Although C-DBPs were present in relatively high concentrations, N-DBPs should not be ignored because they Cy5 hydrazide are more toxic than C-DBPs . Three N-DBPs (DCAN, TCAN and TCNM) were formed in SMPs treated with chlorination under different conditions (Fig. 3). While the amount of TCAN was almost constant (1.6–1.9 μg/L), the amount of DCAN and TCNM varied greatly under different conditions (DCAN: 1.3–8.2 μg/L; TCNM: 0.2–3.1 μg/L). Compared with NS condition, the formation of N-DBPs was higher under HA, HS and HT conditions, but was lower under HM condition. For example, the amount of TCNM was 10 times higher under the HA condition than community succession under NS condition, owing to the high ammonia content under HA condition. Hypochlorite can react with ammonia first and convert to chloramine disinfection, thus significantly increasing the amount of N-DBPs . HT and HS condition also promoted the formation of N-DBPs, probably due to the large proportion of SMPs with low MW, which could produce higher amount of N-DBPs .