What is Depression Era Glass?
According to the National Depression Glass Association (NDGA), Depression glass is glassware manufactured in America from the early 1920s through the end of World War II in 1945.
This period of manufacturing is what defines a piece of glassware as Depression glass.
It often came in colors like green, pink, blue, and amber.
Is Depression Glass Toxic?
Depression glass can be leaded or unleaded glass, it often had arsenic added as a bubble-reducing agent, and further additives like Uranium (a radioactive element) were added, dependent on the color.
- Green Depression Glass: Chromium and/or Uranium
- Yellow Depression Glass: Uranium
- Blue Depression Glass: Cobalt
- Brown Depression Glass: Nickel
- Amber Depression Glass: Carbon, Sulfur, Iron
- Purple Depression Glass: Manganese
- Red Depression Glass: Gold, Selenium
- Alexandrite Depression Glass: Neodymium
- (Source)
Lead, Arsenic, and Uranium can all find their way into the food or drink and become a risk to the user.
Dr. Lyle Burgoon, a Toxicologist, contributed to this article by providing the risk assessment for each type of Depression glass.
Does Depression Glass Contain Radioactive Elements like Uranium?
Only some colors of Depression glass contain Uranium; Uranium gives glass a yellow or green color and is referred to as Uranium Glass.
You can test your glassware for Uranium by exposing it to UV light (i.e. a black light). If it is positive for Uranium it will fluoresce (glow) from the UV exposure.
The U.S. Environmental Protection Agency (EPA) recommends against eating or drinking from Uranium glassware.
But because the glass only contains a small amount of Uranium, many websites argue that this glass is safe to eat off of.
I asked toxicologist Dr. Lyle Burgoon about this and he explained that based on the Nuclear Regulatory Commission‘s data, “drinking from Uranium glassware would result in fairly negligible exposures to uranium – 0.002 mrem/year.
That’s about 100x less than the radiation dose per hour flying in an airplane. That’s also 5,000x less than the radiation from a single chest X-ray (EPA)”.
In the case where someone is handling collectible glass (not eating or drinking from it), Dr. Burgoon explains that “they will still only see at most an exposure of 0.2 mrem/year. That’s equivalent to the radiation from a 1-hour plane flight in one year”.
Does Depression Glass Contain Arsenic?
Regardless of whether the glass was leaded or unleaded, Arsenic was added to most glass formulas at this time.
It was used to reduce the bubbles that formed as the ingredients were being melted, says the National Depression Glass Association.
Although some of it volatilizes out in production, about 50% does remain (source).
Only one study looks at Arsenic released by the glass, but this is only showing us the leaching at 121 degrees C, which is hotter than the temperature water boils at.
There isn’t much more data to go by. Dr. Burgoon, a Toxicologist, explains that without knowing how much arsenic there is in the glass, and studies or testing to show how much leaches out with normal use, it’s not possible to assess the risk.
Not all Depression glass should be presumed positive for Arsenic, as Tamara’s testing (linked to below) shows a set of clear glassware that didn’t test positive for Arsenic.
You would need to test your glassware with XRF testing to know if it contains Arsenic.
Does Depression Glass Contain Lead?
Lime-soda glass (non-leaded) was used to make most of the dinnerware items in Depression glass.
The leaded glass was more often used to make blown items like stemware and vases, says the National Depression Glass Association.
Lead does leach out of glassware.
The quantity released depends on the amount of Lead in the glassware, the type of food or beverage used, and the length of time they are in contact with each other (source).
Unless you know all three variables for each piece of glassware, it’s not possible to accurately assess the risk, says Dr. Burgoon, Toxicologist.
Official recommendations by the Government of Canada and the FDA recommend that pregnant women and children should not use leaded glassware to eat or drink from.
You would need to test your specific glassware set to know if it’s positive for Lead.
Is Clear Depression Glass Safe to Use?
Tamara Rubin tested a set of clear Depression glasses, which only showed trace Antimony and Cadmium which would be considered safe by all standards to eat off of.
Is Pink Depression Glass Safe to Use?
Pink Depression glass is not one that should be singled out as particularly toxic based on the pink colorant.
Like all Depression glass, it could contain Arsenic, Lead, or other metals. You would need to test it to be sure.
How do You Know if Your Depression Glass Contains Toxic Metals?
To detect Uranium you could put the yellow or green glassware under a UV black light to see if that causes it to glow.
To detect Lead, Arsenic, and other metals you would need to complete XRF testing of the items. Please see this post for more details on how to test items with an XRF analyzer.
Toxicologist Dr. Burgoon concludes that he is “less worried about the Uranium, and more concerned about the unknowns with respect to Arsenic and Lead.
Unless someone is willing to do the testing to assess how much Arsenic or Lead is in their glassware, how their intended use will leach out the metals, and at what rate, there would simply be too much uncertainty for me to be comfortable using it for food use”, he says.
Dr. Burgoon is a trained regulatory toxicologist, risk assessor, and biostatistician. Dr. Burgoon earned his dual Ph.D. in Pharmacology and Toxicology with Environmental Toxicology from Michigan State University.
Corinne Segura is an InterNACHI-certified Healthy Homes Inspector with certifications in Building Biology, Healthier Materials and Sustainable Buildings, and more. She has 10 years of experience helping others create healthy homes. You can book a consult here.
Lisa M. Asafi
Just came upon your site. THANK YOU for caring, for doing the research and sharing. xo
Corinne Segura, Building Biologist
You’re very welcome
Cathy Dostal
Hello. I have some cobalt blue glasses & plates and some ruby red glasses that I use once or twice a year at holidays. (They are beautiful and set a gorgeous table) We drink water or ice tea from them. I can’t believe that is enough to cause a problem, is it?
Corinne Segura, Building Biologist
I can’t really do a toxicological assessment of that here. But you may also need to know the lead and arsenic content, if any. Or you could look at leaded glass and see if using it twice a year with an acidic beverage like tea is significant. It may not be.
Jill
Look, I’m so tired of seeing all these articles against drinking and eating off uranium glasses and dishes. You are exposed to way more radiation on an airplane for an hour than you’ll ever be eating a lifetime from these dishes. Make sure your science is actual science. I often see that whoever is paying the most money to keep truth from getting out about the actual benefits of these dishes is the one making up the “science”.
Jill Reynolds
Look, I’m so tired of seeing all these articles against drinking and eating off uranium glasses and dishes. You are exposed to way more radiation on an airplane for an hour than you’ll ever be eating a lifetime from these dishes. Make sure your science is actual science. I often see that whoever is paying the most money to keep truth from getting out about the actual benefits of these dishes is the one making up the “science”.
Sarah
Any suggestions for new lead-free drinking glasses?
Corinne Segura, Building Biologist
On tamara rubin’s site there are some
Sarah
Thank you. I forgot about her site. I’m lazy and come here all the time. I need to check her out for things related to the kind of work she does. Slim pickings in terms of options for lead free glasses, but no big deal. The priority is health and something to pour water into! Bought some. Thanks for directing me there!
Lynda Paleshnuik
Thanks for this article, very interesting. I’m actually interested in cobalt leaching from heated old cobalt blue glass… as I reheat my tea in the microwave in an old measuring cup. I’m guessing it isn’t much of a danger, as humans are normally low on cobalt, and I don’t heat for long or very hot. But of course too much is an issue, so I do wish leaching of cobalt had been included or there were some references for more information for the metals/elements not covered.
Todd
We’ve found it safe, unless ground up – and the dust licked and snorted. Otherwise . . . we are pretty fortunate that glass is as stable as it is eh?
Corinne
lead and other toxic metals do leach quite easily into liquids, especially acidic ones, depending on the contact time.