• Journal of Environmental Health Sciences
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• v.47 no.2
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• pp.155-165
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• 2021

Objectives: Acute exposure to high concentrations of chemicals can occur when a chemical accident takes place. As such exposure can cause ongoing environmental pollution, such as in the soil and groundwater, there is a need for a tool that can assess health effects in the long term. The purpose of this study was assessing the health risks of residents living near a chemical accident site due to long-term exposure while considering the temporal concentration changes of the toxic chemicals leaked during the accident until their extinction in the environment using a multimedia environmental dynamics model. Methods: A health risk assessment was conducted on three cases of formaldehyde chemical accidents. In this study, health risk assessment was performed using a multimedia environmental dynamics model that considers the behavior of the atmosphere, soil, and water. In addition, the extinction period of formaldehyde in the environment was regarded as extinction in the environment when the concentration in the air and soil fell below the background concentration prior to the accident. The subjects of health risk assessment were classified into four groups according to age: 0-9 years old, 10-18 years old, 19-64 years old, and over 65 years old. Carcinogenic risk assessment by respiratory exposure and non-carcinogenic risk assessment by soil intake were conducted as well. Results: In the assessment of carcinogenic risk due to respiratory exposure, the excess carcinogenic risk did not exceed 1.0×10-6 in all three chemical accidents, so there was no health effect due to the formaldehyde chemical accident. As a result of the evaluation of non-carcinogenic risk due to soil intake, none of the three chemical accidents had a risk index of 1, so there was no health effect. For all three chemical accidents, the excess cancer risk and hazard index were the highest in the age group 0-9. Next, 10-18 years old, 65 years old or older, and 19-64 years old showed the highest risk. Conclusion: This study considers environmental changes after a chemical accident occurs and until the substance disappears from the environment. It also conducts a health risk assessment by reflecting the characteristics of the long-term persistence and concentration change over time. It is thought that it is of significance as a health risk assessment study reflecting the exposure characteristics of the accident substance for an actual chemical accident.

• Journal of Soil and Groundwater Environment
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• v.26 no.3
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• pp.37-49
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• 2021

There is domestic Soil Contamination Warning Standard (SCWS) as remediation standard concentration of contaminated soils. No risk should be observed at soil concentration less than SCWS. Therefore, SCWS was evaluated to confirm the risk assessment. Background Concentration of Soil (BGC) and target remediation concentration were also assessed. The results show that Excess Cancer Risk (ECR) of SCWS was the highest in the groundwater intake pathway (Adult: 6.27E-04, Child: 2.81E-04). Total Cancer Risk (TCR) was 7.76E-04 and 4.30E-04 for adult and child, exceeding reference value (10^-6). Hazard Quotient (Non-Carcinogenic Risk, HQ) was the highest in the indoor air inhalation pathway (Adult: 3.64E+03, Child: 8.74E+02). Hazard Index (Total Non-Carcinogenic Risk, HI) exceeded reference value 1. ECR of the BGC was the highest in the groundwater intake pathway (Adult: 1.71E-04, Child: 7.67E-05). TCR was 2.12E-04 for adults and 1.17E-04 for children, exceeding the reference value (10^-6). HQ was the highest in groundwater intake pathway (Adult: 4.10E-01, Child: 1.84E-01). HI was lower than reference value 1 (Adult: 4.78E-01, Child: 2.50E-01). The heavy metal affecting ECR was Arsenic (As). The remediation-concentration of As was 7.14 mg/kg which is higher than BGC (6.83 mg/kg). TCR of As should be less than reference value (10^-6), but it was higher for all of SCWS, BGC and target remediation concentration. Therefore, it is suggested that risk assessment factors should be re-evaluated to fit domestic environmental settings and SCWS should be induced to satisfy the risk assessment.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2429-2432
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• 2013

Background and Objectives: Yanting in Sichuan Province is one of the highest risk areas of esophageal cancer (EC) in the world. We here summarize the epidemiology of EC in Yanting using data from the national screening programme during 2006-2011. Methods: Random cluster sampling was used to select a proportion of natural villages from six towns in Yanting, and residents aged 40-69 years old were invited for screening. Participants were screened using endoscopy with iodine staining and then confirmed by histological examinations. Results: The overall detection rates of low-grade hyperplasia (LH), moderate hyperplasia (MH), high-grade hyperplasia (HH), carcinoma in situ (CIS), intramucosal carcinoma (IC) and invasive carcinoma (INC) were 5.33%, 1.28%, 0.68%, 0.15%, 0.06% and 0.29%, respectively. The detection rates of LH, MH, HH and INC increased with age, reaching the peak among those aged 60-65 years, and the prevalences of LH and MH were higher among men than among women. In addition, the detection rates of hyperplasia were much higher in mountainous than in hilly areas. Conclusions: Among the high risk population, there are a great number of people with early-stage EC or precancerous conditions who do not have presenting symptoms. In particular, the elderly, men, or those living in mountainous areas are the most vulnerable population. It is therefore important to reinforce health education and screening services among such high risk populations.

• Journal of Gastric Cancer
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• v.20 no.3
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• pp.267-276
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• 2020

Purpose: The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) risk calculator is useful in predicting postoperative adverse events. However, its accuracy in specific disorders is unclear. We validated the ACS NSQIP risk calculator in patients with gastric cancer undergoing curative laparoscopic surgery. Materials and Methods: We included 207 consecutive early gastric cancer patients who underwent laparoscopic gastrectomy between January 2018 and January 2019. The preoperative characteristics and risks of the patients were reviewed and entered into the ACS NSQIP calculator. The estimated risks of postoperative outcomes were compared with the observed outcomes using C-statistics and Brier scores. Results: Most of the patients underwent distal gastrectomy with Roux-en-Y reconstruction (74.4%). We did not observe any cases of mortality, venous thromboembolism, urinary tract infection, renal failure, or cardiac complications. The other outcomes assessed were complications such as pneumonia, surgical site infections, any complications requiring re-operation or hospital readmission, the rates of discharge to nursing homes/rehabilitation centers, and the length of stay. All C-statistics were <0 and the highest was for pneumonia (0.65; 95% confidence interval: 0.58-0.71). Brier scores ranged from 0.01 for pneumonia to 0.155 for other complications. Overall, the risk calculator was inconsistent in predicting the outcomes. Conclusions: The ACS NSQIP surgical risk calculator showed low predictive ability for postoperative adverse events after laparoscopic gastrectomy for patients with early gastric cancer. Further research to adjust the risk calculator for these patients may improve its predictive ability.

• Safety and Health at Work
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• v.4 no.1
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• pp.71-74
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• 2013

Here, we present a case of lung cancer in a 48-year-old male horse trainer. To the best of our knowledge, this is the first such case report to include an exposure assessment of respirable crystalline silica (RCS) as a quartz. The trainer had no family history of lung cancer. Although he had a 15 pack/year cigarette-smoking history, he had stopped smoking 12 years prior to his diagnosis. For the past 23 years, he had performed longeing, and trained 7-12 horses per day on longeing arena surfaces covered by recycled sands, the same surfaces used in race tracks. We investigated his workplace RCS exposure, and found it to be the likely cause of his lung cancer. The 8-hour time weight average range of RCS was 0.020 to $0.086mg/m^3$ in the longeing arena. Horse trainers are exposed to RCS from the sand in longeing arenas, and the exposure level is high enough to have epidemiological ramifications for the occupational risk of lung cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.7
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• pp.4447-4453
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• 2013

Purpose: To investigate the risk factors for anastomotic leakage (AL) after anterior resection for rectal cancer with a double stapling technique. Patients and Methods: Between January 2004 and December 2011, 753 consecutive patients in Jiangsu Cancer Hospital and Research Institute diagnosed with rectal cancer and undergoing anterior resection with a double stapling technique were recruited. All patients experienced a total mesorectal excision (TME) operation. Additionally, decrease of postoperative tumor supplied group of factors (TSGF), which have not been reported before, was proposed as a new indicator for AL. Univariate and multivariate analysis were performed to determine risk factors for AL. Results: AL was detected in 57 (7.6%) of 753 patients with rectal cancer. The diagnosis of anastomotic leakage was confirmed between the 6th and 12th postoperative day (POD; mean 8th POD). After univariate analysis and multivariate analysis, age (p<0.001), gender (p=0.002), level of anastomosis (p<0.001), preoperative body mass index (BMI) (p=0.001) and reduction of TSGF in 5th POD was less than 10 ${\mu}/ml$ (p<0.001) were selected as 5 independent risk factors for AL. It was also indicated that a temporary defunctioning transverse ileostomy (p=0.04) would decrease the occurrence of AL. Conclusion: AL after anterior resection for rectal carcinoma is related to elderly status, low level site of the tumor (below the peritoneal reflection), being male, preoperative BMI and the decrease of TSGF in $5^{th}$ POD is less than 10 ${\mu}/ml$. Preventive ileostomy is advisable after TME for low rectal tumors to prevent AL.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.13
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• pp.5371-5375
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• 2014

Background: An accurate assessment of potential lymph node metastasis is important for the appropriate treatment of early gastric cancers. Therefore, this study analyzed predictive factors associated with lymph node metastasis and identified differences between mucosal and submucosal gastric cancers. Materials and Methods: A total of 518 early gastric cancer patients who underwent radical gastrectomy were reviewed in this study. Clinicopathological features were analyzed to identify predictive factors for lymph node metastasis. Results: The rate of lymph node metastasis in early gastric cancer was 15.3% overall, 3.3% for mucosal cancer, and 23.5% for submucosal cancer. Using univariate analysis, risk factors for lymph node metastasis were identified as tumor location, tumor size, depth of tumor invasion, histological type and lymphovascular invasion. Multivariate analysis revealed that tumor size >2 cm, submucosal invasion, undifferentiated tumors and lymphovascular invasion were independent risk factors for lymph node metastasis. When the carcinomas were confined to the mucosal layer, tumor size showed a significant correlation with lymph node metastasis. On the other hand, histological type and lymphovascular invasion were associated with lymph node metastasis in submucosal carcinomas. Conclusions: Tumor size >2 cm, submucosal tumor, undifferentiated tumor and lymphovascular invasion are predictive factors for lymph node metastasis in early gastric cancer. Risk factors are quite different depending on depth of tumor invasion. Endoscopic treatment might be possible in highly selective cases.

• Journal of Radiation Protection and Research
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• v.48 no.2
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• pp.90-99
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• 2023

Background: Quantitative risk assessments should be accompanied by uncertainty analyses of the risk models employed in the calculations. In this study, we aim to develop a computational code named SUMRAY for use in cancer risk projections from radiation exposure taking into account uncertainties. We also aim to make SUMRAY publicly available as a resource for further improvement of risk projection. Materials and Methods: SUMRAY has two versions of code written in R and Python. The risk models used in SUMRAY for all-solid-cancer mortality and incidence were those published in the Life Span Study of a cohort of the atomic bomb survivors in Hiroshima and Nagasaki. The confidence intervals associated with the evaluated risks were derived by propagating the statistical uncertainties in the risk model parameter estimates by the Monte Carlo method. Results and Discussion: SUMRAY was used to calculate the lifetime or time-integrated attributable risks of cancer under an exposure scenario (baseline rates, dose[s], age[s] at exposure, age at the end of follow-up, sex) specified by the user. The results were compared with those calculated using another well-known web-based tool, Radiation Risk Assessment Tool (RadRAT; National Institutes of Health), and showed a reasonable agreement within the estimated confidential interval. Compared with RadRAT, SUMRAY can be used for a wide range of applications, as it allows the risk projection with arbitrarily specified risk models and/or population reference data. Conclusion: The reliabilities of SUMRAY with the present risk-model parameters and their variance-covariance matrices were verified by comparing them with those of the other codes. The SUMRAY code is distributed to the public as an open-source code under the Massachusetts Institute of Technology license.

• Journal of Environmental Impact Assessment
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• v.8 no.2
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• pp.1-8
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• 1999

The research centers on the concentration profile and risk assessment of toxic metals for ambient air in Taejon industrial complex. Airborne concentrations of each toxic metal for risk assessment were obtained from 2-year sampling by high volume air sampler and analysis by ICP-MS and ICP-AES in the complex. The long-term arithmetic mean of human carcinogen, arsenic, hexavalent chromium and nickel subsulfide was 5.53, 2.16 and $3.46ng/m^3$ while the mean of probable human carcinogen, beryllium, cadmium and lead was 0.08, 2.35, $293.29ng/m^3$, respectively. And the long-term arithmetic mean concentration of non-carcinogenic metal, manganese was $55.91ng/m^3$. The point risk estimate for the inhalation of carcinogenic metals was $3.6{\times}10^{-5}$, which was higher than a risk standard of $10^{-5}$. About 75% of the cancer risk was to the inhalation of human carcinogen, arsenic. Thus, it is necessary to properly manage arsenic risk in Taejon industrial complex. The point hazard index by the inhalation of manganese was 1.1. Therefore, an investigation into Taejon industrial complex is needed to obtain more fine long-term concentration data for airborne non-carcinogenic metals including manganese.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.441-447
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• 2013

Background: Prior studies examining the relation between diabetes mellitus (DM) and prostate cancer risk have reported controversial findings. We examined this association by conducting a detailed meta-analysis of the peer-reviewed literature. Methods: A comprehensive search for articles of MEDLINE and EMBASE databases and bibliographies of retrieved articles published up to November, 2012 was performed. Methodological quality assessment of the trials was based on the Newcastle-Ottawa Scaleq and the meta-analysis was performed using STATA 12.0. Dose-response regression was conducted with SPSS 19.0. Results: We included 29 studies in the meta-analysis (13 case-control studies, 16 cohort studies), and found an inverse association between DM and prostate cancer (relative risk (RR) 0.84, 95% confidence interval (CI), 0.78-0.91). An inverse association was also observed in non-Asian populations (RR 0.81, 95% CI 0.76-0.87) and population-based studies (RR 0.80, 95% CI 0.77-0.91). No statistical significance was found of the association between prostate cancer risk and the duration of DM (p=0.338), and risk seemed not related with the age of DM diagnosis. Conclusions: This study suggested an inverse relationship between DM and prostate cancer, but without links to duration of disease or age of diagnosis.