Tissue phantoms are materials designed to mimic the dielectric properties of biological tissues. This work proposes eco-friendly tissue phantoms of cartilage, cerebrospinal fluid and stomach in the frequency range between 0.4 and 6 GHz. For reaching this purpose, Triton X-100, a non-ionic surfactant is replaced by ECOSURF SA-9 seed oil-based non-ionic surfactant. Whereas Triton X-100 is very toxic to aquatic life, causes eye damage and sky irritation and is not biodegradable, ECOSURF SA-9 is a biodegradable and low risk non-ionic surfactant with similar dielectric properties to Triton X-100. The proposed phantoms are prepared and measured using both non-ionic surfactants, obtaining a good agreement between them. Therefore, it is shown that ECOSURF SA-9 is a safer and eco-friendlier alternative to Triton X-100 that permits to obtain biodegradable, safe, low cost, ease-to-prepare and time-stable phantoms.