How much lead is too much?

Lead is a soft, naturally occurring metal used in many products. It can be found in contaminated soil or water, old paint, inexpensive jewelry and other consumer items, such as blinds and leaded crystal.

Too much exposure to the metal can cause serious illness. In young children, it can impair neurological development.

In its lead strategy, Health Canada identifies four categories of consumer products that children are likely to come into contact with and ingest in significant quantities, some of which may contain lead:

• Products intended to be or likely to be placed in or near the mouth, such as pacifiers, baby bottle nipples, crib toys, mouthpieces of musical instruments.
• Children's equipment, furniture, toys and other items intended for use by a child in learning or play, such as strollers and high chairs.
• Products intended for use in preparing, serving or storing food or beverages, such as cutlery, tableware and cooking utensils.
• Consumer products intended to be or likely to be melted or burned in enclosed spaces, such as candles and fuel for indoor lanterns.

When is lead poisonous to children?

Children are most vulnerable to lead exposure because they absorb it more easily than adults. Due to their low body weight, any amount of lead is more dangerous to children than it would be to adults. Children aged six and under are particularly vulnerable to lead contamination because of their instinct to put objects in their mouth.

The ingestion of about one mg a day on a continued basis can severely affect children but such exposure rarely comes from infrequent handling of toys made or coated with lead, according to McGill University chemistry professor Joe Schwartz.

Toys coated with lead paint can be dangerous when the paint is ingested. Children are not at risk from simply playing with toys made or painted with lead, even if they mouth them once or twice. However, parents should have their children's blood lead levels tested if they notice the paint on their toys has been stripped off.

Health Canada considers lead levels in your blood below 10 micrograms per decilitre safe. If levels rise above 25, doctors will monitor them. At about 40, treatment becomes necessary to reduce the lead load in the body.

However, in November 2007, researchers at Cornell University released a study that found that kids exposed to"safe" lead levels had reduced IQ scores. The researchers called for stricter regulations. Less than a year later, the U.S. passed legislation banning lead from children's toys, imposing the toughest standard in the world. The law prohibits lead, beyond minute levels, in products for children 12 or younger. Lead paint was a major factor in the recall of 45 million toys and children's items in 2007. Most of those toys were imported from China.

A British study conducted by researchers at the University of Bristol, found that children with blood lead levels between two and five micrograms per decilitre performed significantly better in their Scholastic Aptitude Tests than children whose levels were above five micrograms per deciliter.

The World Health Organization has set 10 micrograms per deciliter as the international acceptable level of lead in the blood. The British researchers say that level should be cut in half.

Falling lead levels

Canada currently follows the WHO's standard, but Health Canada has updated itsLead Risk Reduction Strategy.

In August 2010, Health Canada and Statistics Canada said thelevel of lead in Canadians' blood has dropped dramatically in 30 years.

Lead was detected in 100 per cent of the population surveyed.

Average lead concentration for people aged six to 79 measured by the survey between 2007 and 2009 was about one-third of the concentration measured in the 1978-79 Canada Health Survey for the same age group.

In 1978-79, about 27 per cent of Canadians aged six to 79 had blood lead concentrations at or above the intervention level, compared with less than one per cent from 2007-09.

The decline reflects the removal of major sources of lead from the environment, according to the report.

Since the 1970s, lead has no longer been added to automotive gasoline or used as solder in food cans, and lead limits in paint have been reduced.

Lead continues to be used in the refining and manufacturing of products such as lead acid car batteries and electronic equipment.

How does lead affect young children?

Lead accumulation in the body usually occurs through gradual exposure. However, even small amounts can affect children.

Most who have mild lead poisoning do not look or act ill. Symptoms can be confused with general stomachaches, crankiness, headaches or loss of appetite. Learning problems are often some of the first signs to appear, including an inability to process new information and forgetfulness.

High amounts of lead can harm the nervous system, kidneys and other major organs. Anemia, a decline in red blood cells, can occur, as well as damage to the nervous system that may impair mental function. At worst, lead poisoning can cause seizures or death.

The biggest danger lead poisoning poses to young children is brain damage. This can result in lower IQ levels, hyperactivity, developmental delays and aggression. Although brain damage is irreversible, blood lead levels can be lowered to prevent further damage.

What you can do to protect your children

• Avoid purchasing toys from vending machines. In 2004, 150 million pieces of children's jewelry in the U.S. were recalled from vending machines.
• Avoid toys that have small parts that could be swallowed, especially if the parts are metal or metallic.
• Avoid glossy fake pearls that may be coloured with lead paint.
• Test suspicious jewelry. You can buy home lead-testing kits at many hardware and paint stores.
• If you're really concerned, get your child tested, as this is the only sure way to know how much lead your child has been exposed to.

How can you tell if your child's toys contain lead?

While it's difficult to tell if a product contains lead just by looking at it, here are a few tips that may help you identify it:

• Dull, grey-looking metal.
• Pieces that seem heavy for their size.
• If you rub a piece of jewelry against a sheet of paper and it leaves a grey line, it's probably made of lead.
• Bright colours, especially orange and red.
• Soft plastics, as lead is used as a stabilizer to help keep the plastic soft.

Health Canada tests toys and jewelry suspected of lead contaminationandencourages consumers to contact the National Capital Region Consumer Product Safety Bureau if they have concerns.