For follow-up discussion and general commentary on the topic. Comments are sorted chronologically.
The bible speaks of "slaves" but not that much of "slavery." The practice isn't addressed in a way that would satisfy an answer to this question. We see admonitions about how to treat "slaves," but not much at all about the practice of owning people. The "slavery" we read about in the bible was more of servant hood than anything we think of when we see the word "slavery."
Some people were responsible for other people because of a variety of reasons. War led to people "owning" other people. This "owning" was more about being served by people than it was about "building a national economy from the exploitation of another nation of people." That's what the slavery being asked about here is about. It's about using people to further a business venture and discarding them when they're no longer needed.
"Slave labor" was what Israel was used for during their enslavement in Egypt. That was talked about in a way to reveal it as being a horrible practice. The practice of slavery perpetrated by western nations somewhat mirrored that institution.
"Human trafficking" speaks for itself. That doesn't describe what was happening with Jacob and his servants, or Abraham and Hagar. The people who "owned slaves" ("possessed" servants) wasn't practicing "human trafficking."
The bible doesn't have to tell us how despicable it is for a people to sail thousands of miles to another continent, BUY PEOPLE, (the sellers are just as despicable) and use them the way it happened here... we know...