The impact of traditional coffee processing on river water quality in Ethiopia and the urgency of adopting sound environmental practices

Although waste from coffee processing is a valuable resource to make biogas, compost, and nutrient-rich animal food, it is usually dumped into nearby water courses. We carried out water quality assessment at 44 sampling sites along 18 rivers that receive untreated waste from 23 coffee pulping and processing plants in Jimma Zone, Ethiopia. Twenty upstream sampling sites free from coffee waste impact served as control, and 24 downstream sampling sites affected by coffee waste were selected for comparison. Physicochemical and biological results revealed a significant river water quality deterioration as a result of disposing untreated coffee waste into running water courses. During coffee-processing (wet) season, the highest organic load (1,900?mg/l), measured as biochemical oxygen demand, depleted dissolved oxygen (DO) to a level less than 0.01?mg/l, and thus curtailed nitrification. During off season, oxygen started to recuperate and augmented nitrification. The shift from significantly elevated organic load and reduced DO in the wet season to increased nitrate in the off season was found to be the determining factor for the difference in macroinvertebrate community structure as verified by ordination analysis. Macroinvertebrate diversity was significantly reduced in impacted sites during the wet season contrary to the off season. However, there was a significant difference in the ratio of sensitive to pollution-tolerant taxa in the off season, which remained depreciated in the longer term. This study highlights the urgency of research exploring on the feasibility of adopting appropriate pollution abatement technologies to implement ecologically sound coffee-processing systems in coffee-growing regions of Ethiopia.     

Occurrence of selected pharmaceuticals in river water in Japan and assessment of their environmental risk

The existence of pharmaceuticals in the water environment is thought to be a potential problem for aquatic organisms. In this study, we conducted a nationwide survey to clarify the occurrence of 24 selected pharmaceuticals in major Japanese rivers and evaluated their environmental risk to aquatic organisms. We found a total of 22 substances in river waters at concentrations from several nanograms per liter to several micrograms per liter. We found the highest, which was 2.4 μg/L of caffeine, followed by 1.5 μg/L of crotamiton and 1.4 μg/L of sulpiride. We conducted an environmental risk assessment of the 22 pharmaceuticals detected in river water, for which predicted no-effect concentration (PNEC) values for crustacea and algae had been obtained. The measured environmental concentration/PNEC values of four substances, caffeine, carbamazepine, clarithromycin, and ketoprofen, exceeded 0.1 with the maximum value of 9.0 for clarithromycin. As clarithromycin exhibits a high environmental risk to aquatic organisms, particular attention is required.     

Use of water quality index and multivariate statistical techniques for the assessment of spatial variations in water quality of a small river

Rapid urban development has led to a critical negative impact on water bodies flowing in and around urban areas. In the present study, 25 physiochemical and biological parameters have been studied on water samples collected from the entire section of a small river originating and ending within an urban area. This study envisaged to assess the water quality status of river body and explore probable sources of pollution in the river. Weighted arithmetic water quality index (WQI) was employed to evaluate the water quality status of the river. Multivariate statistical techniques namely cluster analysis (CA) and principal component analysis (PCA) were applied to differentiate the sources of variation in water quality and to determine the cause of pollution in the river. WQI values indicated high pollution levels in the studied water body, rendering it unsuitable for any practical purpose. Cluster analysis results showed that the river samples can be divided into four groups. Use of PCA identified four important factors describing the types of pollution in the river, namely (1) mineral and nutrient pollution, (2) heavy metal pollution, (3) organic pollution, and (4) fecal contamination. The deteriorating water quality of the river was demonstrated to originate from wide sources of anthropogenic activities, especially municipal sewage discharge from unplanned housing areas, wastewater discharge from small industrial units, livestock activities, and indiscriminate dumping of solid wastes in the river. Thus, the present study effectively demonstrates the use of WQI and multivariate statistical techniques for gaining simpler and meaningful information about the water quality of a lotic water body as well as to identify of the pollution sources.     

建设项目环评报告书中存在的水环境监测问题及解决方法

项目建设前的环境质量(包括水环境质量)是环境影响评价的基础,预测项目建设后的环境质量是环境可行性评价结论的依据,环境质量的表征数据是通过环境监测工作取得,环境监测的规范性要求,开展监测要得到的数据必须具备"五性",才能表征某一监测地区的环境质量。由于环境评价的中介服务性,以及时间与经费的关系,对环境监测点位、频次进行压缩与省略,使得监测数据无法保障其代表性,影响建设项目环境影响报告书得出可信的结论。如何保障监测数据的质量,以最少的监测点、最恰当的监测时期、最少的监测频次,取得最有代表性的数据表征建设项目周围的环境质量,从而确保评价依靠的环境质量基础可靠,评价结论可信,是一个值得探讨的问题。     

Simultaneous determination of 2-phenylbenzotriazole-type mutagens, PBTA-1 through -8, in river water by liquid chromatography-tandem mass spectrometry

We describe a method for the simultaneous determination of eight kinds of phenylbenzotriazole-type mutagens (PBTA-1, -2, -3, -4, -5, -6, -7 and -8) in river water based on liquid chromatography-tandem mass spectrometry (LC/MS/MS). The application of dopant-assisted atmospheric pressure photoionization (APPI) for the detection of the PBTAs was studied. The APPI technique provided higher PBTA signal intensities than those obtained with an electrospray ionization (ESI) source, and the APPI method was used for the determination of the PBTAs. A solid-phase extraction procedure was used for the extractions of PBTA-1 through -8 from river water. The procedure was rapid and the relative standard deviations were below 15%. The detection limits of PBTA-1 through -8 in river water using the proposed method were found to range from 0.04 to 0.5 ng L(-1) and PBTAs were successfully detected in river water at sub-ng L(-1) levels.     

Monitoring the impact of urban effluents on mineral contents of water and sediments of four sites of the river Ravi, Lahore

We assessed the impact of urban effluents on the concentrations of selected minerals (Cd, Cr, Cu, Fe, Pb, Zn, Mn, Ni, and Hg) in river Ravi before and after its passage through Lahore city. Water and sediment samples were collected from three lowly to highly polluted downstream sites (Shahdera (B), Sunder (C), and Balloki (D)) alongside the least polluted upstream site (Siphon (A)) during high and low river flow seasons. All the mineral concentrations increased up to site C but stabilized at site D, showing some recovery as compared to the third sampling site. The trend of mean mineral concentration was significantly higher during the low than the high flow season at all the sites. The mean Hg concentrations approached 0.14 and 0.12 mg/l at site A which increased (%) up to 107 and 25 % at site B, 1,700 and 1,317 % at site C, and 1,185 and 1,177 % at site D during low and high river flows, respectively. All mineral concentrations were much higher in the sediment than the water samples. Mean Cd (917 %), Cr (461 %), Cu (300 %), Fe (254 %), Pb (179 %), Zn (170 %), Mn (723 %), Ni (853 %), and Hg (1,699 %) concentrations were higher in riverbed sediments sampled from site C in comparison with the sample collected at site A during low flow season. The domestic and industrial discharges from Lahore city have created undesirable water qualities during the low river flow season. As majority of the mineral levels in the river Ravi were higher than the permissible and safe levels, this is of immediate concern for riverine fish consumers and the users of water for recreation and even irrigation. The use of these waters may pose health risks, and therefore, urgent intervention strategies are needed to minimize river water pollution and its impact on fish-consuming communities of this study area and beyond.     

Assessment and occurrence of various heavy metals in surface water of Ganga river around Kolkata: a study for toxicity and ecological impact

A study was conducted during November, 2005–October, 2006 to evaluate the surface water quality of river Ganga around Kolkata. The samples were analyzed for a number of physico-chemical parameters using standard laboratory procedures and giving prime thrust to determine the heavy metal concentrations (Fe, Mn, Cu, Zn, Pb, Cd, Cr, and Ni) of surface water at four different locations of the river Ganga around Kolkata from two points (middle of the river stream and a discharge point) at each location. Out of 96 samples analyzed, Fe, Mn, Cu, Zn, and Ni were detected in 71, 47, 38, 60, and 45 samples in the concentrations ranging from 0.013 to 5.49, 0.022 to 1.78, 0.003 to 0.033, 0.005 to 0.293, and 0.045 to 0.24 mg L^???1, respectively. Cd and Pb were detected in six and 21 samples in the range of 0.005 to 0.006 and 0.05 to 0.53 mg L^???1, respectively. But Cr was not detected in any of the samples analyzed. The metals exhibited no significant variation with respect to sampling locations as well as discharge points. However, the concentration of those metals varied with season, being higher in rainy and lower in winter season.