[Show abstract][Hide abstract] ABSTRACT: Human uncoupling proteins 2 and 3 (UCP2 and UCP3) are two mitochondrial proteins that are involved in the control of metabolism of fatty acid and possibly protect against oxidative damage. The aim of this study was to analyze genetic associations of four polymorphisms of the UCP2 and UCP3 genes with insulin, leptin concentration and obesity in Taiwan aborigines.
Four polymorphisms were compared in 324 obese (body mass index (BMI) > or =30 kg/m(2)) and overweight (30>BMI > or =25 kg/m(2)) subjects, and 114 normal weight subjects (BMI <25 kg/m(2)) in an aboriginal community of southern Taiwan. Anthropometric characteristics and fasting levels of insulin, leptin, triglycerides and cholesterol were measured.
Before and after adjusting for age distribution, only the Val55 allele in exon 4 of the UCP2 gene increased the risk of overweight and obesity (adjusted odds ratio (OR)=2.02, P=0.004) in comparison with Ala55. UCP2 V55V is also associated with higher fasting insulin levels than A55V (P=0.01) and A55A (P=0.04) in the obese/overweight group. Using the COCAPHASE program of the UNPHASED software, haplotype analysis of three single nucleotide polymorphisms (A55V-G866A-C-55T) revealed that A-G-C (73% in obese subjects and 77% in controls) was the most common haplotype and that the haplotype V-A-T (13% in obese subjects and 5% in controls) was significantly increased in obese and overweight subjects (BMI > or =25 kg/m(2)) (OR=2.62, P<0.001).
UCP2 A55V variant might predispose to obesity and Val55 allele to confer population-attributable risk for 9.5% of obese disorders and increase insulin concentrations. The V-A-T haplotype within UCP2-UCP3 gene cluster is also significantly associated with obesity in Paiwan aborigines.
International Journal of Obesity 11/2007; 31(11):1746-52. · 5.22 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In 2003 esophageal cancer was the sixth leading cause of death among men in Taiwan, but it is the fastest increasing (70%) alimentary tract cancer. The aim of this study was to investigate the impact of different habits of betel nut chewing on esophageal squamous cell carcinoma (SCC) and its interaction with cigarette use and alcohol consumption.
All 165 cases were pathologically proven esophageal SCC patients (all male, mean age = 56.0, range = 35-92 years) diagnosed by biopsy during gastroendoscopic examinations. The control group comprised 255 subjects (all male, mean age = 54.8, range = 40-92 years) selected from patients who had visited the Otolaryngology Outpatient or Inpatient Department of KMUH owing to a benign lesion over this field. All were interviewed to collect demographic and substance use information by a trained interviewer using a standardized questionnaire.
Smoking (aOR = 5.4, 95% CI = 2.4-12.9, PAR = 72%), alcoholic beverage drinking (aOR = 17.6, 95% CI = 9.3-35.2, PAR = 76%) and low education level are independent risk factors for esophageal cancer. Although betel nut chewers only had a borderline significant higher risk than nonchewers (aOR = 1.7; 95% CI = 0.8-3.1), those who chewed with a piece of betel inflorescence (aOR = 4.2, 95% CI = 1.4-16.0) and swallow betel-quid juice (aOR = 3.3, 95% CI = 1.3-9.3) had a significant higher risk. Significant dose-response effects were found in daily quantity of drinking and smoking. There is a synergistic effect of these three substances on the development of esophageal cancer.
Betel nut chewing plays a relevant role in the development of esophageal SCC but adds to the carcinogenetic effect of smoking and alcohol drinking. Direct mucosal contact of betel juice may contribute to its carcinogenesis.
European Journal of Clinical Investigation 05/2006; 36(4):236-41. · 3.37 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The mortality rates of cerebral and cardiovascular diseases are higher for aborigines than non-aborigines in Taiwan. Hypertriglyceridaemia and hypercholestolaemia are risk factors for cardiovascular diseases.
To investigate the prevalence of dyslipidaemia and its associated risk factors in aborigine (Atayal, Paiwan and Bunun tribes) and non-aborigine (Fukein and Hakka Chinese) children and adolescents in Taiwan.
This was a cross-sectional study.
In total, 718 males and 721 females, below 20 years of age, were recruited. Our study defined dyslipidaemia as serum triglyceride and cholesterol levels greater than 200 and 240 mg/dl, respectively.
The serum triglyceride level and the prevalence of hypertriglyceridaemia were similar in both aborigines and non-aborigines and both sexes, but the Bunun and Paiwan tribes had the highest prevalence of hypertriglyceridaemia in males (11.8-29.4%) and females (10.9-22.8%) compared with other aboriginal tribes (5.1-10.8% for males and 7.8-9.2% for females). Serum cholesterol concentrations and the prevalence of hypercholesterolaemia were lower in the aborigines than non-aborigines for both sexes (P<0.05), with the Atayal tribe having the lowest prevalence in males (1.1%) and females (2.1%) compared with other aboriginal tribes (2.4-4.5% for males and 5.7-8.0% for females). Using multivariate-adjusted logistic regression modelling, hypertriglyceridaemia was significantly associated with the Bunun tribe (odds ratio (OR)=3.2, 95% confidence intervals (CI) 1.6-6.1), hyperuricaemia (OR=1.8, 95% CI 1.2-2.6), hypercholesterolaemia (OR=3.3, 95% CI 1.7-6.4) and alcohol use (OR=2.8, 95% CI 1.2-6.6). Hypercholesterolaemia, after controlling for age and sex, was significantly associated with the Atayal tribe (OR=0.2, 95% CI 0.1-0.5), hypertriglyceridaemia (OR=3.5, 95% CI 1.8-6.7) and hyperuricaemia (OR=3.2, 95% CI=1.7-6.0).
For the young people of Taiwan, hypertriglyceridaemia is associated with hyperuricaemia, hypercholesterolaemia and alcohol use, and hypercholesterolaemia is associated with hypertriglyceridaemia and hyperuricaemia. Compared with non-aborigines, the young aborigines of some tribes have a higher prevalence of hypertriglyceridaemia and a lower serum cholesterol level.
Public Health 06/2005; 119(6):489-97. · 1.35 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The prevalence of allergic rhinitis, a common respiratory disorder, may be rapidly increasing. Epidemiological studies, however, indicate little about its association with climatic factors and air pollution. The relationship between traffic-related air pollutants and allergic rhinitis in middle-school students was therefore investigated. In a nationwide survey of middle-school students in Taiwan conducted in 1995/1996, the lifetime prevalence of physician-diagnosed allergic rhinitis and typical symptoms of allergic rhinitis were compared with air-monitoring station data on temperature, relative humidity, sulphur dioxide (SO2), nitrogen oxides (NOx), ozone (O3), carbon monoxide (CO) and particulate matter with a 50% cut-off aerodynamic diameter of 10 microm (PM10). A total of 331,686 nonsmoking children attended schools located within 2 km of 55 stations. Mean (range) annual exposures were: CO 853 (381-1,610) parts per billion (ppb), NOx 35.1 (10.2-72.4) ppb, SO2 7.57 (0.88-21.2) ppb, PM10 69.2 (40.1-116.2) microg x m(-3), O3 21.3 (12.4-34.1) ppb, temperature 22.9 (19.6-25.1) degrees C, and relative humidity 76.2 (64.8-86.2)%. The prevalence of physician-diagnosed allergic rhinitis was 28.6 and 19.5% in males and females, respectively, with prevalence of questionnaire-determined allergic rhinitis 42.4 and 34.0%. After adjustment for age, parental education and history of atopic eczema, physician-diagnosed allergic rhinitis was found to be associated with higher nonsummer (September-May) warmth and traffic-related air pollutants, including CO, NOx and O3. Questionnaire-determined allergic rhinitis correlated only with traffic-related air pollutants. Nonsummer warmth and traffic-related air pollution, probably mediated through exposure to common allergens such as dust mites, are possible risk factors for allergic rhinitis in middle-school-aged children.
European Respiratory Journal 07/2003; 21(6):964-70. · 6.36 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The prevalence of asthma in school children in Taiwan is increasing. This study used mass screening among middle school children in Taiwan to determine the prevalence of asthma and related factors.
Data were collected from parents using a self-reported questionnaire and from children using the International Study of Asthma and Allergies in Childhood (ISAAC) video questionnaire. Six study teams conducted the survey nationwide in 1995-1996, with the assistance of middle school nurses and teachers.
Among the 1,018,031 students at 795 middle schools who returned questionnaires, 8.5% had a history of asthma (ranging in prevalence from 4.2% to 13% in 25 areas). The prevalence of asthma was higher in boys than in girls (10.0% vs 7%) and was highest in more urbanized areas (11.2%), followed by moderately urbanized areas (7.4%) and less urbanized and rural areas (6.5%). Controlling for age, family smoking, family incense burning, and parental education level, multivariate logistic regression models indicated that children living in an area with heavy air pollution were more likely to have asthma than those in an area with no or light pollution (odds ratio, OR = 2.01 and 95% confidence interval, CI = 1.94-2.09 based on parental ranking of pollution level, or OR = 1.30 and 95% CI = 1.18-1.42 based on pollution level reported by the Environmental Protection Administration).
Adolescent asthma in Taiwan is most prevalent in the most urbanized areas and decreases in prevalence in less urbanized areas. This study also found that higher parental education level and higher area air pollution were associated with higher adolescent asthma prevalence.
Journal of the Formosan Medical Association 11/2001; 100(10):649-55. · 1.00 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Although family studies have established that asthma has a hereditary basis, little evidence has been presented about the family risk of simple asthma (AS or nonatopic asthma) and asthma with other atopic diseases (AWAD or atopic asthma) after adjusting for potential risk factors. In this study, data were collected on demographic variables and a wide range of known risk factors for asthma. Study participants were asthmatic adolescents and controls, and their relatives. The role of a familial history of asthma and atopic diseases in predicting asthma risk among asthmatic adolescents and their relatives was evaluated in a population-based family study conducted in southern Taiwan. Asthma risk factor data were collected through telephone interviews with students' parents for 207 asthmatic adolescents 11-16 years of age, their 1600 relatives, and 207 nonasthmatic adolescents in the control group and their 1638 relatives. The results show (after adjusting potential confounders) that a family history of asthma is highly associated with asthma in adolescents. Having two or more family members with asthma was associated with a 3.4-fold (95% confidence interval [CI] = 1.0-12.0) increased risk of asthma among adolescents. Logistic regression was used to assess the effects of having an asthmatic relative and the effect of atopic diseases among relatives of cases. Having a family history of asthma and other atopic conditions, such as rhinitis and atopic dermatitis (adjusted odds ratio [AOR] = 3.64, 95% CI = 2.29-5.74 and AOR = 1.94, 95% CI = 1.53-2.46, respectively), was found to be a significant predictor of asthma in children. Along with a history of allergic rhinitis or atopic dermatitis, familial risks of asthma occurring in adolescents with and without other atopic diseases will be analyzed separately. A critical finding was the significant difference in a risk of asthma and atopic diseases among the relatives of asthma cases with atopic diseases and controls. However, for relatives of asthma cases without atopic diseases compared to control probands, AORs were highly significant for family history of asthma, but not for the family history of atopic diseases. These findings suggest that both forms of asthma may be hereditary, but there are differences in their modes of inheritance. Atopic status itself did not predispose a child to AS. A concomitant inheritance of a predisposition to asthma and atopic condition for AWAD cases was suggested.
Journal of Asthma 10/2001; 38(6):485-94. · 1.85 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The difference in histologic patterns of lung cancer between men and women in Taiwan may be associated with the heterogeneity in causal factors of lung cancer between the sexes. A sex- and age-matched case-control study was designed to investigate such a relationship.
Cases consisted of 236 male and 291 female incident cases with newly diagnosed and histologically confirmed primary carcinoma of the lung, and were compared to one or two individually matched controls.
Cigarette smoking, occupations, and previous tuberculosis history were found to independently correlate with an elevated risk of squamous/small cell carcinoma and adenocarcinoma for male patients. However, there was little difference in the effect of these risk factors except smoking. The use of fume extractors in the kitchen, and the habit of waiting to fry after the fumes were emitted, separately explained the majority of the attributable fraction of female squamous/small cell carcinoma (28.2%) and adenocarcinoma (47.7%). With the exception of a kitchen with fume extractors and a clinical history of tuberculosis, the environmental causal factors of lung cancer were heterogeneous between these two histologic cell groups.
Our results suggested that the causal factors of lung cancer might be specific for the type of tumor concerned. The gender-specific risk factors of lung cancer could partly explain the difference in cell-type distribution between men and women.
Cancer Causes and Control 06/2001; 12(4):289-300. · 3.20 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Early studies that found significant linkage between markers on 5q and asthma and IgE have not been reproduced. In an attempt to improve the power of these studies we performed a variance components linkage analysis and transmission-disequilibrium tests (TDT) with haplotypes using markers on 5q, using the Southampton and Perth data sets supplied by GAW. The linkage analysis with covariates revealed a maximum lod of 1.57 in the Perth families. The addition of age and RAST significantly improved the fit of the null models but did not improve the lod scores. The TDT tests showed a marginally significant association with D5S393 and D5S399 and with three markers together (IL9, IL4, D5S393). We conclude that further studies are needed to delineate the environmental contribution to this disease so that the genetic factors can be more easily identified. In addition, haplotype analysis may help to identify specific genetic effects.
[Show abstract][Hide abstract] ABSTRACT: In the present study, we examined the factors affecting Aboriginal children's visits to a medical practitioner and compared them with non-Aboriginal children.
We selected five Aboriginal communities and four neighbouring non-Aboriginal communities, and conducted a door-to-door survey, covering all children born after 1983. Of an initial sample of 1013 children, 896 (response rate 89.92% for non-Aboriginal children and 85.87% for Aboriginal children) completed the questionnaire for analysis.
In all, 896 children of non-mixed lineage with an age range of 0-12 years were collected into the study, including 316 Aborigines and 580 non-Aborigines. A higher percentage of non-Aboriginal children had more national health insurance coverage than Aboriginal children. The ratio of parents using the services of an out of community medical practitioner when their children were sick was higher for Aboriginal parents than for non-Aborigines. Medical injection frequency was higher in Aboriginal children. Linear regression was used to examine the factors affecting the frequency of physician utilization in the preceding month.
A lower national health insurance coverage rate, and a higher rate of intramuscular injections for Aboriginal children plus difficulties in access to medical resources due to travel time and travel distance are still major problems for the Aborigines.
Family Practice 11/2000; 17(5):414-21. · 1.83 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Although asthma has a significant heritable component, the mode of inheritance remains controversial because of the complexity of the disease and the influence of environmental factors. Segregation analysis for asthma are performed with and without a history of atopic diseases (dermatitis and rhinitis) after adjusting for environmental factors. To investigate whether asthma may be inherited through a major gene with two alleles, the REGD program of the Statistical Analysis for Genetic Epidemiology (SAGE) package was conducted in 1,990 individuals from 227 families with at least one asthmatic child in a cross-sectional study of respiratory diseases in Southern Taiwan. Other covariates adjusted for included age, sex, current smoking, and environmental tobacco smoking. The hypothesis of Mendelian model and no parent-offspring transmission was rejected. However, when the variables of atopic disease and environmental factors were included in the model as covariates, the models for a two-allele gene with a recessive or codominant inheritance could not be rejected, and Akaike's Information Criterion was smaller (1,377. 13) for the recessive model than all of the other models tested, assuming a major gene with a population frequency of 0.56 +/- 0.04. However, Mendelian model without family effect was rejected. In conclusion, a history of asthma in parents is a strong risk factor for asthma in offspring. Under the assumptions of the applied segregation, at least one major gene exists that could be a gene involved also in allergy. However, the data suggest that a single locus gene explains a portion of asthma that is related to the history of atopic diseases. In addition, a polygenic/multifactorial (genetic and environmental factors) influence with a recessive component inheritance may be involved in the pathogenesis of asthma.
American Journal of Medical Genetics 09/2000; 93(5):373-80.
[Show abstract][Hide abstract] ABSTRACT: For a female population with a high lung cancer mortality rate, such as Taiwanese women, who smoke relatively rarely, but live in an environment with high male smoking prevalence, the risk and population burden of lung cancer due to environmental tobacco smoke (ETS) are relatively important.
An age-matched case-control study was designed to investigate the effects of cumulative environmental exposure to tobacco smoke during childhood and adult life on lung cancer risk among non-smoking women in Taiwan. Information on passive smoking from all possible sources and life periods were obtained from interviews with 268 and 445 lifetime non-smoking cases and controls. Conditional logistic regression and synergism 'S' index were applied to the data to assess the independent and joint effects of passive smoking in different life stages while controlling for possible confounding variables.
Risks of contracting lung cancer among women near-distantly exposed to the highest level of ETS in childhood (>20 smoker-years) and in adult life (>40 smoker-years) were 1.8-fold (95% CI: 1.2-2.9) and 2.2-fold (95% CI: 1.4-3.7) higher than that among women being never exposed to ETS, and the two variables accounted for about 37% of tumours in this non-smoking female population. Children were found to be more susceptible to ETS than adults and such early exposure was found to modify the effect of subsequent tobacco smoke exposure in adult life based on an additive interaction model.
Environmental tobacco smoke exposure occurring in childhood potentiates the effect of high doses of exposure in adult life in determining the development of lung cancer. Smoking prohibition would be expected to protect about 37% of non-smoking Taiwanese women against lung cancer.
International Journal of Epidemiology 05/2000; 29(2):224-31. · 6.98 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Cigarette smoking cannot fully explain the epidemiologic characteristics of lung cancer in Taiwanese women, who smoke rarely but have lung cancer relatively often. In a previous study, the authors suspected that exposure to fumes from cooking oils was an important risk factor for lung cancer in Taiwanese women nonsmokers in the Republic of China. In a new case-control study conducted in 1993-1996, they further explored the association of oil fumes with lung cancer in women. Two sets of controls were used concurrently. The subjects were 131 nonsmoking incident cases with newly diagnosed and histologically confirmed primary carcinoma of the lung, 252 hospital controls hospitalized for causes unrelated to diseases of smoking, and 262 community controls; all controls were women nonsmokers matched by age and date of interview. Details on cooking conditions and habits were collected, in addition to other epidemiologic data. Lung cancer risk increased with the number of meals per day to about threefold for women who cooked these meals each day. The risk was also greater if women usually waited until fumes were emitted from the cooking oil before they began cooking (adjusted odds ratios = 2.0-2.6) and if they did not use a fume extractor (adjusted odds ratios = 3.2-12.2). These results suggest that a proportion of lung cancer may be attributable to the habit of waiting until the cooking oil has been heated to a high temperature before cooking the food.
American Journal of Epidemiology 02/2000; 151(2):140-7. · 4.78 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This study compared the prevalence of asthma with climate and air pollutant data to determine the relationship between asthma prevalence and these factors. We conducted a nationwide survey of respiratory illness and symptoms in middle-school students in Taiwan. Lifetime prevalences of physician-diagnosed asthma and of typical symptoms of asthma were compared to air monitoring station data for temperature, relative humidity, sulfur dioxide, nitrogen oxides, ozone, carbon monoxide, and particulate matter with aerodynamic diameter [less than/equal to] 10 microm (PM(10)). A total of 331,686 nonsmoking children attended schools located within 2 km of 55 stations. Asthma prevalence rates adjusted for age, history of atopic eczema, and parental education were associated with nonsummer (June-August) temperature, winter (January-March) humidity, and traffic-related air pollution, especially carbon monoxide and nitrogen oxides, for both girls and boys. Nonsummer temperature, winter humidity, and traffic-related air pollution, especially carbon monoxide and nitrogen oxides, were positively associated with the prevalence of asthma in middle-school students in Taiwan.
Environmental Health Perspectives 01/2000; 107(12):1001-6. · 7.26 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: It is known that substance use is associated with increased risk of adverse pregnancy, outcomes. The aims of this study were to estimate the prevalence of alcohol, cigarette, betel quid and drug use during pregnancy and to assess the risk of adverse effects of betel quid chewing on pregnancy outcomes in aboriginal women in southern Taiwan. The study population included 62 women with adverse pregnancy outcomes and 124 age-matched women. Subjects were interviewed at their homes by trained interviewers using a structure questionnaire. Prevalences of various substance use in aborigines with adverse pregnancy outcomes were estimated as follows: alcohol, 43.6%; smoking, 14.5%; betel quid chewing, 43.6% and over-the-counter drug use, 8.1%; whereas in the comparison group it was alcohol, 38.7%; smoking, 8.1%; betel quid chewing, 28.2% and none used drugs. Univariate analysis revealed that adverse pregnancy outcomes were associated with maternal betel quid chewing, maternal illness during pregnancy, and the number of pregnancies (gravidity) experienced. After adjusting for maternal illness and number of previous pregnancies covariates, the prevalence of adverse pregnancy outcome was computed to be 2.8-fold higher among betel quid chewing women as compared to non-chewers (AOR=2.8, 95% CI=1.2-6.8). Among the aboriginal women, prenatal care is essential not only for routine care, but also to focus health education on the harmful effects of substance use, especially betel quid use during pregnancy.
Public Health 08/1999; 113(4):189-92. · 1.35 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: According to earlier studies, fumes from cooking oils were found to be genotoxic in several short-term tests such as the Ames test, sister chromatid exchange, and SOS chromotest. Fume samples from six different commercial cooking oils (safflower, olive, coconut, mustard, vegetable, and corn) frequently used in Taiwan were collected. Polycyclic aromatic hydrocarbons (PAHs) were extracted from the air samples and identified by high-performance liquid chromatography and confirmed by gas chromatography/mass spectrometry. Extracts of fumes from safflower oil, vegetable oil, and corn oil contained benzo[a]pyrene (BaP), dibenz[a,h]anthracene (DBahA), benzo[b]fluoranthene (BbFA), and benzo[a]anthracene (BaA). Concentrations of BaP, DbahA, BbFA, and BaA were 2.1, 2.8, 1.8, and 2.5 microg/m3 in fumes from safflower oil; 2.7, 3.2, 2.6, and 2.1 microg/m3 in vegetable oil; and 2.6, 2.4, 2.0, and 1.9 microg/m3 in corn oil, respectively. The authors constructed models to study the efficacy of table-edged fume extractors used commonly by Taiwanese restaurants. Concentrations of BaP were significantly decreased when the fume extractor was working (P<0.05) and the average reduction in percentage was 75%. The other identified PAHs were undetected. These results indicated that exposure to cooking oil fumes could possibly increase exposure to PAHs, which may be linked to an increased risk of lung cancer. The potential carcinogenic exposure could be reduced by placing table-edged fume extractors near cooking pots.
Environmental Research 07/1999; 81(1):18-22. · 3.24 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Epidemiologic investigations of lung cancer among Taiwanese nonsmoking women have found that exposure to fumes from cooking oils may be an important risk factor. Fume samples from three different commercial cooking oils (lard, soybean, and peanut oils) often used in Taiwan for preparing Chinese meals were collected for genotoxicity analysis in SOS chromotest and sister chromatid exchange (SCE) assays. The induction factors of the SOS chromotest in Escherichia coli PQ 37 were dependent on the concentrations of lard and soybean cooking oil extracts without S9 mix. In addition, when CHO-K1 cells were exposed to condensates of cooking oil fumes for 12 h, SCEs showed a dose-related increase in extracts of lard and soybean oil fumes. This result provides experimental evidence and is in accordance with the findings of epidemiologic studies that women exposed to the emitted fumes of cooking oils are at an increase risk of contracting lung cancer.
Environmental Research 03/1999; 80(2 Pt 1):122-6. · 3.24 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: According to toxicological studies, there are several unidentified mutagens derived from cooking oil fumes appearing in kitchens of Chinese homes where women daily prepare food. Data are limited to an analysis of aromatic amines from cooking oil fumes, which are known to be carcinogenic for bladder cancer. Fume samples from three different commercial cooking oils frequently used in Taiwan were collected and analysed for mutagenicity in the Salmonella/microsome assay. Aromatic amines were extracted from the samples and identified by HPLC and confirmed by gas chromatography/mass spectrometry (GC/MS). Extracts from three cooking oil fumes were found to be mutagenic in the presence of S-9 mix. All samples contained 2-naphthylamine (2-NA) and 4-aminobiphenyl (4-ABP). Concentrations of 2-NA and 4-ABP were 31.5 and 35.7 microg/m3 in fumes from sunflower oil, 31.9 and 26.4 mg/m3 in vegetable oil, and 48.3 and 23.3 microg/m3 in refined-lard oil, respectively. Mutagenicities of the three cooking oil condensates were significantly reduced (P<0.05) by adding the antioxidant catechin (CAT) into the oils before heating. Significant difference existed between the amounts of aromatic amines with and without adding CAT (P<0.05). These results indicate that exposure to cooking oil fumes in Taiwan might be an important but controllable risk factor in the aetiology of bladder cancer.
Food and Chemical Toxicology 02/1999; 37(2-3):125-34. · 3.01 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Blackfoot disease was prevalent in a limited area on the southwest coast of Taiwan, where artesian well water containing arsenic (median = 0.78 ppm arsenic) had been used for many years. Previous studies of arsenic exposure in the blackfoot disease endemic area have been focused on malignant tumors. We, therefore, conducted this study to analyze mortality of all death causes in blackfoot disease endemic areas and to determine other neglected cancers or noncancer diseases related to artesian well water containing high levels of arsenic. We calculated standardized mortality ratios for cancer and noncancer diseases, by sex, during the period from 1971 to 1994 and compared them to the local reference group (i.e, Chiayi-Tainan County) and the national reference group (i.e., Taiwan population). The results revealed marked standardized mortality ratio differences for the 2 reference groups. Greater mortality was found for males and females with bladder, kidney, skin, lung, nasal-cavity, bone, liver, larynx, colon, and stomach cancers, as well as lymphoma than in the local reference population. With respect to noncancer diseases, we found greater mortality for males and females who had vascular disease, ischemic heart disease, diabetes mellitus, and bronchitis than in the local reference group. Mortalities for other diseases--including rectal cancer, cerebrovascular disease, and other diseases--were higher among cases than the local reference group. Our results indicated that the hazardous effect of arsenic is systemic. Diseases related to arsenic exposure included those reported previously by other investigators, as well as diseases reported in the present study.
Archives of Environmental Health An International Journal 01/1999; 54(3):186-93.
[Show abstract][Hide abstract] ABSTRACT: Blackfoot disease is an endemic peripheral vascular disease found among people in a limited area on the southwest coast of Taiwan, where artesian well water has a high concentration of arsenic and was used since the turn of this century. This is an important public health problem and was noted by the authorities, who began improving the water supply in such communities in 1956. This enabled us to test the relationship between arsenic and malignant tumors using a specific exposed community. Study subjects were divided into four groups according to age (under or over 40 yr) and gender. Two methods were used for the estimation of the age-adjusted mortality rate ratios. First using the first time interval (1971-1973) as the standard, the mortality rate ratio for all malignant tumors was estimated from this interval through to the last interval (1992-1994) using Poisson regression. Cancers that were found to be related to arsenic in previous reports, such as liver, lung, bladder, kidney, and skin cancers, were examined and other malignant tumors except these cancers were also assessed. The same calculations were performed for all of Chiayi and Tainan counties, excluding the study areas, which were used as the local reference, and for the general population of Taiwan, which was used as a national reference group. Second, mortality rate ratios for the study area were compared to the local and national reference for the same time intervals for each disease category. From our results, significantly declining trends for mortality rate ratios of all malignant tumors with 1971-1973 as the standard were found for the study areas, especially in females. A decrease of mortality rate ratios from malignant cancers, compared to the local or national references, was found in those aged over 40 yr for both sexes. The decreases are mainly due to a fall in internal and skin cancer mortality rates. In conclusion, our results suggest that the improvement of drinking water supply to eliminate arsenic exposure from artesian well water decreased the mortality incidence of arsenic-related cancers in blackfoot disease endemic communities.
Journal of Toxicology and Environmental Health Part A 12/1998; 55(6):389-404. · 1.73 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Deleterious health sequelae caused by licit and illicit substance use is a serious problem in our society. Adolescent students and particularly those who are prone to substance use are of special concern in the prevention of drug abuse. The purpose of this study was to investigate the prevalence of alcohol consumption, tobacco smoking and illicit drug use and to identify the risk factors related to these habits among adolescent students. A total of 1358 adolescent students aged 16-18 y old were recruited into this study via stratified random sampling from a vocational school in Kaohsiung city. Students were asked to complete a structured questionnaire anonymously and a 96.7% response rate was achieved. Prevalence of substances use was estimated as follows: alcohol drinking, 70.7% (boys 75.1%, girls 51.4%); tobacco smoking, 56% (boys 61.8%, girls 30.2%); illicit drug use 6.4% (boys 6.6%, girls 5.6%). Significant risk factors that emerged as common correlates with substances use were behaviour problems, non-negative attitude toward parent's substance use, and peer influence. A dose-response relationship was found between the prevalence of drinking, smoking, illicit drug use and the number of risk factors adolescents were exposed to. Prevention of adolescent substance abuse should be attempted and risk factors should be reduced. An educational approach is essential not only to gain/impart knowledge of substance abuse, but also to develop an effective program for health and social development.
Public Health 10/1998; 112(5):347-52. · 1.35 Impact Factor