Information for Medical Professionals

Thank you for being here! There are a lot of myths about lead poisoning. Let’s discuss them, or just skip right to the resources and links that follow. (Note: This page focuses specifically on children)

On this page:
Common Myths
Statistics
Literature

 

Common Myths

1. Lead poisoning doesn’t happen anymore.
2. We haven’t seen a child with lead poisoning for years.
3. If a child isn’t showing symptoms then they haven’t been poisoned.
4. Blood lead levels below the notifiable level are normal and not concerning.
5. House painting is the only way kids are exposed to enough lead to be poisoned.
6. If a child isn’t eating paint chips, licking walls or has pica, then they’re fine.

Myth #1: Lead poisoning doesn’t happen anymore.

It is rare for children to die from lead poisoning now, that part is true. However, children are being exposed to lead every day. The biggest exposure sources are contaminated soil and dust from deteriorating/disturbed lead paint. Along with swallowing high-lead objects like fishing sinkers, these can cause acute lead poisoning. But there are myriad ways for kids to be exposed to lower levels of lead which can cause very damaging chronic lead exposure.

Myth #2: We haven’t seen a child with lead poisoning for years.

If you’ve assessed or treated children with any of these symptoms and not ordered a blood lead test, then it’s possible you HAVE seen a child with lead poisoning but didn’t know it at the time:
Constipation, diarrhea, abdominal pain, unexplained vomiting, loss of appetite, seizures, fatigue, irritability, behavioural issues, speech delay, hearing issues, developmental regressions, ADHD or autism symptoms

Myth #3: If a child isn’t showing symptoms, they haven’t been poisoned.

The vast majority of children with lead poisoning exhibit no symptoms at all. Even children with quite high acute poisoning often do not have symptoms, or the symptoms are easily written off as something else. The effects of lead poisoning often are not seen until years after the poisoning occurs, such as problems learning in school after the child was exposed as a young toddler.

Myth #4: Blood lead levels below the notifiable level are normal and not concerning.

There is no safe level of lead exposure. Studies have shown levels as low as 0.05 umol/L (1 ug/dL) to increase the likelihood of ADHD. The NZ notifiable level of 0.24 umol/L (5 ug/dL) is based on the US levels, which recently dropped further to 0.17 umol/L (3.5 ug/dL). These levels come from US population studies calculating the top 2.5% of childhood lead levels. They are NOT based on any measure of safety. Studies are continually finding that very low levels of lead exposure are damaging to children’s brains… such low levels that international health organisations have concluded that there’s no minimal blood lead level for which a safe threshold can be determined.

Myth #5: House painting is the only way kids are exposed to enough lead to be poisoned.

It takes only a microscopic amount of lead to poison a child – the equivalent of the weight of half a mosquito spread across a bedroom floor. While paint/dust and soil are definitely a child’s biggest exposure risks, there are dozens of other significant exposure risks as well. Even a minor kitchen renovation, a flooring upgrade, window replacement, or garden landscaping could cause acute poisoning. Even just a toddler living in a house built before 1950 without renovations is at risk of chronic lead poisoning due to exposure to lead dust in the carpet from previous renovations, leadlight windows, or contaminated soil that migrated indoors. Even just having a member of their whanau work in a lead-risk occupation such as building/renovating, painting, automotive work, metal smelting or recycling, or a whanau member who makes fishing sinkers, does leadlighting, or visits a shooting range could poison a child. Children have also been poisoned by regular use of crystal drinkware or vintage crockery, playing with vintage toys containing lead paint, having kohl applied to their eyes, being given ayurvedic medicine or other natural remedies such as bentonite clay.

Myth #6: If a child doesn’t eat paint chips, lick walls or have pica, then they’re fine.

This stereotype of lead poisoning is very unhelpful since children almost never actually eat paint chips to get lead poisoning. Lead paint dust is invisible and can be created in unexpected ways like a rubbing door frame that has exposed layers of lead paint under layers of modern paint, or a window that slides up and down, slowly sanding down the lead paint and covering the area with microscopic and invisible lead paint dust… or a ride-on toy knocking into a door frame causing a paint chip to fall to the floor, get stepped on and crushed into lead dust. A baby only needs to crawl under that window or door, pick up a toy and put some fingers in their mouth to be exposed to hazardous levels of lead. “Pica” or putting non-food objects in their mouth, is a normal developmental stage that makes babies more susceptible to lead exposure.

 

Statistics

NZ Statistics

The summary of lead exposure notifications is compiled by EHINZ. On average approximately 10 children in NZ receive a notifiable result annually. 

Comparison statisitics

The US state of Rhode Island (pop 1 million) has a programme of universally screening children’s blood annually from age 1-6. They find around 600 children with elevated blood levels annually. [click for reference]

Extrapolated equivalent children in NZ poisoned annually = 3000

The US state of California (pop 39 million) also has universal screening of children’s blood at ages 1 and 2, although reports say they miss a huge number of them. They found 5921 children with elevated blood levels (average 2019/2020). [click for reference]

Extrapolated equivalent children in NZ poisoned annually = 759

Data reported by UNICEF estimates that there are 47,673 lead-poisoned children in NZ right now. [click for reference]

 

Literature

NZ Ministry of Health, “Environmental Case Management of Lead-Exposed Persons” 2021

WHO guideline for clinical management of exposure to lead

Medscape “Pediatric Lead Toxicity” (need to create free account to access) 

ATSDR “Toxicological Profile for Lead”, U.S. CDC/Dept of Health and Human Services  (very detailed literature summary)

“Lead Poisoning” 2017 Learning tool for doctors

“50 Years of Research Shows there is No Safe Level of Childhood Lead Exposure” (Article summarising scientific and medical research about the significance of low-level lead poisoning)