Droughts brought on by climate change are making Bangladesh’s groundwater situation worse, putting the country’s food and health security at risk, and raising arsenic poisoning to dangerous levels in several regions.
According to a recent study, rice and vegetables cultivated in arsenic-affected areas contain dangerous levels of the metal, which might seriously harm human liver and kidneys if consumed over time.
The research team, which was led by Prof. Dr. Laila Khaleda, Chair of Chittagong University’s Department of Genetic Engineering and Biotechnology, comprised Md. Mazharul Alam, Prof. Dr. Mohammad Al-Forkan, Lecturer Zarin Tasnim of Chittagong Veterinary and Animal Sciences University, and a number of other scientists from the Bangladesh Medical University.
The study, funded by the Ministry of Science and Technology and the Bangladesh Medical Research Council, was conducted between January 2021 and January 2023 in two arsenic-contaminated upazilas of Chandpur, Hajiganj and Shahrasti.
Their findings were published on June 14, 2025 in the international journal Toxicology Reports (Elsevier).
Although previous studies in Bangladesh identified arsenic in rice, vegetables, and groundwater, this is the first research to experimentally demonstrate how contaminated food affects health.
The research revealed that arsenic levels in water, soil, and crops from the study areas far exceeded international safety limits. Groundwater samples contained up to 0.373 mg/L of arsenic, almost 30 times higher than the World Health Organization’s (WHO) safe limit of 0.01 mg/L.
While rice had up to 0.91 mg/kg of arsenic, more than double the WHO’s allowable limit of 0.37 mg/kg, soil had 32.51 mg/kg, more than three times the global average.
The highest levels of arsenic contamination were seen in edible ferns, where levels reached 1.93 mg/kg, over four times the permissible limit.
Arsenic levels in crops, soil, and irrigation water were shown to be strongly positively correlated by researchers, demonstrating how contamination spreads throughout the food chain and poses major risks to both humans and animals.
Six groups of Wistar albino rats were used in the controlled trials; two were control groups, and four were fed rice that was both arsenic-free and contaminated with arsenic, as well as edible fern.
Rats fed tainted food during a 120-day period displayed decreased appetite, weight loss, low red blood cell and hemoglobin counts, higher liver enzymes, and elevated kidney toxicity indicators.
Under the direction of Prof. Dr. Md. Zillur Rahman, histopathological analyses showed necrosis, cellular damage, and fat buildup in the liver and renal tissues.
“We observed distorted cells, inflammation, and signs of chronic toxicity-evidence that arsenic damages organs directly, not just through blood,” Dr. Rahman said.
Experts warned that arsenic, often regarded only as a groundwater contaminant, has now infiltrated Bangladesh’s food chain. “This research proves that food is now a silent source of arsenic exposure,” said research assistant Md. Mazharul Alam.
“Immediate actions such as ensuring arsenic-free irrigation, safe soil management, and regular food testing are essential to protect public health,” he added.
Lecturer Zarin Tasnim described the findings as “a serious warning for public health,” saying that contaminated food silently introduces toxins into human bodies, particularly threatening children, women, and the elderly.
Prof. Dr. Mohammad Al-Forkan emphasized the national significance of the study. “This is not just an academic study, it exposes a real problem. Arsenic-contaminated irrigation water seeps into the soil, is absorbed by crops, and eventually reaches our plates. It’s a direct warning about our future.”
Lead researcher Prof. Dr. Laila Khaleda said the team’s work goes beyond chemical analysis to demonstrate biological damage caused by arsenic exposure through food.
“Feeding arsenic-laden rice and vegetables for several months caused liver and kidney damage in animal models. Prolonged human exposure could lead to cancer, kidney failure, liver cirrhosis, and other chronic diseases,” she said.
In order to routinely check for arsenic contamination in food crops, soil, and irrigation water, the researchers recommended that the government set up a nationwide monitoring system.
“Our findings carry an important message for the people of Bangladesh,” Professor Khaleda emphasized. Food contamination has long-term effects but damages at levels that are imperceptible to the human eye. Arsenic poisoning might cause a long-term national health emergency if the government does not act right now.
To stop arsenic from moving up the food chain, experts also advocated for regular food supply testing, increased public awareness, and sustainable irrigation techniques.
The researchers caution that arsenic pollution is not a regional problem because Bangladesh is still largely dependent on agriculture, with rice serving as both its primary crop and staple food. Millions of people may be unwittingly at risk since rice produced in impacted areas is transported throughout the nation.
“Arsenic is a silent killer,” added Professor Khaleda. “If we fail to act now, we may face an invisible epidemic threatening the health of future generations.”
