Hi Jewels,
The latex that is used in the OMI mattresses is a high quality material and latex in general is the most durable of all the foam materials.
In addition to the durability of latex … all the latex you are likely to encounter (either Dunlop or Talalay that is made with either natural or synthetic rubber or a blend of both) will have a reliable certification such as Oeko-Tex, Eco-Institut, or Greenguard Gold (see post #2 here) and based on actual testing I would consider any type or blend of latex to be a very “safe” material in terms of harmful substances and VOC’s.
There is also more about the 3 most important parts of the “value” of a mattress purchase in post #13 here which can help you make more meaningful quality/value comparisons between mattresses in terms of suitability (how well you will sleep), durability (how long you will sleep well), and the overall value of a mattress compared to your other finalists based on suitability, durability, and all the other parts of your personal value equation that are most important to you (including the price of course and the options you have available after a purchase to fine tune the mattress or the exchange/return options that are available to you).
While the price of a mattress is just one part of the “value” of a mattress purchase … OMI in general is certainly in a higher or often a significantly higher budget range than many other mattresses that use very similar materials (including 100% natural latex or organic latex) so I would make sure you make some very careful “value” comparisons with other latex mattresses that are available to you either online or locally based on all the parts of your personal value equation that are most important to you.
Phoenix