For starters, please consider reading this linked study (click the image below)
which discusses this concern in detail:
There are two reasons vintage plastics often have lead:
- In brightly-colored vintage plastics, the toxicants (Lead, Mercury, Arsenic and Cadmium) are often used as components of colorants in the plastics.
- I have also found that vintage flexible/pliable plastic and rubber items (like electric cords, Christmas lights, extension cords and similar) often have high levels of Lead — regardless of the color. Years ago it was explained to me (by a research-scientist friend of mine who had direct knowledge of the subject) that this was because these plastics were likely treated with Lead in the forming process for two reasons: either to make them/keep them flexible and supple (less prone to brittleness & cracking), and/or to imbue some degree of fire-retardancy to the ones that are specifically electrical in nature. In newly-manufactured electrical cords, one can still sometimes find Lead, but now Antimony has become more prevalent – likely due to it’s touted fire retardant properties.
For the recent vintage Tupperware testing I have done, I found the following examples (I will update this as I post more examples of different colors):
- Brown plastic: No Lead, Mercury, Arsenic or Cadmium [Link]
- Light yellow plastic: Positive for Lead and Arsenic [Link]
- Olive green plastic: Positive for Lead and Arsenic [Link]
- Bright yellow plastic: Positive for Cadmium and Mercury [Link]
- Orange plastic (two examples, similar results): Positive for Cadmium and Mercury [Link]
From the linked study:
“Why are hazardous metals present in so many old nonvinyl toys? The metals are almost certainly colorants or pigments. Lead chromate, PbCrO4, also known as chrome yellow, was a standard plastic colorant in the era in which these toys were made. Lead sulfate (PbSO4) and lead oxide (PbO) were mixed with the chro- mate in varying amounts to produce a color palette from light yellow to red (Rangos, 2003).
Similarly, cadmium compounds such as cadmium sulfide and cadmium selenide were — and still are —used to produce yellow and orange hues in plastics (Rangos, 2003; Vonke- man, Thornton, & Makuch, 2001). Mercury- cadmium sulfides were also used to produce colors from orange to maroon (Rangos, 2003).”
Of course Tupperware fans have been very upset about the test results that I have shared recently (of my findings of toxicants in vintage Tupperware products), but the important thing to emphasize is that this is VINTAGE product — things made 40 to 50 years ago. This is not likely a concern for any of the new product (as, for a newly-manufactured plastic product to test positive for these toxicants at these levels, would be a violation of the subsequently-enacted contemporary regulatory standards.)
When these vintage products were produced regulatory standards for consumer goods ranged from being non-existent to ineffective (not protective of human health.) Additionally, when these products were made, the compact, portable scientific instruments and software (like the XRF instrument I use in my work) enabling spot-testing/field-analysis of consumer goods did not yet exist — and the instrumentation that did exist was not able to detect toxicants at the levels (and with the degree of precision, accuracy and specificity) of modern instrumentation.
As always, thank you for reading and for sharing my posts.
Please let me know if you have any questions.