Hi mike7,
Post #1 here links to all the basic information, steps, and guidelines you will need to make the best possible choices.
You can read more about the different types of latex in post #6 here. All of them are Oeko-Tex certified for any offgassing and harmful substances but there will still be some smell in the short term. Dunlop tends to smell more like rubber and Talalay has more of a sweeter smell. Neither smell is harmful and both dissipate (although the Dunlop can take a little longer to dissipate below what you are able to smell.
Some of the better options and possibilities in the Los Angeles area where you can test many different types or layerings of latex mattresses and become more familiar with them are listed in post #2 here.
Phoenix