Micropollutants and biological effects as control indexes for the operation and design of shallow open-water unit ponds to polish domestic effluent

2021 ◽  
pp. 126306
Author(s):  
Yongkun K. Wang ◽  
Xiaochang C. Wang ◽  
Xiaoyan Y. Ma
2019 ◽  
Vol 48 (4) ◽  
pp. 1037-1046
Author(s):  
Youssif Hussin Abdusalam ◽  
IM Sujaul ◽  
Md Abdul Karim ◽  
MG Salah ◽  
M Idris Ali ◽  
...  

Chini lake water is used as a source of water for domestic, industrial and agriculture. The study was carried out to assess the water quality of the lake and surrounding area. Ten sampling sites were selected representing the open water body in the lake. A total of 14 water quality parameters viz.. temperature, EC, TDS, DO, pH, turbidity. BOD, COD, TSS, PO4, SO4, NH4, NO3 and salinity were measured. The lowest WQI value 77 was recorded at site S4, respectively, which were found to be slightly polluted. Considering the NWQS, temperature 30.04°C, EC 31.42 μS/cm, TDS 19.03 mg/l, NO3 - 0.21 mg/l, SO4 - 0.84 mg/l, PO4 - 0.05 mg/l, TSS 12.03 mg/l and salinity 0.03 ppt are categorized under class I, while DO 6.15 mg/l, pH 6.73, turbidity 4.22 NTU, BOD 1.63 mg/l, COD 19.50 mg/l and NH4-N 0.20 mg/l the lake water quality are categorized under class II. Total coliform was 273, 412, 868, 267, 495, 406, 929, 953, 441 and 398 cfu/100 ml at all S1 - S10 sites, respectively. While E. coli was found 13, 7, 13, 5, 7, 5, 6, 106, 10 and 7 cfu/100 ml, respectively at all S1 - S10 sites. The highest number of both total coliform 953 cfu/100ml and E. coli 106 cfu/100ml were observed at site S8. The sources of coliforms and E. coli pollution were wastes from human and animals and domestic effluent, which might be due to lack of improper sanitation systems and effects of land use from surrounding agricultural area.


2018 ◽  
Vol 26 (3) ◽  
pp. 333-338 ◽  
Author(s):  
R.D. Breckels ◽  
B.W. Kilgour

Nuisance growths of aquatic plants in Canadian surface waters continue to be problematic. Only diquat, a contact herbicide that is used to control many free-floating plants (but is less effective at controlling emergent plants), is registered in Canada for general aquatic use. Other herbicides are currently only permitted under “emergency registration.” Recent emergency registrations have been granted to glyphosate and imazapyr, and these two herbicides are likely candidates to be proposed for full registration for direct application to water in Canada in the foreseeable future. These herbicides have been extensively studied in laboratory conditions and have provided a benchmark for ecotoxicity for a variety of aquatic organisms, yet the inherent toxicity of these herbicides derived from tests does not always translate into their environmental toxicity in natural aquatic ecosystems as the fate (e.g., removal from the water body via binding to sediments and suspended solids, degradation, volatization, etc.) and exposure (i.e., continuous in the laboratory versus “pulsed” in the field) of herbicides in the natural environment is very different from their fate and exposure in laboratories. These differences will likely result in field studies having lower biological effects than laboratory studies, even if the initial exposure concentrations were similar. This review details the current knowledge based on field studies that examine the effects of the direct application of diquat, glyphosate, and imazapyr to aquatic environments on aquatic organisms. The studies of the effects of the aquatic formulations of diquat, glyphosate, and imazapyr that are reviewed here generally found negligible or short-lived impacts on fish and aquatic invertebrates in situ, whereas they found that the application of these herbicides was often beneficial through the physical modification of available habitat (i.e., an increase in open water outweighs any potential toxic effects). Conversely, certain surfactants used to increase herbicide efficacy have been suggested to be more toxic than the herbicide itself. We thus suggest monitoring the effects associated with controlled applications of diquat and other aquatic herbicides including glyphosate and imazapyr and their surfactants, as this would be a means of accumulating information that may guide future uses of herbicides in Canadian waterways.


Author(s):  
K. Shankar Narayan ◽  
Kailash C. Gupta ◽  
Tohru Okigaki

The biological effects of short-wave ultraviolet light has generally been described in terms of changes in cell growth or survival rates and production of chromosomal aberrations. Ultrastructural changes following exposure of cells to ultraviolet light, particularly at 265 nm, have not been reported.We have developed a means of irradiating populations of cells grown in vitro to a monochromatic ultraviolet laser beam at a wavelength of 265 nm based on the method of Johnson. The cell types studies were: i) WI-38, a human diploid fibroblast; ii) CMP, a human adenocarcinoma cell line; and iii) Don C-II, a Chinese hamster fibroblast cell strain. The cells were exposed either in situ or in suspension to the ultraviolet laser (UVL) beam. Irradiated cell populations were studied either "immediately" or following growth for 1-8 days after irradiation.Differential sensitivity, as measured by survival rates were observed in the three cell types studied. Pattern of ultrastructural changes were also different in the three cell types.


2002 ◽  
Vol 69 ◽  
pp. 59-72 ◽  
Author(s):  
Kurt Drickamer ◽  
Andrew J. Fadden

Many biological effects of complex carbohydrates are mediated by lectins that contain discrete carbohydrate-recognition domains. At least seven structurally distinct families of carbohydrate-recognition domains are found in lectins that are involved in intracellular trafficking, cell adhesion, cell–cell signalling, glycoprotein turnover and innate immunity. Genome-wide analysis of potential carbohydrate-binding domains is now possible. Two classes of intracellular lectins involved in glycoprotein trafficking are present in yeast, model invertebrates and vertebrates, and two other classes are present in vertebrates only. At the cell surface, calcium-dependent (C-type) lectins and galectins are found in model invertebrates and vertebrates, but not in yeast; immunoglobulin superfamily (I-type) lectins are only found in vertebrates. The evolutionary appearance of different classes of sugar-binding protein modules parallels a development towards more complex oligosaccharides that provide increased opportunities for specific recognition phenomena. An overall picture of the lectins present in humans can now be proposed. Based on our knowledge of the structures of several of the C-type carbohydrate-recognition domains, it is possible to suggest ligand-binding activity that may be associated with novel C-type lectin-like domains identified in a systematic screen of the human genome. Further analysis of the sequences of proteins containing these domains can be used as a basis for proposing potential biological functions.


1967 ◽  
Vol 56 (1_Suppl) ◽  
pp. S122
Author(s):  
P.-J. Czygan ◽  
D. Krebs ◽  
F. Lehmann ◽  
G. Bettendorf

1974 ◽  
Vol 77 (1_Suppla) ◽  
pp. S315-S354 ◽  
Author(s):  
F. Neumann ◽  
R. von Berswordt-Wallrabe ◽  
W. Elger ◽  
K.-J. Gräf ◽  
S. H. Hasan ◽  
...  

ABSTRACT Two types of so-called "depot contraceptives", long-acting steroids which are of interest for human use, were studied in animals. Norethisterone oenanthate, mainly gestagenic in the human and other species, turned out to be predominantly oestrogenic in rats. This oestrogenicity caused indirectly, via an enhanced hypophysial prolactin secretion, the well-known hypophysial and mammary tumours in rats. Another synthetic gestagen, 4,6-dichloro- 17- acetoxy- 16α-methyl-4,6-pregnadiene-3,20-dione, which might be considered in its biological actions similar to preparations containing chlormadinone acetate or medroxy-progesterone acetate, induced no signs of oestrogenicity in dogs. It is surmised that its gestagenic influence indirectly, and probaby, via an enhanced hypophysial prolactin secretion caused "mammary nodules" in this "non-rodent" species. These studies have born out mainly two facts: A synthetic steroid, norethisterone oenanthate, exerted different biological effects in different species: it was a gestagen in the rabbit, whereas in rats, its predominant influence was oestrogenic. The hypophysial prolactin secretion was enhanced in various species by different mechanisms: in rats, the oestrogenicity caused an increased prolactin plasma level, whereas in dogs, a gestagen with obviously no inherent oestrogenicity, 4,6-dichloro-17-acetoxy-16α-methyl-4,6-pregnadiene-3,20-dione, converted the histological appearance of the anterior pituitary into a condition with a greatly increased number of eosinophils. This histological finding was interpreted as an indicator for a hypersecretion of prolactin. Hence, animal work with "gestagens" has only limited predictive value with respect to their possible effects in the human species. Therefore, inflexible recommendations are not helpful in solving the safety problem of long-acting steroids which affect primarily reproductive processes.


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