Incorporating bioaccessibility into human health risk assessments of heavy metals in urban park soils.

Contaminants in urban soils can directly pose significant human health risks through oral ingestion, particle inhalation, and dermal contact, especially for children in public parks. Both non-carcinogenic and carcinogenic risks of heavy metals (Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn) were characterized in 40 surface soils (exposed lawns)from 14 urban parks in Xiamen, China. Results based on total metal concentrations may overestimate the actual<br />risks in comparison with oral bioaccessibility assessment that were estimated by a simplified physiologically based extraction test (SBET). After considering the soil-specific bioaccessibility (Cd&gt;Cu&gt;Pb&gt;Mn&gt;Zn&gt;Co~-Ni&gt;Cr), the non-cancer hazard of Pb to children via oral ingestion should be a consideration though its Hazard Index (HI)was below one. The overall cancer risks to adults still exceeded the target value 10&minus;6,mainlycontributed<br />by Cr (93.8%) and Pb (6.19%) via dermal contact (68.3%) and oral ingestion (30.4%). To produce a more realistic estimation<br />for human health risks of metal contamination in urban soils, a framework combining land use type and bioaccessibility is recommended and thereby should be applied for the derivation of risk-based, site-specific soil guidelines

Phthalates exposure of Chinesereproductiveagecouples and its effect on male semen quality, a primary study

<p id="sp0065">Phthalates are suspected of having adverse effects on androgen-regulated reproductive development in animals and may be toxic for human sperm. The purposes of our study were to investigate the general exposure of a Chinese reproductive age cohort to these ubiquitous pollutants and to assess their potential effect on semen quality.</p><p id="sp0070">Six phthalate metabolites, monomethyl phthalate (MMP), monoethyl phthalate (MEP), monobutyl phthalate (MBP), monobenzyl phthalate (MBzP), mono-2-ethylhexyl phthalate (MEHP), and mono-2-ethyl-5-oxohexyl phthalate (MEOHP) were measured in spot urines of 150 individuals recruited from a Chongqing, China, reproductive institute. The questionnaire and clinical data were evaluated, and the correlations of phthalate exposure and semen qualities like semen volume, sperm concentration, motility and sperm motion parameters, were determined by multiple logistic regression analysis.</p><p id="sp0075">The creatinine adjusted average concentrations for MMP, MEP, MBP, MBzP, MEHP and MEOHP were 41.3, 300, 41.0, 0.78, 2.99 and 3.90&nbsp;&mu;g/g, respectively. After adjustment for age, body mass index (BMI), abstinence, smoking, drinking, and education, there was a borderline-significant dose&ndash;response relationship between MBP and sperm concentration, with odd ratios (ORs) 1.0, 6.8 and 12.0 for increasing exposure tertiles (<em>p</em>&nbsp;=&nbsp;0.05). Although the dose&ndash;response relationships for MMP and MEP versus sperm concentration were not significant, a significant positive correlation between MEP and straight-line velocity of sperm motion was observed.</p><p id="sp0080">The present data may imply some effects of phthalate exposure on semen. However, due to the small sample size, our finding needs to be confirmed on a larger population.</p

Using material/substance flow analysis to support sustainable development

The essence of sustainable development (SD) is to deliver social and economic development without compromising environmental quality. Material Flow Analysis or Substance Flow Analysis (M/SFA) is a well-established method to assess the sustainability of socioeconomic development and environmental change, particularly from the perspective of improving material/substance flow efficiency. A material/substance flow chart or accounting table makes SD assessment results comprehensive, comparable and verifiable by (1) providing systematic information and indicators for SD assessment, (2) identifying critical pathways, links and key substances in the anthroposphere, and (3) allowing the dynamic interaction between material flow and social, economic and/or environmental processes to be analyzed. However, the role of M/SFA in SD assessment could be expanded by strengthening simultaneous analysis of various features of material/substance flows, integrating M/SFA with other assessment methods, improving sustainability indicators, and further developing standardized methods for material classification, data acquisition and processing, and measuring indirect flows and unused flows. It is anticipated that future improvements in monitoring material/substance flows in the anthroposphere will provide more systematic information, allowing M/SFA to play an even greater role in SD assessment

Complementary zoning frameworks for sustainable management of eco-economic capital: a case study of Lijiang, China

We propose two zoning frameworks for<br />regional decision-makers to regulate eco-economic<br />capital in Lijiang, southwest China, using an index<br />system, layer overlay, and GIS spatial analysis. The<br />frameworks include eco-economic zoning and major<br />function-oriented zoning, with an emphasis on ecoeconomic<br />capital and human activities. The two<br />frameworks share common advantages in top-down<br />resource regulation by a certain function and the<br />pursuit of competitiveness, sustainability and welfare<br />fairness. Their differences in development orientation,<br />functional links and scale suitability provide a<br />complementary approach for regional decisionmakers.<br />The frameworks will help to understand<br />complex eco-economic resource patterns and foster<br />appropriate regional regulation strategies

Effect of silver loaded sodium zirconium phosphate (nanoAgZ) nanoparticles incorporation on PES membrane performance.

Polyethersulfone (PES) based ultrafiltration membranes were fabricated via phase inversion by adding silverloaded sodium zirconium phosphate nanoparticles (nanoAgZ) in PES casting solutions. The effect of nanoAgZ concentration on the membrane performance, i.e., morphology, hydrophilicity, thermal stability, permeation and antifouling properties was investigated. The results of thermal gravitational analysis (TGA) showed that<br />the thermal stability of the hybrid membrane had been improved by the addition of nanoAgZ particles. Contact angle results indicated that the hydrophilicity of the modified membranes was enhanced. The contact angle of the membrane decreased from 71.5&deg; to 52.6&deg; with the increase of the nanoparticle content in the<br />casting solution. Permeation experiment results showed that the modified PES membranes demonstrate better separation performance over the pure PES membrane. The pure water flux of PES membrane increased from 82.1 L/m2 h to 100.6 L/m2 h with the addition of the nanoparticles. Most importantly, the incorporation of the nanoAgZ particles enhanced the BSA fouling resistance and also the anti-biofouling performance of the<br />membrane

Urban Thermal Landscape and Landscape of Urban Heat Island: A Comparative Study of Urban Thermal Patterns from the View of Landscape Ecology

Thermal landscape has been proved quite useful and valuable in assessing dynamics and driving forces of urban heat island (UHI). With its prevalence, several key problems have come forth as how to make out its extent when study cities. To investigate the differences between urban thermal landscape and landscape of UHI, a comparative study was carried out in Xiamen using a 20-year winter time-serial Landsat images. Two schemes of landscape extent settings were taken, for landscape metrics calculation and analysis. The results showed that, the landscape metrics dynamics of urban thermal landscape and UHI were quite consistent with each other at class level during the process of urbanization. While at landscape level, the choice between the two schemes would affect the evolvements of shape complexity, contagion, diversity and evenness obviously by shifting the position of turning points at most time. This must be paid attention when investigating the dynamics of thermal patterns in cities, in that it might lead to different conclusions and decisions

Arsenate toxicity and stress responses in the freshwater ciliate Tetrahymena pyriformis

The arsenic metabolism in different biological organisms has been studied extensively. However, little is known about protozoa. Herein, we investigated the cell stress responses of the freshwater ciliate <em>Tetrahymena pyriformis</em> to arsenate toxicity. An acute toxicity assay revealed an 18-h EC_{<font size="2">50</font>} arsenate concentration of ca. 40&nbsp;&mu;M, which caused significant changes in the cell shape, growth and organism mobility. Whereas, under exposure to 30&nbsp;&mu;M arsenate, <em>T. pyriformis</em> could grow reasonably well, indicating a certain resistance of this organism. Arsenic speciation analysis revealed that 94&ndash;98% of the total arsenate in cells of <em>T. pyriformis</em> could be transformed to monomethylarsonic acid, dimethylarsinic acid and a small proportion of arsenite after 18&nbsp;h of arsenate exposure, thus indicating the major detoxification pathway by arsenic oxidation/reduction and biomethylation. Finally, comparative proteomic analysis unveiled significant changes in the expression of multiple proteins involved in anti-oxidation, sugar and energy metabolism, proteolysis, and signal transduction. Our results revealed multiple pathways of arsenate detoxification in <em>T. pyriformis</em>, and indicated that protozoa may play important roles in the biogeochemical cycles of arsenic