• Journal of Environmental Health Sciences
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• v.49 no.6
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• pp.324-333
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• 2023

Background: Human exposure to phthalates in indoor environments occurs via dermal absorption, oral ingestion of indoor dust, and inhalation of indoor air. However, systematic studies to investigate the exposure rate to phthalates among the three exposure routes in indoor environments are currently limited. Objectives: A theoretical exposure ratio between inhalation and oral exposure was calculated based on the total amount of di(2-ethyl-hexyl) phthalate (DEHP) emitted into indoor air and deposited into floor dust in a test house. Methods: Flooring and wallpaper containing DEHP were installed in a test house and the concentration of DEHP in both indoor air and floor dust were monitored for five months. Based on the measured DEHP concentrations, the theoretical total amount ratio of DEHP that could be exposed through inhalation and oral ingestion was calculated. Results: Considering the period of operation in the test house, the theoretical total amount of DEHP through inhalation and oral ingestion exposures in the entire test house space was calculated to be 0.014 mg and 5.5 mg, respectively. The exposure ratio of the two routes between inhalation and oral exposure corresponding to the total DEHP amount in flooring and wallpaper was 6.0×10^-7% and 2.3×10^-4%, indicating that theoretical oral exposure to DEHP is approximately 380 times higher than inhalation. Conclusions: Monitoring results from a test house has shown that oral exposure is the main exposure route for DEHP in indoor environments. The experimental design employed in this study and theoretical exposure ratio obtained can be applied to investigate actual exposure to DEHP and to determine the exposure characteristics of various types of semi-volatile organic compounds.

• Journal of Preventive Medicine and Public Health
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• v.57 no.2
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• pp.185-196
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• 2024

Objectives: Excess mortality associated with long-term exposure to fine particulate matter (PM_2.5) has been documented. However, research on the disease burden following short-term exposure is scarce. We investigated the cause-specific mortality burden of short-term exposure to PM_2.5 by considering the potential non-linear concentration-response relationship in Korea. Methods: Daily cause-specific mortality rates and PM_2.5 exposure levels from 2010 to 2019 were collected for 8 Korean cities and 9 provinces. A generalized additive mixed model was employed to estimate the non-linear relationship between PM_2.5 exposure and cause-specific mortality levels. We assumed no detrimental health effects of PM_2.5 concentrations below 15 ㎍/m³. Overall deaths attributable to short-term PM_2.5 exposure were estimated by summing the daily numbers of excess deaths associated with ambient PM_2.5 exposure. Results: Of the 2 749 704 recorded deaths, 2 453 686 (89.2%) were non-accidental, 591 267 (21.5%) were cardiovascular, and 141 066 (5.1%) were respiratory in nature. A non-linear relationship was observed between all-cause mortality and exposure to PM_2.5 at lag0, whereas linear associations were evident for cause-specific mortalities. Overall, 10 814 all-cause, 7855 non-accidental, 1642 cardiovascular, and 708 respiratory deaths were attributed to short-term exposure to PM_2.5. The estimated number of all-cause excess deaths due to short-term PM_2.5 exposure in 2019 was 1039 (95% confidence interval, 604 to 1472). Conclusions: Our findings indicate an association between short-term PM_2.5 exposure and various mortality rates (all-cause, non-accidental, cardiovascular, and respiratory) in Korea over the period from 2010 to 2019. Consequently, action plans should be developed to reduce deaths attributable to short-term exposure to PM_2.5.

• Journal of the Korean Society of Safety
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• v.24 no.5
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• pp.6-12
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• 2009

This study performed an experiment for the danger of an electric shock in the human body, which is directly touched or approached to the exposure of buried metals in a leak caused by certain ground faults at a buried cable in street lamp. In the results of the experiment, the dangerous of electric shocks due to the earth specific resistance and wet and submersion of the earth surface represents a high level as the human body is directly touched to the buried metal at a leak point. In addition, it can be seen that the safety of the human body is influenced by the earth specific resistance, separated distance from buried metals, and shape of buried metals at around the leak point.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.11
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• pp.96-103
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• 2013

In this paper, resonant wireless power transfer systems are designed with double loop resonant coils for the resonant frequency of 150kHz. The transfer efficiency characteristics is analyzed according to the coil size, and the distance and misalignment between the coils. Then the change in efficiency is investigated when a human model is located between the resonant coils using the homogeneous human phantom of IEC-62311 standard. Also, in order to assess the safety of the wireless power transfer system, the induced current density inside the human model is calculated when it is exposed to the magnetic field of a plane wave and resonant coil. Then, the results are compared with the exposure limits in the EMF (electromagnetic field) safety guidelines.

• Progress in Medical Physics
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• v.5 no.2
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• pp.77-85
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• 1994

In this paper, the vibration response characteristics of individual's subjective are studied to whole-body and hand-arm induced vibration. For defining limits of vibration exposure to human, experimental data are investigated in a set of vibration criteria specified in ISO Standard 2631. Instrumentation requirements for evaluation of the responses of humans to vibration according to these criteria are discribed.

• Journal of the Korean Society of Safety
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• v.17 no.3
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• pp.22-29
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• 2002

The safety device of infrared type for dangerous machine being used currently has a harmful effect on human's eye and skin. In this paper we explain about the characteristics of lasr source and analyze the amount of harmfulness on human's eye by simulation method. We used the datas given by ANSI in this simulation.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.200-200
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• 2002

Cadmium (Cd) is an environmental pollutant and categorized as a human carcinogen, which has a tendency to accumulate in the human body. The level of Cd in renal cortex and liver are good indicators as an index of Cd exposure in general population. Geometric mean concentration of Cd is 27.4 and 3.1 /g wet weight in renal cortex and liver, respectively, in Korean. Cd is toxic to a number of tissues, notably the liver, kidney, testis, lung, lymphoid tissue and lung. (omitted)

• Journal of Biosystems Engineering
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• v.17 no.4
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• pp.314-325
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• 1992

This paper reviews some relevant criteria for the evaluation of ride quality of agricultural tractors. Although there still exist many deficiences and shortcomings, ISO 2631 'Guide for the evaluation of human exposure to whole body vibration' may be the most pertinent criterion to the ride quality evaluation of tractors. The effects of ride vibrations on the human health and performance were also reviewed and summarized in general terms.

• Asian Journal of Atmospheric Environment
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• v.1 no.1
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• pp.28-35
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• 2007

Accumulated epidemiological and animal studies have suggested that prolonged exposure to ambient particulate matter (PM) is associated with an increased risk of cardiovascular disease and pulmonary dysfunction. While diesel exhaust particles (DEP) contain large variety of compounds, polycyclic aromatic hydrocarbons (PAHs) are a dominant component contaminated in DEP. This article reviews effects of two PAH quinones, 9,10-phenanthraquinone (9,10-PQ) and l,2-naphthoquinone (l,2-NQ), on vascular and respiratory systems.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.123.2-123.2
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• 2003

The cellular mechanisms by which excess exposure to the excitatory neurotransmitter glutamate can produce neuronal injury are unknown. In this study, we found that glutamate induced cell death at IC (50) of 100 microM on the cultured human SH-SY5Y neuroblastoma cells. It has been hypothesized that glutamate excitotoxicity is related with the elevation of calcium (Ca) levels. To determine the dependence of glutamate neurotoxicity on Ca environment, extracellular (EDTA) and intracellular (BAPTA/AM) chelator were used. (omitted)