Industrial farms feed their animals soy and corn, which is stored and therefore contains molds, including Ochratoxin A.

'Uncured' bacon is usually treated with celery salt and a bacteria culture. The bacteria transform the nitrates from celery salt into nitrites, and end up containing up to twice the amount of nitrites than their cured counterpart.

Obligatory links:

http://www.foodsafetywatch.org/factsheets/ochratoxins/

http://www.westonaprice.org/health-topics/soy-alert/save-you...