“Baby foods used to wean infants off milk have been found to contain ‘alarming’ levels of toxic contaminants including arsenic, lead and cadmium,” The Daily Telegraph has reported.
The news is based on a Swedish study that tested a number of formula milks and weaning foods for levels of various essential and toxic minerals. Some foods, notably rice products, had relatively high levels of arsenic, although it is unclear whether these cause harm. Overall, the findings of this study raise questions about the suitability of rice in infant foods and highlight the need for further research to establish the levels of the different elements that infant foods may contain. This applies both to the substances that are known to be toxic beyond a certain level and to the essential elements that are required by the body to maintain health.
This study is not the first to look at toxic elements in baby foods, with the UK’s Food Standards Agency having previously looked at how these substances might affect infant health. The agency concluded that levels of cadmium and other environmental contaminants in these foods were not a concern for infant health, although it did recommend keeping exposure to arsenic to a minimum. In line with this precautionary measure they have already recommended that babies are not given rice milk in place of breast milk or regular formula.
Where did the story come from?
The study was carried out by researchers from the Karolinska Institute in Stockholm and was funded by the Swedish Government’s VINNOVA Agency for Innovation Systems, the EU and the Karolinska Institute. The study was published in the peer-reviewed scientific journal Food Chemistry.
The press has widely covered this research, generally reporting its findings in a manner that may cause alarm for parents. Many of the heavy metals found in the tested foods were within the current official safety limits set out by the European Commission. However, for certain chemical elements there are not yet clear guidelines on what should be considered safe levels and the researchers also question the methods by which some of these guidelines have been established. These, ideally, need to be confirmed through further research.
What kind of research was this?
This was observational research that tested the levels of toxic and essential elements (those needed by the body) found in formulas and foods intended for infants in their first six months of life. The researchers introduce their research by discussing the international statistics relating to breastfeeding and to eating solid foods. They note that exclusive breastfeeding is recommended for the first six months of life, but that many infants are unlikely to be exclusively fed breast milk to this age, and that approximately two-thirds of infants in Europe are fed some solid food at four months of age.
In order to increase what is known about infant exposure to different elements, Swedish researchers set up a study to measure the concentration of essential and toxic elements in infant formulas and infant foods that are intended to be consumed within the first six months of life. The researchers assessed the levels of the essential elements calcium, magnesium, iron, zinc, copper, manganese, molybdenum and selenium. They also assessed levels of the toxic elements arsenic, cadmium, antimony, lead and uranium.
What did the research involve?
The researchers examined nine infant formulas and nine infant foods that were all intended for consumption after the age of four months. The content of the formula milks was compared with that of breast milk. Most of the formula products are available worldwide, made by large manufacturers, come in powdered form and are prepared by adding a recommended ratio of liquid. They looked at the following infant milks:
- breast milk
- two types of organic milk formula
- two types of plain milk formula
- milk, partly hydrolysed formula
- casein, extensively hydrolysed formula
- whey, extensively hydrolysed formula
- milk, rice and starch formula
- soy protein formula
They looked at the following infant foods intended for consumption after four months of age:
- breast milk
- formula milk
- spelt flour
- two types of wholegrain rice
- two types of rice and banana
- rice and locust bean
Concentrations of the various elements were assessed in a standard way (in micrograms per litre) and these were compared between the different fluids using standard statistical tests. In order to provide a clear illustration of how formula feeding might differ from breastfeeding, they compared the concentrations in the formula foods with existing published data about the levels of different elements in breast milk.
They also calculated how many grams of the elements infants would be consuming per day and on a per-portion basis for each infant formula and infant food.
What were the basic results?
The study found wide variations in the concentrations of most essential and toxic elements in infant formula and foods, and that these variations largely depended on the ingredients that were used. In the foods that were fortified with essential elements (often iron, zinc, molybdenum and manganese) levels of these substances were many times higher than those found in breast milk.
They say that the most concerning findings are high levels of manganese, iron and molybdenum and the low levels of the essential element selenium in some formulas. They consider the high levels of arsenic in rice-based foods to be of concern too. They note that two of the rice-based foods had high concentrations of all toxic elements and all essential elements (except selenium). The researchers go on to discuss these different elements in more detail.
How did the researchers interpret the results?
The researchers highlight the varying concentrations of different elements in infant formula and foods and say they are concerned by the levels of potentially toxic compounds, including arsenic, as well as the high levels of some of the essential elements, such as iron.
The research has compared the concentration of different chemical elements (both essential and potentially toxic) found in a range of different infant foods and formulas. The levels of many of these elements are higher than those found in breast milk.
This is not the first time that research has looked at the presence of heavy metals in baby foods. In 2003 and 2006 the UK’s Food Standards Agency tested the levels of these potentially toxic substances in foods and had the results examined by a committee that specifically considered how they might affect infants. The committee concluded that the levels of environmental contaminants such as cadmium were not a concern for infant health, although they did suggest that exposure to arsenic and lead should be kept as low as possible.
Also, the authors of this new study have expressed concern at the high levels of arsenic in rice-based products. The FSA acknowledges that babies’ intake of inorganic arsenic should be kept as low as possible, and accordingly monitors the levels present in a range of baby products:
- Based on their testing the FSA recommends that babies and toddlers should not be given rice drinks, often referred to as rice milk, as a replacement for cows’ milk, breast milk or infant formula. The FSA made the recommendation as a precautionary measure and says that there is no immediate risk to children who have been consuming rice drinks, which would be unlikely to cause any long-term harmful effects.
- A 2007 survey by the FSA also examined the levels of arsenic in baby rice and other rice-based weaning foods. The agency concluded that these foods did not have levels of inorganic arsenic that caused concern.
In response to this news the Food Standards Agency has issued the following statement:
“The Agency takes this issue very seriously and has conducted a number of studies that reviewed the levels of arsenic, cadmium, lead and other contaminants in baby foods. These substances occur in the environment and are as a result present at low levels in foods.
“Significant studies conducted by the Agency in 2003 and 2006 were both reviewed by the Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment (COT), an independent committee of experts in the field. The Committee specifically considered the susceptibility of infants to these substances. The Committee concluded that levels of cadmium and other environmental contaminants that were found were not a concern for infant health. The Committee acknowledged that exposure to arsenic and lead should be kept as low as possible.
“The Agency is actively engaging with the European Commission to review and establish long term limits for these environmental contaminants in food.”
It is also worth mentioning that many of the newspapers have only reported the findings concerning the potentially toxic compounds, including arsenic, but have failed to point out that some of the tested foods contain much higher levels of essential elements than breast milk.
Analysis by Bazian
Edited by NHS Website
Links to the headlines
Daily Mail, 11 April 2011
The Daily Telegraph, 11 April 2011
The Daily Telegraph, 11 April 2011
Links to the science
Food Chemistry, Volume 127, Issue 3, August 1 2011, Pages 943-951