• Journal of Environmental Health Sciences
• /
• v.44 no.6
• /
• pp.556-562
• /
• 2018

Objectives: This study was conducted to investigate the boron concentrations in 30 slime products and estimate children's dermal exposure to boron. Methods: Thirty slime products from online and offline stores were purchased for boron analysis. The boron content of each slime sample was analyzed using ICP-OES. A nationwide survey was performed to determine use patterns of slimes by a home-visit survey of 10,000 children divided into three age groups: 0-2, 3-6, and 7-12 years. The dermal exposure to boron was calculated using an exposure algorithm for child slime users. Results: The proportion of the child population using slime was 45.8%, and the mean use frequency was $2.5{\pm}3.8$ per week (range: 0.08-35). Mean time spent playing with slime was $19.6{\pm}11.3min$ (range: 1-100). Twenty-five of the thirty slimes contained a boron concentration exceeding the EU limit for toys made with sticky material of 300 mg/kg. Dermal exposure ranged from $0.0008-13.78{\mu}g/kg/day$ with the maximum weight fractions of boron in the 30 products. The dermal exposure estimate was the highest in 7-12 years old group. Conclusion: Slime use among Korean children may cause high exposure to boron. Regulation is needed to minimize boron exposure from slime products.

• Korean Journal of Environmental Biology
• /
• v.35 no.4
• /
• pp.573-580
• /
• 2017

The oxicity assesment of Phenanthrene (PHE) has been investigated by using the rate (r) of survival and population growth in rotifer Brachionus plicatilis. The survival rate was determined after 24 h of exposure to PHE. The survival rate of PHE had no effect at a maximum of $300mg\;L^{-1}$. The r was determined after 72 h of exposure to PHE. It was observed that r in the controls (absence PHE) was greater than 0.5, but that it suddenly decreased with an increased concentration of PHE. PHE reduced r in a dose-dependent manner and a significant reduction occurred at a concentration of greater than $37.5mg\;L^{-1}$. The $EC_{50}$ value of r in PHE exposure was $63.7mg\;L^{-1}$. The no-observed-effect-concentration (NOEC) of r in PHE exposure was $18.8mg\;L^{-1}$. The lowest-observed-effect-concentration (LOEC) of r in the PHE exposure was $37.5mg\;L^{-1}$. From the results, the concentration of PHE (greater than $37.5mg\;L^{-1}$) has a toxic effect on the r of B. plicatilis in natural ecosystems. These results(including NOEC, LOEC and $EC_{50}$) might be useful for the Polycyclic aromatic hydrocarbons(PAHs) toxicity assessment in marine ecosystems.

• Journal of Environmental Health Sciences
• /
• v.45 no.3
• /
• pp.247-257
• /
• 2019

Objectives: The Korea Ministry of Environment regulates concentrations of hazardous air pollutants (HAPs) through Atmosphere Environmental Standards to protect public health from HAPs. However, simply determining the exceedance of HAP concentrations has several limitations and more comprehensive assessment is required. In addition, integrated risk assessment is needed considering exposure in all microenvironments, including outdoor as well as indoor environments. The purpose of this study was to assess the differences in risk by sub-population groups according to time-activity patterns and reported concentrations, as well as the lifetime risk for Koreans. Methods: In this study, we calculated time-weighted average exposure concentrations for benzene and $PM_{10}$ among preschool-age children, students, housewifes, workers, and the elderly using residential time and concentrations for indoor (house, school or workplace, other), outdoor, and transport by the meta-analysis method. The risk assessments were conducted by excess cancer risk and disease death risk using 1,000,000 Monte-Carlo simulations for probabilistic analysis. Results: Preschool-age children, students, housewifes, workers, and the elderly spent 91.9, 86.0, 79.8, 82.2, and 77.3% of their day in their house, workplace, or school, respectively. The more than 99% excess cancer risk for benzene exceed 1.0E-06 in all sub-populations and lifetime. The acute disease death risk for $PM_{10}$ for housewifes and workers for lifetime were 3.35E-04 and 3.18E-04, and chronic disease death risks were 2.84E-03 and 2.70E-03, respectively. Conclusions: The risk of benzene and $PM_{10}$ by sub-population group and for the lifetime of housewifes and workers were assessed. Benzene showed risky results for this study. All disease death risks of $PM_{10}$ were higher than 1.0E-04 and showed different risks by sub-population. This study can be used as a basis for lifetime exposure and risk assessment to benzene and $PM_{10}$.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.23 no.3
• /
• pp.229-242
• /
• 2013

Objectives: This study was designed to investigate the current status of the association of job-related information such as employment status, workplace environment, and hazard material exposures with health examination outcomes. Methods: The study used data from KNHANES 2007-2009 representing the three years of 2007-2009, which was conducted annually using a rolling sampling design that involved a complex, stratified, multistage, probability-cluster survey of a representative sample of the non-institutionalized civilian population in Korea. The final analytical sample consisted of 17,240 participants. Information on age, education, smoking history and alcohol intake was collected during the health interview. Job related information consisted of employment status, workplace environment, and hazardous material exposure. The selected indices of health examination were blood pressure, fasting glucose, blood cholesterol, HDL, SGOT, SGPT, and BUN. Results: In multiple logistic regression analysis using hypertension and pre-hypertension as dependent variables and job related categories as independent variables after covariate adjustments, the odds of hypertension and pre-hypertension were significantly lower in those with responsibility and power in their job activities. Interestingly, low odds for hypertension were observed among those who reported that their jobs were fast-paced. Conclusions: This study confirmed that some job-related categories in employment status, workplace environment, and hazardous material exposure had an association with health outcome status. It is worthwhile to comment that high responsibility and power in job activities were revealed as one of the important favorable factors to improve health condition of workers.

• Safety and Health at Work
• /
• v.9 no.2
• /
• pp.133-139
• /
• 2018

Background: Selecting priority occupational carcinogens is important for cancer prevention efforts; however, standardized selection methods are not available. The objective of this paper was to describe the methods used by CAREX Canada in 2015 to establish priorities for preventing occupational cancer, with a focus on exposure estimation and descriptive profiles. Methods: Four criteria were used in an expert assessment process to guide carcinogen prioritization: (1) the likelihood of presence and/or use in Canadian workplaces; (2) toxicity of the substance (strength of evidence for carcinogenicity and other health effects); (3) feasibility of producing a carcinogen profile and/or an occupational estimate; and (4) special interest from the public/scientific community. Carcinogens were ranked as high, medium or low priority based on specific conditions regarding these criteria, and stakeholder input was incorporated. Priorities were set separately for the creation of new carcinogen profiles and for new occupational exposure estimates. Results: Overall, 246 agents were reviewed for inclusion in the occupational priorities list. For carcinogen profile generation, 103 were prioritized (11 high, 33 medium, and 59 low priority), and 36 carcinogens were deemed priorities for occupational exposure estimation (13 high, 17 medium, and 6 low priority). Conclusion: Prioritizing and ranking occupational carcinogens is required for a variety of purposes, including research, resource allocation at different jurisdictional levels, calculations of occupational cancer burden, and planning of CAREX-type projects in different countries. This paper outlines how this process was achieved in Canada; this may provide a model for other countries and jurisdictions as a part of occupational cancer prevention efforts.

• Safety and Health at Work
• /
• v.11 no.4
• /
• pp.509-516
• /
• 2020

Background: Meta-analyses have shown firefighters to be at an increased risk of several cancer types. Occupational carcinogen exposure may explain these increased risks. This study aims to describe Norwegian fire departments' work conditions from 1950 until today, focusing on factors relevant for potential occupational carcinogen exposure. Methods: With the help of a reference group, we developed a questionnaire on topics related to occupational exposure to carcinogens for the period 1950-2018. Selected Norwegian fire departments provided department-specific responses. Results: Sixteen departments, providing fire services for 48% of the Norwegian population as of 2019 and mainly consisting of professional firefighters, responded to our questionnaire. The introduction of synthetic firefighting foams, more regular live fire training, the introduction of chemical diving, and a higher number of diesel-driven fire service vehicles were identified as changes thought to increase exposure to occupational carcinogens. Changes thought to decrease exposure included the switch from negative to positive pressure self-contained breathing apparatuses, the use of self-contained breathing apparatuses during all phases of firefighting, the use of ventilating fans during firefighting, increased attention to flammable materials used during live fire training, increased attention to handling and cleaning of turnout gear and other equipment, and installment of exhaust removal systems in apparatus bays. Conclusion: Norwegian fire departments' work conditions have seen several changes since 1950, and this could influence firefighters' occupational carcinogen exposure. A peak of carcinogen exposure may have occurred in the 1970s and 1980s before recent changes have reduced exposure.

• Clinical and Experimental Reproductive Medicine
• /
• v.13 no.2
• /
• pp.175-180
• /
• 1986

It has been reported that oral kallikrein therapy exerts a favourable effect on sperm motility in asthenozoospermic patients. In order to evaluate the efficacy of kallikrein on asthenozoospermia, a total of 20 subfertile male patients with varicocele, whose sperm counts were less than $40{\times}10^6/ml$ and sperm motility was less than 30%, was subjected to this clinical study (Table 1). They were divided into 2 study groups: 1) Varicocelectomy group consisted of 10 patients with varicocele (grade II-III) who underwent varicocelectomy. 2) Kallikrein group was composed of 10 patients with varicocele (grade I) who were given kallikrein orally 600 KU (kallikrein unit) daily divided 3 times after meal for 3 to 9 months. Semen analyses were repeated twice before the study, once a month during the study and twice after the study. Effective results designate that sperm parameters improved more than 30% from the basical levels after varicocelectomy or kallikrein exposure. Sperm counts increased from $32.5{\times}10^5/ml$ to $45.5{\times}10^6/ml$ after varicocelectomy in 3 patients and sperm motility increased from 25% to 38.5% after varicocelectomy in 3 patients. Pregnancy occurred in 2 patients of 3 responders and 1 patient of 7 non-responders 3 to 6 months after varicocelectomy in Varicocelectomy group. Sperm motility increased from 28% to 40.2% after kallikrein treatment in 3 patients. Pregnancy occurred in 2 patients of the 3 responders in Kallikrein group (Tables 2-3). There were no significant changes in volume and morphology in Varicocelectomy group before after varicocelectomy and no significant changes in volume, counts, and morphology before and after kallikrein exposure. No remarkable side effects were noted with kallikrein treatment.

• Ocean Science Journal
• /
• v.41 no.4
• /
• pp.211-219
• /
• 2006

A comparison was made of population of the economically important cockle Anadara (=Scapharca) broughtoni (Bivalvia, Arcidae) inhabiting different areas of the Razdolnaya River estuary at the head of Amurskii Bay (Peter the Great Gulf, East Sea). Also, changes in cockle population density and structure, as well as in cockle growth rates during the last 20 years were studied. In all years of investigation, the morphometrical parameters and growth rates of cockles were smaller at the sites located close to the River mouth than farther down-estuary. The differences can be attributed to higher concentration of suspended particulate matter, decreased salinity and water temperature, as well as a longer exposure to these unfavorable environmental factors at sites located close to the River mouth, compared to farther sites. For two decades, cockle population density had decreased by almost 30 times at some sites in the River estuary. The main reason for this population decline is commercial over-fishing of the cockle. Besides, for the last 20 years, linear parameters of the cockles in the population decreased approximately by 30% and weight parameters, almost two times. Cockle growth rates also decreased for this period. Evidently, these facts are due to the damaging effect of dredging.

• Asia Pacific Journal of Business Review
• /
• v.4 no.2
• /
• pp.23-33
• /
• 2020

Uzbekistan has been gradually integrating into the world economy since gaining its independence back in 1991. The need to integrate stems from the desire to advance the national economy and social well-being of population through importing advanced technologies or stimulating exports. However, opening up the country also meant exposure to increase in the mobility of its human capital. As a result, Uzbekistan has witnessed labor migration in and out of the country in the past couple of decades, driven by various causes, which is having inevitable social and economic implications for the country. Intensifying processes in contemporary international labor market make migration as a mechanism, which has a back-to-back impact onto and from economic development of a country. From developing countries' perspective, international labor migration is an instrument for reducing tension in national labor markets, decreasing high rates of unemployment and expanding sources of income. From developed countries' perspective, international labor migration helps solve demographic problems like decreasing number of population, aging of population and shortage of labor force. Thus, this processes turned into a mechanism or a system, which is not possible to ignore. Uzbekistan, in particular, is increasing its participation in the international labor market due to its high rates of population growth and young population.

• Annals of Occupational and Environmental Medicine
• /
• v.35
• /
• pp.6.1-6.15
• /
• 2023

Background: Polycyclic aromatic hydrocarbons (PAHs) are occupational and environmental pollutants generated by the incomplete combustion of organic matter. Exposure to PAHs can occur in various occupations. In this study, we compared PAH exposure levels among occupations based on 4 urinary PAH metabolites in a Korean adult population. Methods: The evaluation of occupational exposure to PAHs was conducted using Second Korean National Environmental Health Survey data. The occupational groups were classified based on skill types. Four urinary PAH metabolites were used to evaluate PAH exposure: 1-hydroxypyrene (1-OHP), 2-naphthol (2-NAP), 1-hydroxyphenanthrene (1-OHPHE), and 2-hydroxyfluorene (2-OHFLU). The fraction exceeding the third quartile of urinary concentration for each PAH metabolite was assessed for each occupational group. Adjusted odds ratios (ORs) for exceeding the third quartile of urinary PAH metabolite concentration were calculated for each occupational group compared to the "business, administrative, clerical, financial, and insurance" group using multiple logistic regression analyses. Results: The "guard and security" (OR: 2.949; 95% confidence interval [CI]: 1.300-6.691), "driving and transportation" (OR: 2.487; 95% CI: 1.418-4.364), "construction and mining" (OR: 2.683; 95% CI: 1.547-4.655), and "agriculture, forestry, and fisheries" (OR: 1.973; 95% CI: 1.220-3.191) groups had significantly higher ORs for 1-OHP compared to the reference group. No group showed significantly higher ORs than the reference group for 2-NAP. The groups with significantly higher ORs for 1-OHPHE than the reference group were "cooking and food service" (OR: 2.073; 95% CI: 1.208-3.556), "driving and transportation" (OR: 1.724; 95% CI: 1.059-2.808), and "printing, wood, and craft manufacturing" (OR: 2.255; 95% CI: 1.022-4.974). The OR for 2-OHFLU was significantly higher in the "printing, wood, and craft manufacturing" group (OR: 3.109; 95% CI: 1.335-7.241) than in the reference group. Conclusions: The types and levels of PAH exposure differed among occupational groups in a Korean adult population.