1. Treated lumber- the chemicals used to prevent rot and insects make for dangerous smoke.
2. Redwood- wood contains natually occurring toxic chemicals
3. Pine and fir- generate high amounts of creosote, hazard of chimney fires (can be used, but with care and cleaning the flue) Low heat values.
Firewood log racks are the best way to store firewood. There are multiple sizes and shapes that can be used to store large quantities of wood outdoors as well as small amounts of firewood next to your fireplace. It's also very helpful to have a log cart or carrier of some kind to transport wood from the outdoor log rack to the indoor firewood storage.
Fir and pine trees make good kindling for starting a fire but the pitch of this kind of wood creates more creosolt buildup which can cause your chimney or stove pipe to catch on fire. An occasional fire of pine wood is beautiful and aromatic, but short lived. Hardwoods such as maple or oak burn slower and heat better. Personally, I would never burn spruce in a home fireplace or stove. You do not want any creosote buildup.
chemical
Depends on what kind of fireplace! Need more info
Any kind of hardwood that is seasoned. i.e. oak or walnut that has been seasoned for at least a year.
radiation
Basically any sort of wood can make a good material for firewood, be it logs or branches. However, some species of wood are better than other, such as tamarack or birch, which produce more heat when burned.
Cedar is a great wood to burn if you want to repel bugs. I wouldn't stop with wood though, there are a number of plants you can burn as well. Some plants to try are citronella, lemongrass, rosemary, and thyme.
A safe fireplace screen is made of metal but won't overheat when touched.
fireplace
Hard wood the tighter the grain the better.
The wood fireplace goes back thousands of years and no one knows who invented it. Benjamin Franklin invented a particular kind of stove (not a fireplace) that was more effective and efficient than a fireplace in warming a room and in fuel consumption. The Franklin Stove was also easier and safer to use for cooking than a fireplace was.