Fig. 2: Abundance of selected ARGs in livestock waste versus in other ARG reservoirs. This figure summarizes the data presented in Tables S2 and S5.

ARGs abundance in livestock waste from swine and chicken farms are higher (by three to five orders of magnitude) than in hospital and municipal waste, whereas the abundance of ARGs on cattle waste and fish ponds is similar to hospital and municipal waste. Some ARGs abundance data from solid waste (for livestock waste) or biosolids (for hospital and municipal wastewater) are still used in this figure because the density of solid wastes and wastewater are on the same magnitude (e.g., 1.02–1.06 g/cm³ for biosolids¹⁵⁵ and 0.9–1.1 g/cm³ for livestock waste¹⁵⁶), which can facilitate the comparison of ARG concentrations.