The entire
Dalbergia genus - cocobolo and true rosewood included - is loaded with poisons designed to protect the tree from year-round insect assault. Bubinga darkens in the light, and is an African "rosewood" in the trade. Apparently not as horrible as the others.
http://www.wood-database.com/wood-artic ... -toxicity/
First, have some elixir Benadryl within arm's reach of the lathe, right next to the CA debonder bottle you should replace every three to four years. First wheeze or feeling of tightness in your throat turns off the lathe, takes off clothing with shavings adhering, and takes a dose of the stuff. Exit the room after cleaning off the bare skin. From then until forever, use a charcoal filter respirator when using the wood.
More common problem is dermatitis, which generally responds to a bit of topical cortisone and some of the antihistamine. Here's a good article on what to do.
http://www.woodworkerssource.com/wood_toxicity.php#
Tropical woods tend to grow at nearly the same rate year round, so there isn't usually the great difference we see between spring (rainy season) and fall (dry season) wood from temperate regions. The woods you mention are dense and hard, but not nearly as dense or hard as steel, so present your tools properly for cutting short-grained woods and you should have no real problem.