[Simultaneous determination of 7 benzodiazepines in human plasma by UHPLC-MS/MS].

The study was designed to develop the method for determination of 7 benzodiazepines concentration in human plasma. UHPLC-MS/MS was adopted to analyze plasma with protein precipitated by acetonitrile. Citalopram was used as an internal standard. Plasma samples were separated on CORTECS UHPLC C18 column with the mobile phase of aqueous solution (0.01% formic acid) - methanol (0.01% formic acid) at a flow rate of 0.3 m L·min(-1). Multiple reaction monitoring (MRM) mode was performed in combiation with electrospray ionization source operating in the positive ionization mode. The liner calibration curve of midazolam, nitrazepam, estazolam, clonazepam, lorazepam, triazolam and diazepam were obtained in the concentration range of 1.05-840 (r = 0.999 4), 2.06-824 (r = 0.998 1), 2.02-1 616 (r = 0.994 7), 6.18-2 472 (r = 0.997 9), 6.12-2 448 (r = 0.997 4), 3.02-2 416 (r = 0.990 2), 1.02-816 (r = 0.998 8) ng·m L(-1), respectively. The lowest detection limit were 0.02, 0.52, 0.51, 1.55, 0.77, 0.76, 0.02 ng·m L(-1), respectively. The RSD of inter-day and intra-day were less than 10.81%. The relative recovery was 81.46%-106.53%. The method was successfully applied to clinical analysis of blood samples from patients.

[Distribution Characteristics and Environmental Driving Factors of Cyanobacteria Community in Impounded Lakes and Reservoirs in Shandong on the East Route of South-to-North Water Diversion Project].

To investigate the distribution characteristics of the cyanobacteria community and the driving factors in impounded lakes and reservoirs in Shandong on the east route of the South-to-North Water Diversion Project, monthly samples of phytoplankton and the aquatic environment from Nansi Lake, Dongping Lake, Datun Reservoir, Donghu Reservoir, and Shuangwangcheng Reservoir were collected from May to November during 2010 to 2019. A total of 44 planktonic cyanobacteria taxa were identified with 23 filamentous cyanobacteria taxa. Pseudanabaena limnetica, Cylindrospermopsis raciborskii, Microcystis aeruginosa, and Microcystis wesenbergii were the dominant harmful cyanobacteria species, with a high detection frequency and abundance in all lakes and reservoirs. By analyzing the distribution characteristics of the cyanobacteria community in impounded lakes and reservoirs, we found that filamentous cyanobacteria had growth advantages in the water with large hydraulic disturbances, which should be the key points of cyanobacteria prevention and control in the future. Pearson correlation analysis and generalized linear fitting curve results showed that total nitrogen, total phosphorus, water temperature, and water depth played a key role in affecting the growth of P. limnetica, C. raciborskii, M. aeruginosa, and M. wesenbergii. The nitrogen and phosphorus nutrients could promote the growth of harmful cyanobacteria. Due to the good temperature adaptability, P. limnetica could still become the dominant species in early summer and late autumn, and C. raciborskii, M. aeruginosa, and M. wesenbergii had growth advantages when the water temperature was higher than 25℃. In addition, shallow water was more conducive to the growth of C. raciborskii. It was suggested that based on strengthening of the control of nitrogen and phosphorus nutrient input in lakes and reservoirs, the key monitoring of P. limnetica in lakes should be conducted in early summer and late autumn, and the growth of C. raciborskii in shallow water areas should be paid close attention in the high temperature period to ensure the safety of water quality.

[Adverse health effects of cadmium and related factors].

Cd is a very toxic chemical to animal and human beings. Cd contamination has been ubiquitous because of industry and the human activities. Cd not only affects adversely the growth, yield and quality of crops but also effects on the health of animal and human being. The damage of Cd on bone, kidney, liver, immune and procreation systems as well possible factors that influence Cd absorption, accumulation and damage in the body are summarized in this paper.

Transfer of metals from soil to vegetables in an area near a smelter in Nanning, China.

A field survey was conducted to investigate the metal contamination in soils and vegetables, and to evaluate the possible health risks to local population through foodchain transfer near a smelter in Nanning, southern China. Contamination levels in soils and vegetables with cadmium (Cd), lead (Pb), zinc (Zn) and copper (Cu) were measured, and transfer factors (TF) from soils to vegetable plants and its health risk (risk index, RI) were calculated accordingly. Results showed that both soils and vegetables from villages 1 and 2 (V1 and V2, 1500 m and 500 m from the smelter) were heavily contaminated, compared to a village 50 km from the smelter. Geometric mean of Cd and Pb concentrations in vegetables for V1 and V2, respectively, were 0.15 and 0.24 mg Cd kg(-1) and 0.45 and 0.38 mg Pb kg(-1) (on fresh weight basis). Oral intake of Cd and Pb through vegetables poses high health risk to local residents. Risk indices for V1 and V2, respectively, were 3.87 and 7.42 for Cd, and 1.44 and 13.5 for Pb. The complexity of metal contamination and their health risks are also discussed.

Ecological footprint of Shandong, China.

Ecological footprint has been given much attention and widely praised as an effective heuristic and pedagogic device for presenting current total human resource use in a way that communicates easily to almost everyone since 1996 when Wackernagel and Rees proposed it as a sustainable development indicator. Ecological footprint has been improving on its calculation and still can be a benchmark to measure sustainable development although there are still ongoing debates about specific methods for calculating the ecological footprint. This paper calculates the ecological footprint of Shandong Province, China with the methodology developed by Wackernagel and analyzes the current situation of sustainable development in Shandong.

Cadmium uptake by different rice genotypes that produce white or dark grains.

A pot experiment was conducted to investigate cadmium (Cd) uptake by different rice cultivars that produce white or dark grains. Four cultivars with white grains (hereafter, white rice) and five cultivars with dark colors (hereafter dark rice) were selected for this experiment. Three levels of soil Cd concentrations, background (0), 5 and 10 mg/kg, were used. After harvest, plant biomass, tissue concentrations of Cd, Ca, Fe, Cu and Zn were analyzed. The results showed that Cd concentrations are significantly different between different genotypes, but when comparing the Cd concentrations for the two groups, no significant difference was found. For other divalent cations, Ca concentrations in dark rice were higher than those in white ones (P < 0.001 for shoots, P = 0.037 for roots); Fe concentrations in dark rice were also higher than those in white ones (P = 0.001 either in shoot or root); Zn concentrations in shoot of dark rice were higher than those in white ones, but no significant difference in roots. The total molar concentrations of divalent cations in dark rice were also significantly higher than in white rice. The potential benefit of higher Ca and Fe concentrations in dark rice and similar Cd concentrations in both groups is also discussed in this paper.

[Effects of arbuscular mycorrhizal fungi on the toxicity of chlorothalonil on upland rice (Oryzal sativa L.)].

Upland rice was selected as a host plant in a greenhouse-pot-culture experiment to investigate the effects of chlorothalonil and arbuscular mycorrhizal fungi (AMF) on the growth and oxidative damage under chlorothalonil stress. The plants were grown with three concentrations of chlorothalonil (0, 50 and 100 mg x kg(-1) soil). The results suggested that chlorothalonil inhibited the growth of upland rice and reduced dry weight of upland rice shoot from 2.5 g x pot(-1) to 1.0 g x pot(-1), and the root dry weight was reduced from 0.9 g x pot(-1) to 0.3 g x pot(-1). However, with AMF colonization the dry weight of upland rice was increased to 2.1 g x pot(-1). With 50 mg x kg(-1) chlorothalonil addition, the P uptake was reduced from 3200 microg x pot(-1) to 860 microg x pot(-1), but the AMF colonization could increased the P uptake to 1900 microg x pot(-1). Chlorothalonil induced oxidative stress indicating by the changes in activities of antioxidative enzyme and AMF colonization could alleviate the oxidative stress. These results showed that chlorothalonil induced oxidative stress and inhibited P uptake in upland rice and AMF could decrease the side effects of chlorothalonil by increasing P uptake and decreasing oxidative damages.