So what’s the deal with lead and slow cookers? Here’s what I found:
Most slow cookers sold in the U.S. probably do not contain or leach detectable amounts of lead (1). Keep that in mind while reading the rest of this, so you don’t panic.
Because some – possibly a significant number – probably do contain detectable lead, and this lead has been found to leach into food (1).
Wrong: The current medical consensus is that there is no safe level of lead, especially for children, who absorb a much higher proportion of it than adults and are more vulnerable to its effects, serious neurological damage being chief on a dreadful laundry list affecting every organ. Lead accumulates in the body, so small exposures can add up gradually over the years (2).
In the last decade researchers have found that much of the harm done to children occurs at extremely low levels of exposure. Nor is it great to expose adults to low levels of lead, especially pregnant women (2). It appears that FDA standards are out of date.
Yep, crock pots that leach potentially harmful — cumulatively if not immediately – amounts of lead can still be legally sold. They can even declare themselves “lead-free.”
The way slow cookers are actually used means they could well leach more than standard testing might suggest. Time, temperature, and acidity greatly increase leaching, especially the latter two (4). Crock pots are used for 8 to 12 hours, at far above the standard leach-test temperature of 80 degrees F, and often with acidic ingredients like tomatoes, vinegar, wine, and citrus. (And I was telling people to make bone broth in them!)
Currently available over-the-counter test kits are NOT sensitive enough to detect levels we’re talking about here. You’d have to go to a private lab where they have X-ray fluorescent guns and spectrometers and can do an ASTM C738-94 extraction test and whatnot (1). And even if your pot is not leaching now, what about down the road, with use and wear?
So it’s a no-brainer, right? Drop the crock pot! Who needs more lead than we’re already getting? End of story.
Oh, but you don’t know me, do you. If you did, you’d know that I’m going to give you the counterargument. Because, yes, there is one to be made. Or at least a qualification. And if you do know me, then you know that if there’s an argument or a qualification to be made I’m gonna make it, whether anyone wants to hear it or not.
This mental rigidity could well be because I’m one of those people born between 1945 and 1971, who, thanks to leaded gasoline, have astronomically higher body levels of lead than people born after that period, levels 300 to 1000 times higher pre-Columbian indigenous people (5).
It may also be because, dammit, I love my crock pot. That’s right. I couldn’t let go. And because I couldn’t let go, I waded in deeper.
So next up, more about lead & heavy metals in crock pots and the world:
- Why and how you might still use a slow cooker, and the safest way to buy and use one. Everything thought you didn’t need to know about California Proposition 65 and porcelain enamel coatings.
- Crock pot alternatives. Because you still gotta slow cook. (Hint: cast iron, enameled if you can afford it, non-enameled if you can’t; people slow cooked before crockpot, and once again a tradition has it right).
- Perspective on lead & heavy metals that will once again lead you to the inexorable conclusion that good nutrition is the best defense against the toxic soup of continuous multiple low-level exposures in which we are today condemned to swim, whether we get rid of our crock pots [whimper!] or not.
1. Most slow cookers sold in the U.S. probably do not contain lead … [but] some – possibly a significant number – probably do … and this lead has been found to leach into food.”
I’m basing these carefully qualified assertions on two sources. The first is investigative reporter Bill Gephardt’s remarkable series on lead in foodware, aired on KUTV in Salt Lake City in December of 2007. It’s a story that bears retelling, especially as it’s no longer available on the web.
Following the alarming results of his initial investigations into lead in dishes, Gephardt, prompted by a viewer who alerted him to high levels of lead found in her crock pot at a fairgrounds test, took a small random sample of ten or so slow cookers to a private lab (admittedly a small sample, but then investigative reporters don’t have FDA budgets).
There he found at least two crock pots contained measurable amounts of lead, suggesting in a preliminary sort of way that something like 20 percent of the product out there might have detectable lead in it – and of course that something like 80 percent might not.
Gephardt then took the viewer’s crock pot to another private lab to undergo the standard FDA test for leaching. The result was leachable lead at 0.85 parts per million. Perfectly legal by FDA standards of 1.0 ppm for “large ceramic hollowware” (http://www.fda.gov/ICECI/ComplianceManuals/CompliancePolicyGuidanceManual/ucm074516.htm). But unacceptable by recent medical standards (see below).
Though Gephardt’s samples weren’t big enough to be conclusive, they were big enough to be suggestive. But no one is going to undertake massive testing or modifying of a product containing levels the FDA already considers acceptable.
In the best of worlds, the FDA would have tightened its standards after 2005, by which time medical research had established the need to do so. To its credit, the agency has done so a number of times in the past, keeping up with the increasingly worrisome findings on lead since the 1930s. But this isn’t the best of worlds, not these days.
So now you know why my terms are so qualified – “probably,” “possibly,” “something like.” In a world of as-long-as-inadequate-government-standards-are-met-no-one-has-any-idea-what’s-in-there-and-no-one-has-the-money-and-resources-to-systematically-look, one lone reporter is all I’ve got.
Gephardt’s series inspired Utah Representative Jim Matheson to seek U.S. labeling legislation. In 2009 Matheson managed to get some labeling for ceramic foodware into federal law: “This product is made with lead-based glaze consistent with Food and Drug Administration (FDA) guidelines for such lead.” No doubt the mild-to-the-point-of-misleading “warning,” which sounds more like a reassurance, that emerged from the legislative sausage-making does not honor the congressman’s original intentions (http://matheson.house.gov/index.cfm?sectionid=49.12&itemid=182).
I am indebted to the blogs “Insightful Nana” (http://insightfulnana.com/home-garden/housekeeping-home-garden/lead-poisoning-and-crock-pots/html) and “Green Fertility,” (http://greenfertility.blogspot.com/2008/03/lead-in-rival-crockpots.html), and to natmommy.com of the Mothering.com community (http://www.mothering.com/community/t/852699/crock-pots-and-lead/20), for bringing Gephardt’s crock-pot segment to my attention. The latter two posted excerpts of the KUTV web text for Gephardt’s original stories, which are no longer posted on the station’s website or elsewhere and would otherwise have been lost to anyone not willing or able to pay a private service for video clips or a subscription database.
Because I had no original copy, I emailed Gephardt the excerpts of the text; he confirmed their accuracy, for which I thank him here. Gephardt is still steamed about the lack of labeling in Utah and the rest of the U.S. except California. “Let people eat chunks of lead if they want to. But they should know it’s there,” he said, adding, “You just don’t have to use lead in these products. It’s micropennies cheaper.” As for FDA standards that legalize medically unacceptable lead levels, he had a choice word not printable in a family blog.
My second “source” is more like a suspicion: the simple inference you can make from the gap between current medical consensus (see below) and the current regulatory standards (see below), plus the fact that food is heated in crock pots for long periods of time, often under acidic conditions. And while the standard leach test is a longer period (24 hours), it is only done at 80 degrees F, while a crock pot gets three times as hot.
2. Current medical consensus is that harm to children from lead occurs at very low blood levels, well below the previously defined (1991) CDC “level of concern” of 10 micrograms per deciliter. Indeed, a great deal of the damage done by lead appears to happen at below 10 micrograms/dL, starting measurably at 1 microgram/dL, with no safe level found.
Levin, Ronnie, et al. “Lead Exposures in U.S. Children, 2008: Implications for Prevention,” Environmental Health Perspectives, 2008 October; 116(10): 1285–1293. Published online 2008 May 19. doi: 10.1289/ehp.11241, http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2569084/
Bellinger, David, C., Harvard Medical School. “Very low lead exposures and children’s neurodevelopment,” Current Opinion in Pediatrics: April 2008 – Volume 20 – Issue 2 – p 172-177, http://journals.lww.com/co-pediatrics/pages/articleviewer.aspx?year=2008&issue=04000&article=00013&type=abstract ;
Brown, Mary, Centers for Disease Control. “Interpreting and Managing Blood Lead Levels <10 micrograms/dL in Children and Reducing Childhood Exposures to Lead; Recommendations of CDC’s Advisory Committee on Childhood Lead Poisoning Prevention,” CDC, Nov. 2, 2007, http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5608a1.htm ;
Brody, Jane E. “Personal Health; Even Low Lead Levels Pose Perils for Children,” New York Times, Aug. 5, 2003
Kosnett, Michael J., University of Colorado, Denver. “Health Effects of Low Dose Lead Exposure in Adults and Children, and Preventable Risk Posed by the Consumption of Game Meat Harvested With Lead Ammunition,” http://www.peregrinefund.org/subsites/conference-lead/PDF/0103%20Kosnett.pdf. This article is useful because it looks at levels and vectors comparable to the FDA maximum allowable leachable lead level for crock pots.
For a great overview of the above findings and much, much more, see the Franklin Institute’s website: http://www.fi.edu/learn/brain/metals.html
3. The FDA maximum allowable leachable lead limit for “large ceramic hollowware” is 1.0 ppm. See “CPG Sec. 545.450 Pottery (Ceramics); Import and Domestic – Lead Contamination,” issued 10/1/80; revised 4/16/92, 12/12/95 (60 FR 63721), 5/2005; updated 11/29/05: http://www.fda.gov/ICECI/ComplianceManuals/CompliancePolicyGuidanceManual/ucm074516.htm
Detection limits of the test used to establish regulatory compliance: http://www.fda.gov/Food/ScienceResearch/LaboratoryMethods/ElementalAnalysisManualEAM/ucm221685.htm
4. Time, temperature, and acidity: Hight, S. C., et al. “Lead and Cadmium Release Under Conditions of Consumer Use: FDA Experiments With Cookware, Glass Tumblers, Lead Crystal Baby Bottles, And Ceramic Mugs,” Ceramic Transactions, Vol. 61 , pp. 11-22, 1995: http://md1.csa.com/partners/viewrecord.php?requester=gs&collection=TRD&recid=7708035CWC&q=FDA+leachable+foodware&uid=791387631&setcookie=yes
A high percentage of the lead leaches in a 24-hour contact period does so in the first few minutes, so length of cooking is a perhaps a relatively insignficant factor. However, temperature and acidity are highly significant factors, especially temperature – crock pot cooking may be low temperature for cooking, but the test uses room temperature (80 degrees F). See:
“Policy Statement Concerning Lead Leaching From Glass Tableware Into Foodstuffs,” Partial Agreement in the Social and Health Field, Council of Europe Public Health Committee: http://www.coe.int/t/e/social_cohesion/soc-sp/public_health/food_contact/PS%20E%20LEAD%20LEACHING%20VERSION%201.pdf
5. Historic blood levels: Issacs, Steven, “Where Public Good Prevailed,” The American Prospect, July 19, 2001, http://prospect.org/article/where-public-good-prevailed and The Franklin Institute website resource page, http://www.fi.edu/learn/brain/metals.html.