What is the “greeting” that equiano receives when he first steps below the decks of the ship?

The greeting was stench

This stench came from various sources including but not limited to sweat, blood, dead bodies, fecal matter, urine, and other various sources, and they mixed together to be a "greeting" for Equiano who had never experienced anything like that before he was taken into slavery and put into the ship. He explains how he only wanted to die because of that.