Products treated with EcoPure® biodegrade as a result of microbial digestion. The process of microbial digestion can take place in either aerobic (with oxygen) or anaerobic (without oxygen) conditions. These conditions determine what by-products are produced. In aerobic microbial environments, the by-products will be carbon dioxide, water, and humus. Humus is the degraded organic material in soil, which causes some soil layers to be dark brown or black. In soil science, humus refers to any organic matter that has reached a point of stability, where it will break down no further. For anaerobic microbial environments, the by-products will be carbon dioxide, methane, and humus.