Historic legacy of lead pollution persists despite regulatory efforts

February 16, 2013

Efforts to reduce lead pollution have paid off in many ways, yet the problem persists and will probably continue to affect the health of people and animals well into the future, according to experts speaking at the annual meeting of the American Association for the Advancement of Science (AAAS) in Boston.

"Things have substantially improved with the virtual elimination of leaded gasoline, restrictions on , and other efforts to limit releases of industrial lead into the environment. But the historic legacy of lead pollution persists, and new inputs of industrial lead are adding to it," said A. Russell Flegal, professor of environmental toxicology at the University of California, Santa Cruz.

The good news, he said, is that atmospheric lead concentrations in the United States have fallen by 89 percent in the past three decades, and average blood lead levels in U.S. children have shown a corresponding decline, from 15 micrograms per deciliter (ug/dL) in 1976 to 1.3 ug/dL in 2008.

The bad news is that blood lead levels are still about 100 times higher than the natural background level, and there is no known threshold for lead toxicity. In other words, even tiny amounts of lead in the body can be harmful.

Lead pollution is a 5,000-year-old problem, Flegal said, citing elevated in Chinese deposited during the Bronze Age. Recent records from U.S. lake sediments show decreases in lead pollution since the phasing out of leaded gasoline began in the 1970s. But industrial activities around the globe continue to release more lead into the environment. Major sources of lead emissions include the burning of coal, especially in developing countries such as China and India. Lead from these sources spreads around the globe, so that environmental lead contamination can be detected even in "pristine" environments such as the Arctic and the , Flegal said.

In addition, consumer products contaminated with lead continue to enter the U.S. from other countries through global trade. These include some foods, health products, and children's toys. Just last year, U.S. customs officials seized 1,400 Halloween pirate costumes imported from China that contained 11 times the allowable level of lead.

Unlike organic pollutants, lead never degrades. To illustrate the persistence of lead in the environment, Flegal cites a 2005 study showing that 90 percent of the current atmospheric lead pollution in the Los Angeles basin originally came from . Lead particles continue to be deposited on the ground and resuspended into the air decades after their original source was eliminated. Studies by Flegal and others also show that forest fires in California remobilize that was deposited in soils decades ago.

"It will take decades to centuries to purge these historic depositions from the environment," Flegal said.

Explore further: Leaded gas exposure linked to later violence: study

Related Stories

Children's lead poisoning drops

May 28, 2009

(PhysOrg.com) -- In 2007, 416 children were reported to have elevated blood lead levels in Los Angeles County, a dramatic improvement from 10 years earlier, when fewer children were tested but 1,184 reports of children with ...

UN: Leaded fuel to be gone by 2013

October 28, 2011

(AP) -- Leaded gasoline, once so widespread it was sold at U.S. pumps as "regular" fuel, is expected to be eradicated globally within two years, the United Nations Environment Program announced Thursday.

Lead from gasoline discovered in Indian Ocean

June 27, 2012

Since the 1970s, leaded gasoline has been slowly phased out worldwide, as studies have shown that lead can cause neurological and cardiovascular damage and degrade vehicles’ catalytic converters. Today, 185 countries ...

Recommended for you

Scientists determine source of world's largest mud eruption

October 17, 2017

On May 29, 2006, mud started erupting from several sites on the Indonesian island of Java. Boiling mud, water, rocks and gas poured from newly-created vents in the ground, burying entire towns and compelling many Indonesians ...


Adjust slider to filter visible comments by rank

Display comments: newest first

1.9 / 5 (9) Feb 16, 2013
It is sad for the hundreds of millions of poisoned Americans that Republicans delayed the removal of lead from gasoline for so many decades after it was found to be poisonous and a neuro-toxin.

Some think that the reason why American's have become so stupid is a direct result of the lead exposure that American Capitalism created and Republicans protected.
3.3 / 5 (7) Feb 16, 2013
Vendicar overlooks many technical problems that plagued the issue and continue to wreak havoc: The most common octane booster, MTBE, is also a poison. Instead of an air soluble poison, we have a water soluble poison. MTBE is also not as good a substitute as TetraEthyl Lead was for boosting octane performance in fuel. To this day, Aviation gasoline still uses TEL because until recently, there were no acceptable alternatives that will provide the detonation margins required for higher performance gasoline aircraft engines to perform as designed.

Vendicar's post is a cheap shot toward party politics while there were and are serious technical engineering problems that had not been properly resolved. Thankfully, most readers here have learned over the years to expect such cheap behavior from Vendicar.
2 / 5 (8) Feb 16, 2013
ab3a ignores the muscle cars from the 50s and 60s on highways. Somehow they continue to move despite the lack of lead
2 / 5 (8) Feb 16, 2013
ab3a ignores the fact that the European states were using lead free gasoline long before Republicans in the U.S. dropped their obsessive support for the ongoing lead poisoning of the American people.

"Vendicar overlooks many technical problems that plagued the issue and continue to wreak havoc:"- ab3a

2.1 / 5 (7) Feb 16, 2013
European states which banned using leaded fuel in automobiles before the USA did: Austria (1989), Germany (1988), Sweden (1992).
The EU as a whole didn't stop until 2000, and the UK still has it available.

Also, California banned TEL in 1992, under a Republican governor- Pete Wilson. In 1967, Republican Ronald Regan signed the law creating the California Air Resource Board.

Damn those Republicans always doing bad things!
2 / 5 (4) Feb 16, 2013
Americans should thank their lucky stars that Liberals in California started America on a path to outlawing lead in gasoline.

Researchers link toxic element to violent behavior

5 / 5 (1) Feb 17, 2013
Vendicar overlooks the very well documented case of aviation gasoline.

Kochevnic: Muscle cars rarely spend a few seconds at full throttle at a time and then they spend most of their run at no more than 15% capacity. Aircraft engines stay at full throttle for several MINUTES and then run at 75% power continuously for hour after hour. These instances are not comparable.

Vendicar presumes that all environmental improvements came from one party. It's never that simple my party hack friend: For example: who signed a bill requiring higher quality diesel fuel for the US? It was none other than that dastardly Bush 43. Who created the EPA in the first place? It was none other than that evil Richard Nixon!

Both parties have histories of environmental progress. Both have histories of environmental ignorance. Acting as if all goodness flows from one place shows that you are very gullible.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.