Lead has long been known to be bad for the health of those who consume it, and measures have been implemented internationally to limit metal inadvertently entering into people’s bloodstreams. It is particularly troubling then, that a report from the Environmental Defense Fund (EDF) In the US found that after analysing 11 years of data published by the US Food & Drug Administration (FDA), 14% of 10,064 food samples were found to contain detectable levels of lead, including 20% of the 2,164 samples of baby food analysed.

The findings are particularly pertinent when taking into account the advice of various health bodies, including US Center for Disease Control and Prevention (CDC), and the UK NHS state that there is no known ‘safe’ level of lead that can be ingested – any amount has the potential to cause complications.

Lead-poisoned baby food

The highlighted 20% figure does not fully portray how badly certain varieties of food within the samples analysed breached the limits put in place by the FDA and other international governmental health bodies. The EDF found that 45% of pear juice, 55% of apple juice and 89% of grape juice samples meant for young children were found to contain detectable levels of lead. Root vegetables were also particularly noteworthy offenders, with 86% of sweet potato samples and 43% of carrot samples being flagged up as containing identifiable levels of the heavy metal.

The FDA set its maximum intake limit for lead at 6 micrograms (μg) a day in 1993, but this exposure level was based on the science available at the time, and has not been updated alongside modern standards, except for fruit juice, which follows international guidelines.

The EDF also raised the fact that baby food was frequently found to contain more lead than their equivalent generic varieties of food as a matter of grave concern, particularly given that health implications as a result of ingesting lead are known to be much more severe in children. One example provided was that only 25% of regular apple juice contained detectable levels of lead, compared to the 55% found in baby apple juice.

The catastrophic health impacts of lead in the diet

According to the World Health Organisation (WHO), “Lead is a cumulative toxicant that affects multiple body systems” and is “distributed to the brain, liver, kidney and bones. It is stored in the teeth and bones, where it accumulates over time.”

While the health risks are severe in adults, including high blood pressure and kidney damage, it is children who suffer the worst effects, with under-fives being the most heavily impacted. Children absorb 4-5 times more lead from any given source than adults, making them incredibly vulnerable. Even miniscule amounts of lead have been shown to have a significant effect on children’s brain function, causing difficulty in school, and permanently impacting their mental performance. The European Food Safety Authority (EFSA) calculated in 2010 that a lead intake of 0.5μg per kilogram (μg/kg) per day correlates with a 1 point decrease in IQ. The EDF estimates that the US economy would be improved by $27bn per year, purely on the basis of the population having a greater IQ, before savings on healthcare etc. are even considered.

"Even miniscule amounts of lead have been shown to have a significant effect on children’s brain function, causing difficulty in school, and permanently impacting their mental performance."

As well as the intellectual implications, the WHO states that in children lead exposure can cause anaemia, hypertension, renal impairment, immunotoxicity and toxicity to the reproductive organs, all of which, including the discussed neurological damage, are thought to be irreversible.

In addition, for pregnant women lead is also known to impact their unborn child, resulting in the potential for miscarriage, stillbirth, premature birth, low birth weight, and minor malformations in the foetus.

How is it getting into our food?

An EDF consultant Maricel Maffini stated that “We don’t know precisely where the lead in food is coming from… contaminated soil is one likely option,” though did admit that this did not explain why baby foods were more heavily affected than regular varieties. 

Lead was at its peak use in the early 1970’s, where it was used extensively as part of paint, in gasoline, and in water pipes. Later on in the 70s evidence of its impact on health became more prevalent, and its use has been significantly drawn back since that time, being eradicated in most instances. Encouragingly, according to CDC statistics, average blood lead levels in children under 5 in the US fell from 17μg per decilitre (dl) in 1978, to 4μg/dl in the 1990s.

Some areas of land do contain geochemical lead, naturally occurring ‘organic’ lead that is naturally found in the soil, however it is believed historic use of lead in fuels and in other industrial activities, such as mining and smelting have caused the contamination in soils across the US and EU. According to the US Environmental Protection Agency (EPA) atmospheric lead can travel long distances before settling, causing widespread harm.

When asked for comment, a spokesperson from the FDA provided that “It is important for consumers to understand that lead is in food because it is in the environment and lead cannot simply be removed from food. The FDA has monitored levels of lead in foods for decades and tests for of a wide range of foods that are representative of the diet of the US consumer. Although lead is still present in many foods, of the 8,801 foods collected and analysed between 2005 and 2013, 88% had levels that were too low to be detected.”

“We determine, on a case-by-case basis, whether to take enforcement action when we find foods that are contaminated with lead. The agency is in the process of re-evaluating the analytical methods it uses for determining when it should take action with respect to measured levels of lead in particular foods, including those consumed by infants and toddlers.”