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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">medlit</journal-id><journal-title-group><journal-title xml:lang="ru">Гигиена и санитария</journal-title><trans-title-group xml:lang="en"><trans-title>Hygiene and Sanitation</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">0016-9900</issn><issn pub-type="epub">2412-0650</issn><publisher><publisher-name>Federal Scientific Center of Hygiene named after F.F. Erisman</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.47470/0016-9900-2024-103-5-489-495</article-id><article-id custom-type="edn" pub-id-type="custom">mgyfla</article-id><article-id custom-type="elpub" pub-id-type="custom">medlit-4054</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>МЕТОДЫ ГИГИЕНИЧЕСКИХ ИССЛЕДОВАНИЙ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>METHODS OF HYGIENIC AND EXPERIMENTAL INVESTIGATIONS</subject></subj-group></article-categories><title-group><article-title>Экспресс-определение хлорорганических пестицидов в воде методом экстракционного вымораживания в комбинации с газовой хроматографией</article-title><trans-title-group xml:lang="en"><trans-title>Express-determination of organochlorine pesticides in water by method of extractive freezing-out in combination with gas chromatography</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-5816-9624</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Бехтерев</surname><given-names>Виктор Николаевич</given-names></name><name name-style="western" xml:lang="en"><surname>Bekhterev</surname><given-names>Viktor N.</given-names></name></name-alternatives><email xlink:type="simple">vic-bekhterev@yandex.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Мищенко</surname><given-names>Ирина Витальевна</given-names></name><name name-style="western" xml:lang="en"><surname>Mishchenko</surname><given-names>Irina V.</given-names></name></name-alternatives><email xlink:type="simple">sochi_fguz_lab@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Комарова</surname><given-names>Наталья Сергеевна</given-names></name><name name-style="western" xml:lang="en"><surname>Komarova</surname><given-names>Natalia S.</given-names></name></name-alternatives><email xlink:type="simple">sochi_fguz_lab@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Сочинский филиал ФБУЗ «Центр гигиены и эпидемиологии в Краснодарском крае»</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Sochi Branch of the Center for Hygiene and Epidemiology in the Krasnodar Territory</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2024</year></pub-date><pub-date pub-type="epub"><day>17</day><month>06</month><year>2024</year></pub-date><volume>103</volume><issue>5</issue><fpage>489</fpage><lpage>495</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Бехтерев В.Н., Мищенко И.В., Комарова Н.С., 2024</copyright-statement><copyright-year>2024</copyright-year><copyright-holder xml:lang="ru">Бехтерев В.Н., Мищенко И.В., Комарова Н.С.</copyright-holder><copyright-holder xml:lang="en">Bekhterev V.N., Mishchenko I.V., Komarova N.S.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.rjhas.ru/jour/article/view/4054">https://www.rjhas.ru/jour/article/view/4054</self-uri><abstract><sec><title>Введение</title><p>Введение. Контролю чистоты водных ресурсов уделяется особое внимание. Загрязнение водной среды хлорорганическими пестицидами (ХОП), их метаболитами до сих пор остаётся серьёзной проблемой. Определение токсикантов в воде, особенно загрязнённой бытовыми, промышленными стоками, осложнено необходимостью дополнительной предварительной подготовки пробы к этапу физико-химического исследования.</p><p>Цель исследования – разработка быстрого метода определения ХОП с использованием инновационной технологии выделения органических соединений.</p></sec><sec><title>Материалы и методы</title><p>Материалы и методы. Объекты экспериментального изучения – модельные водные растворы ДДТ, ДДД, ДДЭ, ГХБ и изомеров ГХЦГ и реальные объекты. Определение токсикантов в питьевой, морской и канализационной бытовой воде вели методом экстракционного вымораживания (ЭВ) в этоксиэтан в комбинации с газовой хроматографией.</p></sec><sec><title>Результаты</title><p>Результаты. Изучена и подтверждена эффективность извлечения ХОП методом ЭВ из воды на этапе подготовки пробы к газохроматографическому исследованию. Получены результаты, подтверждающие точность и низкую погрешность определения токсикантов.</p></sec><sec><title>Ограничения исследования</title><p>Ограничения исследования. Диапазон рН исследованных водных смесей составлял от 3,0 до 7,0. Предварительно установлено, что в щелочной среде происходит снижение концентрации ряда аналитов во времени, что требует дополнительного изучения.</p></sec><sec><title>Заключение</title><p>Заключение. Создана методика с предварительным выделением аналитов экстракционным вымораживанием для последующего газохроматографического определения. Областью применения разработки является санитарно-гигиенический контроль качества воды. Метод обеспечивает определение ХОП в объёме пробы 10 мл на уровне ниже установленных ПДК с относительной погрешностью, не превышающей 20%. Пробоподготовка осуществляется в одну стадию при отрицательных температурах, что благоприятно для улучшения условий труда и техники безопасности, поскольку значительно уменьшается летучесть растворителей и компонентов исследуемого образца. Процедура проста, не предполагает дополнительных требований к квалификации оператора, обладает низкой стоимостью, расходом реактивов, материалов. Продолжительность этапа подготовки пробы не превышает 30 мин.</p><p>Соблюдение этических стандартов. Исследование не требует заключения комитета по биомедицинской этике и иных документов.</p></sec><sec><title>Участие авторов</title><p>Участие авторов: Бехтерев В.Н. – концепция и дизайн исследования, планирование и проведение экспериментальных исследований, статистическая обработка массива результатов, анализ данных литературы, обсуждение результатов, написание и утверждение окончательного варианта текста статьи; Мищенко И.В. – обсуждение результатов, редактирование, утверждение окончательного варианта текста; Комарова Н.С. – утверждение окончательного варианта статьи, ответственность за целостность всех частей статьи.</p></sec><sec><title>Конфликт интересов</title><p>Конфликт интересов. Авторы декларируют отсутствие явных и потенциальных конфликтов интересов в связи с публикацией данной статьи.</p></sec><sec><title>Финансирование</title><p>Финансирование. Исследование не имело спонсорской поддержки.</p></sec><sec><title>Поступила</title><p>Поступила: 18.03.2024 / Принята к печати: 09.04.2024 / Опубликована: 17.06.2024</p></sec></abstract><trans-abstract xml:lang="en"><sec><title>Introduction</title><p>Introduction. Special attention is paid to the control of the purity of water resources. Pollution by the aquatic medium with organochlorine pesticides (OChPs) and their metabolites still remains a serious problem. The determination of toxicants in water, and even more so, contaminated with household and industrial wastewater, is complicated by the need for additional preliminary sample preparation for the stage of physical-chemical research. </p><p>The purpose of the research is to develop a rapid method for determining OChPs using innovative technology for the isolation of organic compounds.</p></sec><sec><title>Materials and methods</title><p>Materials and methods. The objects of experimental study were model aqueous solutions of dichlorodiphenyltrichloretan (DDT), dichlorodiphenyldihloromethylmethane (DDD), dichlorodiphenyldihlorethylene (DDE), hexachlorobenzene (HCB), and hexachlorocyclohexane (HCCH) isomers and real objects. The determination of toxicants in drinking, marine, and sewage household water was carried out by extractive freezing-out (EF) into ethoxyethane in combination with gas chromatography.</p></sec><sec><title>Results</title><p>Results. The efficiency of extraction of OChPs by the EF method from water at the stage of sample preparation for gas chromatographic examination has been studied and confirmed. The results confirming the accuracy and low error in the determination of toxicants were obtained.</p></sec><sec><title>Limitations</title><p>Limitations. The pH range of the studied aqueous mixtures was from 3 to 7. It was previously established that in an alkaline medium there is a noticeable concentration decrease of some analytes over time, which requires additional study.</p></sec><sec><title>Conclusion</title><p>Conclusion. A technique of the preliminary isolation of analytes by extractive freezing-out with subsequent gas chromatographic determination has been developed. The application field of the development is sanitary and hygienic control of the water quality. The method provides the determination of OChPs in a sample volume of 10 ml at a level below the established MPC with a relative error not exceeding 20%. Sample preparation is carried out in one step without any additional manipulations with the sample at subzero temperatures, which is favourable for improving working conditions and safety, since the volatility of solvents and components of the test sample is significantly reduced. The procedure is simple, there are no additional requirements for the qualification of a operator. It has a low cost, consumption of reagents and materials. The duration of the sample preparation stage does not exceed 30 minutes.</p><p>Compliance with ethical standards. The study does not require the conclusion of the biomedical ethics committee and other documents.</p></sec><sec><title>Contribution</title><p>Contribution: Bekhterev V.N. – concept and design of the study, planning and implementation of experimental studies, statistical processing of the array of results, analysis of literary data, discussion of the results and writing the manuscript of the article, approval of the final version of the text; Mishchenko I.V. – discussion of the results, editing, approval of the final version of the text; Komarova N.S. – approval of the final version of the manuscript of the article, responsibility for the integrity of all parts of the article.</p></sec><sec><title>Conflict of interest</title><p>Conflict of interest. The authors declare no conflict of interest.</p></sec><sec><title>Acknowledgement</title><p>Acknowledgement. The study had no sponsorship.</p></sec><sec><title>Received</title><p>Received: March 18, 2024 / Accepted: April 9, 2024 / Published: June 17, 2024</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>вода</kwd><kwd>питьевая</kwd><kwd>морская</kwd><kwd>сточная</kwd><kwd>контроль</kwd><kwd>ДДТ</kwd><kwd>ДДД</kwd><kwd>ДДЭ</kwd><kwd>ГХБ</kwd><kwd>изомеры ГХЦГ</kwd><kwd>экстракционное вымораживание</kwd><kwd>криоэкстрактор</kwd><kwd>хроматография</kwd></kwd-group><kwd-group xml:lang="en"><kwd>water</kwd><kwd>drinking water</kwd><kwd>marine</kwd><kwd>wastewater</kwd><kwd>control</kwd><kwd>DDT</kwd><kwd>DDD</kwd><kwd>DDE</kwd><kwd>HCB</kwd><kwd>HCCH isomers</kwd><kwd>extractive freezing-out</kwd><kwd>cryoextractor</kwd><kwd>chromatography</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Кузьмин С.В., Добрева Н.И., Федорова Н.Е. 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