Dataset Information

Determination of hand soil loading, soil transfer, and particle size variations after hand-pressing and hand-mouthing activities.

ABSTRACT: Hand-pressing trials and hand-to-mouth soil transfer experiments were conducted to better understand soil loadings, soil transfer ratios for three mouthing activities, and variations in particle size distributions under various conditions. Results indicated that sand caused higher soil loadings on the hand than clay. When the moisture level of clay soil exceeded its liquid limit, soil loadings also increased. Greater pressing pressures also led to larger clay loadings. Clay with a moisture content close to its plastic limit caused the smallest soil loadings due to strong soil cohesion. Particle sizes of the transferred clay were larger than that of the original clay, indicating that hand-pressing and the pressure exerted may have enhanced clay particles of larger sizes adhering onto the hand. Nevertheless, the sizes of most particles that adhered to the hand were still smaller than 150??m. Higher pressing pressures and greater moisture contents resulted in larger soil loadings on the hand, and transfer ratios became smaller. Transfer ratios from palm-licking with clay particles were smaller than those from finger-mouthing, which may have been due to finer particles that more readily adhered to the skin of the palm and that were transferred from the hand to the mouth with greater difficulty.

SUBMITTER: Hsi HC

PROVIDER: S-EPMC6147011 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Determination of hand soil loading, soil transfer, and particle size variations after hand-pressing and hand-mouthing activities.

Hsi Hsing-Cheng HC Hu Ching-Yao CY Tsou Ming-Chien MC Hu Han-Jung HJ Özkaynak Halûk H Bradham Karen K Hseu Zeng-Yei ZY Dang Winston W Chien Ling-Chu LC

The Science of the total environment 20180202

Hand-pressing trials and hand-to-mouth soil transfer experiments were conducted to better understand soil loadings, soil transfer ratios for three mouthing activities, and variations in particle size distributions under various conditions. Results indicated that sand caused higher soil loadings on the hand than clay. When the moisture level of clay soil exceeded its liquid limit, soil loadings also increased. Greater pressing pressures also led to larger clay loadings. Clay with a moisture conte ...[more]

PMID: 29426209

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Dataset Information

Determination of hand soil loading, soil transfer, and particle size variations after hand-pressing and hand-mouthing activities.

Publications

Determination of hand soil loading, soil transfer, and particle size variations after hand-pressing and hand-mouthing activities.

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