DOI: 10.5061/dryad.rbnzs7hg4
title: Data from: Study of helminth eggs (Ascaris suum) inactivation by anaerobic digestion and electrochemical treatment

description: The use of insufficiently treated wastewater or fecal sludge in
 agriculture raises concerns because of the pathogen content. Helminth eggs
 are one of the most crucial pathogens for ensuring public health and
 safety. Widely used disinfection treatment methods do not guarantee the
 complete inactivation of helminth eggs. The current study evaluated the
 effectiveness of anaerobic digestion and electrochemical process for
 helminth (Ascaris suum) egg inactivation. Lab-scale biochemical methane
 potential (BMP) assay was conducted by spiking A. suum eggs in a serum
 bottle. Total solid (TS), volatile solid (VS), pH, biogas production and
 its composition, and volatile fatty acids (VFA) were analyzed along with
 A. suum inactivation, every 3rd day for the initial 15 days and 5th day
 till 45 days. The results documented 98% inactivation of A. suum eggs
 (0.15 eggs/ml) in 35 days and remained at 0.14 eggs/ml till the 45th day.
 Correlation analysis revealed positive relation of non-viable eggs with pH
 and a negative relationship with all the other parameters. In the second
 set of experiments, a hypochlorite (4700ppm) solution was generated by
 electrolysis of aqueous NaCl solution in a membrane-less electrochemical
 cell. The hypochlorite was diluted (940, 470, 235, and 156ppm) in
 wastewater, spiked with A. suum eggs and then examined for
 inactivation at regular intervals. 10% inactivation was achieved at 940ppm
 concentration in 24h. This study revealed that the inactivation of A. suum
 eggs by anaerobic digestion or electrochemical treatment is a combined
 effect of more than one parameter.
description: The manuscript contains
 comprehensive information on data collecting, and the README.txt file
 contains detailed descriptions of each data file, which are briefly
 outlined here: <strong>1.
 METHODS</strong> <strong>Anaerobic
 Digestion- BMP (Biochemical Methane Potential)
 Assay</strong> <strong>1.1 Experimental setup
 </strong> The BMP assay was performed in serum bottles for
 the co-digestion of faecal sludge and food waste. Each bottle was
 subjected to a loading rate of biomass of 1.5kg
 VS/m<sup>3</sup>.
 Macro and micronutrients, Na-bicarbonate, digested from an anaerobic pilot
 reactor was used as inoculum, and the final volume was raised to 100ml by
 adding distilled water. <em>A. suum</em> eggs were procured
 from Excelsior Sentinel, USA, a mixture of viable and non-viable eggs, and
 spiked into the bottles. The experiment was performed using
 two bottles in each set; one bottle from each set was taken out at each
 sampling point for analysis, and another bottle along with the remaining
 bottles from the set was used to take the gas reading every day. The setup
 was maintained at room temperature (28 ± 2°C). 
 <strong>1.2 Parameter analysis
 </strong> The different experimental parameters (pH, TS,
 VS, CH<sub>4</sub>,
 CO<sub>2</sub>, H<sub>2</sub>S, VFA and Helminth
 eggs) analyzed along with the method used are given in
 Table 1. Biogas
 production was estimated daily by measuring the gas volume generated using
 a water displacement unit. VFA
 analysis was conducted using the titration
 method Helminth eggs were analysed by UKZN PRG
 helminth method, which included filtration, sedimentation, and
 centrifugation. Using the ZEISS Primo Star microscope, eggs were observed
 and counted. Images were captured by using Cockpit software which comes
 with the microscope. All parameters were examined in
 duplicate every 3<sup>rd</sup> day for the first 15 days, then
 every 5<sup>th</sup> day till 45 days. 
 <strong>1.3 Statistical
 analysis </strong> All the data were checked for normality
 and homogeneity of variance. The relationship between <em>A.
 suum</em> inactivation and all the other parameters was studied
 using correlation analysis. Statistical tests were performed using SPSS
 (IMB SPSS Statistics 25) software. <strong>2. Electrochemical treatment for Helminth egg
 inactivation </strong> The laboratory-scale electrochemical cell (EC)
 was set up in a 1000 ml beaker.
 A titanium plate was used as an anode electrode. The cathode
 electrode was made of SS 304 stainless-steel mesh. To apply a consistent
 voltage, a variable DC supply unit was used. The electrochemical cell
 solution was continuously mixed with a magnetic stirrer to generate
 hypochlorite, which was then employed as a disinfectant for the
 inactivating <em>A. suum</em> eggs. 
 In this study,
 hypochlorite was generated by electrolysis of 2 % NaCl solution.
 Electrolysis was performed for 2 hours, producing 4700ppm hypochlorite.
 The generated hypochlorite was diluted in various ratios with distilled
 water. Helminth eggs were spiked into all diluted solutions, and helminth
 inactivation was observed under a microscope after 15 minutes, 30 minutes,
 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, and 24
 hours.
description: For a description of the uploaded data, files, and script, see
 README.txt. In summary, there are total twelve data
 files.  Files pH-PP and SM_CSV, Total Solids (TS) and
 Volatile Solids (VS)_PP and SM_CSV, Volatile Fatty Acids (VFA)_PP and
 SM_CSV, Biogas_PP and SM_CSV, Biogas composition (CH4, CO2 and H2S)_PP and
 SM_CSV, A. suum_PP and SM_CSV contains details of pH, TS VS, VFA, Biogas,
 Biogas composition, and Ascaris suum data respectively. File number
 seven [A.suum statistical data  file_PP and SM_CSV] contains data used for
 statistical significance and correlation analysis. File number eight [A.
 suum stat data output file_PP and SM] is output of the statistical
 significance and correlation data. File number nine and ten README.txt
 File_PP and SM and README.md contains information on methodology and
 experimental setup. File eleven and twelve Supporting figures_PP and SM
 and Supporting tables_PP and SM contain figures and tables
 respectively.