남지영 1) , 김혜진 2) , 박선민 3) , 최수현 4) , 정혜인 5) , 김민정 6) , 이민경 7) The influence of water drinking on oral management behavior and bad breath in college students

This study analyzed the concentration of the heavy metals(Cd, Hg, iAs) of urine(n=576) from May, 2007 to Oct 2007. The subject was residents in G, Y, H industrial area, Jeollanam-do, in which exposure due to the adjacency of the industrial complex. As to the heavy metal concentration in the urine of the residents in the whole exposed region and the comparing region, the content of cadmium, mercury, and inorganic arsenic in the exposed region group were 1.23, 1.85, and 8.80 µg/g_ct respectively, and those of the comparing region group were 1.87, 2.00, and 8.93 µg/g_ct respectively, which indicates that the concentration of the comparing group was higher than that of the exposed group. The heavy metal concentration for each age group increased in proportion to age except those under 10 for some substances(p<0.01). As to geometric mean concentration cadmium and inorganic arsenic in urine according to the smoking history of the subject, the concentration of the smoking group and the non-smoking group were 1.65 µg/g_ct and 9.13 µg/g_ct respectively, while those of the non-smoking group were 1.47 µg/g_ct and 8.91 µg/g_ct respectively, which indicates that the former is higher than the latter. As to the inorganic arsenic concentration in urine according to the food preference, in order of vegetable, fish, and meat showed high concentration (p<0.01). To clarify the factors affecting the heavy metal concentration in urine among the subjects, the multiple regression analysis was conducted. As a result, it turned out that as to cadmium content in urine, gender, age, drinking, and smoking have influence on the subjects, with explanatory adequacy of 37.5 %.

This research had been conducted from May to October 2007, studying 110 residents of G, Y, H industrial area in Jun-nam province. It is designed to understand the difference in levels of indoor, outdoor and personal exposure to VOCs(benzene, toluene, Ethylbenzene) and a health risk assessment was conducted to see if there was any fatal cause from carcinogenic or non -carcinogenic elements from a case group and a control group in all areas as well as each different area. In the case of benzene in the air, the geometric levels for the case group are indoor, outdoor and personal exposure; a higher than for the control group. As a results of the Monte -Carlo study about benzene, it shows that the case group's carcinogenicity is higher than that of the control group and it also shows that, on the CTE, RME condition and Monte -Carlo analysis, all subjects are seen to exceed the carcinogenicity tolerance 10 -6 of US EPA. In the case of toluene, ethylbenzene on the CTE, RME condition and Monte -Carlo analysis, these do not exceed the non -carcinogenic standard of 1, but toluene in RME condition for both groups' personal exposure and the indoor and personal exposure of ethylbenzene in Monte -Carlo show that these seem to exceed the standard.

Objectives: The purpose of this study is to investigate the mass concentration of nanoparticles and understand the characteristics of elements of heavy metal concentrations within nanoparticles in the air using Micro-Orifice Uniform Deposit Impactor Model-110 (MOUDI-110), based on indoor and outdoor air. . Mann-Whitney U tests showed that the difference between the indoors and the outdoors was statistically meaningful in terms of particles of 0.056 µm or less (p<0.05) in size. These results are possibly influenced by the use of printers and duplicators as the factor that increased the concentration of nanoparticles. In seasonal concentration distribution, the level was higher during the summer compared to in the autumn. Those of 0.056 µm or less in size presented a statistically meaningful difference during the summer (p<0.05). These results may be influenced by photochemical event as the factor that makes the levels high. Regarding zinc, among the other heavy metals, the fine particles ranged in size from 0.056 µm to 0.10 µm and those of 0.056 µm or less recorded 1.699 ng/m 3 and 1.189 ng/m 3 in the outdoors. In the indoors, the levels were lower, with 0.745 ng/m 3 and 0.617 ng/m Conclusion: This study indicates the result of an examination of nano-sized particles and heavy metal concentrations. It will provide useful data for the determination of basic nanoparticle standards in the future. †