Hi SD_Deb,
Just like the first step in buying a “green” mattress is to decide on which types of materials or mattresses are “green enough for you” … the first step in buying a mattress that you consider to be “safe enough for you” or “natural enough for you” would be deciding on which materials meet your criteria for either one. Each person’s answer to these and the materials that they are most comfortable having in their mattress can vary widely.
There is more about natural and synthetic materials in mattresses and some comments about their relative safety in post #2 here and post #6 here.
There is also more information in post #2 here and the other posts and sources of information it links to that would be a good starting point for those who are interested in doing even more detailed research yet into the very complex, controversial, and often frustrating and confusing issues connected to mattress safety that can help them sort through the conflicting information on both sides of the discussion.
Once you have decided on the materials you are comfortable with having inside your mattress … then you will be in a much better position to start looking for and testing mattresses that meet your criteria.
The better options and possibilities I’m aware of in and around the San Diego area are included in post #2 here and for the Los Angeles region are in post #2 here.
Phoenix