Hexabromocyclododecane-induced Genotoxicity in Cultured Human Breast Cells through DNA Damage / 生物医学与环境科学（英文）

To investigate the genotoxicity and reveal the potential toxicological mechanisms of Hexabromocyclododecane (HBCD), human breast cells HBL-100 were exposed to a sequence of HBCD concentrations (0, 5, 10, and 50 mg/L) for 24 h. With a series of zymology and molecular biology methods, we found that HBCD induced dose-dependent oxidative stress on HBL-100 DNA. As revealed in qRT-PCR, activated prognostic factor ATM down-regulated tumor suppressor gene BRCA1 and prompted DNA repair genes hOGG1 and hMTH1 expression in lower concentrations of HBCD (< 10 mg/L). However, DNA repair were inhibited as well as cell proliferation rate by higher concentrations of HBCD (50 mg/L). The results inferred that the genotoxicity of HBCD was dose-dependent and related to DNA repair pathway.

Subacute effect of decabromodiphenyl ethane on hepatotoxicity and hepatic enzyme activity in rats / 生物医学与环境科学（英文）

Information regarding decabromodiphenyl ethane (DBDPE) effects on hepatotoxicity and metabolism is limited. In the present study, Wistar rats were given oral DBDPE at different doses. DBDPE induced oxidative stress, elevated blood glucose levels, increased CYP2B2 mRNA, CYP2B1/2 protein, 7-pentoxyresorufin O-depentylase (PROD) activity, and induced CYP3A2 mRNA, CYP3A2 protein, and luciferin benzylether debenzylase (LBD) activity. UDPGT activity increased with its increasing exposure levels, suggesting that oral DBDPE exposure induces drug-metabolizing enzymes in rats via the CAR/PXR signaling pathway. The induction of CYPs and co-regulated enzymes of phase II biotransformation may affect the homeostasis of endogenous substrates, including thyroid hormones, which may, in turn, alter glucose metabolism.

Analytical study on the RoHS of plastic from waste electrical and electronic appliances

This study was conducted to identify emission characteristics of certain hazardous substances contained in the plastic of used home electrical and electronic appliances keeping in view compliance with the Restriction of Hazardous Substances [RoHS] Directive and to estimate the possibility of safe recycling practices. According to the results, the concentration of cadmium, lead, mercury and chromium were found below than Maximum Concentration Value [MCV] of RoHS, while the concentration of total bromine [T-Br] was exceeded the standard limitations in the samples of plastic from e-waste. Over 90% of the plastics used in housing cover of display electronic products were composed of Polystyrene [PS] 53.9% and PS-flame retardants 36.4%.Peak of each hazardous substance in total samples also showed higher values of bromine, cadmium and lead. In order to enhance cleaner recycling of waste electronic appliances in accordance with the allowance of RoHS Directive, the use of brominated flame retardants in plastic and chrominated synthetic resins should be restricted and applications of metal surface finishing such as coating and painting of high molecules synthetic resins should be minimized

Mouse sperm DNA damage induced by exogenous BDE-209 / 南方医科大学学报

<p><b>OBJECTIVE</b>To assess the DNA damage in mouse sperms induced by exogenous BDE-209 and explore the possible mechanism of BDE-209 in affecting normal zygote development.</p><p><b>METHODS</b>Mouse sperms were harvested from the epididymal tail and suspended in HTF medium for a 90-min exposure to BDE-209 at varied concentrations of 0, 2.5, 5.0, 10, and 20 µg/ml (groups A-E, respectively). After the exposure, the sperms were subjected to single-cell gel electrophoresis (SCGE) to assess the DNA damage.</p><p><b>RESULTS</b>The tail length of the sperms averaged 1.15 ∓ 1.27 µm in group A. Exposure to 10 and 20 µg/ml BDE-209 resulted in a significant lengthening of the sperm tails (2.13 ∓ 1.29 µm and 2.83 ∓ 2.46 µm, respectively, P<0.01) as well as increased DNA content in the tail of the cells (P<0.01). The Olive tail moment in group A was 0.270 ∓ 0.322, and increased after BDE-209 exposure to 0.453 ∓ 0.375 and 808 ∓ 0.822 in groups D and E, respectively. The tail/head length ratio in groups C, D, and E (0.077 ∓ 0.093, 0.112 ∓ 0.068, and 0.191 ∓ 0.207) were significantly greater than that in group A (0.045 ∓ 0.049). The DNA damage of the mouse sperms was directly correlated to the concentrations of BDE-209, with correlation coefficients all above 0.9.</p><p><b>CONCLUSIONS</b>Exogenous BDE-209 can cause mouse sperm DNA damage and lead to sperm DNA chain breakage, and this effect shows an obvious dose dependence.</p>

Simultaneous determination of melamine, ammelide, ammeline, and cyanuric acid in milk and milk products by gas chromatography-tandem mass spectrometry / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To develop an analytical method for simultaneously qualitative and quantitative determination of melamine and triazine-related by-products including ammelide, ammeline, and cyanuric acid in milk and milk products by gas chromatography-tandem mass spectrometry (GC-MS/MS).</p><p><b>METHODS</b>Melamine and triazine-related by-products namely ammelide, ammeline and cyanuric acid in the samples were extracted in a solvent mixture of diethylamine, water, and acetonitrile (10:40:50, V/V/V). After centrifugation, an aliquot of the supernatant was evaporated to dryness under a gentle stream of nitrogen gas, and then melamine and triazine-related by-products were derivatized using BSTFA with 1% TMCS. The derivatives of melamine and its analogues were determined by gas chromatography/tandem mass spectrometry using multiple reactional monitoring (MRM) with 2, 6-Diamino-4-chloropyrimidine (DACP) being used as an internal standard.</p><p><b>RESULTS</b>The linear detectable ranges were from 0.004 mg/kg to 1.6 mg/kg for melamine, ammelide, ammeline, and cyanuric acid with a correlation coefficient no less than 0.999. The recovery rates of the four compounds in spiked blank milk powder at concentrations 0.5, 1, 2 mg/kg were between 61.4%-117.2%, and the relative standard deviation was no more than 11.5% (n=6). The detection limits of melamine, ammelide, ammeline and cyanuric acid in milk powder were 0.002 mg/kg with a ratio of signal to noise of 3.</p><p><b>CONCLUSION</b>This GC-MS/MS method for simultaneous determination of melamine, ammelide, ammeline, and cyanuric acid in milk and milk products is sensitive and specific.</p>

A survey on occurrence of melamine and its analogues in tainted infant formula in China / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the occurrence and concentrations of melamine and its analogues in tainted infant formula and to identify the etiologic factors for the urinary stones epidemic in infants and young children in China in 2008.</p><p><b>METHODS</b>Sanlu infant formula samples were collected from families of the affected children in Gansu province, and markets in Gansu and Hebei provinces and Beijing city. Melamine and its analogues, including cyanuric acid, ammeline, and ammelide were measured by gas chromatography/tandem mass spectrometry.</p><p><b>RESULTS</b>High prevalence and concentrations of melamine were found in Sanlu infant formula samples, with low concentrations of cyanuric acid, ammeline and ammelide. Melamine were detected in 87 out of 111 Sanlu infant formula samples with a range of 118 to 4,700 mg/kg.</p><p><b>CONCLUSION</b>The results provide strong evidence for melamine as the etiological factor for the urinary stones epidemic in infants and young children in China in 2008.</p>

Assessment on dietary melamine exposure from tainted infant formula / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To estimate the dietary melamine exposure in Chinese infants and young children from the consumption of melamine adulterated Sanlu infant formula.</p><p><b>METHODS</b>Four age groups of infants and young children (3, 6, 12, and 24 months) were chosen as the assessed subjects and the maximum amount of infant formula consumption was estimated based on the recommended usage level in the package insert of Sanlu infant formula and other brands. Melamine was analyzed in 111 Sanlu infant formula samples collected from the markets in Beijing and Gansu province using the LC-MS-MS with a limit of quantification of 0.05 mg/kg. Four levels of melamine concentration were chosen to estimate the dietary intakes, including the mean, median, 90th percentile, and maximum.</p><p><b>RESULTS</b>The infants of 3 months had the highest intake of melamine, and with the increase of the age (month), the intake decreased. Based on the median melamine concentration (1,000 mg/kg) as an example, the melamine intakes for the infants of 3, 6, 12, and 24 months were 23.4, 21.4, 15.0, and 8.6 mg/kg bw/d, respectively.</p><p><b>CONCLUSION</b>Dietary melamine intakes from tainted Sanlu infant formula significantly exceeded the TDI level (0.2 mg/kg bw/d) recommended by the WHO Expert Meeting in 2008. However, the present assessment has some limitations including the poor representative samples, the varied melamine concentrations in the adulterated Sanlu infant formula, and other brand infant formula possibly consumed by these infants.</p>

Transient and spatial modeling and simulation of polybrominated diphenyl ethers reaction and transport in air, water and soil

The release of the wastes containing polybrominated diphenyl ethers into the environment is a worldwide major concern. Investigation of spatial and temporal variations of polybrominated diphenyl ethers concentrations due to different factors, especially the transport of these species between air and water as well as between air and soil is the purpose of present research. A model was developed and solved using the methods of finite difference and lines. Simulations were implemented for three dimensions of width, length, and height and also time for the air compartment, whereas for the soil and water compartments, variations were considered only with respect to height and time. Transport between water and soil was disregarded for simplicity at this stage. Vancouver's landfill was considered as a case study. Lower concentrations in air and higher concentrations in water at the interface show that these pollutants tend to diffuse from air to water. Concentrations of all four pollutants decrease near the interface in soil as time passes, but they are predicted to be almost constant at other levels

Estudio preliminar sobre los niveles de exposición a PBDES en sangre y leche materna en México / Exposure levels of PBDES in blood and breast milk in Mexico, a preliminary study

Los retardantes de flama bromados han sido muy usados en las últimas décadas en muchos productos de consumo. Su producción, uso, lipofilicidad y persistencia, los han vuelto contaminantes ambientales ubicuos. Han sido detectados en el ser humano en varios países y poco se conoce sobre susefectos tóxicos. El propósito de este estudio fue determinar de manera preliminar los niveles de exposición a difeniléteres polibromados (PBDEs) en la población mexicana. Se tomaron muestras de sangre a 5 mujeres de una zona urbana y muestras de leche materna a 7 de una zona rural. Los niveles de PBDEs en las mujeres de la zona urbana fueron de 21.5-37.5 ng/glípido y los de las mujeres rurales fueron 0.8-5.4 ng/g lípido.

The brominated flame retardants have been used in the last decades inmany products. Their production, use, lipofilicity and persistence, make them ubiquituos in the environment. They have been detected in humans in several countries and little is known about their toxics effects. The aim of this pilot study was to determine exposure levels of polybrominated diphenylethers (PBDEs) in the Mexican population, blood samples were taken from five women living in an urban area, whereas breast milk samples were collected from seven rural women. The levels of PBDEs in theurban area were 21.5-37.5 ng/g lipid; whereas milk concentrations in rural women were 0.8-5.4 ng/glipid.

Impact of PBDE-209 exposure during pregnancy and lactation on immune function of offspring rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To assess the potential hazard of environmental deca-brominated diphenyl ether (PBDE-209) exposure to the immune function of the offspring rats.</p><p><b>METHODS</b>The parental Wistar rats were exposed to PBDE-209 administered intragastrically during pregnancy and lactation, and the development of the immune organs and changes in T lymphocyte subset and their proliferation, NK cell surface markers CD161 and serum immunoglobulins (IgM and IgG) were observed.</p><p><b>RESULTS</b>Significant differences in the weight of the immune organs were noted between the exposure group and control group. In the exposure group, the percentage of T lymphocyte subset CD3(+), CD4(+), CD8(+), CD4(+)CD8(+), the percentage of NK cell surface markers CD16 1 and CD4(+)/CD8(+) ratio were lowered, while the percentage of CD4(-)CD8(-) cells increased. T lymphocyte subset proliferation in the exposure group did not show obviously changes, but compared with the control group, the IgM level in the exposure group was significantly lowered. No significant differences were observed in IgG levels between the exposure and control groups.</p><p><b>CONCLUSION</b>Continuous exposure to high-dose PBDE-209 in female rats during pregnancy and lactation results in possible adverse effect on the immune function of the offspring rats.</p>

Chemical modification of acrylic fibres to improve some of their properties [A Review Article]

This review is given to illustrate and interpret some modifications acrylic fibers to attain better properties. Improvements of fire resistance, heat stability, dyeability, antimicrobial, moisture regain and conductivity properties are reported. Improvements of the aforementioned properties give the fibres an important position in the textile industry. The modified fibres became more convenient in different uses

Some chemical data on cyperus papyrus L. the ancient paper making material

Papyrus can indeed be considered as a plant that touched the Egyptian civilization at many points. It is of interest that [Papyrus Paper] is still being made for sale to tourists. Most of the studies made on various species of papyrus have been concerned with the pulping operations in order to find their potential as a paper making material. Various types of pulping have been reported the most satisfactory of which was that using sodium hydroxide. However, the yield from such alkaline pulping was rather low. Recently, it was found that the paper made from Papyrus without treatment with fire retardants has better fireproofing than other papers. On the other hand, its treatments with fire retardants did not significantly improve its flammability properties. Consequently, it was suggested that Papyrus has an inherent flame-retardant effect. A systematic study of the constituents and chemistry of the various species of Papyrus are rather few. The presence of D-fructose and D-glucose was reported in the hot water extract of the parenchymatous tissue of Cyperus papyrus, together with xylose and small amounts of glucosan from the products of hydrolysis of the same tissue after water extraction. Although, an analytical study of the rind and pith of the Papyrus has been reported it was found later that the study has been undertaken on another plant. Consequently, it is of interest to do such a study on the pith and rind of Egyptian Papyrus [Cyperus papyrus L.]

Manual de protección contra el fuego / Manual of protection against the fire

El presente manual ha sido elaborado en base de experiencia vividas tanto por lo bomberos de paises hermanos,así como el personal de bomberos de la policia nacional de Bolivia.Con el propósito de brindar bibliografía a todas aquellas personas de escasos recursos económicos que tienen poca posibilidad de acceso a este tipo de información,finalmente a la sociedad en su conjunto