

Butthis is as far as the logic extends. Unfortunately, the situation across 19 coastal districts further south toward the coast that have been crippled by increased salinity is completely different.

Even those living just 20 kilometres from Khulna have to pay Tk10 for 20 litres of desalinised water. 

So for a 1,000-litre unit, people living in the coastal regions would have to pay Tk500, roughly 100 times more than what residents of the nearest city corporation, Khulna, pay.

Sacrificing well-being

Due to high costs, residents in the coastal region try to harvest rainwater to meet their needs during the three- to four-month monsoon. 

“During monsoon, we collect rainwater in our own harvesting pots for drinking,” said Taposhi Gayen, a resident of Dacope’s Saheber Abad village. “The rest of the months, we have to buy our drinking water.”

On average, the rates charged by both private and public providers are similar, Tk0.50 per litre. 

“So we try to use water from the ponds or rivers for washing, cooking and bathing—as using desalinised water would be impossible to afford,” added Taposhi. 

Incidentally, the salinity-affected districts fall mostly under the Barishal and Khulna divisions— both of which recorded a monthly household income below the national average during a survey conducted by the Bangladesh government in 2010.

The Bangladesh Bureau of Statistics said in the report, Household Income and Expenditure Survey 2010, that the national average income stood at Tk11,479 — while Barishal’s was Tk9,158 and Khulna’s was Tk9,569. 

Mira Gain, a 45-year-old mother of three, buys drinking water for her family from a saline water treatment plant of the local union parishad complex in Dacope. 

The five-member family can only afford Tk300 per month for drinking water, which, at the standard rates, gets them 600 litres. Each member must sustain themselves on just four litres of desalinised water per day.

“Thus, they try to make up the shortage by using saline water for cooking and other purposes, which ends up having severe health impacts in the long run,” hydrologist Prof. Ainun Nishat said. 

Banner image: Saline water is the source of gestational hypertension causes pregnant mothers to suffer from very high blood pressure and poses the risk of maternal death and stillbirth / Credit: Abu Siddique