Yes, it is included in the mix.
Residual nitrite concentration is a well-known risk factor in the potential formation of carcinogenic nitrosamines. Several factions of the 'food police' aver that no cured meats should be eaten ever. Among cooler heads, many feel that eating these products seldomly is fine, others that consumption in moderation is okay.
Proprietary curing mixes (like Hi Mountain's cures, including their Buckboard cure, Morton's TenderQuick, et al.), as well as homemade curing mixes made from reputable recipes contain only tiny quantities of sodium nitrite (sometimes with sodium nitrate as well) as only very small amounts are needed to act as anti-microbials, set color and extend shelf life. The primary curing agent is table salt.
That said, the mixtures noted above and/or their nitrite or nitrate components should only be used as specified in recipes. They should be stored out of the reach of children and labeled in such as way as to strongly discourage their use by the unsuspecting. Mistakenly used to sprinkle on food as one would table salt might expose that individual to toxic amounts of nitrite/nitrate. It is for this reason that 'pink salt' (sodium nitrite; aka Prague powder #1, Inst-cure #1, DC Cure #1) is dyed pink--to distinguish it from ordinary salt. Most #2 powders (sodium nitrate, same names as above), TenderQuick, Hi Mountain blends, and many others, are not dyed-but would still be potentially dangerous if consumed directly.
