{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T00:54:57Z","timestamp":1791248097440,"version":"4.1.0"},"reference-count":22,"publisher":"American Society of Parasitologists","issue":"4","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Journal of Parasitology"],"published-print":{"date-parts":[[2024,7,18]]},"abstract":"<jats:p>Some helminth test methods for sanitation samples include a phase extraction step to reduce lipid content and final pellet size before microscopy. Hydrophilic and lipophilic solutions are used to create 2 phases, with a plug of organic material or debris in between, whilst eggs are supposedly compacted at the bottom of the test tube. We tested 10% formalin, acetoacetic buffer, and acid alcohol as the hydrophilic solutions, and ethyl acetate and diethyl ether as the lipophilic solvents for egg recoverability from water, primary sludge, and fatty sludge. Normally, the supernatant and debris plug are discarded and the sedimented pellet of eggs is microscopically examined. We, however, also collected the entire supernatant plus debris plug to determine where eggs were possibly lost. We found that eggs were lost when samples were extracted with 10% formalin + ethyl acetate, 10% formalin + diethyl ether, acetoacetic buffer + ethyl acetate, and acetoacetic buffer + diethyl ether combinations (&lt;50% egg recovery). Acid alcohol + ethyl acetate resulted in 93.2, 89.8, and 57.3% egg recovery in the pellet of water, primary sludge, and fatty sludge, respectively; however, the size of the final pellet was not reduced, defeating the purpose of the extraction step. We thus recommend that this step be excluded.<\/jats:p>","DOI":"10.1645\/22-57","type":"journal-article","created":{"date-parts":[[2024,7,17]],"date-time":"2024-07-17T04:23:04Z","timestamp":1721190184000},"page":"295-299","source":"Crossref","is-referenced-by-count":3,"title":["Ascaris suum Egg Recovery from Sludge Samples After Phase Extraction"],"prefix":"10.1645","volume":"110","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7834-3850","authenticated-orcid":false,"given":"D.","family":"Naidoo","sequence":"first","affiliation":[{"name":"Water, Sanitation and Hygiene Research and Development Centre, Howard College Campus, University of KwaZulu-Natal, Durban 4041, South Africa."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"C. E.","family":"Archer","sequence":"additional","affiliation":[{"name":"Water, Sanitation and Hygiene Research and Development Centre, Howard College Campus, University of KwaZulu-Natal, Durban 4041, South Africa."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1220","reference":[{"key":"2","doi-asserted-by":"crossref","unstructured":"I. D. Amoah, G. Singh, T. A. Stenstr\u00f6m, et al.  \"Acta Tropica.\"  169, \"Detection and quantification of soil-transmitted helminths in environmental samples: A review of current state-of-the-art and future perspectives.\" 187 (2017)","DOI":"10.1016\/j.actatropica.2017.02.014"},{"key":"11","unstructured":"\"R: a Language and Environment for Statistical Computing.\"  (2018)"},{"key":"1","doi-asserted-by":"crossref","unstructured":"A. V. Allen  and D. S. Ridley  \"Journal of Clinical Pathology.\"  23, \"Further observations on the formol\u2013ether concentration technique for faecal parasites.\" 545 (1970)","DOI":"10.1136\/jcp.23.6.545"},{"key":"3","unstructured":"R. M. Ayres  and D. D. Mara  \"Analysis of Wastewater for Use in Agriculture: A Laboratory Manual of Parasitological and Bacteriological Techniques.\"  35 (1996)"},{"key":"4","unstructured":"M. Cheeseborough,  \"Medical Laboratory Manual for Tropical Countries.\"  1, 519 (1981)"},{"key":"5","doi-asserted-by":"crossref","unstructured":"P. A. Collender, A. E. Kirby, D. G. Addiss, et al.  \"Trends in Parasitology.\"  31, \"Methods for quantification of soil-transmitted helminths in environmental media: Current techniques and recent advances.\" 625 (2015)","DOI":"10.1016\/j.pt.2015.08.007"},{"key":"7","doi-asserted-by":"crossref","unstructured":"P. G. Gaspard, J. Wiart, J. Schwartzbrod,  \"Bioresource Technology.\"  52, \"Urban sludge reuse in agriculture: Waste treatment and parasitological risk.\" 37 (1995)","DOI":"10.1016\/0960-8524(94)00149-U"},{"key":"8","doi-asserted-by":"publisher","unstructured":"M. M. Manser, A. C. S. Saez, P. L. Chiodini,  \"PloS Neglected Tropical Diseases.\"  10, \"Faecal parasitology: Concentration methodology needs to be better standardised.\" e0004579 (2016)","DOI":"10.1371\/journal.pntd.0004579"},{"key":"9","doi-asserted-by":"crossref","unstructured":"K. L. Nelson  and J. L. Darby  \"Applied Environmental Microbiology.\"  7, \"Inactivation of viable Ascaris eggs by reagents during enumeration.\" 5453 (2001)","DOI":"10.1128\/AEM.67.12.5453-5459.2001"},{"key":"10","doi-asserted-by":"crossref","unstructured":"K. Pakdad, S. D. Nasab, F. A. 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Melvin, et al.  \"Journal of Clinical Microbiology.\"  10, \"Ethyl acetate as a substitute for diethyl ether in the formalin\u2013ether sedimentation technique.\" 852 (1979)","DOI":"10.1128\/jcm.10.6.852-853.1979"},{"key":"6","doi-asserted-by":"crossref","unstructured":"E. D. David  and W. D. Lindquist  \"Journal of Parasitology.\"  68, \"Determination of the specific gravity of certain helminth eggs using sucrose density gradient centrifugation.\" 916 (1982)","DOI":"10.2307\/3281005"}],"container-title":["Journal of Parasitology"],"original-title":[],"deposited":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T00:25:57Z","timestamp":1791246357000},"score":1,"resource":{"primary":{"URL":"https:\/\/bioone.org\/journals\/journal-of-parasitology\/volume-110\/issue-4\/22-57\/Ascaris-suum-Egg-Recovery-from-Sludge-Samples-After-Phase-Extraction\/10.1645\/22-57.full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,7,18]]},"references-count":22,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2024,8,1]]}},"URL":"https:\/\/doi.org\/10.1645\/22-57","relation":{},"ISSN":["0022-3395","1937-2345"],"issn-type":[{"value":"0022-3395","type":"print"},{"value":"1937-2345","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,7,18]]}}}