The recent death of Baltimore man Freddie Gray, who’s spinal cord was apparently snapped when in police custody, has sparked not only an investigation into police practices but has also reinvigorated the discussion around the potential effects of lead poisoning in children.  Despite long being known to be harmful, the effects of lead paint in the homes of children are still being discovered and surprisingly, are still having an effect.  The question of the moment, though, is can lead poisoning in children ultimately lead to criminal behavior in adults?

 Lead Paint and its Effects

     Although the practice of putting lead into paint was banned in 1978, many homes, especially in poor socio-economic areas, still have lead paint on the interior and exterior walls.  In time, this paint deteriorates and will chip or release dust that can either be breathed in or more likely swallowed by children.  It wasn’t so long ago that 10 micrograms of lead per deciliter of blood was considered a safe level.  However in 2012, following a 30 year study into the effects of lead poisoning, the Center for Disease Control and Prevention (CDC) reduced that number to just five micrograms per deciliter.  Now, many argue that there is no safe level at all[1].  What’s even scarier is that in 2007, an estimated 25% of homes still contained deteriorating lead paint and currently, more than four per cent of children in the US have some level of lead poisoning.  These figures rise in big cities and poor urban areas. 

     Lead poisoning in adults is relatively rare and it is the effects that it has on children that are most worrying, as it can affect their developing nerves and brain[2].  Of course there are physical effects such as stomach cramps, sleep deprivation, and sickness, but ultimately, it’s the longer term cognitive effects that create such a furore.  Ruth Ann Norton, the executive director of the Coalition to End Childhood Lead Poisoning states that “a child who was poisoned with lead is seven times more likely to drop out of school and six times more likely to end up in the juvenile legal system”[3].  Similarly, in 2007, a five-year study of 780 children shows that lead poisoning leads to lower IQs and a higher instance of learning and behavioral problems in school aged children.  These children, it was claimed, were more likely to be aggressive, inattentive, and impulsive[4].  Kim Dietrich, a professor of environmental health and director of the division of epidemiology and biostatistics at the University of Cincinnati, who is currently following a 30 year study of 350 individuals exposed to lead paint, even claims that lead poisoning can ultimately lead to criminal activity[5]

 Freddie Gray: A Case Study

     In 2009, Gray, along with his sister, mother, and a number of other families appeared in court in relation to a lead-poison lawsuit.  It was revealed that Gray, born in August 1989, had spent his childhood in a house littered with peeling lead paint and lead paint chips.  Blood tests in May 1990 showed 10 micrograms of lead per deciliter of blood.  Three months later, that had shot up to 30 micrograms.  By June 1991, his blood contained a shocking 37 micrograms of lead per deciliter.  In his deposition, he explained how his twin sister Fredericka was often aggressive and how they had both suffered from problems with concentration and attention[6].  They won the lawsuit with an undisclosed settlement. 

     Gray’s life, even up until his tragic end, was littered with misdemeanours and criminal activity.  He had been arrested 18 times, mostly for the sale and possession of heroin and marijuana, but also for aggression and violence[7].  In the wake of his death, many have asked whether his lead poisoning as a child could have inevitably lead to his criminal behavior.  Dan Levy, assistant professor of pediatrics at the Johns Hopkins University suggests that “the fact that Mr Gray had these high levels of lead in all likelihood affected his ability to think and to self-regulate and profoundly affected his cognitive ability to process information[8].” 

 Can There Be Other Factors?

    Since the negative effects of lead poisoning rise so dramatically in poor socio-economic communities, many have argued that it could easily be other factors that cause behavioural problems, and that to blame lead paint is simply an excuse.  Poor education and nutrition, high levels of street crime and easy availability of recreational drugs, and poor upbringing are all known to increase the chances of behavioral problems and criminal activity.  Gray’s own mother, for example, had problems with heroin. 

       However, higher levels of lead poisoning in poor areas could be explained quite simply: those living in poorer areas do not have the financial means to re-paint and care for their interiors in the same way that richer areas might.  Dietrich also negates the argument of other factors, by showing that not only did they control external factors as best as possible during their 30 year study, but also used brain imaging to show the lead poisoning leads to loss in the areas of the brain designated for controlling judgement and impulse, ultimately leading to diminished cognitive function.  Dietrich concludes that certainly, other factors will have an impact on a person’s life, and lead poisoning certainly does not reduce a person’s chances in life indefinitely, but that there is no doubt that lead poisoning is a driving factor in behavioral and criminal problems[9]

      Ultimately, we may never know what exactly causes people to behave in a certain way and rarely will it be down to one single factor.  One thing we can know for sure, however, is that lead poisoning definitely has a negative effect and the longer that we continue to let homes remain in these states, the worse that it is going to get. 


[1] Kim Dietrich, 2015, [radio broadcast], Here and Now, WBUR, May 7.  Available at

[2] Medline Plus, 2015, Lead Poisoning, [online].  Available at:, accessed 05/17/2015

[3] Terrence McCoy, 2015, Freddie Gray’s Life a Study on the Effects of Lead Paint on Poor Blacks, [online].  Available at, accessed 05/17/2015

[4] Arnold School of Public Health, 2007, Study Shoes Lead Poisoning Leads to Behavioral Problems in School Age, Urban Children, [online].  Available at:, accessed 05/17/2015

[5] Kim Dietrich, op cit.

[6] Terrence McCoy, op cit.

[7] Terrence McCoy, op cit.

[8] Terrence McCoy, op cit. 

[9] Kim Dietrich, op cit.

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Lead Poisoning and Criminal Behavior: Can there really be a link? by UrbanSculpt staff writer Victoria Found, MA is licensed under a Creative Commons Attribution 4.0 International License.
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