Breast milk samples from 40 breastfeeding mothers were found to be “highly contaminated” with uranium, according to a study published in the journal Nature. However, it noted that the contamination had “minimal impact on maternal and infant health”.
40 mothers between the ages of 17 and 35 took part in the research. This study was conducted in selected districts of Bihar which included Bhojpur, Samastipur, Begusarai, Khagaria, Katihar and Nalanda. The study was conducted from October 2021 to July 2024.
What the study revealed
Breast milk samples from women from six districts of Bihar were analyzed. These districts were Bhojpur, Samastipur, Begusarai, Khagaria, Katihar and Nalanda.
The study revealed that “all samples had uranium content”. It read: “The present study indicates that 100% of nursing mothers have their breast milk highly contaminated with uranium.”
The highest concentration of uranium in breast milk was observed in Katihar district – 5.25 µg/l. The study showed that samples from Katihar district had “hazardous levels” of uranium (U238) in breast milk samples.
The descending order of exposure to uranium contamination in districts was as follows: Katihar > Samastipur > Nalanda > Khagaria > Begusarai > Bhojpur.
“However, the reported concentrations are below the permissible limits, and therefore exposure to uranium could represent the least significant health threat,” the study added.
Is there an acceptable limit for uranium in breast milk?
No. Currently, there is no established permissible limit or benchmark for the concentration of uranium in breast milk. However, the World Health Organization (WHO) sets the permissible levels of uranium in groundwater at 30 µg/l.
What is the source of uranium?
The study revealed significant presence of uranium in groundwater samples from Bihar. “The source of uranium contamination in the six studied districts could be sources of drinking water or sources of food grown in the same location,” the study said.
It showed that the maximum concentration of uranium in groundwater samples was reported as 82 µg/lv of Supaul district, followed by 77 µg/lv of Nalanda district and 66 µg/lv of Vaishali district in Bihar.
The study also noted that extensive use of groundwater for drinking and irrigation has led to contamination of groundwater with various pollutants in the eastern state of Bihar.
“The discharge of untreated or inadequately treated industrial wastewater into rivers and other water bodies contributes to the pollution of the aquatic ecosystem,” it said.
“This pollution can introduce heavy metals and other toxic substances into the food chain, which ultimately affects human health. The use of chemical fertilizers and pesticides in agriculture can lead to the contamination of soil and water resources with these harmful substances,” it added.
Meanwhile, co-author Dr. Ashok Sharma of AIIMS was quoted by the Times of India as saying that the source of the contamination remains unclear and the Geological Survey of India is also trying to find out.
However, he suggested that uranium enters the food chain and causes cancer, neurological disorders and affects the growth of children, which is a very serious problem.
How can it affect the concentration of uranium in breast milk?
The study showed that uranium contamination in breast milk could pose a health concern for exposed infants and could lead to low IQ, impaired neurological development and a host of mental health problems.
However, the study showed that uranium toxicity has the least impact on the exposed mother and her infants. Here’s why:
“Its exposure can affect the neurological development of infants, which can lead to cognitive and behavioral problems,” the study said. “It can also increase the risk of developing cancer later in life,” he added.
However, uranium preferentially accumulates in bones and kidneys due to its affinity for phosphate and carbonate groups, rather than in breast milk.
“Its low affinity for milk components (lipids, proteins and water) combined with the absence of specific transport mechanisms leads to low concentrations of uranium in breast milk,” he said.
“The primary route of excretion is urine, which can reduce the impact of uranium in the infant’s body,” he added.
Who conducted the study?
The study was conducted at Mahavir Cancer Sansthan and Research Centre, Patna, Bihar. The researchers received assistance from the Indian Council of Medical Research, Government of India and the National Institute of Pharmaceutical Education and Research (NIPER)-Hajipur, Vaishali, Bihar.
Key things
- 40 breast milk samples from nursing mothers were found to be “highly contaminated” with uranium, but the health impact is minimal.
- Katihar district had the highest concentration of uranium in breast milk at 5.25 µg/L, but the levels are below the permissible limits.
- Uranium contamination in breast milk can affect an infant’s neurological development, but has little impact due to low concentrations.
