Even in small quantities, the nitrates contained in the drinking water that mothers consume before and during their pregnancy, would lead to a reduction in the weight of their newborn.
- Analysis of birth records in Denmark revealed that babies exposed in utero to thresholds between 25 and 50 milligrams of nitrates per liter weigh on average ten grams less than other children.
- Birth weight affects health throughout life
Created during the nitrogen cycle, nitrates (NO3-) are ions present naturally in the environment, and in particular in water. Although essential to human health, nitrates can be harmful to the body when they are concentrated in excessive quantities in drinking water. They prevent the body from absorbing oxygen, leading to the dangerous blue baby syndrome, or methemoglobinemia, in young children, caused by the blood’s reduced ability to carry vital oxygen throughout the body. . An excess of nitrates can also cause chronic diseases such as intestinal cancer, hence the setting of a maximum threshold of 50 milligrams of nitrates per liter of water within the European Union.
A new Danish-American study, led by Professor Torben Sigsgaard of the Department of Public Health at the University of Aarhus (Denmark), sheds light on the impact that nitrate has on the weight of babies when their mother drinks a nitrate-rich water before and during pregnancy. She just appeared in Environmental Health Perspectives.
Smaller and smaller babies
The researchers based their work on registers of more than 850,000 registered births in Denmark, from which they collected various data. After analysis, they concluded that babies born to mothers who drank water containing between 25 and 50 milligrams of nitrates per liter (half the current threshold value up to the maximum limit) weigh on average ten grams less. than babies born to mothers whose tap water contains smaller amounts of nitrates.
They found that the babies not only weighed less, but were also slightly shorter. On the other hand, the growth of the cranial circumference was not affected by the quantity of nitrate.
“The difference in length and weight of the body does not seem significant at first sight since it is on average only ten grams, but it is not negligible if the newborn also begins life underweight for d other reasons, emphasizes Professor Sigsgaard. It is generally accepted that birth weight has an impact on a person’s health and development throughout their life.
According to him, these results undoubtedly call into question “the threshold value in force in the Western world”. “Through this study, we have established that it is necessary to explore the effect of low nitrate concentrations in drinking water, if we are to assess the adequacy of the current threshold values - and this is possible thanks to the registers Unique Danes”concludes Professor Sigsgaard.
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