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Lead (Pb) exposure is a global environmental problem and its exposure can lead to serious renal damage by disturbing the pro-oxidant/antioxidant balance and facilitating inflammation. Chlorogenic acid (CGA) is one of the most abundant polyphenols in the diet and has been reported to have many biological properties such as antioxidant and anti-inflammatory. In this study, we aimed to investigate the protective efficacy and mechanism of CGA against Pb-induced nephrotoxicity in mice. The results showed that CGA inhibited Pb-induced bodyweight loss, reduced kidney coefficients, and alleviated renal function and structure. Exploration on the potential mechanism demonstrated that CGA suppressed Pb-induced inflammation in the kidney by regulating NF-κB pathway activation. Furthermore, CGA significantly increased Pb-induced reduction in the activity of SOD and GSH-Px, and reduced Pb-induced increase in the content of MDA. The expression of Bax and Bcl-2 associated with apoptosis was also significantly regulated by CGA. These data indicated that CGA may play a potential treatment strategy for Pb toxicity.

Small hydropower (SHP) in China has experienced soring development in the past two decades and has been assigned ambitious development goals recently, while its environmental performance remains unclear. This study is intended to provide a comprehensive assessment of the environmental impacts of SHP plants in China, to compare the results with its counterparts in other countries, and to identify the key factors in the mitigation of negative consequences. A life cycle assessment of a SHP plant in Guizhou Province of China was conducted in a cradle-to-grave manner following the ISO 14040 guidelines. The functional unit is defined as 1 MWh of net electricity produced by the plant. The CML 2001 method was applied to characterize the environmental impacts. The environmental impact categories considered in this study included global warming (GWP), abiotic depletion (ADP), acidification (AP), freshwater aquatic ecotoxicity (FAETP), human toxicity (HTP), and photochemical ozone creation (POCP). Further contribution analyses and sensitivity analysis was performed to identify the key contributors to each impact category during the life cycle of the plant. For the case plant, the considered impacts are caused primarily by the construction stage. As for the materials and energy inputs, cement, steel, and electricity are the three dominating ones for the overall environmental impacts. Compared with SHP plants in other countries, the plant performs similar to the MW scale plants in Thailand and Japan but worse than the plant in Switzerland. Further comparison of life cycle inventories (LCIs) revealed that the quality of hydro-energy resources and acquisition of indigenous equipment technology is essential to their environmental performance. The results of the sensitivity analysis suggested that the amount of construction materials and energy consumption as well as the plant output influences its environmental performance significantly. The construction stage of the SHP plant is the most important source of environmental impacts. To minimize the impacts of this stage, optimization of the structural design and application of new construction materials and good construction practices is recommended. In addition, determining suitable installed capacity and advancing equipment technologies to ensure the optimal output is also crucial to improve the environmental performance of SHP plants in China, regarding the current serious problem of unstable operation.

Assessing the extent to which all bio-fuels that are claimed to be renewable are in fact renewable is essential because producing such renewable fuels itself requires some amount of non-renewable energy (NE) and materials. Using hybrid life cycle analysis (LCA)—from raw material collection to delivery of pellets to end users—the energy cost of wood pellet production in China was estimated at 1.35 J/J, of which only 0.09 J was derived from NE, indicating that only 0.09 J of NE is required to deliver 1 J of renewable energy into society and showing that the process is truly renewable. Most of the NE was consumed during the conversion process (46.21%) and delivery of pellets to end users (40.69%), during which electricity and diesel are the two major forms of NE used, respectively. Sensitivity analysis showed that the distance over which the pellets are transported affects the cost of NE significantly. Therefore the location of the terminal market and the site where wood resources are available are crucial to saving diesel.