Hi. We have switched away from solvent adhesives which typically involve neoprene dissolved into toluene, which if not proven to be carcinogenic, is certainly not healthy to breathe. We have gone over to dispersion adhesives which typically involve neoprenes dispersed into less toxic mediums. This negates the need for thorough extraction, but rather just good ventilation just because fresh air is good for you.
The dispersions generally can't be used as cold contact adhesives and have longer opening times, that is you have to wait longer for them to 'dry' before heat activating them. Also they have to be more thoroughly and accurately heated to achieve a good bond. The safest dispersion adhesives use water as a medium. These water based products take about 10 minutes to dry and require uniform heating to about 120 c to activate.
Solvent adhesives are so easy and effective to use it is no wonder that their use caught on and they continue to be used, but they do need thorough extraction and removal of the solvents from the air before it is re-circulated.
We still extract but just into the outside air as the fumes are not pollutant. We tried water based but have gone for a toluene free German product, Renia Top fit. In the UK a number of firms market this under their own label. http://www.algeos.com/html/products/...ves/renia.html