Is Cadmium the New Lead?

Mike Magee MD

The report began “Could cadmium be the new lead?” and was illustrated with four “Shrek glasses”, part of a promotional McDonald’s campaign. (1) Now that caught my eye because I’ve been following lead and fast food for awhile. In 2005 I first reported on the checkered history of lead in America. (2) It wasn’t a pretty picture. And my piece on “corn-fed America” led right to McDonald’s golden arches and poverty ladden childhood obesity (3)

In the United States, we have been fast to build overlapping, redundant, reactive, and non-integrated health systems, but slow to advance the cause of health in a reliable and verifiably equitable way. Lead poisoning is an excellent case that well illustrates this point.(4) In 1908, an Australian scientist first recognized an epidemic of lead poisoning in children. It took European nations just one year to make a connection with lead-based paints and ban their use. Australians verified the connection in medical journals in 1912. But in the United States, it would take nearly 70 more years to ban lead in paints, due mostly to the effective lobbying action of the Lead Industries Association.(4) As the group’s president boasted in 1984, “Our victories have been in the deferral of implementation of certain regulations.” (5)

Once the weight of the facts and the actions of other nations drove regulatory bodies to action, those actions were still timed and incremental. Take, for example, the definition of lead poisoning in the United States. In 1970, a blood lead level of greater than 60 micrograms per deciliter made the diagnosis. One year later, the level was lowered to 40. It would take 7 more years to drop it to 25. Not until 1991 did we reach the current level of 10 micrograms per deciliter as the definition of lead poisoning.(4,6)

Large portions of the U.S. population benefited from new regulations that banned lead paint and progressively decreased the amount of lead in our gasoline. In 1970, 88 percent of all U.S. children under age 6 had blood lead levels above 10 micrograms per deciliter. By 1991, only 5 percent.(7,8) Even so, significant numbers of children are still affected. A study from 1999 to 2001 found that 430,000 kids, or 2.2 percent of under age 6 population had lead poisoning.(9) The numbers were higher among poor kids with rates topping 6 percent in one Medicaid study. Also, lack of proper follow-up post-diagnosis is extremely common. A study published in 2005 found that out of about 3,600 Medicaid-enrolled children in Michigan with lead poisoning, 46 percent did not receive appropriate follow-up testing.(10) By the way, that same population is overweighted when it comes to drawing on McDonald’s as a source of it’s daily nutrition.

And then there’s cadmium. Who knew? First of all, what is it and where does it come from? It’s a soft whitish metal with a blue hue first discovered in 1817 by German chemist Friedrich Stromeyer while working with zinc. (11) Once isolated as an impurity of that substance, it eventually received its own atomic number, 48, and fell into the period table in close association with another toxic metal, mercury. (12) For its first 100 years, Germany was it’s major producer. By the 1930’s however it became deeply entrenched in the industrial revolution once it’s anti-corrosive properities when plated on copper and steel became evident. By the 1950’s, 60% of US consumption of cadmium was for this purpose. Some 24% was used in paint pigments – more on that and the Shrek glasses in a moment. (13) By the 1980’s, it had found a new purpose as a stabilizer in plastics. But at the same time, growing reports of kidney toxicity and the labelling of cadmium as a carcinogen cut into it’s popularity. In fact, within the last 25 years, consumption has dropped 10 fold with 80% of its use today being in nickel-cadmium rechargeable batteries. (14)

As with lead, the Europeans are ahead of the US in sending up alarms, having banned cadmium use in all electronics in 2004, and currently considering curtailing its use in batteries.(15) In the US “hands off” culture, we rely more heavily on information campaigns and market driven voluntary recalls. The problem with the former is that product lobbyists tend to dampen or confuse the flow of accurate information. For example, did you know that the single largest source of cadmium exposure in the general population today is cigarette smoke? Neither did I. Smokers have cadmium concentrations in their blood that are five times higher than non-smokers. (16)

As for voluntary recalls, we’ve actually had two big ones for cadmium in 2010. The first was for children’s jewelry from a range of national outlets including 55,000 items from Walmart stores.(1,17) It came in the wake of a US Consumer Product Safety Commission investigation of 103 items demonstrating that 12% of the children’s jewelry pieces contained greater than 10% cadmium – and one tipped the scale with 91% cadmium.(18) Yikes!

And finally, the McDonald’s Sherk recall – 12 million glasses produced in the US by a glass manufacturer based in France.(19) Let’s take a moment to look at cadmium in artists paints. Cadmium was first used by artists in the 1840’s, notably by Claude Monet. By 1920, use was widespread providing “unequaled hues in the yellow to deep red range, in terms of brightness and lightfastness”.(20) Where cadmium paints really excel is in high heat applications as with painting on glass.

Even a few years ago this recall probably would never have occurred. You see, it wasn’t a government agency that sounded the alarm. It was a few everyday consumers, less inclined to give corporations, in the wake of Enron, BP and others, the benfit of the doubt. Using a hand-held X-ray flourescence analyzer, a Los Angeles mother of a 7 year old tested the glasses at home and got a positive reading for cadmium. She chatted online with a few others with devices, and before long the glasses were in the hands of Ohio chemist Jeff Weidenhamer. He scrapped off a bit of Shrek’s green paint and found cadmium levels of up to 956 parts per million. The Federal limit for cadmium in paints on toys is 75 parts per million.(1)

So is cadmium the new lead? Well it’s a heavy metal with known toxicity. So the simple answer is “yes”. But if you stop there, you’re missing the bigger message here. The U.S. government and her U.S. based multi-national corporations have long favored a laissez-faire approach to regulation and restrictive guidelines. Compared to other developed nations, we have been content historically to “trust the market” and be a follower rather then a leader when it came to environmental health and safety concerns. Corporations have pledged committment to consumer information and transparency with one hand, while quietly employing legions of lobbyists and public affairs communication teams to counter-detail behind the scenes with the other hand. Consumers in turn, with little confidence or trust in the unholy marriage of goverment and corporations, are not only empowered but now fully engaged and connected to activists, bloggers, academics and influentials who know how to “press the buttons”.

Is cadmium the new lead? Yes, but it is also the signal of the emergence of a new type of consumer – one with little patience and a lot of teeth.

For Health Commentary, I’m Mike Magee.

References:

1. Neumann W. McDonald’s To Recall Glasses, Citing Cadmium. New York Times. June 5, 2010. B1. http://www.nytimes.com/2010/06/05/business/05recall.html

2. Magee M. The Story of Lead Poisoning. June 24, 2005. Health Politics.My Blog http://bit.ly/dAFjj0

3. Magee M. Corn Fed America. Health Politics.My Blog http://bit.ly/a1wo1h

4. Lanphear BP. Childhood lead poisoning prevention: too little, too late. JAMA. 2005;293:2274- 2276. http://jama.ama-assn.org/cgi/content/extract/293/18/2274

5. Reich P. The Hour of Lead: A Brief History of Lead Poisoning in the United States. Washington, DC: Environmental Defense Fund;1992.http://www.edf.org/documents/246_The%20Hour%20of%20Lead.htm

6. Centers for Disease Control. Preventing Lead Poisoning in Young Children: A Statement by the Centers for Disease Control. Atlanta, Ga. US Dept of Health and Human Services; 1991. http://www.cdc.gov/nceh/lead/publications/books/plpyc/contents.htm

7. Annest JL, Pirkle JL, Makuc D, Neese JW, Bayse DD, Kovar MG. Chronological trend in blood lead levels between 1976 and 1980. NEJM. 1979;300:689-695. http://bit.ly/9YVUFo

8. Pirkle JL, Kaufmann RB, Brody DJ, Hickman T, Gunder EW, Paschal DC. Exposure of the U.S. population to lead, 1991-1994. Environ Health Perspect. 1998;106:145-150. http://www.neurology.org/cgi/content/abstract/67/9/1556

9. Meyer PA, Pivetz T, Dignam TA, Homa DM, Schoonover J, Brody D. Surveillance for elevated blood lead levels among children – United States, 1997-2000. MMWR. 2003;52:1-21.http://bit.ly/8XSM2Q

10. Kemper AR, Cohn LS, Fant DE, Dombkowski DJ, Hudson SR. Follow-up testing among children with elevated screening blood lead levels. JAMA. 2005;293:2232-2237. http://www.health.state.mn.us/divs/eh/lead/reports/legislative/2007fullrep.pdf

11. Hermann (1818). “Noch ein schreiben über das neue Metall(Another letter about the new metal)”. Annalen der Physik 59: 113.

12. Cotton, F. Albert Advanced Inorganic Chemistry, 6th Edition, John Wiley and Sons (1999) Chapter 16: Survey of Transition-Metal Chemistry p. 633 ISBN 0471199575 http://www.goldenpaints.com/justpaint/jp4article2.php

13. Lansche, Arnold M.. “Minerals Yearbook 1956: Cadmium”. United States Geological Survey.

14. USGS Commodity Report cadmium”. United States Geological Survey.

15. European Directive on restriction of hazardous substances in electrical and electronic equipment. January 27, 2003. http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2003:037:0019:0023:EN:PDF

16. Friberg, L. (1983). “Cadmium”. Annual Review of Public Health 4: 367–367. doi:10.1146/annurev.pu.04.050183.002055.

17. “FAF Inc. Recalls Children’s Necklaces Sold Exclusively at Walmart Stores Due to High Levels of Cadmium”. U.S. Consumer Product Safety Commission. 2010-01-29. http://www.cpsc.gov/cpscpub/prerel/prhtml10/10131.html

18. U.S. to Develop Safety Standards for Toxic Metals”. Business Week. 2010-01-12.http://bit.ly/b4q9pF

19. http://uk.arc-intl.com/home.aspx

20. Will cadmium always be on the artist’s palette? Just Paint. Issue 4, 1996. http://www.goldenpaints.com/justpaint/jp4article2.php