{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T02:45:26Z","timestamp":1775011526101,"version":"3.50.1"},"reference-count":38,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T00:00:00Z","timestamp":1770768000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005632","name":"National Centre for Research and Development","doi-asserted-by":"crossref","award":["BIOSTRATEG3\/347105\/9\/NCBR\/2017"],"award-info":[{"award-number":["BIOSTRATEG3\/347105\/9\/NCBR\/2017"]}],"id":[{"id":"10.13039\/501100005632","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Monitoring soil contamination from petroleum products is vital for protecting human health and the environment. In forestry, hydraulic oil spills frequently result from leaks in equipment such as harvesters. This study evaluates a custom-built, inexpensive electronic nose, equipped with a Figaro TGS gas sensor array, for discriminating between pristine and contaminated soil samples. Two oil types and three pollution intensities were analyzed. The constructed electronic nose applied two sensor operation modes: (i) response to change of sensor operation condition from clean air to target odors and (ii) response to sensor heater temperature modulation. Classification was performed using Random Forest and Support Vector Machine (SVM) algorithms, and Linear Discriminant Analysis (LDA) was used to explore multidimensional data patterns. The sensor heater temperature modulation mode provided superior classification performance. Measurements at room temperature achieved an accuracy of 97%, clearly outperforming measurements on samples heated to 60 \u00b0C (75%). While the system successfully identified biodegradable oil contamination, standard mineral oil was more challenging to detect. Among the sensors tested, TGS 2602 was the most effective. These findings indicate that portable electronic noses can provide a statistically robust and cost-effective tool for assessing the severity of soil pollution.<\/jats:p>","DOI":"10.3390\/s26041154","type":"journal-article","created":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T09:15:12Z","timestamp":1770801312000},"page":"1154","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Detection of Hydraulic Oil-Polluted Soil Using a Low-Cost Electronic Nose with Sample Heating"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2906-246X","authenticated-orcid":false,"given":"Piotr","family":"Borowik","sequence":"first","affiliation":[{"name":"Institute of Theory of Electrical Engineering, Measurement and Information Systems, Faculty of Electrical Engineering, Warsaw University of Technology, ul. Koszykowa 75, 00-662 Warszawa, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Przemys\u0142aw","family":"Pluta","sequence":"additional","affiliation":[{"name":"Forestry Students\u2019 Scientific Association, Forest Department, Warsaw University of Life Sciences, Nowoursynowska 166, 02-787 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9666-8483","authenticated-orcid":false,"given":"Rafa\u0142","family":"Tarakowski","sequence":"additional","affiliation":[{"name":"Faculty of Physics, Warsaw University of Technology, ul. Koszykowa 75, 00-662 Warszawa, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4688-2582","authenticated-orcid":false,"given":"Tomasz","family":"Oszako","sequence":"additional","affiliation":[{"name":"Forest Protection Department, Forest Research Institute, ul. Braci Le\u015bnej 3, 05-090 S\u0119kocin Stary, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"135492","DOI":"10.1016\/j.snb.2024.135492","article-title":"Soil pesticides pollution detection and specific recognition using electronic nose","volume":"408","author":"Kong","year":"2024","journal-title":"Sens. Actuators B Chem."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Kong, C., Sun, L., Li, X., Yan, Y., Chang, Z., Li, M., Gou, F., and Rong, B. (2025). Rapid and Simultaneous Detection of Petroleum Hydrocarbons and Organic Pesticides in Soil Based on Electronic Nose. Sensors, 25.","DOI":"10.3390\/s25020380"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Wen, X., Liu, R., Cai, Q., Bu, F., and Wan, M. (2012). Simulated Detection of VCHs in Soil by Using a Self-made Electronic Nose. 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