For the first time, FDA has provided guidance on how to evaluate whether metal cookware is prohibited due to lead leaching into food.
As part of an investigation to find the source of elevated blood lead levels in some refugee children, the Hazardous Waste Management Program in King County, Washington [1] encountered high lead levels in certain imported [2] aluminum cookware, including pressure cookers and pots & pans. The program attempted to bring this to FDA’s attention in late 2019, and submitted a formal product report to FDA in October 2021, after several attempts to contact an FDA representative directly.
In May 2022, the Program published a journal article about its findings; a year later, staff emailed FDA again seeking guidance. On June 1, 2023, FDA responded with a letter [PDF, 166KB] providing a method (see below) to evaluate lead in metal cookware. The agency also said:
There is no safe level of exposure to lead. Through its Closer to Zero program, FDA has committed to reducing children’s exposure to lead. That effort is primarily focused on lead as a contaminant in food and not in food contact materials containing lead that can leach into food or water. In many cases, the lead may be added, such as:
In December 2020, EDF and 11 other organizations filed a citizen petition with FDA documenting the problem and asking the agency to prohibit the intentional addition of lead, and to tighten the limits on contaminants more generally. Supporting comments from more than 50 organizations provided additional documentation. FDA has not yet made a decision on that petition.
In providing guidance for evaluating metal cookware, FDA modified an existing method “ [PDF, 1.35MB] designed for silicate-based materials, such as earthenware, ceramicware, and lead crystal” used as foodware. To account for high temperatures in cookware, the agency said to boil vinegar (4% acetic acid) in the cookware for two hours, and then let it sit for a total of 24 hours and analyze the liquid for measurable amounts of lead.
FDA noted that the method has a measurable limit of 50 to 100 ppb for lead and that other methods have lower limits that “may be preferable to further reduce the risk of lead leaching into food from cookware.”
FDA’s letter provides long-overdue guidance on how to evaluate lead in metal cookware. The information will help industry comply with its responsibilities not to sell adulterated cookware. It will be particularly helpful to state and local health departments that are on the front lines of protecting children from lead, especially as they investigate cases of children with elevated blood levels.
We applaud both the Hazardous Waste Management Program and the FDA, the former for its investigations and outreach to the FDA, and the latter for its clear response. Strengthening the critical lines of communication among public health agencies will help protect children and make food, cosmetics, and other products safer for all.
However, FDA’s letter raises a number of questions that should be addressed:
EDF and our allies focused on protecting children from harmful lead exposure will continue to push for FDA to act on lead, including considering our options to force the agency to finally address long-standing problems with lead in food contact materials raised by the citizen petition. We filed a FOIA request seeking the agency’s documents and other communications regarding lead in food contact materials, which may shed some light. We will also work with health departments and industry to find ways to drive lead exposure closer to zero.
[1] The Program is a public partnership consisting of five partners: Public Health – Seattle & King County, King County Solid Waste Division, King County Water and Land Resources Division, Seattle Public Utilities and Sound Cities Association.
[2] High levels initially found in cookware from Afghanistan and later in products imported from other countries including India, China, Columbia, Pakistan and elsewhere according to the Program.
[3] Amazon was one of three on-line marketplaces that offered pressure cookers that the Program found to have high levels of lead.
[4] The letter does not define cookware, but it appears to be any foodware or other food contact material used to cook food or food ingredients.
It’s been a few years since Are Your Dog’s Food Bowls Safe? A Pet Bowl Materials Guide was published. Since then, stainless steel products have surged in popularity and can be found in a number of products for both humans and pets. As such, there has been a significant increase in manufacturers of stainless steel items that range from low to high quality. With the EPA awareness now prevalent and a abundance of stainless steel bowls vendors now available, there is a new controversial debate and hot topic going on right now: Can stainless steel bowls contain lead?
The answer, at least from a technical standpoint, is: No, there is no lead used to make stainless steel.
However, there are some considerations on how lead can potentially be in some stainless steel product and how it could affect you and your pets. If you’re not interested in the science, you can skip to the end: lead in stainless steel conclusion. Otherwise, let’s take a look at what exactly stainless steel is and how it differs from ‘regular’ steel.
Steel, by definition, is primarily composed of iron. Iron is a naturally-occurring metal on earth. It is rarely found on the surface because it oxidizes readily in the presence of oxygen and moisture—becoming iron oxide (also known as rust). Because pure iron is relatively soft, other metals are often added to strengthening it into an ‘alloy’. Steel—which can be 1,000 times harder than pure iron—is made by alloying iron with small amounts of other metals and carbon.
There are two basic types of steel: carbon steel and stainless steel.
Carbon steel is most commonly used to make auto bodies, appliances, and sheet metal (fabrication/panelling). It’s easy to distinguish carbon steel because it turns black over time and easily rust when exposed to air and moisture. Carbon steel is made of iron with 0.1 to 1.2 percent carbon and even less manganese.
The majority of consumer products made from steel, such as cookware, bakeware, and cooking utensils are made from stainless steel. Stainless steel is defined as a steel alloy with a minimum of 11% chromium content by mass. Unlike carbon steel that is susceptible to rusting and turning black, stainless steel has the unique advantage of being able to resist stains and corrosion due to its chromium content.
The chromium provides a layer of chromium oxide over the steel when exposed to oxygen. This layer is impervious to water and air, protecting the metal beneath. When the surface is scratched, the layer quickly reforms itself in a process known as passivation that is often seen in other metals, such as aluminum and titanium. Therefore, when food or water or your body comes in contact with stainless steel, it is actually contacting chromium.
Over 70% of stainless steel manufactured is of the 300 series meaning that it has been heated to a temperature high enough to change its crystal structure to a form known as austenite. 300 series stainless must contain a maximum of 0.15% carbon, a minimum of 16% chromium, and sufficient nickel and/or manganese to retain their crystalline structure. These stainless steels are named by their chromium and nickel content. The most common is 18/8 stainless which is defined as a composition of 18% chromium and 8% nickel. 18/0 and 18/10 are also available.
The most common grade is Type 304, which is referred to as A2 or 18/8 stainless steel.
The second most common austenite steel is Type 316 grade, also called marine grade or surgical stainless. In addition to chromium and nickel, Type 316 also contains molybdenum to help maintain a cutting edge and prevent specific forms of corrosion. It is typically used in the manufacturing and handling of pharmaceutical and food products where the minimization of metallic contamination is required.
Type 440 grade is commonly used for make knives due to its increased ability to maintain a sharp edge.
As you can see, there is no lead used in the production of stainless steel. Even if the product is made in China, there would be no reason why a manufacturer would randomly add lead to the stainless steel formula. Doing so would likely disrupt the stainless steel formulas and it may not set or perform properly. So then…
Based on what I could discover from a few sources including my wife (a chemist), the potential of lead contamination in stainless steel can be due to a few factors:
1. Lead residue. Similar to how some food products has warning labels such as “may contain nuts” or “manufactured in a facility that processes tree nuts” despite not being a nut-based product at all, the stainless steel could have been made in a facility that also make products containing lead. Think of it as lead ‘dust’. The good news is this is a simple fix. Simply thoroughly clean your stainless steel products before use. The lead dust will wash off and your stainless steel products should be fine for use.
2. Not stainless steel. The product in question may not actually be stainless steel but some other type of metal or alloy. The magnet test is not a proper test because the differing amounts of metals in stainless steel can differ and affect its magnetic properties. The best way to test stainless steel requires potentially damaging it: select a spot or item you don’t mind testing and use an eye dropper with muriatic (hydrochloric) acid on it, wait an hour; discoloration and corrosion will occur on stainless steel. As such, the effective solution to this concern may be to focus on obtaining your stainless steel from reputable and proven stainless steel brands and manufacturers.
Lead-based coating. If your stainless steel item is painted or lined, this can be a huge concern. While it is stainless steel, the paint or coating applied could contain lead. The best solution is to avoid stainless steel products that is painted or advertised with an internal coating unless it came from a reputable company. Lead-based paint tend to occur most frequently for products made in China. If you have any, I would highly recommend you replace the product or—at the very least—test it for lead using an instant lead kit such as3.. If your stainless steel item is painted or lined, this can be a huge concern. While it is stainless steel, the paint or coating applied could contain lead. The best solution is to avoid stainless steel products that is painted or advertised with an internal coating unless it came from a reputable company. Lead-based paint tend to occur most frequently for products made in China. If you have any, I would highly recommend you replace the product or—at the very least—test it for lead using an instant lead kit such as 3M LeadCheck swabs
4. Solder containing lead This typically does not occur in bowls, but many insulated stainless steel bottles use a solder that may contain (but not always) lead to vacuum seal the stainless steel bottle. Most of the time, these spots have a protective cover and is only located on the exterior so it should not affect the interior contents in any way.