持久性有机污染物的植物修复

简要介绍了持久性有机污染物,重点分析了植物对去除环境中持久性有机污染物的修复机制,指出了植物修复技术存在的问题和今后的发展方向。     

Chronic consumption of farmed salmon containing persistent organic pollutants causes insulin resistance and obesity in mice

Background

Dietary interventions are critical in the prevention of metabolic diseases. Yet, the effects of fatty fish consumption on type 2 diabetes remain unclear. The aim of this study was to investigate whether a diet containing farmed salmon prevents or contributes to insulin resistance in mice.

Methodology/Principal Findings

Adult male C57BL/6J mice were fed control diet (C), a very high-fat diet without or with farmed Atlantic salmon fillet (VHF and VHF/S, respectively), and Western diet without or with farmed Atlantic salmon fillet (WD and WD/S, respectively). Other mice were fed VHF containing farmed salmon fillet with reduced concentrations of persistent organic pollutants (VHF/S_-POPs). We assessed body weight gain, fat mass, insulin sensitivity, glucose tolerance, ex vivo muscle glucose uptake, performed histology and immunohistochemistry analysis, and investigated gene and protein expression. In comparison with animals fed VHF and WD, consumption of both VHF/S and WD/S exaggerated insulin resistance, visceral obesity, and glucose intolerance. In addition, the ability of insulin to stimulate Akt phosphorylation and muscle glucose uptake was impaired in mice fed farmed salmon. Relative to VHF/S-fed mice, animals fed VHF/S_-POPs had less body burdens of POPs, accumulated less visceral fat, and had reduced mRNA levels of TNFα as well as macrophage infiltration in adipose tissue. VHF/S_-POPs-fed mice further exhibited better insulin sensitivity and glucose tolerance than mice fed VHF/S.

Conclusions/Significance

Our data indicate that intake of farmed salmon fillet contributes to several metabolic disorders linked to type 2 diabetes and obesity, and suggest a role of POPs in these deleterious effects. Overall, these findings may participate to improve nutritional strategies for the prevention and therapy of insulin resistance.     

The uptake of persistent organic pollutants by plants

In a field experiment, the transfer of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) from contaminated soil to maize (Zea mays L.), sunflower (Helianthus annuus), poplar (Populus nigra × P. maximowiczii) and willow (Salix × smithiana) and the distribution of PCB congeners in maize and sunflower was investigated. The former waste incinerator in Hradec Králové (Czech Republic) was chosen for the experiment. Results of plot screening showed heterogenous contamination by PCBs and PAHs. PCB soil contamination was evidently caused by Delor 106 or Aroclor 1260 stocking and PAH contamination by chemicals containing fluoranthene, benzo/b/fluoranthene, phenanthrene and pyrene. Tested plants were planted on a contaminated field site, in soil contaminated with 1530 μg/kg of total PCBs and 0.138 and 3.42 mg/kg of total PAHs. The results show that maize and sunflower roots accumulated the most PCBs from soil. These plants accumulated hexa- and heptachlorobiphenyl congeners more than tri-, tetra-, and pentachlorobiphenyl congeners. Total concentrations of PAHs in tested plants ranged from 0.096 to 1.34 mg/kg. The highest phenanthrene concentration was found in aboveground biomass of sunflower and the highest concentration of pyrene, in maize roots.     

持久性有机污染物污染及其防治

随着化学工业的快速发展,持久性有机污染物（POPs）的污染愈来愈成为突出的环境问题,对生态和人体健康构成严重威胁。文章从生物学的角度,对POPs的特性、分布和对动物与人体健康的危害等方面作了简要的介绍。对POPs污染与危害,提出了相应的治理措施。     

Viruses as triggers of autoimmunity: facts and fantasies.

Autoimmunity has been proposed as the cause of several human chronic inflammatory diseases, and recent animal studies show that viruses can induce autoimmune disease. These studies demonstrate how viruses might misdirect the immune system, and here we discuss critically the evidence that similar phenomena may lead to human disease.     

微生物降解持久性有机污染物的研究进展与展望

持久性有机污染物（POPs）是伴随着人类工业化发展而产生的合成类污染物,具有高毒性、持久性、长迁移性和高生物富集性等特点,POPs污染物的微生物降解一直是环境科学与技术应用领域的研究热点。微生物降解技术修复POPs污染环境具有无二次污染、成本低、快速简便等优点,拥有广泛的应用前景。本文论述了各种POPs微生物分解代谢的最新研究进展,包括降解性微生物资源以及降解机制。此外,还讨论了计算生物学、合成生物学、基因组学等技术在POPs微生物降解中的潜力和应用,以期为环境中持久性有机污染物的修复提供参考。     

Dietary and toxicity exposure of emerging persistent organic pollutants to human health through consumption of cereal crops from Pakistan

There is a lack of scientific literature regarding the bioaccumulation, dietary, and toxicity exposure of emerging persistent organic pollutants through food crops. The current mini-review presents the dietary intake, spatial distribution pattern, and screening-levels risk assessment of persistent organic pollutants (POPs) in the cereal crops and environmental compartments from Punjab Province, Pakistan. Results of congener specific analysis were in accordance to the previously reported pattern of detected POPs across the globe. Spatial distribution was influenced by the industrial and urban fraction and trend of spatial distribution pattern was observed as follows: industrial/urban areas > industrial/peri-urban areas > agricultural/rural areas. Dietary intake of Organochlorine pesticides (OCPs) via consumption of cereal crops was observed higher and was in accordance to the previously reported levels while human health was at marginal risk to cancer. The results of dietary and toxicity exposure of detected POPs warrant auxiliary devotion in future, to this group of contaminants.     

持久性有机污染物在水生食物网中的传递行为

食物网是持久性有机污染物(POPs)在水生生态系统中传递的重要途径,了解其传递行为与机制是POPs生态暴露风险评价的科学基础。从4个方面展开了讨论和分析:(1)食物网主要特征(营养级和食物链长度)与POPs环境行为的关系;(2)POPs在底栖及底栖-浮游耦合食物网中的环境行为;(3)微食物网对POPs环境行为的作用;(4)食物网的变化对POPs环境行为的影响。主要结论如下:(1)已有研究对水生生物中POPs生物放大作用存在较大争议。一般营养级越高,POPs生物富集性越强,但由于各种生态和生理性质的影响,也存在例外情况。食物链长度与POPs生物富集性呈正相关。(2)POPs通过底栖食物网将沉积物中的POPs向上传递,底栖-浮游食物网的耦合提高了高营养级消费者的暴露风险,目前就POPs在底栖食物网中的生物放大性是否大于浮游食物网存在争议。(3)微生物具有较大的比表面积,是吸附POPs的重要载体。另,沉积物中的微生物通过分解有机质,将POPs释放到水柱中。微生物降解也是环境中POPs脱离环境的重要途径。(4)在内、外压力下,食物网结构和功能发生变化,使物质和能量的传递方向和效率发生改变,并与环境理化性质的变化互相耦合,影响POPs的环境行为。当前研究的重点多集中在POPs在浮游食物网,尤其是高营养级浮游食物网中的环境行为,对POPs在底栖及底栖-浮游耦合食物网和微食物网中环境行为的研究相对缺乏。有关POPs在食物网中环境行为的研究多集中在食物网的某个部分,时间尺度较短,缺乏对POPs环境行为动态变化的研究,未来需深入开展多尺度和多角度的POPs在食物网中环境行为的动态变化研究。新型POPs的生产和使用量不断增加,但有关其在食物网中环境行为的相关分析还较为匮乏,需加强研究。     

Dairy ruminant exposure to persistent organic pollutants and excretion to milk

Human activities produce polluting compounds such as persistent organic pollutants (POPs), which may interact with agriculture. These molecules have raised concern about the risk of transfer through the food chain via the animal product. POPs are characterised by a strong persistence in the environment, a high volatility and a lipophilicity, which lead to their accumulation in fat tissues. These compounds are listed in international conventions to organise the information about their potential toxicity for humans and the environment. The aim of this paper is to synthesise current information on dairy ruminant exposure to POPs and the risk of their transfer to milk. Three major groups of POPs have been considered: the polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), the polychlorobiphenyls (PCBs) and the polycyclic aromatic hydrocarbons (PAHs). The results show that contamination of fodder and soil by these compounds is observed when they are exposed to emission sources (steelworks, cementworks, waste incinerators or motorways) compared with remote areas. In general, soil contamination is considered higher than plant contamination. Highest concentrations of POPs in soil may be close to 1000 ng/kg dry matter (DM) for PCDD/Fs, to 10 000 mg/kg DM for PAHs and 100 μg/kg DM for PCBs. The contamination of milk by POPs depends on environmental factors, factors related to the rearing system (fodder and potentially contaminated soil, stage of lactation, medical state of the herd) and of the characteristics of the contaminants. Transfer rates to milk have been established: for PCBs the rate of transfer varies from 5% to 90%, for PCDD/Fs from 1% to 40% and for PAHs from 0.5% to 8%. The differential transfer of the compounds towards milk is related to the hydrophobicity of the pollutants as well as to the metabolic susceptibility of the compounds.     

A Pooled Analysis of Body Mass Index and Mortality among African Americans

Pooled analyses among whites and East Asians have demonstrated positive associations between all-cause mortality and body mass index (BMI), but studies of African Americans have yielded less consistent results. We examined the association between BMI and all-cause mortality in a sample of African Americans pooled from seven prospective cohort studies: NIH-AARP, 1995–2009; Adventist Health Study 2, 2002–2008; Black Women''s Health Study, 1995–2009; Cancer Prevention Study II, 1982–2008; Multiethnic Cohort Study, 1993–2007; Prostate, Lung, Colorectal and Ovarian Screening Trial, 1993–2009; Southern Community Cohort Study, 2002–2009. 239,526 African Americans (including 100,175 never smokers without baseline heart disease, stroke, or cancer), age 30–104 (mean 52) and 71% female, were followed up to 26.5 years (mean 11.7). Hazard ratios (HR) and 95% confidence intervals (CI) for mortality were derived from multivariate Cox proportional hazards models. Among healthy, never smokers (11,386 deaths), HRs (CI) for BMI 25–27.4, 27.5–29.9, 30–34.9, 35–39.9, 40–49.9, and 50–60 kg/m² were 1.02 (0.92–1.12), 1.06 (0.95–1.18), 1.32 (1.18–1.47), 1.54 (1.29–1.83), 1.93 (1.46–2.56), and 1.93 (0.80–4.69), respectively among men and 1.06 (0.99–1.15), 1.15 (1.06–1.25), 1.24 (1.15–1.34), 1.58 (1.43–1.74), 1.80 (1.60–2.02), and 2.31 (1.74–3.07) respectively among women (reference category 22.5–24.9). HRs were highest among those with the highest educational attainment, longest follow-up, and for cardiovascular disease mortality. Obesity was associated with a higher risk of mortality in African Americans, similar to that observed in pooled analyses of whites and East Asians. This study provides compelling evidence to support public health efforts to prevent excess weight gain and obesity in African Americans.     

Removal of persistent organic pollutants from micro-polluted drinking water by triolein embedded absorbent

A new biomimetic absorbent, cellulose acetate (CA) embedded with triolein (CA-triolein), was prepared and applied for the removal of persistent organic pollutants (POPs) from micro-polluted aqueous solution. The comparison of CA-triolein, CA and granular activated carbon (GAC) for dieldrin removal was investigated. Results showed that CA-triolein absorbent gave a lowest residual concentration after 24 h although GAC had high removal rate in the first 4 h adsorption. Then the removal efficiency of mixed POPs (e.g. aldrin, dieldrin, endrin and heptachlor epoxide), absorption isotherm, absorbent regeneration and initial column experiments of CA-triolein were studied in detail. The linear absorption isotherm and the independent absorption in binary isotherm indicated that the selected POPs are mainly absorbed onto CA-triolein absorbent by a partition mechanism. The absorption constant, K, was closely related to the hydrophobic property of the compound. Thermodynamic calculations showed that the absorption was spontaneous, with a high affinity and the absorption was an endothermic reaction. Rinsing with hexane the CA-triolein absorbent can be regenerated after absorption of POPs. No significant decrease in the dieldrin removal efficiency was observed even when the absorption–regeneration process was repeated for five times. The results of initial column experiments showed that the CA-triolein absorbent did not reach the breakthrough point at a breakthrough empty-bed volume (BV) of 3200 when the influent concentration was 1–1.5 μg/L and the empty-bed contact time (EBCT) was 20 min.     

Estimation of melting points of large set of persistent organic pollutants utilizing QSPR approach

The presence of polyhalogenated persistent organic pollutants (POPs), such as Cl/Br-substituted benzenes, biphenyls, diphenyl ethers, and naphthalenes has been identified in all environmental compartments. The exposure to these compounds can pose potential risk not only for ecological systems, but also for human health. Therefore, efficient tools for comprehensive environmental risk assessment for POPs are required. Among the factors vital for environmental transport and fate processes is melting point of a compound. In this study, we estimated the melting points of a large group (1419 compounds) of chloro- and bromo- derivatives of dibenzo-p-dioxins, dibenzofurans, biphenyls, naphthalenes, diphenylethers, and benzenes by utilizing quantitative structure—property relationship (QSPR) techniques. The compounds were classified by applying structure-based clustering methods followed by GA-PLS modeling. In addition, random forest method has been applied to develop more general models. Factors responsible for melting point behavior and predictive ability of each method were discussed.     

Development of a Culturally Relevant Body Image Instrument among Urban African Americans

Objective: To validate a culturally relevant body image instrument among urban African Americans through three distinct studies. Research Methods and Procedures: In Study 1, 38 medical practitioners performed content validity tests on the instrument. In Study 2, three research staff rated the body image of 283 African‐American public housing residents (75% women, mean age = 44 years), with the residents completing body image, BMI, and percentage body fat measures. In Study 3, 35 African Americans (57% men, mean age = 42) completed body image measures and evaluated their cultural relevance. Results: In Study 1, 97% to 100% of practitioners sorted the jumbled figures into the correct ascending order. The correlation between the body image figures and the practitioners’ weight classifications of the figures was high (r = 0.91). In Study 2, observers arrived at similar ratings of body size with excellent consistency (α = 0.95). Ratings of body image were strongly correlated with participant BMI (r = 0.89 to 0.93 across observers and 0.81 for all participants) and percentage of body fat (r = 0.77 to 0.89 across observers and 0.76 for all participants). In Study 3, body image ratings with the new scale were positively correlated with other validated figural scales. The majority of participants reported that figures in the new body image scale looked most like themselves and other African Americans and were easiest to identify themselves with. Discussion: The instrument displayed strong psychometric performance and cultural relevance, suggesting that the scale is a promising tool for examining body image and obesity among African Americans.     

Relative Body Weight and Self-Esteem among African Americans in Four Nationally Representative Samples

FAITH, MYLES S., ELIZABETH MANIBAY, MEREDYTH KRAVITZ, JOHN GRIFFITH, DAVID B. ALLISON. Relative body weight and self-esteem among African Americans in four nationally representative samples. Obes. Res. 1998;6:430–437. Objective : Obesity is an increasingly common health problem among African Americans, especially women, in the United States. However, limited data are available on the psychological correlates of obesity in this population. This study examined the association between self-esteem and relative body weight (RBW) in four large nationally representative samples of African American individuals. Research Methods and Procedures : Data from The Adolescent Health Care Evaluation Study, The National Longitudinal Survey of Youth, The High School and Beyond, and The National Survey of Black Americans were analyzed. Within each database, regression analyses tested the association between RBW and self-esteem while adjusting for age and sex. Results : In three of the four databases, there was no significant association between RBW and self-esteem. In the only database detecting a statistically significant effect, the magnitude of the effect was small. The combined effects of RBW and its interaction with age and sex accounted for <2% of the variance in self-esteem across databases. Discussion : Results suggest that elevated RBW is not associated with a poorer general self-concept, on average, among African American individuals.