Bikinis are typically made from nylon and lycra, fabrics that are not biodegradable. Green bikinis are made from organic, sustainably-grown, cotton, soy, and bamboo-based fabrics.
Eco friendly bikinis are becoming easier to find today but the place that seems to be ahead of the others in the movement of making bikini fashion eco friendly is Niksters.com. The bikini pictured above is from Niksters and is made of soy and organic cotton.
There are other places to look too, but you will run into problems if youdo a search for "green bikinis". It will likely bring up green colored bikinis. The best search term will be "eco friendly bikinis".