A simplified approach to monitoring the COVID-19 epidemiologic situation using waste water analysis and its application in Russia

The number of registered cases of COVID-19 is increasing in the world, and some countries are reporting a second wave of the pandemic. Accurate and real time information about epidemiological situation is therefore urgently needed for managing decisions in the countries, regions and municipalities which are affected. Massive testing of viral presence in human saliva, a smear from the nose, nasopharynx and / or oropharynx, bronchial lavage water obtained by fibrobronchoscopy (bronchoalveolar lavage), as well as from (endo) tracheal, nasopharyngeal aspirate, sputum, biopsy or autopsy material of the lungs, whole blood, serum or antibodies presence in blood cannot give relevant information about the COVID-19 infection rate in the community since simultaneous testing of the whole community is not technically possible, the information obtained in testing of specific groups is retarded and, in addition, such testing is expensive. The alternative to mass testing of the population is the testing of wastewater that could contain SARS-CoV-2 particles originating from excreta. Such testing has several limitations connected with the particularities of the testing procedure. In the present study, a modified approach for detection of COVID-19 infection rate using wastewater analysis has been developed. The approach includes i) the creation of a calibration curve on the basis of the serial dilution of excreta collected from people who are infected with COVID-19 and ii) the analysis of wastewater samples and their serial dilutions but the approach excludes usage of concentration techniques before wastewater sample analysis as well as usage of external control in RT-PCR reactions for calculation of numbers of viral particles. The minimum infection rate that can be detected using this approach is 0.01%. The approach developed was used to investigate wastewater from eleven sewage inspection chambers in the city of Kazan (Russia). It was demonstrated that the average infection rate of people using these sewers was over 0.4% in July 2020.

Preliminary Column Study and Biosorption Kinetic Profile of Cadmium (II) by Epichlorohydrin-Crosslinked Lumbang (Aleurites molucanna) Chitosan Composite

In this study, the biosorption potential of lumbang (Aleurites molucanna)-derived activated carbon towards Cd(II) in aqueous solution was investigated by coating and crosslinking the adsorbent with chitosan and epichlorohydrin, respectively. Batch adsorption studies were performed, and the effects of various parameters were evaluated. Results have shown that the optimum biosorption potential occurs at pH: 6.0, contact time: 45 min, temperature: 40°C, adsorbent dosage: 12 g/L, and initial Cd(II) concentration: 5 ppm. The biosorption kinetic profile obeyed the pseudo second-order kinetic model (R2=96.87%, p<0.001). Preliminary column study and waste water analysis revealed significant removal of Cd(II), with 89.59% and 49.08% of Cd(II) adsorbed and desorbed, respectively. There were significant reductions in the biochemical and chemical oxygen demand values of the waste water before and after passing through the column.

Lignin Degradation Through A Combined Process of Ionizing Irradiation and A Biological Treatment

In this work, the degradation of lignin was studied through a combined process of ionizing irradiation and a biological treatment. For the irradiation stage, two options were tested at the beginning: a gamma irradiation from a Cobalt source at a dose rate of 0.4 kGy/h and a beta irradiation from a linear electron accelerator at a dose rate of 827 kGy/h, in both cases for a dose of 10 kGy. Through UV-visible spectrophotometric scanning, we found better results for the lignin degradation by the beta irradiation; therefore, five higher doses: 20, 30, 40, 50 and 60 kGy were tested. Spectrophotometry, infrared spectrometry and waste water analysis allowed to determine 60 kGy as the best dose. Finally, an anaerobic biological treatment was used for the subsequent degradation of lignin. It was carried out as a batch process that lasted approximately 11 days. The combined process enhanced the BOD

Helminth eggs in wastewater: quantification technique

In the framework of agricultural wastewater reuse, the W.H.O. has defined a parasitological quality for sewage with less than one nematode egg per liter. The purpose of this work is to define an effective method to detect helminth eggs in wastewater. Seven techniques have been applied to waste water analysis, with a comparison of their respective results, varying from 26 to 74 %. Be it in the framework of artificial contamination or on site, the best results were obtained with the diphasic technique perfected at the laboratory including a treatment with antiformine at 8 % + ethylacetate followed by a flotation with zinc sulphate at 55%. The validation in the laboratory of the methods performance on treated wastewater allowed us to show that the yield of the method is significantly independent of the egg concentration as well as giving good homogeneity of results with a concentration of 1 egg/litre.