A Collector’s Guide to Radioactive Antiques: Safety and Awareness

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Antiques carry a rich history, but sometimes these historical relics contain radioactive materials—the type that gets people to wear hazmat suits. Understanding the risks associated with radioactivity can help collectors make informed decisions about handling and displaying their treasures.

This article explores various types of radioactive antiques, discusses their risks, and offers tips on handling them safely. Besides radioactivity, collectors should also be aware of other potential health hazards posed by antiques, including the presence of lead.

Radioactive Materials in Antiques

According to the US Environmental Protection Agency (EPA), certain antique items might contain radioactive materials. Some of these antiques include:¹

Clocks and Watches with Radium Dials

• Manufactured from the early 1900s to the 1960s
• Radium was used to make the clock and watch dials glow in the dark
• Radium can be hazardous if ingested or inhaled

Vaseline or Canary Glass

• Produced in the late 1800s to the mid-1900s
• Yellow-green color is due to the presence of uranium
• Generally considered safe to handle but should not be used for food or drink

Thorium-containing Gas Lamp Mantles

• Manufactured before the 1990s
• Thorium was used to improve the brightness of the gas lamp mantles
• Can emit small amounts of radiation when handled

Fiestaware

• Produced from the 1930s to 1970s
• Known for their bright orange-red color, which is due to the use of uranium oxide glazes*
• Modern Fiestaware no longer contains radioactive materials

Other Radioactive Ceramic Glazes

• Used in various ceramic and pottery items from the early 1900s to the 1950s
• May contain uranium, thorium, or potassium*
• Could pose a risk if ingested or inhaled

*Radioactive ceramic glazes can come in various colors, depending on the specific radioactive material used and other ingredients in the glaze. For example, uranium oxide, which was commonly used in ceramic glazes, can produce colors ranging from yellow to orange-red, depending on the concentration and firing conditions.²

Risks Associated with Radioactive Antiques

Radioactive materials emit ionizing radiation, which can potentially harm human health. However, the risk associated with radioactive antiques depends on several factors:

• The specific radioactive material present in the antique
• The amount of radioactive material in the item (and how it compares to background levels)
• The distance between the person and the radioactive source
• The duration of exposure to the radioactive material

In general, the risks associated with handling radioactive antiques are relatively low, but they should be treated with caution, especially if the antique is damaged, radium paint was used, or if the radioactive material can become airborne or ingested.¹

Detection and Measurement

Detecting and measuring radioactivity in antiques can help enthusiasts better assess the risks associated with their collections. This section will cover basic tools and techniques for measuring radioactivity and interpreting the measurements.

Tools and Techniques for Measuring Radioactivity

There are several instruments available to measure radioactivity in antiques, including:

1. Geiger-Muller (GM) counters. These devices detect ionizing radiation and provide a count rate, typically measured in counts per minute (CPM) or microsieverts per hour (μSv/h). They are widely available and easy to use but may not be sensitive enough to detect low levels of radioactivity in some antiques.³
2. Scintillation detectors. These devices use scintillating materials to convert ionizing radiation into visible light, which is then detected and measured. Scintillation detectors can be more sensitive than GM counters, but they are also more expensive and may require more technical expertise to operate.

Interpreting Measurements

When measuring radioactivity in antiques, it’s essential to understand the context of the measurements and how they relate to potential risks. Factors to consider include:

1. Background radiation. It’s important to account for your environment’s natural background radiation levels, as they can influence the measurements taken from antiques. Background radiation levels can vary depending on factors such as altitude and local geology.
2. Radiation dose rates. Understanding the dose rates associated with specific radioactive materials can help determine whether an antique poses a significant risk. For example, uranium, thorium, and radium have different dose rates and potential health effects.⁴

Sources

1. Radioactivity in Antiques. US Environmental Protection Agency, 2022.
2. National Low-Level Waste Management Program Radionuclide Report Series. International Atomic Energy Agency, 1995.
3. What is a Geiger Counter? United States Nuclear Regulatory Commission, 2020.
4. Radiation and Health Effects. World Nuclear Association, 2022.