• The Korean Journal of Malacology
• /
• v.22 no.2
• /
• pp.151-155
• /
• 2006

Proportion of Tegillarca granosa surviving after 2-6 hrs air exposure with 12 hrs interval at $20^{\circ}C$ and $28^{\circ}C$ for 20 days showed 85-100%, 80-100%, respectively. The survival rate was somewhat lower at high temperature but not significant (p < 0.05). Subsequent exposures for 7-9 days showed survival rate of 8.0-24.1% at $20^{\circ}C$ and $28^{\circ}C$. Oxygen consumption rates and filtration rates were significantly higher for 4 to 6 hrs exposures, compared with the preceding exposures. On the other hand, at $28^{\circ}C$, oxygen consumption rates in adult granular ark for 6 hrs exposure during 20 days had significantly decreased. Filtration rates in study groups increased a little over extended period of exposure, compared with those in control groups, and were similar irrelevant to the time of exposure and size of experimental animals. It is concluded, in view of their viability and oxygen consumption rate during air exposure, that ark shells have quite a high resistance to air exposure with their limited range of responses.

• Journal of Preventive Medicine and Public Health
• /
• v.47 no.5
• /
• pp.253-257
• /
• 2014

Arsenic is a ubiquitous, naturally occurring metalloid that may be a significant risk factor for cancer after exposure to contaminated drinking water, cigarettes, foods, industry, occupational environment, and air. Among the various routes of arsenic exposure, drinking water is the largest source of arsenic poisoning worldwide. Arsenic exposure from ingested foods usually comes from food crops grown in arsenic-contaminated soil and/or irrigated with arsenic-contaminated water. According to a recent World Health Organization report, arsenic from contaminated water can be quickly and easily absorbed and depending on its metabolic form, may adversely affect human health. Recently, the US Food and Drug Administration regulations for metals found in cosmetics to protect consumers against contaminations deemed deleterious to health; some cosmetics were found to contain a variety of chemicals including heavy metals, which are sometimes used as preservatives. Moreover, developing countries tend to have a growing number of industrial factories that unfortunately, harm the environment, especially in cities where industrial and vehicle emissions, as well as household activities, cause serious air pollution. Air is also an important source of arsenic exposure in areas with industrial activity. The presence of arsenic in airborne particulate matter is considered a risk for certain diseases. Taken together, various potential pathways of arsenic exposure seem to affect humans adversely, and future efforts to reduce arsenic exposure caused by environmental factors should be made.

• Journal of Environmental Science International
• /
• v.13 no.7
• /
• pp.627-635
• /
• 2004

Evaluated were household THMs exposure associated with the use of municipal tap water treated with chlorine and with ozone-chlorine. The current study measured the THMs concentrations in the tap water and indoor and outdoor air in the two types of household, along with an estimation of THMs exposure from water ingestion, showering, and the inhalation of indoor air. Chloroform was the most abundant THMs in all three media, yet no bromoform was detected in any sample. Contrary to previous findings, the fall water THMs concentrations exhibited no significant difference between the chlorine and ozone-chlorine treated water. However, the spring median chloroform concentration in the tap water treated with chlorine (17.6 ppb) was 1.3 times higher than that in the tap water treated with ozone-chlorine (13.4 ppb). It is suggested that the effects of the water parameters should be considered when evaluating the advantage of ozone-chlorine disinfection for THMs formation over chlorine disinfection. The indoor air THMs concentration trend was also consistent with the water concentration trend, yet the outdoor air THMs concentrations did not differ significantly between the two types of household. The indoor to outdoor air concentration ratios were comparable with previous studies. The THMs exposure estimates from water ingestion, showering, and the inhalation of indoor air suggested that, for the residents living in the surveyed households, their exposure to THMs in the home was mostly associated with their household water use, rather than the indoor air. The THMs exposure estimates from tap water ingestion were similar to those from showering.

• Journal of Environmental Health Sciences
• /
• v.48 no.3
• /
• pp.131-137
• /
• 2022

Public interest has been increasing the focus on the management of exposure to pollutants and the related health effects. This study reviewed exposure assessment methodologies and addressed future directions. Exposure can be assessed by direct (exposure monitoring) or indirect approaches (exposure modelling). Exposure modelling is a cost-effective tool to assess exposure among individuals, but direct personal monitoring provides more accurate exposure data. There are several population exposure models: stochastic human exposure and dose simulation (SHEDS), air pollutants exposure (APEX), and air pollution exposure distributions within adult urban population in Europe (EXPOLIS). A South Korean population exposure model is needed since the resolution of ambient concentrations and time-activity patterns are country specific. Population exposure models could be useful to find the association between exposure to pollutants and adverse health effects in epidemiologic studies. With the advancement of sensor technology and the internet of things (IoT), exposure assessment could be applied in a real-time surveillance system. In the future, environmental health services will be useful to protect and promote human health from exposure to pollutants.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.30 no.2
• /
• pp.163-173
• /
• 2020

Objectives: The study was evaluated exposure variation and daily absorption level of cadmium, lead concentration of ambient air of monthly data from 1999 to 2017 for main exposure factor in outdoor workers. Methods: Based on the monthly data from 'The annual report of air quality in Korea from 1999 to 2018' in 'Air Korea' website in the Korean Ministry of Environment. The monthly data of PM_2.5, PM₁₀, cadmium, lead concentration of ambient air were recalculated to average, minimum, and maximum. And these data were combined to Asian-dust exposure data from 'The annual report of Asian-dust·smog in 2017' of National Institute of Meteorological Sciences in Korea. Results: Geometric mean(minimum-maximum) concentration in ambient air of monthly data were 0.0017 (ND-0.2015) mg/㎥ in cadmium and 0.0467(ND-0.8554) mg/㎥ in Pb from 1999 to 2017. Both of Cd and Pb concentration in ambient air showed the highest concentration in January and the lowest in August among annual variation from 1999 to 2017. PM₁₀ and PM_2.5 level showed the highest in March(PM₁₀) and February (PM_2.5) the lowest in August both of PM₁₀ and PM_2.5. Discussion: Based on exposure data and prior reports, daily Cd absorption was estimated to 0.013(ND-1.511) mg/day from respiration and 1.89 mg/day from daily food(25.2 mg/day of daily Cd intake). In case of Pb, daily absorption was estimated to 0.350(ND-6.416) mg/day from respiration and 1.38-1.71 mg/day from daily food intake. Conclusion: Cd and Pb with Asian-dust have high influential factor to increase the Cd and Pb exposure at Winter and Spring season in outdoor workers.

• Journal of Environmental Science International
• /
• v.22 no.1
• /
• pp.47-57
• /
• 2013

Studies evaluating the health effects of hazardous air pollutants assume that people's exposure to typical pollutant level is the same as specific regional pollutant level. However, depending on social and demographic factors, time-activity pattern of people can vary widely. Since most people live in indoor environments over 88% of the day, evaluating exposure to hazardous air pollutants is hard to characterize. Objective of this study was to estimate the exposure levels of university students of $NO_2$, VOCs(BTEX) and $PM_{10}$ using the scenarios with time-activity pattern and indoor concentrations. Using data from time-use survey of National Statistical Office in 2009, we investigated time-activity pattern of university students and hourly major action. A total of 1,057 university students on weekday and 640 on weekend spent their times at indoor house 13.04 hr(54.32%), other indoors 7.70 hr(32.06%), and transportation 2.36 hr(9.83%). Indoor environments in which university students spent their times were mainly house and school. Air pollutants concentrations of other indoor environments except house and school such as bar, internet cafe and billiard hall were higher than outdoors, indicating that indoor to outdoor ratios were above 1. According to three types of exposure scenarios, exposure to air pollutants could be reduced by going home after school.

• Clinical and Experimental Pediatrics
• /
• v.64 no.1
• /
• pp.3-11
• /
• 2021

There is a growing body of literature on the adverse health effects of ambient air pollution. Children are more adversely affected by air pollution due to their biological susceptibility and exposure patterns. This review summarized the accumulated epidemiologic evidence with emphasis on studies conducted in Korea and heterogeneity in the literature. Based on systematic reviews and meta-analyses, there is consistent evidence on the association between exposure to ambient air pollution and children's health, especially respiratory health and adverse birth outcomes, and growing evidence on neurodevelopmental outcomes. Despite these existing studies, the mechanism of the adverse health effects of air pollution and the critical window of susceptibility remain unclear. There is also a need to identify causes of heterogeneity between studies in terms of measurement of exposure/outcome, study design, and the differential characteristics of air pollutants and population.

• Journal of Environmental Impact Assessment
• /
• v.16 no.4
• /
• pp.267-275
• /
• 2007

In this study, relationship between the air pollution of Siheung city and the relative contribution of automobiles to the city's pollution was evaluated for the first time. Then, new air pollution exposure index was developed through simulation. Using the newly developed index, two different urban development scenarios were compared to present a sustainable urban development plan to reduce air pollution from the land utilization point of view. According to the result of this simulation, air quality of the city was found to be affected significantly by human activities. More populated area showed worse level of air quality. Any development in the city resulted in more automobile activity and deterioration of air quality. This simulation result thus explains that a rapid increase of automobiles accompanied by the land development near local roadsides in the city is the major cause of air pollution in Siheung city. In this study, if urban activities are vigorous in an area with high air pollution, people are more likely to be exposed to air pollutant under the bad environmental conditions. On the other hand, if urban activities are less vigorous in an area with high pollution or if urban activities are vigorous in an area with less pollution, the environmental condition was positive. The APEI (Air Pollution Exposure Index) was developed based on these considerations. Scenarios 1 and 2 were compared and analyzed using APEI. In result, scenario 1 is the case in which land is developed and used in an environmentally favorable manner. From this study, it was proved that the impact of air pollution on human health can be minimized with proper land use. The result form the current study can be used as the basic information to solve problems from improper land utilization and air pollution (by road traffic). It also can be utilized to evaluate air pollution level according to land use and road characteristics and to help to choose the best location of land use to comply with the road function and status.

• Proceedings of the Korea Air Pollution Research Association Conference
• /
• 2004.05a
• /
• pp.108-109
• /
• 2004

• Journal of ILASS-Korea
• /
• v.23 no.2
• /
• pp.81-89
• /
• 2018

The objective of this study is to estimate the level of exposure of traffic-related air pollutants (TRAPs) on the pedestrians in Seoul area. The road network's link-based pollutant emission was calculated by using a set of mobile source emission factor package and associated activity information. The population information, which is the number of pedestrian, was analyzed in conjunction with the link-based traffic emissions in order to quantify exposure level by selected 23 spots. We proposed the Exposure Intensity, which is defined by the amount of traffic emission and the population, to quantify the probability of exposure of pedestrian. Link-based traffic NOx and PM emissions vary by up to four times depending on the location of each spot. The Hot-spots is estimated to be around 1.8 times higher Exposure Intensity than the average of the 23 selected spots. The information of Exposure Intensity of each spot allows us to develop localized policies for air quality and health. Even in the same area, the Exposure Intensity over time also shows a large fluctuation, which gives suggestions for establishing site-specific counter-measures.