7 things to know about lead exposure
Children around the world are being poisoned by lead on a massive and previously unrecognized scale.
Lead is a highly poisonous element that is responsible for nearly 1.5 per cent of annual global deaths – almost as many deaths as from HIV and AIDS, and more than from malaria.
Nearly a third of the world’s children – up to 800 million children – are affected by lead poisoning.
Lead affects a child’s developing brain, causing decreased intelligence, behavioural disorders and learning problems which can reduce potential earnings in adulthood. It also affects almost every organ in a child’s body, including the heart, lungs and kidneys.
The global magnitude of lead poisoning is only recently coming to light. Here are some findings from a groundbreaking report on lead exposure and its effects on children.
1. Lead is everywhere
Children can be exposed to lead in various places. It can be found in many consumer products, like water pipes, paint, food cans, spices, cosmetics and traditional medicines. Harder-to-see sources include air, water, food, toys and even the mud children play in. Lead is also used in industries such as mining and battery recycling.
Unborn children can also be exposed to lead through the exposure of their mothers, with adverse development impacts.
2. Lead exposure is hard to detect
One challenge in detecting childhood lead poisoning is that it is hard to observe and recognize.
At low to moderate levels of exposure, there are typically no symptoms or physical signs apparent to a clinician.
At moderate to high levels of exposure, children may complain of a variety of non-specific symptoms, such as headaches, insomnia, abdominal pain or discomfort, poor attention or loss of appetite.
The impacts of lead poisoning may result in indications of clumsiness, agitation or decreased activity and drowsiness, which can progress to vomiting, convulsions and coma in severe cases.
3. Lead affects children more than adults
The potential negative effects of lead are far greater for children than for adults.
A child’s brain grows fastest during the early years of childhood, when thousands of neural connections are made every second. Lead exposure can substantially interfere with this complex, important and delicate process.
Infants and young children absorb about 4-5 times more of the lead that enters their bodies than do adults.
The risk of ingesting lead-contaminated soils and dust is also higher, due to the way children play outdoors and because they are closer to the ground, especially when they are learning to walk and crawl.
4. Lead impacts growth outcomes
Lead exposure can create learning disabilities and challenges that affect children’s executive functioning, impulse control and levels of aggression. These conditions are often irreversible and, studies find, may impact the likelihood of learning and behavioral difficulties, violence, and crime in adulthood.
On a broader scale, all of these factors impact a country’s economic growth, prosperity and security. Accounting for the wide range of effects, a cost-benefit study in the United States found that there was an estimated benefit of $3.10 for every dollar spent in regulatory enforcement to reduce lead hazards.
5. Even a little means a lot
Lead is a potent neurotoxin that, even with low-level exposure, is associated with a reduction in IQ scores, shortened attention spans and potentially violent and even criminal behaviour later in life. Children under the age of 5 are at the greatest risk of suffering lifelong neurological, cognitive and physical damage, and even death, from lead poisoning.
Older children and adults may also suffer severe consequences from prolonged exposure to lead in food, water and the air they breathe, including increased risk of cardiovascular death and kidney damage later in life. The impact of lead on adults is so large that over 900,000 premature deaths per year are attributed to lead exposure.
6. Poorer children are at greater risk
It is often the poorest children who are the most severely affected by lead exposure. This is because they are likely to live in areas where exposure risks are higher, such as in places where informal lead-acid battery recycling and smelting operations are more common, near hazardous waste recycling facilities, or in homes that still contain lead in paint or pipes. These children are also more likely to live in areas with little access to health services that help monitor, treat and prevent exposure.
Most of the children impacted by lead live in Africa and Asia, but many are also affected in Central and South America and Eastern Europe.
Since the phase-out of leaded gasoline and gradually of lead-based paint, blood lead levels have declined dramatically in high-income countries. However, these levels for children and adults in low- and middle-income countries continue to be dangerously high.
7. Prevention is the best cure
Unfortunately, there is no known safe level of lead exposure, and lead poisoning is difficult to cure. Once lead has been in the body for a prolonged period of time, it is very difficult to remove, as it is frequently deposited in bones and teeth. By this point, much of the neurodevelopmental damage has already been done.
