Zinc contents in foods and estimates of dietary intakes in Guangzhou, Guangdong Province, China.

Zinc is one of human essential metals. In this study, 101 kinds of daily food for residents, including vegetables, aquatic food, meat, fruits, rice and cereal products, pulse food, dairy products and eggs, were collected at various agricultural markets and supermarkets in Guangzhou city, China, and their zinc contents were determined. The results showed oyster is most abundant in zinc (703.5 ± 25.6 mg/kg), followed by high-zinc milk powder (58.63 ± 0.90 mg/kg), pulse food, mutton, beef and pig liver with zinc contents above 30 mg/kg. The zinc contents of rice and cereal products, milk powder, poultry, pork, some aquatic food and eggs are also relatively high (>10 mg/kg), while vegetables and fruits have zinc contents significantly below 10 mg/kg. The daily zinc intake per person was determined by considering the zinc content of various food types and the dietary habits of specific demographic groups, resulting in 12.3 mg/day for the normal person, 11.2 mg/day for low-income individual, 12.3 mg/day for middle-income individual, 13.3 mg/day for high-income individual, 10.2 mg/day for older individual, 12.9 mg/day for factory worker, 11.5 mg/day for college student, and 8.4 mg/day for kindergarten child. The reference values of zinc intake recommended by the Chinese Nutrition Society were used to evaluate the zinc intake of Guangzhou residents, showing that the residents' zinc intake is generally sufficient and not necessary to use zinc supplementation. Income, age and occupation could have posed influence on dietary intake of zinc.

Wet scrubber coupled with heterogeneous UV/Fenton for enhanced VOCs oxidation over Fe/ZSM-5 catalyst.

The traditional treatment processes for volatile organic compounds (VOCs) removal generally suffered several disadvantages, such as secondary air-pollutants. To overcome these issues, wet scrubber coupled with heterogeneous UV/Fenton was developed for gaseous VOCs (i.e. toluene) removal. ZSM-5 supported iron oxide (Fe/ZSM-5) was prepared as a multifunctional catalyst for activation of H2O2 and enhancement of gas-liquid mass transfer. Toluene was removed efficiently by this coupled process with the removal efficiency of 85% during 120 min. Many intermediates were detected in the solution by GC-MS while no intermediates were observed in the outlet gas, suggesting that wet scrubber coupled with heterogeneous UV/Fenton could significantly reduce secondary air pollutants. The possible mechanism of toluene oxidation was proposed including the physical adsorption by Fe/ZSM-5 and OH oxidation. This study provides an environmentally benign and highly efficient chemical scrubbing process for gaseous VOCs removal.

Impacts of Atmospheric Mercury Deposition on Human Multimedia Exposure: Projection from Observations in the Pearl River Delta Region, South China.

A preliminary projection was performed to determine human multimedia exposure to mercury (Hg) based on deposition flux observations and to identify the impacts of atmospheric Hg deposition in Pearl River Delta (PRD) region, South China. The Monte Carlo technique was used to propagate the variability throughout the projection. The regional specific probability density functions (PDFs) of the studied parameters were regressed from the provincial/national published data, except when the data were deficient. The atmospheric Hg deposition flux ranged from 43.70 to 321.19 µg/m2/year and did not significantly contribute to Hg accumulation in the regional topsoil, freshwater bodies, and most food items except fish. The consumption of fish and milk/dairy products was the major contributor to the total exposure for adults (>18 years)/6- to 12-year children and 0- to 6-year children, respectively. The projected concentrations and exposure levels were the results combining MeHg and inorganic Hg (Hg2+). Under the 30-year projection, the probability of risks caused by Hg deposition (combining Hg2+ and MeHg) was the highest for 0- to 6-year children, followed by 6- to 12-year children and adults. The ground effects driven by precipitation had a significantly greater effect relative to the mass transport effects in this region.

Hydroxysafflor yellow A attenuates carbon tetrachloride-induced hepatic fibrosis in rats by inhibiting ERK5 signaling.

Hepatic stellate cells (HSCs) undergo activation during the development of liver fibrosis. Transcription factor myocyte enhancer factor (MEF2) 2C plays a key role in this process. In the present study, we investigated the effect of hydroxysafflor yellow A (HSYA) on hepatic fibrosis and further investigated potential mechanisms in vivo. Sprague-Dawley rats were administered with CCl(4) together with or without HYSA for 12 weeks. The effect of HYSA on hepatic fibrosis was evaluated using hematoxylin-eosin and Van Gieson staining. Messenger RNA expression was quantified by real-time polymerase chain reaction, and protein was quantified by Western blot or immunohistochemistry. Our results revealed that CCl(4) treatment induced micronodular hepatic fibrosis with a pronounced deposition of collagen fibers. Treatment with HYSA resulted in a significant decrease in fibrosis, protein expression of α-SMA, and MEF-2C gene expression. This was accompanied by a decreased expression of Tß-RI, Tß-RII, MEKK3, MEK5, and phosphorylation of ERk5. HYSA alone had no effect on the measured parameters. Our findings demonstrate that HSYA protected, at least in part, the rat liver from CCl(4)-caused fibrogenesis through inhibition of hepatic stellate cell (HSC) activation, attenuation of transforming growth factor beta (TGF-ß) signaling. HSYA may become a novel and promising agent for the inhibition of hepatic fibrosis.

Hydroxysafflor yellow A protects against chronic carbon tetrachloride-induced liver fibrosis.

Hydroxysafflor yellow A (HSYA) was isolated from the dried flower of Carthamus tinctorius L. which was extensively used in traditional Chinese medicine to treat cirrhosis. However, the potential protective effect of HSYA in liver fibrosis is still unknown. In the present study, we investigated the effects of HSYA in rats with carbon tetrachloride (CCl4)-induced liver fibrosis. Sprague-Dawley (SD) rats were subjected to biweekly CCl4 injections over 12 weeks, while controls were given isovolumetric injections of olive oil. HSYA was given in a daily dose of 5 mg/kg by means of intraperitoneal concurrent with CCl4. Hepatic fibrosis was quantified by digital analysis of Masson's trichrome stained slides and hydroxyproline content. mRNA expression was quantified by real-time polymerase chain reaction (PCR), and protein was quantified by western blot or enzyme-linked immunosorbent assay (ELISA). CCl4 treatment induced micronodular liver fibrosis with a pronounced deposition of collagen fibers. HSYA significantly reduced liver fibrosis. HSYA down regulates α-smooth muscle actin (SMA), collagen α type I, matrix metalloproteinases (MMP)-9, and tissue inhibitors of metalloproteinases (TIMP)-1 gene expression. This was accompanied by a decreased expression of transforming growth factor (TGF)-ß1 and phosphorylation of Smad4. These results indicate that HSYA might be a promising antifibrotic agent in chronic liver disease.

A novel wet-scrubbing process using Fe(VI) for simultaneous removal of SO2 and NO.

The objective of this work was to develop a novel wet-scrubbing process using Fe(VI) for the simultaneous removal of gaseous NO and SO(2). The oxidation of SO(2) and NO with Fe(VI) was studied in aqueous solution at alkaline pH (9.0-11.0). A stoichiometric molar ratio for NO and SO(2) oxidation with Fe(VI) was determined to be nearly 3.0. Sulfate and nitrate was identified as final products by ion chromatography from the reaction at pH 9.0-11.0. The feasibility of simultaneous removal of multiple gas pollutants with the continuous feeding of ferrate in lab-scale was investigated from the view of industrial application. It was found that the removal efficiency of NO and SO(2) was enhanced with the increase of Fe(VI) concentration, more than 90% NO removal efficiency and 100% SO(2) removal efficiency were achieved by wet-scrubbing process using Fe(VI) at room temperature and ambient atmosphere. The results demonstrate that Fe(VI) could be an effective wet-scrubbing agent for the simultaneous removal of NO and SO(2).

The study of operating variables in soil washing with EDTA.

This study discusses the operating variables for removal of metals from soils using EDTA, including the type of EDTA, reaction time, solution pH, dose, temperature, agitation, ultrasound and number of extractions. For As, Cd, Cu, Pb and Zn, the removal efficiency order was: H(4)-EDTA > Na(2)EDTA > (NH(4))(2)EDTA. At low EDTA concentrations the removal increased progressively with increasing dose while above 0.4 mmol/g only small increases in extraction efficiency were observed. EDTA induced a two-step process including a rapid desorption within the first hour, and a gradual release in the following hours. The extraction efficiency of metals decreased with increasing pH in the range of 2-10. Consecutive extractions using low concentrations were more effective than a single extraction with concentrated EDTA if the same dose of EDTA was used.

[Food selenium content and resident daily selenium intake in Guangzhou City].

The investigation on the food selenium content in Guangzhou City of Guangdong Province showed that viscera of animal foods, aquatic products, eggs, and mutton were abundant with selenium ( > 150.0 microg x kg(-1)), followed by cereals and beans (46.5-98.3 microg x kg(-1)), vegetables (15.8 microg x kg(-1)), and fruits (4.97 microg x kg(-1)). Among vegetable foods, mushroom had the highest selenium content (46.0 microg x kg(-1)). The daily selenium intake of residents in Guangzhou was 98.5 microg, in which, 73.7% was contributed by animal foods, and 26.3% was from vegetable foods. Aquatic products, pork and rice contributed 24.8%, 22.3% and 17.2%, respectively. The food selenium content and resident daily selenium intake in Guangzhou could meet the demand of human health in the City.