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1.
Could wastewater analysis be a useful tool for China? — A review   总被引:1,自引:0,他引:1  
Analysingwastewater samples is an innovative approach that overcomesmany limitations of traditional surveys to identify and measure a range of chemicals that were consumed by or exposed to people living in a sewer catchment area. First conceptualised in 2001, much progress has been made to make wastewater analysis (WWA) a reliable and robust tool for measuring chemical consumption and/or exposure. At the moment, the most popular application of WWA, sometimes referred as sewage epidemiology, is to monitor the consumption of illicit drugs in communities around the globe, including China. The approach has been largely adopted by lawenforcement agencies as a device tomonitor the temporal and geographical patterns of drug consumption. In the future, themethodology can be extended to other chemicals including biomarkers of population health (e.g. environmental or oxidative stress biomarkers, lifestyle indicators or medications that are taken by different demographic groups) and pollutants that people are exposed to (e.g. polycyclic aromatic hydrocarbons, perfluorinated chemicals, and toxic pesticides). The extension of WWA to a huge range of chemicals may give rise to a field called sewage chemical-information mining (SCIM) with unexplored potentials. China has many densely populated cities with thousands of sewage treatment plants which are favourable for applying WWA/SCIM in order to help relevant authorities gather information about illicit drug consumption and population health status. However, there are some prerequisites and uncertainties of the methodology that should be addressed for SCIM to reach its full potential in China.  相似文献   
2.
When males become more ornamented and reproduce more successfully as they grow older, phenotypic correlations between ornament exaggeration and reproductive success can be confounded with age effects in cross-sectional studies, and thus say relatively little about sexual selection on these traits. This is exemplified here in a correlative study of male fertilization success in a large colony of American barn swallows (Hirundo rustica erythrogaster). Previous studies of this species have indicated that two sexually dimorphic traits, tail length and ventral plumage coloration, are positively correlated with male fertilization success, and a mechanism of sexual selection by female choice has been invoked. However, these studies did not control for potential age-related variation in trait expression. Here, we show that male fertilization success was positively correlated with male tail length but not with plumage coloration. We also show that 1-year-old males had shorter tails and lower fertilization success than older males. This age effect accounted for much of the covariance between tail length and fertilization success. Still, there was a positive relationship between tail length and fertilization success among older males. But as this group consisted of males from different age classes, an age effect may be hidden in this relationship as well. Our data also revealed a longitudinal increase in both tail length and fertilization success for individual males. We argue that age-dependent ornament expression and reproductive performance in males complicate inferences about female preferences and sexual selection.  相似文献   
3.
A method based on regression modeling was developed to discern the contribution of component chemicals to the toxicity of highly complex, environmentally realistic mixtures of disinfection byproducts(DBPs). Chemical disinfection of drinking water forms DBP mixtures.Because of concerns about possible reproductive and developmental toxicity, a whole mixture(WM) of DBPs produced by chlorination of a water concentrate was administered as drinking water to Sprague–Dawley(S–D) rats in a multigenerational study. Age of puberty acquisition,i.e., preputial separation(PPS) and vaginal opening(VO), was examined in male and female offspring, respectively. When compared to controls, a slight, but statistically significant delay in puberty acquisition was observed in females but not in males. WM-induced differences in the age at puberty acquisition were compared to those reported in S–D rats administered either a defined mixture(DM) of nine regulated DBPs or individual DBPs. Regression models were developed using individual animal data on age at PPS or VO from the DM study. Puberty acquisition data reported in the WM and individual DBP studies were then compared with the DM models. The delay in puberty acquisition observed in the WM-treated female rats could not be distinguished from delays predicted by the DM regression model, suggesting that the nine regulated DBPs in the DM might account for much of the delay observed in the WM. This method is applicable to mixtures of other types of chemicals and other endpoints.  相似文献   
4.

Purpose

The role of water in the transmission of infectious diseases is well defined; it may act as a reservoir of different types of pathogens. Enteric viruses can survive and persist for a long time in water, maintaining infectivity in many instances. This suggests the need to include virus detection in the evaluation of the microbiological quality of waters.

Methods

In this study, enteric viruses (enteroviruses and hepatitis A virus (HAV)) were investigated by RT-PCR and coliphages (known as indicators of viral contamination) were enumerated with the double-layer technique agar in effluents and sewage sludge from three Tunisian wastewater treatment plants.

Results and discussion

The molecular detection of enteric viruses revealed 7.7% of positive activated sludge samples for enteroviruses. None of the samples was positive for HAV. Molecular virus detection threshold was estimated to be 103?PFU/100?ml. All samples contained high concentrations of coliphages except those of dry sludge. Reductions in the concentrations of bacteriophages attained by the wastewater treatment plants are of the order of magnitude as reductions described elsewhere. Peak concentrations in raw wastewater were associated with winter rains and suspended materials rate in analysed samples. Our data which is the first in North Africa showed that similar trends of coliphages distribution to other studies in other countries.

Conclusion

No clear correlation between studied enteric viruses and coliphages concentration was proved. Coliphages abundance in collected samples should raise concerns about human enteric viruses transmission as these residues are reused in agricultural fields.  相似文献   
5.
The stock of the catadromous European eel (Anguilla anguilla L.) continues to decline and there is growing evidence that poor health status due to contaminants might be a key element in this decrease. Organic contaminants such as polycyclic aromatic hydrocarbons (PAHs) belong to the major threats to yellow eel in their growth habitat and their metabolites are detectable in the bile. Starting the silvering process eels undergo physiological and morphological changes including cessation of feeding and downstream migration back to their spawning grounds. Reduced feed intake results in a diminishment of bile production and induces accumulation of e.g. PAH-metabolites in bile. Therefore, the aim of the present study was to demonstrate the impact of silvering on biliary PAH metabolite concentrations and to utilize normalization procedures to overcome silvering related accumulation effects of PAH-metabolites in eel bile. We investigated the hydroxyl-metabolites of pyrene (1-OH Pyr) and phenantrene (1-OH Phen) in the bile of different maturation stages of eels (silvering index I-V) from nine German rivers. We detected increasing absolute PAH metabolite levels in bile during the silvering process. The highest rise could be observed at the transition from pre migration stage III to the migrating stage IV, suggesting the onset of cessation of feeding at this stage. A cessation bias in PAH metabolite measurement could be diminished by normalization of absolute values against bile pigments (A380, biliverdin). In conclusion, we demonstrated the impact of silvering on PAH metabolite concentrations in eel bile and present suitable normalization procedures to overcome silvering related accumulation effects. Thus, for a future eel monitoring we recommend (1) to regularly monitor PAH metabolites in bile, (2) to determine silvering index of eel and (3) to normalize PAH metabolite values in bile based on maturation/silvering stages. The knowledge of the silvering stage is mandatory for an unbiased evaluation of PAH contamination of European eel towards an international harmonized eel monitoring program.  相似文献   
6.
The main purpose of a strategic environmental assessment (SEA) is to facilitate the early consideration of potential environmental impacts in decision-making processes. SEA alternative identification is a core issue within the SEA framework. However, the current methods of SEA alternative formulation and selection are constrained by the limited setting range and lack of scientific evaluation. Thus, the current paper attempts to provide a new methodology based on the extension theory to identify a range of alternatives and screen the best one. Extension planning is applied to formulate a set of alternatives that satisfy the reasonable interests of the stakeholders. Extension priority evaluation is used to assess and optimize the alternatives and present a scientific methodology for the SEA alternative study. Thereafter, the urban traffic plan of Dalian City is used as an example to demonstrate the feasibility of the new method. The traffic planning scheme and the environmental protection scheme are organically combined based on the extension theory, and the reliability and practicality of this approach are examined.  相似文献   
7.
Physicochemical characteristics of sediment and benthic communities were studied in the proximity of seven sewage outfalls with differences in flow and wastewater treatment in the Western Mediterranean Sea. Redox potential was the only abiotic parameter which showed a pattern related with distance to outfalls, whereas granulometry, percentage of organic matter, metal concentrations or pH did not show changes related with outfall presence. Benthic community analysis proved to be the most suitable monitoring tool. The results showed that the highest impacted stations corresponded with those closest to outfall with the highest flow and only pre-treatment, whilst a decrease of this tendency was detected in the locations where secondary treatment takes place. Meta-analysis showed a decrease of amphipods and tanaids abundance as well as redox potential, as the indicators with the clearest response to sewage presence.  相似文献   
8.
In rural areas in Bangladesh, groundwater is the principal source of water supply. This underground water is available in considerable amount in shallow aquifers. It is free from pathogenic microorganisms and hence water-borne diseases. In plain lands, other than hilly areas, water supply to 97% rural population comes from tube-wells, which is regarded to be a phenomenal achievement in preserving public health. Besides, a dependable water supply system all throughout the country is offset by two factors: (a) high salinity in surface plus groundwater in coastal areas; (b) want of suitable groundwater aquifers in hilly areas and the high cost of setting up tube-wells due to deep underground water table and stony layers. However, presence of arsenic in underground water now poses a serious threat to the success once made in water supply by setting up of manually operated tube-wells in the village areas—the achievement is now on the brink of total collapse. In about 61 districts out of 64, presence of arsenic exceeds a quantity of 0.05 mg/1, a permissible limit as per Bangladeshi water quality standard. Harvesting rainwater can be a pragmatic solution to this problem, which is common in many places in Sylhet especially in the hilly areas on the north eastern part of the city. This can be an alternative source of drinking water because of availability of rainwater from March to October. Heavy rain occurs from end of May till mid September, which is commonly known as the rainy season. This paper focuses on the possibility of harvesting rainwater in rural communities and thickly populated urban areas of Sylhet. It also demonstrates the scopes of harvesting rainwater using simple and low-cost technology. With setting up of a carefully planned rainwater storage tank, a family can have all of its drinking water from rain. Planned use of rainwater through rainwater harvesting in the roof catchments may fulfill the entire annual domestic water demand of a family in the rural areas of Bangladesh.  相似文献   
9.
Accumulation of organochlorine compounds is well studied in aquatic food chains whereas little information is available from terrestrial food chains. This study presents data of organochlorine levels in tissue and plasma samples of 15 critically endangered Iberian lynx (Lynx pardinus) and other 55 wild carnivores belonging to five species from three natural areas of Spain (Doñana National Park, Sierra Morena and Lozoya River) and explores their relationship with species diet. The Iberian lynx, with a diet based on the consumption of rabbit, had lower PCB levels (geometric means, plasma: <0.01 ng mL−1, liver: 0.4 ng g−1 wet weight, fat: 87 ng g−1 lipid weight) than other carnivores with more anthropic and opportunistic foraging behavior, such as the red fox (Vulpes vulpes; plasma: 1.11 ng mL−1, liver: 459 ng g−1, fat: 1984 ng g−1), or with diets including reptiles at higher proportion, such as the Egyptian mongoose (Herpestes ichneumon; plasma: 7.15 ng mL−1, liver: 216 ng g−1, fat: 540 ng g−1), or the common genet (Genetta genetta; liver: 466 ng g−1, fat: 3854 ng g−1). Chlorinated pesticides showed interspecific variations similar to PCBs. Organochlorine levels have declined since the 80s in carnivores from Doñana National Park, but PCB levels are still of concern in Eurasian otters (Lutra lutra; liver: 3873-5426 ng g−1) from the industrialized region of Madrid.  相似文献   
10.
In 1998, the Agrio and Guadiamar rivers underwent an enormous environmental disaster caused by the rupture of the Aznalcóllar tailings dam and the release of 6 hm3 of pyrite sludge and acidic water. Both rivers run over recent alluvial materials which form a small-sized aquifer which is however important because underground water feeds the flow of the rivers. This work analyzes the state of groundwater 10 years after the spill. Before the dam failure, this aquifer was already contaminated in the zone nearest to the mine, to which the impact of the spill was added. Contamination levels in the alluvial aquifer of the Agrio River have decreased remarkably. However, they are still important, with acidic pH values and high concentrations of toxic elements (maximum values of 16 mg/L of Zn and 15 mg/L of Al). There are also important levels of contamination in the Guadiamar alluvial area closest to the mine, as well as in specific zones located further south. The concentration of toxic elements is mainly controlled by pH. The evolution of contaminant levels show a sharp decrease after the first years following the spill, followed by a subsequent stabilization. It is necessary to take measures for the recovery of the aquifer because, otherwise, groundwater will continue contributing contaminants into the Agrio and Guadiamar rivers.  相似文献   
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