Distribution and Estrogenic Risk of Alkylphenolic Compounds, Hormones and Drugs Contained in Water and Natural Surface Sediments, Morelos, Mexico

This study evaluated the distribution and potential estrogenic risk of the presence of bisphenol A (BPA), 4-nonylphenol (4NP), naproxen (NPX), ibuprofen (IBU), 17-β-estradiol (E2) and 17-α-ethinylestradiol (EE2) in water and sediments of the Apatlaco river micro-basin (Morelos, Mexico). The concentration of the determined compounds ranged between <LOD to 86.40 ng·L−1 and <LOD to 3.97 ng g−1 in water and sediments, respectively. The Log Kd distribution obtained (from 1.05 to 1.91 L Kg−1) indicates that the compounds tend to be adsorbed in sediments, which is probably due to the hydrophobic interactions confirmed by the significant correlations determined mainly between the concentrations and parameters of total organic carbon (TOC), total suspended solids (TSS), biological oxygen demand (BOD5) and chemical oxygen demand (COD). Of five sites analyzed, four presented estrogenic risk due to the analyzed endocrine-disrupting compounds (EEQE2 > 1 ng·L−1).

EFFECTS OF DREDGING ON DOWNSTREAM WATER QUALITY: EKOLE CREEK, NIGERIA

Water is essential part of ecosystem, so its quality must be ascertained for use especially in Ekole creek of Nigeria where dredging activities is heavy, hence this study examined the dredging effect on the downstream water quality of Ekole creek. Water samples were collected from four points which are; Upstream, Dredge I, Dredge II, and Downstream points. The parameters of the water quality determined showed that Turbidity and Total Suspended Solids (TSS) were higher at the Downstream point with values of 31 NTU and 1664 mg/l respectively; pH was also slightly acidic (6.61); but low in Total Dissolve Solid (TDS), Electrical Conductivity, Nitrate (NO3) and Dissolved Oxygen (DO), as compare to the Upstream. The values of the heavy metals like Pb (3.845 mg/l), Cr (0.612 mg/l) Ni (0.104 mg/l) and Cu (0.128 mg/l), at Downstream point, were above Pb (3.0605 mg/l), Cr (0.0 mg/l), Ni (0.017 mg/l) and Cu (0.102 mg/l) of the Upstream point,before the Dredging points I and II, that have correlative matrix of(Pb>Fe>Mn>Zn>Cu>Ni>Cr) and Pb>Fe>Cr>Mn>Zn>Cu>Ni Downstream point. Is discovered the Downstream water is slightly acidic, high in Turbidity and TSS, but low in TDS, EC, NO3 and DO, as against the WHO drinking-water quality, due the effect of dredging on the water quality of the Ekole Creek. It is inferred that the dredging activities have negative effects on the water quality, which can be hazardous to the health of downstream user, and distort the ecosystem; therefore the commercial dredging activities should be checked in Ekole creek.

Investigating the Influence of Column Depth on the Treatment of Textile Wastewater Using Natural Zeolite

Textile industry production processes generate one of the most highly polluted wastewaters in the world. Unfortunately, the field is also challenged by the availability of relatively cheap and highly effective technologies for wastewater purification. The application of natural zeolite as a depth filter offers an alternative and potential approach for textile wastewater treatment. The performance of a depth filter treatment system can be deeply affected by the column depth and the characteristics of the wastewater to be treated. Regrettably, the information on the potential of these filter materials for the purification of textile wastewater is still scarce. Therefore, this study investigated the potential applicability of natural zeolite in terms of column depth for the treatment of textile wastewater. From the analysis results, it was observed that the filtration efficiencies were relatively low (6.1 to 13.7%) for some parameters such as total dissolved solids, electrical conductivity, chemical oxygen demand, and sodium chloride when the wastewater samples were subjected to the 0.5 m column depth. Relatively high efficiency of 82 and 93.8% was observed from color and total suspended solids, respectively, when the wastewater samples were subjected to the 0.5 m column depth. Generally, the 0.75 m column depth achieved removal efficiencies ranging from 52.3% to 97.5%, whereas the 1 m column depth achieved removal efficiencies ranging from 86.9% to 99.4%. The highest removal efficiency was achieved with a combination of total suspended solids and 1 m column depth (99.4%). In summary, the treatment approach was observed to be highly effective for the removal of total suspended solids, with a 93.8% removal efficiency when the wastewater was subjected to the 0.5 m column depth, 97.5% for 0.75 m column depth, and 99.4% for 1 m column depth. Moreover, up to 218.233 mg of color per g of the filter material was captured. The results derived in this study provide useful information towards the potential applicability of natural zeolite in the textile wastewater treatment field.

Investigation on Suitable Spat Collectiors and Culture Sites for Edible Oyster in the Coast of Bay of Bengal, Bangladesh

Potential spat collectors and suitable culture sites were investigated for the development of edible oyster culture from June to December 2019 at three study sites (Moheshkhali, the Jeti of Nuniarchora, and Sonadia) of Cox’s Bazar coast of Bangladesh. Four types of collectors such as oyster shell, earthen pot, kortal (windowpane oyster shell) and tiles were investigated. On site sampling of water quality parameters and number of spats on each collector were done at 15-days interval following standard methods. Results indicated insignificant difference (P > 0.05) in temperature, salinity, dissolved oxygen and pH, while significant difference (P < 0.05) in total dissolved solids, total suspended solids and Chl-a content of the water among the study locations. However, these parameters were in suitable range for growth and spawning of oyster. Results also indicated spat recruitment was significantly influenced by the types of collectors and study locations with significantly (P < 0.05) higher spat were recruited in Tiles. Tiles were also found to facilitate with an advantage of recycling of this collector. The location in interaction with polluting materials such as total dissolved solids and total suspended solids had a significant effect on spat recruitment rate and therefore, Sonadia was the most suitable location for spat recruitment. This study site can also be used as a suitable location for the development of oyster culture in the cost of Bay of Bengal, Bangladesh based on its environmental characteristics. Bangladesh J. Zool. 49 (2): 257-265, 2021

Evaluative Study of River Birim in Denkyembuor, Ghana, Using Water Quality Indices

Aim: To evaluate water quality of the river Birim after a two-year ban as a result of illegal mining activities in the catchment areas of the river. Methodology: Samples were taken during wet and dry seasons in acid-washed plastic containers. Two water quality indices were adapted for the river under study and used in the evaluation. These were Water Quality Index (WQI) and Heavy Metal Pollution Index (HPI). Twelve physicochemical parameters, such as pH, turbidity, conductivity, total suspended solids, total dissolved solids, total hardness, alkalinity, sulphate, phosphate, nitrate, Fluoride, and chloride which were life-threatening and generally acceptable in water quality were used to evaluate the water quality index. The computed WQI was 439.168, which fell within the unfit for drinking category with turbidity and total suspended solids positively influencing the index. Iron, (Fe), As, Mn, and Hg were used to evaluate HPI, with an index value of 39.49, which was excellent considering a critical value of 100 set, below which the water is fit for good drinking water. Conclusion: Except for heavy metal pollution, the river Birim is unfit for drinking without chemical treatment and that, the two-year ban on artisanal small-scale mining was not enough for the river to recover fully from previous pollution episodes and hence did not have any impact on water quality of the river Birim.

Application of Compact Piping Sedimentation Unit as Pretreatment for Ultrafiltration Plant

The study aimed to create a compact pretreatment unit before the ultrafiltration modules. This unit targeted to improve the inlet water quality to meet the average values of the feed water quality required for the ultrafiltration plants according to the manufacturer. The used unit in this study was a pipe worked as a sedimentation unit with inclined plates to apply the plate settler technology. The suitability of using this unit was determined by using varied water sources with different Total Suspended Solids (TSS) concentrations and different retention times. The removal efficiencies for the low TSS water source reached 96.47 %, 82.94 %, 64.80 % & 30.59 % with retention time 30 minutes, 15 minutes, 5 minutes & 20 seconds respectively. For the medium TSS water source at the same retention times, the removal efficiencies reached 97.33 %, 92.87 %, 86.10 % & 63.89 %. For the high TSS water source, the removal efficiencies reached 98.64 %, 93.86 %, 87.51 % & 76.23 %. These results make the sedimentation unit able to work as an effective pretreatment unit for the ultrafiltration units for all water sources.

The Impact of Precipitation Characteristics on the Washout of Pollutants Based on the Example of an Urban Catchment in Kielce

This paper reports the results of studies on the concentrations of total suspended solids (TSS) and heavy metals (HMs) (Cu, Zn, Cr, Ni, Cd, Pb) in stormwater. Pollutant loads were calculated for the observed high water stages. Pollutographs showing M/Mc = f(V/Vc) relationships were generated. In the description of the relationships, two functions, namely the exponential and the power functions, were employed. These represented the dynamics of the pollutant washout from the surface of the catchment area. The analyses demonstrated that the exponential function provides a slightly better description of the course of the process compared with the power function. In the former case, correlation coefficients (R) ranged from 0.900 to 0.999, whereas in the latter they ranged from 0.864 to 0.999. The analyses of correlations between the characteristics describing discharge hydrographs and the values of pollutant washout coefficients indicate that the strongest statistical relationships were identified for TSS. It was demonstrated that the value of the washout coefficient for total suspended solids (kTSS) drops with an increase in rain intensity (q). This also depends on the 10-min precipitation (Ptd=10). Regarding the studied heavy metals, a statistically significant impact of the dry period (tbd) on the washout coefficient was observed only for lead (kPb). Taking into account the washout coefficient in the first flush model makes it possible to improve the accuracy of calculations. This is important for understanding the studied phenomenon.