First, it's important to understand that many "copper" tongue scrapers aren't pure copper.
They're typically made of copper-plated metals or copper alloys like brass (copper and zinc) or bronze (copper and tin). Some may even be copper-colored but made primarily of other metals with just a thin copper coating.
The concerns about copper tongue scrapers relate to several issues:
- Oxidation: Copper naturally oxidizes when exposed to air and moisture, developing a greenish layer called patina (copper carbonate). This is the same reaction that turned the Statue of Liberty green. When this happens on a tongue scraper, you're potentially exposing your mouth to copper compounds that weren't intended for oral consumption.
- Corrosion and rust: While pure copper doesn't rust (rust specifically refers to iron oxide), copper alloys containing iron components can develop rust. Additionally, copper itself undergoes corrosion, producing compounds like copper oxide and copper carbonate. These corrosion products can potentially irritate oral tissues and may have an unpleasant metallic taste.
- Metal leaching: When copper oxidizes in a moist environment (like your bathroom or mouth), small amounts of copper compounds can dissolve or leach into your saliva. While copper is an essential mineral in small amounts, excessive copper exposure can lead to gastrointestinal issues and, in extreme cases, copper toxicity. Brass, a copper and zinc alloy, may cause allergic reactions, especially in people allergic to nickel.
- Bacterial concerns: The crevices created by corrosion and oxidation can harbor bacteria, potentially defeating the purpose of tongue cleaning, which is to reduce bacterial load.
For safer alternatives, consider tongue scrapers made of:
- Stainless steel (which resists corrosion)
- Medical-grade plastic
- Surgical-grade stainless steel
- Aluminum
- Silicone
These materials are less reactive, easier to clean thoroughly, and generally considered safer for oral use.