Complex sentence: Its use is discouraged because coupling using BOP liberates HMPA which is carcinogenic, although for small scale use in an organic laboratory this is not a great disadvantage as it is in large scale industrial usage.
Split into simpler sentences: Its use is discouraged because coupling using BOP liberates HMPA, which is carcinogenic. Although for small scale use in an organic laboratory this is not a great disadvantage as it is in large scale industrial usage.