Walk into any adult toy store—or browse any online shop—and you’ll see toys made from a confusing range of materials: silicone, TPE, TPR, jelly, rubber, ABS plastic, glass, stainless steel. Not all of these are safe for internal use, and the differences matter for your health.
In this guide, we’re focusing on the two most common body-safe alternatives: liquid silicone and TPE (Thermoplastic Elastomer). Both are marketed as “body-safe” and “phthalate-free,” but they’re fundamentally different in ways that affect safety, longevity, and value.
What Is Liquid Silicone?
Liquid Silicone (often labeled as LSR or “liquid silicone rubber”) is a premium material made from—surprise—silicone. During manufacturing, liquid silicone is injection-molded at high temperature, creating a fully cured, non-porous finished product.
Key properties:
- Non-porous: No microscopic holes means bacteria, mold, and fungi cannot penetrate or harbor in the material
- Hypoallergenic: Rarely causes allergic reactions, even in sensitive individuals
- Heat-resistant: Can be boiled for sterilization (non-electronic toys)
- odor-resistant: Doesn’t absorb or hold odors from use
- Long-lasting: With proper care, silicone toys can last years without degrading
What Is TPE?
TPE (Thermoplastic Elastomer) is a blend of plastic polymers and rubber. It feels similar to silicone—soft, flexible, skin-like—but is manufactured differently. The problem: TPE is porous.
Key properties:
- Porous: Microscopic pores in the material can trap bacteria, fluids, and contaminants that can’t be fully removed by washing
- Shorter lifespan: Oils from the material can leach out over time, causing the toy to become sticky or misshapen
- Cannot be fully sterilized: Boiling or heat will damage TPE; you can only clean the surface
- Often cheaper: Lower manufacturing cost means lower retail price—but you get what you pay for
The Critical Difference: Porosity
Here’s the key distinction that most articles gloss over:
Both silicone and TPE can be described as “body-safe” when new. But only silicone remains body-safe over time because it’s non-porous. TPE’s porous nature means:
- Bacteria from previous uses can remain embedded even after cleaning
- Mold can develop if the toy is stored damp
- The material breaks down faster with oil-based lubricants
The FDA considers silicone a Class VI medical-grade material. TPE doesn’t meet that standard for internal use.
Visual Comparison
A simple home test: if you stretch a small piece of silicone, it returns to its original shape without any visible changes. TPE tends to stretch and leave marks or whitening. Silicone also has a noticeably denser, higher-quality feel.
How to Tell If Your Toy Is Silicone or TPE
- The flame test: A small silicone scrap will turn to white ash when burned; TPE melts and forms a black, oily residue. (Do this only on a toy you don’t care about.)
- The oil test: Put a small drop of oil on an inconspicuous area. Silicone absorbs nothing; TPE may darken or swell.
- The price clue: If a toy claims to be “silicone” but is very cheap (under $15 for a dildo), it’s likely TPE or a silicone-TPE blend.
- The stretch test: Silicone stretches and rebounds cleanly. TPE often leaves visible stress marks.
What About “Silicone Blend” Toys?
Some manufacturers mix silicone with TPE to reduce cost. These are NOT the same as pure liquid silicone—the porosity issue still applies, just to a lesser degree. Always check the material label or contact the manufacturer if unsure.
The Bottom Line
If you want the safest, longest-lasting sex toys, choose liquid silicone. Yes, it costs more—but a quality silicone toy from a reputable brand like Mutanttoys will outlast and outperform TPE alternatives many times over.
TPE isn’t dangerous when new and used carefully, but it requires more diligent cleaning, can’t be sterilized, and degrades faster. For anything you’ll use frequently or internally, silicone is worth the investment.
Explore Mutanttoys’ collection of 100% liquid silicone dildos—body-safe, hypoallergenic, and built to last.