兒童的鉛害之防止 要全面的 譬如說 無鉛汽油/油漆等等的注意防範
In a Contaminated World, Play Isn’t the Only Hazard
While the idea that a child has been playing with a Thomas the Tank Engine coated with lead-based paint may terrify parents, experts say the risk of being poisoned that way is actually not very high.
Lead in house paint, in dirt, in drinking water and in some rare but deadly folk medicines are all far more threatening or likely to cause brain damage — as are a few toys meant for older children or antique toys that are actually made of lead.
In an industrialized world, avoiding all environmental lead is impossible, and more than 300,000 children in the United States have levels high enough to cause concern, the Centers for Disease Control and Prevention estimates.
Still, there is no reason for lead to be in anything used by children, and there is no such thing as a “safe” level in a child, experts say. Treatment may be recommended as soon as blood levels exceed 10 micrograms of lead per deciliter of blood; anything over 100 micrograms is considered life-threatening.
Lead poisoning from house paint is the most common hazard. About 24 million homes have some layers of lead paint, and 4 million of those homes have young children living in them.
Fumes when paint is melted or dust when it is sanded can get deep into the lungs. Paint chips peeling off baseboards or radiators may be eaten. Even sliding up old windows or shutting doors creates dust that can get on the hands of babies and be licked off. Lead accumulates in the body, so an amount the size of a grain of salt can raise levels.
“If you’re renovating your 1925 farmhouse and your kids are there with you, that’s a much greater danger than anything in your toy box,” said Dr. Mary Jean Brown, chief of lead poisoning prevention at the Centers for Disease Control and Prevention in Atlanta.
Household water is another threat. Lead pipes in older homes have mostly been replaced, but leaded solder in old joints is still common. The best remedy, experts say, is to let a faucet run for a full minute, especially before adding water to anything for an infant, like powdered formula.
In the world of toys, choking on small parts is probably the greatest threat. The toys most likely to poison a child are not those decorated with lead paint, but those made of lead. Cheap vending machine jewelry may be partly or even mostly lead. A big sister’s toy ring or a big brother’s surfer pendant can kill a toddler.
Last year, a 4-year-old Minnesota boy died with blood levels of 180 micrograms per deciliter after swallowing a heart-shaped charm that came with a pair of children’s shoes. It stayed in his stomach for several days, where acid ate away at it. A 5-year-old girl who ate lead pellets from an ankle weight was saved only because she was seen eating them, according to a C.D.C. report — but her blood level soared to 79 micrograms even as she was being treated.
Without a lab test, it is impossible to be sure a trinket contains lead, but experts suggest caution.
“If it’s cheap and heavy, if it’s brightly colored and imported, I’m suspicious,” Dr. Brown said.
Folk remedies for upset stomach, including azarcon and greta among Hispanics, ba-baw-san among Chinese or ghasard among Indians, may contain large amounts of lead. So may the Middle Eastern cosmetic called kohl, so children should not be allowed to play dress-up with it.
It is impossible to accurately measure how much danger any painted toy presents, scientists say. Not all paints have lead; it seems more common in reds and yellows. Chewing a toy is more dangerous than licking it, and so on.
Children’s blood lead levels should be routinely tested by a doctor twice during infancy, plus any time exposure is suspected. Mildly elevated blood lead levels are treated by removing the source and making sure the child gets a healthy diet, including iron and calcium.
If a child has swallowed a piece of lead, doctors will go after it by flushing the digestive system or emergency surgery.
For dangerously high blood levels, treatment is chelation therapy, which itself is risky and can be painful. It cannot reverse organ damage, nor is it clear that the treatment can raise I.Q.’s again.
Fears must be kept in perspective, experts say. Lead paint on toys and children’s furniture was not banned in the United States until 1978, so most parents probably grew up with greater risks than their own children face.
Four decades ago, the median blood lead level in preschool children was 15 micrograms, and only levels over 60 were considered toxic. Average American levels have plummeted since then, primarily because of bans on leaded gas and house paint.