{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T17:02:08Z","timestamp":1789750928990,"version":"4.0.1"},"reference-count":56,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2010,11,17]],"date-time":"2010-11-17T00:00:00Z","timestamp":1289952000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>The objective of this study was to evaluate inter-individual variability in absorbed and internal doses after multi-route exposure to drinking water contaminants (DWC) in addition to the corresponding variability in equivalent volumes of ingested water, expressed as liter-equivalents (LEQ). A multi-route PBPK model described previously was used for computing the internal dose metrics in adults, neonates, children, the elderly and pregnant women following a multi-route exposure scenario to chloroform and to tri- and tetra-chloroethylene (TCE and PERC). This scenario included water ingestion as well as inhalation and dermal contact during a 30-min bathroom exposure. Monte Carlo simulations were performed and distributions of internal dose metrics were obtained. The ratio of each of the dose metrics for inhalation, dermal and multi-route exposures to the corresponding dose metrics for the ingestion of drinking water alone allowed computation of LEQ values. Mean BW-adjusted LEQ values based on absorbed doses were greater in neonates regardless of the contaminant considered (0.129\u20130.134 L\/kg BW), but higher absolute LEQ values were obtained in average adults (3.6\u20134.1 L), elderly (3.7\u20134.2 L) and PW (4.1\u20135.6 L). LEQ values based on the parent compound\u2019s AUC were much greater than based on the absorbed dose, while the opposite was true based on metabolite-based dose metrics for chloroform and TCE, but not PERC. The consideration of the 95th percentile values of BW-adjusted LEQ did not significantly change the results suggesting a generally low intra-subpopulation variability during multi-route exposure. Overall, this study pointed out the dependency of the LEQ on the dose metrics, with consideration of both the subpopulation and DWC.<\/jats:p>","DOI":"10.3390\/ijerph7114002","type":"journal-article","created":{"date-parts":[[2010,11,17]],"date-time":"2010-11-17T11:34:35Z","timestamp":1289993675000},"page":"4002-4022","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["An Assessment of the Interindividual Variability of Internal Dosimetry during Multi-Route Exposure to Drinking Water Contaminants"],"prefix":"10.3390","volume":"7","author":[{"given":"Mathieu","family":"Valcke","sequence":"first","affiliation":[{"name":"D\u00e9partement de sant\u00e9 environnementale et sant\u00e9 au travail, Universit\u00e9 de Montr\u00e9al, CP 6128, Succursale Centre-Ville, Montr\u00e9al, Qu\u00e9bec, H3C 3J7, Canada"},{"name":"Institut national de sant\u00e9 publique du Qu\u00e9bec, 190 Boulevard Cr\u00e9mazie Est, Montr\u00e9al, Qu\u00e9bec, H2P 1E2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kannan","family":"Krishnan","sequence":"additional","affiliation":[{"name":"D\u00e9partement de sant\u00e9 environnementale et sant\u00e9 au travail, Universit\u00e9 de Montr\u00e9al, CP 6128, Succursale Centre-Ville, Montr\u00e9al, Qu\u00e9bec, H3C 3J7, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2010,11,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"293","DOI":"10.1016\/0273-2300(91)90069-8","article-title":"Standard setting processes and regulations for environmental contaminants in drinking water: state versus federal needs and viewpoints","volume":"13","author":"Sidhu","year":"1991","journal-title":"Regul. 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