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Abstract: Spatial distribution of nonylphenol polyethoxylates (NPEOs) and nonylphenol (NP) was investigated in a field study in Lanzhou Reach of the Yellow River. NPEOs and their metabolites were found in the river, with the maximum dissolved concentrations of 6.38 nmol/L for NPEOs, 0.19 nmol/L for nonylphenol ethoxy acetic acids (NPECs) and 0.79 nmol/L for NP, respectively. The maximum concentrations in the sediment and suspended particle samples were 1.50 and 5.09 nmol/g for NPEOs and NP, respectively. The effects of particles, light and microorganism on the dissipation of NPEOs in the river water were investigated based on lab-scale experiments. When natural particles were removed, 72% and 22% degradation of NPEOs were achieved at 120 h in non-sterile and sterile conditions with light, respectively. Different concentrations of NPECs were also observed in these experiments. When suspended particle matters (SPMs) were present, about 38–50% of NPEOs were sorbed to the particulate phase in only 1 h. As a result, the degradation of NPEOs and production of NPECs were inhibited. However, the combined sorption and degradation in the presence of SPMs resulted in lower dissolved NPEO concentrations than those in the absence of SPMs. Biodegradation was the most important pathway for NPEOs degradation in the river water, while NPECs seemed to be produced through both biological and abiological pathways. [Copyright &y& Elsevier]

Iron and steel production is one of the most significant anthropogenic sources of atmospheric mercury emission. However, there is little information about this source in China. In this study, we focused on three typical Chinese sintering furnace processes. Mercury in flue gas was sampled using the EPA Method 30B and Ontario Hydro Method, and solid samples were also analyzed. We found that 1.12–4.66% of mercury input in sintering furnace processes was emitted into the atmosphere. The total mercury concentrations in the sintering furnace flue gas were 17.773, 31.765 and 18.275 μg/m 3 ; the major mercury species was oxidized form, which accounted for 73.4– 94.7% of the total mercury. The mercury concentrations in the stack flue gas were 0.373, 0.533 and 0.465 μg/m 3 , while its removal efficiencies by air pollution control devices (APCDs) were 97.5%, 81.1% and 96.8%, and its emission factors were 2.49, 2.71 and 1.28 mg/t sinter. The main mercury inputs were iron ore, coal, coke and lime, where the iron ore input was 74.84– 92.22% of the total mercury quantity. Moreover, mercury was distributed in fly ash (19.22– 81.54%), gypsum (13.29– 46.00%), iron ore sinter (0– 11.45%), and flue gas (1.12– 4.66%). An approximate mercury mass balance could be obtained from various samples in this study. [ABSTRACT FROM AUTHOR]