Rectal cancer mortality and total hardness levels in Taiwan's drinking water.

The possible association between the risk of rectal cancer and hardness levels in drinking water from municipal supplies was investigated in a matched case-control study in Taiwan. All eligible rectal cancer deaths (986 cases) of Taiwan residents from 1990 through 1994 were compared with deaths from other causes (986 controls), and the hardness levels of the drinking water used by these residents were determined. Data on water hardness throughout Taiwan were collected from Taiwan Water Supply Corporation (TWSC). The control group consisted of people who died from other causes and the controls were pair matched to the cases by sex, year of birth, and year of death. The results show a significant negative relationship between drinking water hardness and rectal cancer mortality. Odds ratio and 95% confidence intervals were 1.24 (1.01-1. 55) and 1.38 (1.10-1.73), respectively, for exposure to moderately hard water and soft water compared with the use of hard water. Trend analyses showed an increasing odds ratio for rectal cancer with decreasing levels of hardness in drinking water. This is an important finding for the Taiwan water industry and human health.     

Colon Cancer Mortality and Total Hardness Levels in Taiwan's Drinking Water

The possible association between the risk of colon cancer and hardness levels in drinking water from municipal supplies was investigated in a matched case-control study in Taiwan. All eligible colon cancer deaths (1,714 cases) of Taiwan residents from 1989 through 1993 were compared with deaths from other causes (1,714 controls) and the hardness levels of the drinking water used by these residents were determined. Data on water hardness throughout Taiwan have been collected from Taiwan Water Supply Corporation (TWSC). The control group consisted of people who died from other causes and the controls were pair matched to the cases by sex, year of birth, and year of death. The results show a significant negative relationship between drinking water hardness and colon cancer mortality. Odds ratio and 95% confidence intervals were 1.22 (1.04–1.43) and 1.46 (1.22–1.75), respectively, for exposure to moderately hard water and soft water compared with the use of hard water. Trend analyses showed an increasing odds ratio for colon cancer with decreasing levels of hardness in drinking water. This is an important finding for the Taiwan water industry and human health. Received: 8 July 1997/Accepted: 29 November 1997     

Gastric Cancer Mortality and Drinking Water Qualities in Taiwan

The possible association between the risk of gastric cancer and nitrate and hardness in drinking water from municipal supplies was investigated in a matched case-control study in Taiwan. Data on gastric cancer deaths among eligible residents in Taiwan from 1987 through 1991 (6,766 cases) were obtained from the Bureau of Vital Statistics of the Taiwan Provincial Department of Health. Controls were deaths from other causes (6,766 controls) and were matched individually to the cases by sex, year of birth, and year of death. Data on nitrate–nitrogen (NO₃–N) and hardness levels in drinking water throughout Taiwan were collected from the Taiwan Water Supply Corporation (TWSC). The municipality of residence for cases and controls was assumed to be the source of the subject's nitrate and hardness exposure via drinking water. There was no difference in gastric cancer rates between the groups with different levels of nitrate. The odds ratios (95% confidence interval) for death from gastric cancer was 0.95 (0.87–1.03) for the group with water nitrate levels between 0.23 and 0.44 mg/L, and 1.02 (0.93–1.11) for the group with nitrate levels greater than 0.45 mg/L. However, the results show a significant negative relationship between drinking water hardness and gastric cancer mortality. Odds ratios were 1.16 (1.07–1.26) and 1.65 (1.52–1.79), respectively, for exposure to moderately hard water and soft water compared with the use of hard water. This is an important finding for the Taiwan water industry and human health risk. Received: 27 November 1996/Accepted: 16 April 1997     

Calcium and magnesium in drinking water and risk of death from acute myocardial infarction in Taiwan

Many studies have examined the association between cardiovascular disease mortality and water hardness. However, the results have not been consistent. This report examines whether calcium and magnesium in drinking water are protective against acute myocardial infarction (AMI). All eligible AMI deaths (10,094 cases) of Taiwan residents from 1994 to 2003 were compared with deaths from other causes (10,094 controls), and the levels of calcium and magnesium in drinking water of these residents were determined. Data on calcium and magnesium levels in drinking water throughout Taiwan have been obtained from the Taiwan Water Supply Corporation. The control group consisted of people who died from other causes and the controls were pair matched to the cases by sex, year of birth, and year of death. The adjusted odd ratios (95% confidence interval) were 0.79 (0.73-0.86) for the group with water calcium levels between 25.1 and 42.4 mg/L and 0.71 (0.65-0.77) for the group with calcium levels of 42.6 mg/L or more. After adjustment for calcium levels in drinking water, there was no difference between the groups with different levels of magnesium. The results of the present study show that there is a significant protective effect of calcium intake from drinking water on the risk of death from AMI.     

Does calcium in drinking water modify the association between nitrate in drinking water and risk of death from colon cancer?

The objective of this study was to explore whether calcium (Ca) levels in drinking water modified the effects of nitrate on colon cancer risk. A matched case–control study was used to investigate the relationship between the risk of death from colon cancer and exposure to nitrate in drinking water in Taiwan. All colon cancer deaths of Taiwan residents from 2003 through 2007 were obtained from the Bureau of Vital Statistics of the Taiwan Provincial Department of Health. Controls were deaths from other causes and were pair-matched to the cases by gender, year of birth and year of death. Information on the levels of nitrate-nitrogen (NO₃-N) and Ca in drinking water have been collected from Taiwan Water Supply Corporation (TWSC). The municipality of residence for cases and controls was assumed to be the source of the subject's NO₃-N and Ca exposure via drinking water. We observed evidence of an interaction between drinking water NO₃-N and Ca intake via drinking water. This is the first study to report effect modification by Ca intake from drinking water on the association between NO₃-N exposure and risk of colon cancer mortality.     

Effect modification of the association between trihalomethanes and pancreatic cancer by drinking water hardness: Evidence from an ecological study

The objective of this study was to examine the relationship between total trihalomethanes (TTHM) levels in public water supplies and risk of pancreatic cancer and to determine whether calcium (Ca) and magnesium (Mg) levels in drinking water modify the effects of TTHM on risk to develop pancreatic cancer. A matched case-control study was used to investigate the relationship between the risk of death attributed to pancreatic cancer and exposure to TTHM in drinking water in 53 municipalities in Taiwan. All pancreatic cancer deaths in the 53 municipalities from 1998 through 2007 were obtained from the Bureau of Vital Statistics of the Taiwan Provincial Department of Health. Controls were deaths from other causes and were pair matched to the cancer cases by gender, year of birth, and year of death. Each matched control was selected randomly from the set of possible controls for each cancer case. Data on TTHM levels in drinking water were collected from Taiwan Environmental Protection Administration. Information on the levels of Ca and Mg in drinking water was obtained from the Taiwan Water Supply Corporation. The municipality of residence for cancer cases and controls was presumed to be the source of the subject's TTHM, Ca, and Mg exposure via drinking water. Relative to individuals whose TTHM exposure level<4.9 ppb, the adjusted OR (95% CI) for pancreatic cancer was 1.01 (0.85-1.21) for individuals who resided in municipalities served by drinking water with a TTHM exposure>4.9 ppb. There was no evidence of an interaction of drinking water TTHM levels with low Ca intake via drinking water. However, we observed evidence of an interaction between drinking water TTHM concentrations and Mg intake via drinking water. Our findings showed that the correlation between TTHM exposure and risk of pancreatic cancer is influenced by Mg in drinking water. Increased knowledge of the interaction between Mg and TTHM in reducing pancreatic cancer risk will aid in public policy making and standard setting.     

Gastric cancer mortality and nitrate levels in Wisconsin drinking water.

The association between nitrate levels in public and private sources of drinking water and gastric cancer mortality in Wisconsin was investigated in a case-control study. All gastric cancer deaths of Wisconsin residents from 1982 through 1985 were compared with deaths from other causes (controls), and nitrate levels in the home drinking water of these residents were determined. Nitrate measures for public sources were obtained from historic nitrate data from municipal sources that existed in 1970. Nitrate measures for private water sources were obtained by testing the wells individually at the existing residences. Controls were matched individually to gastric cancer cases with respect to sex, year of birth, year of death, Wisconsin birth, and Wisconsin residency at the time of death. Matched-pair analyses were performed on the paired data, and the following levels of nitrate-nitrogen exposure were used as indicators of exposure: 0.5, 2.5, 5.0, and 10.0 mg/l. Matched-pair analysis was also performed for which private water supply constituted exposure. Odds ratios and 95% confidence intervals were, respectively, 0.92 (0.75, 1.12); 0.97 (0.74, 1.35); 0.86 (0.69, 1.08); 1.50 (0.12, 18.25); and 1.09 (0.82, 1.47) for exposure to private well-water sources. These results did not indicate an increased risk of gastric cancer at any level.     

广东省揭阳市居民食管癌发病危险因素的 病例对照研究

目的：筛选广东省揭阳市食管癌的危险因素。方法：1999年在揭阳市人民医院接受治疗的214例食管癌和贲门癌病人纳入病例组,均经过病理学诊断,214名健康人为对照组,按病例组的性别,年龄和居住地（镇）的构成情况从人群中随机抽取。研究对象均在揭阳市居住20年以上,用统一的调查进行问卷调查。用非条件logistic回归进行多因素分析。结果：主要的危险因素是饮烫茶(OR:1．39－3．74）,吃饭快（OR：1．54－4．10）,吃硬饭（OR：1．32－4．27）,猪油（OR：3．57－42．03）和肉类（OR：1．36－5．05）;保护性因素是饮用自来水20年以上（OR：0．13－0．51）,未发现吸烟史、食管癌家族史与食管癌有关联。结论：本研究筛选出的因素普遍暴露于揭阳市民民中,多数因素与其它地区的同类研究一致,但猪油和肉类是本研究中提出的影响因素,有待于实验研究证实。     

河北省居民食管癌发病影响因素病例对照研究

目的了解河北省食管癌发病的影响因素,为预防食管癌发病提供科学依据。方法采用以医院为基础病例对照研究方法对2009年6月-2011年5月在河北医科大学附属第四医院住院的208例食管癌患者及同期住院的210例非消化道疾病患者进行问卷调查。结果不同组别居民生活习惯情况比较,病例组与对照组居民在吸烟、饮酒、食用烫食、食用硬食、饮食速度、饮食时间、吃霉变食物、吃水果、吃新鲜蔬菜、吃豆类及其制品、吃奶类及其制品等生活习惯间差异均有统计学意义(P<0.05);病例组抑郁、愤怒、愤怒向内和理智平均得分分别为(44.30±7.47)、(24.74±6.71)、(14.71±2.51)和(42.19±6.50)分,分别高于对照组的(40.47±6.87)、(22.58±5.00)、(13.82±2.25)和(40.83±3.58)分(P<0.01);社会支持平均得分为(16.24±3.20)分,低于对照组的(17.53±2.13)分(t=4.867,P=0.000);多因素Logistic回归分析结果表明,居住在城镇和农村、有食管癌家族史、家庭人际关系一般、吸烟量≥20支/d、食用硬食、吃霉变食物以及理智、愤怒和抑郁得分高是河北省居民食管癌发病的危险因素;经常吃豆类及其制品、饮用自来水和社会支持得分高是河北省居民食管癌发病的保护因素;有食管癌家族史、吸烟量≥20支/d、食用硬食、吃霉变食物以及理智和愤怒得分高是男性居民食管癌发病的危险因素;经常吃豆类及其制品和社会支持得分高是男性居民食管癌发病的保护因素;食用烫食、食用硬食、抑郁得分高是女性居民食管癌发病的危险因素;饮用自来水、经常吃水果和社会支持得分高是女性食管癌发病的保护因素。结论河北省食管癌的发生与环境、饮食、吸烟、食管癌家族史及C型行为等有关,男女的影响因素有别,应根据具体情况采取有针对性的预防措施。     

Mutagenic drinking water and risk of male esophageal cancer: a population-based case-control study.

Drinking mutagenic downstream water from the Huangpu River was hypothesized to have increased the risk for male esophageal cancer in Shanghai, China. The authors conducted a population-based case-control study of a total of 71 esophageal cancer deaths and 1,122 controls collected during a 5-year follow-up period, 1984-1988, from four male cohorts born before January 1, 1944, living in four communities consuming water with different mutagenicities in the Shanghai area. The controls represented a 1% random sample of the defined living cohorts selected at the end of each of the 5 years of follow-up. Logistic regression showed an odds ratio of 2.77 (95% confidence interval: 1.52, 5.03) for drinking mutagenic downstream water from the river versus drinking nonmutagenic upstream water after controlling for possible confounders including age, disease history (hepatitis, cirrhosis, schistosomiasis, digestive tract ulcer), hazardous occupational history, pesticide exposure, lifestyle factors (cigarette smoking, tea intake, and alcohol intake), dietary habits (intake of pickled vegetables, maize, peanuts, and cured meat), education, poverty, urban environment, and water chlorination.     

新疆哈萨克族食管癌危险因素病例对照研究

目的探讨新疆哈萨克族食管癌发病的危险因素。方法采用1∶2配比的病例对照研究方法,调查92例食管癌患者、184名正常对照。采用条件Logistic回归模型进行分析。结果单因素分析显示,职业为牧民、饮用手压机井水、河水、大量饮酒、喜辣食、食速快、不规律、有食管、胃病变史及食管癌家族史等因素与食管癌的发生有关;多因素Cox回归分析显示,饮用手压机井水或河水、有食管癌家族史、辛辣饮食及食速快为食管癌发生的主要危险因素,食用新鲜水果为保护因素。结论改善饮水条件,改变不良饮食生活习惯,经常食用新鲜蔬菜和水果,可减少哈萨克族食管癌发生的危险性。     

食管病变影响因素的多项式Logistic回归分析

目的探讨食管癌家族史、吸烟和饮酒与食管炎症、增生、早期癌间的关联。方法在食管癌高发社区40-69岁队列人群中，将内镜检查正常者作为对照组，炎症、增生、早期癌患者分别作为病例组，所有病例均经染色内镜和病理活检确诊。采用多项式Logistic回归模型，将OR作为评价关联强度的指标。结果确诊早期癌71例、增生266例、炎症144例，食管黏膜正常2818例。有食管癌家族史与食管早期癌、增生、炎症均呈显著性相关；其中一级血亲患食管癌在3组的OR值分别为2．6（95％CI=1．36～4．85）．2．1（95％CI=1．43～2．99），1．8（95％CI=1．13～3．03），但二级血亲患食管癌在3组的OR值差异均无统计学意义。有食管癌家族史尤其是一级血亲患有食管癌者吸烟或／和饮酒能显著增加食管癌的危险性。结论在食管癌高发区，有食管癌家族史者应戒烟酒，以预防食管良恶性疾病的发生。     

Female lung cancer and petrochemical air pollution in Taiwan.

To investigate the relationship between petrochemical air pollution and female lung cancer, we conducted a matched case-control study among women who had died in Taiwan from 1990 through 1994. Data about all eligible female lung cancer deaths were obtained from the Bureau of Vital Statistics of the Taiwan Provincial Department of Health. The control group included women who died from nonneoplasms and diseases that were not associated with respiratory problems. We pair-matched the controls to the cases by sex, year of birth, and year of death. Each matched control was selected randomly from the set of possible controls for each case. We used the proportion of a municipality's total population employed in the petrochemical manufacturing industry as an indicator of a resident's exposure to air emissions from the petrochemical manufacturing industry. The subjects were divided into tertiles according to the above indicator. Women who lived in the 2 groups of municipalities characterized by higher levels of petrochemical pollution had a statistically significant higher risk of developing lung cancer than the group that lived in municipalities with the lowest petrochemical air pollution levels (after controlling for possible confounders). The linear trend was also statistically significant (p < .05). The results of this study shed important light on the relationship between the Taiwan petrochemical industry and the resulting risk to human health.     

太行山食管癌高发区农村高危人群上消化道癌及癌前病变筛查结果及影响因素分析

目的 了解太行山食管癌高发区农村高危人群上消化道癌及癌前病变的检出情况,探讨其影响因素。方法 采用整群抽样的方法确定调查对象。 采用问卷调查、体格检查、内窥镜检查和病理学检查对调查对象进行上消化道癌及癌前病变的筛查。结果 共筛查出上消化道癌高危人群1 200名,根据内窥镜检查条件,共筛查高危人群865名,其中共检出阳性病例111例,总阳性病检出率12.8% 。多因素 logistic 回归分析结果表明,≥60岁（OR = 1.411,95%CI:1.1470～2.192）、腌制食品 (OR = 1.736,95% CI:1.149 ～ 2.625)、饮用水来源为井水（OR = 1.789,95%CI:1.119～2.861）或其他水源（OR = 2.143,95%CI:1.086～4.228）、幽门螺旋杆菌感染 （OR = 1.850,95%CI:1.219～2.8077）是上消化道癌及癌前病变发生的独立危险因素。结论 本地区上消化道癌及癌前病变的检出率仍然较高,年龄大、吃腌制食品、饮用水来源为井水、河水、雨水等,以及感染幽门螺旋杆菌是本地区农村居民上消化道癌及癌前病变发生的危险因素。     

Estimation of potential lifetime cancer risks for trihalomethanes from consuming chlorinated drinking water in Taiwan

Data on concentrations of trihalomethanes (THMs) in raw and chlorinated water collected from three water treatment plants in Taiwan and estimates of the lifetime cancer risk for THMs from drinking water, using age-adjusted factors and volatilization terms, are presented. Data on THM levels in drinking water were obtained from the annual reports of the Environmental Protection Administration (EPA) of Taiwan. The methodology for estimation of lifetime cancer risks was taken from the USEPA. Chloroform was the major species of THMs, especially in the water plant of south Taiwan. Chloroform contributed the majority of the lifetime cancer risks (range: 87.5-92.5%) of total risks from the three water supply areas. All lifetime cancer risks for CHCl(3), CHBrCl(2), CHBr2Cl, and CHBr3 from consuming tap water in the three water supply areas were higher than 10(-6). The sum of lifetime cancer risks for CHCl(3), CHBrCl(3), CHBr2Cl, and CHBr3 was highest (total risk for total THMs<1.94x10(-4)) for tap water from south Taiwan.     

山东省东平县食管癌危险因素交互作用研究

目的 探讨食管癌致病因子以及致病因子之间的交互作用。方法 对2004年1月1日—2005年12月31日山东省东平县472例新发食管癌患者和472名均衡性较好的对照者进行对比研究。在非条件Logistic回归分析的基础上,分析东平县食管癌各致病因子病因分值及食管癌家族史与其他各致病因子的交互作用。结果 人群病因分值由大到小依次为喜烫食（0.855）、喜食腌制品（0.758）、喜食干硬食物（0.683）、好生闷气（0.464）、饮用水污染（0.459）、食管癌家族史（0.343）、大量饮酒（0.108）。预防分值由大到小依次为大量饮酒（-0.121）、食管癌家族史（-0.520）、饮用水污染（-0.850）、好生闷气（-0.864）、喜食干硬事物（-2.160）、喜食腌制品（-3.133）、喜烫食（-5.907）。在食管癌家族史与其他某一危险因素同时存在并协同作用中,以食管癌家族史＋烫食、食管癌家族史＋喜食干硬食物最为显著,其交互作用指数均为0.86,均有统计学意义。结论 食管癌家族史与不良生活行为方式的交互作用在食管癌发生过程中尤为重要。     

Ecological analyses and case-control studies of gastric cancer and leukaemia in relation to DBCP in drinking water in Fresno County, California.

Through ecological analyses and case-control studies, the possible relation of gastric cancer and leukaemia to dibromochloropropane (DBCP) contamination of drinking water in Fresno County, California, has been examined. The ecological analyses examined the correlation between gastric cancer and leukaemia (including the lymphatic varieties), mortality rates, and DBCP concentrations in drinking water by census tract in Fresno County, 1960-83. No correlation was found between gastric cancer or leukaemia and DBCP. The gastric cancer case-control study consisted of 263 deaths from gastric cancer in the county, 1975 to mid-1984, and 1044 controls, using information on residential history and occupation of both cases and controls. Analyses were based on residence at death, as well as one and ten years before death. The case-control study did not find any relation between gastric cancer and DBCP in drinking water. Hispanics in the county were found to experience a relative risk of gastric cancer of 2.77, compared with non-Hispanics. A similar case-control study consisting of 259 cases of leukaemia and 1161 controls found no relation between all leukaemia or lymphatic leukaemia and DBCP in drinking water. Farm workers, however, do appear to have an increased risk of leukaemia.     

Ecological analyses and case-control studies of gastric cancer and leukaemia in relation to DBCP in drinking water in Fresno County, California

Through ecological analyses and case-control studies, the possible relation of gastric cancer and leukaemia to dibromochloropropane (DBCP) contamination of drinking water in Fresno County, California, has been examined. The ecological analyses examined the correlation between gastric cancer and leukaemia (including the lymphatic varieties), mortality rates, and DBCP concentrations in drinking water by census tract in Fresno County, 1960-83. No correlation was found between gastric cancer or leukaemia and DBCP. The gastric cancer case-control study consisted of 263 deaths from gastric cancer in the county, 1975 to mid-1984, and 1044 controls, using information on residential history and occupation of both cases and controls. Analyses were based on residence at death, as well as one and ten years before death. The case-control study did not find any relation between gastric cancer and DBCP in drinking water. Hispanics in the county were found to experience a relative risk of gastric cancer of 2.77, compared with non-Hispanics. A similar case-control study consisting of 259 cases of leukaemia and 1161 controls found no relation between all leukaemia or lymphatic leukaemia and DBCP in drinking water. Farm workers, however, do appear to have an increased risk of leukaemia.     

Drinking water hardness and chronic degenerative diseases. III. Tumors,urolithiasis, fetal malformations,deterioration of the cognitive function in the aged and atopic eczema

For several decades a causal relation has been hypothesised between drinking water hardness and cardiovascular and other chronic degenerative diseases in humans. Only recently some epidemiological studies also investigated the association between the concentration of the minerals responsible for the hardness of drinking water (calcium and magnesium) and other chronic diseases. Some case-control studies carried out in Taiwan using aggregated data showed a possible protective effect of water hardness toward the risk of dying from various neoplasms, though more research is needed on the issue, possibly based on individual data, to draw definitive conclusions. There is a substantial evidence that consumption of water with high levels of calcium does not increase, and maybe reduces the risk of developing urinary stones of the most common type in developed countries (calcium oxalate), on the contrary, there is no conclusive evidence on the relation between water hardness and foetal malformations, cognitive functions in old men, diabetes and eczema.     

饮用农田边水源水与消化道恶性肿瘤关系的病例对照研究

目的分析农田边饮用水源水是否为农村消化道恶性肿瘤高发的危险因素,为肿瘤防控提供依据。方法应用病例对照研究,以青田、龙泉和缙云3个县（市）2009—2011年报告确诊的180例消化道恶性肿瘤为病例组,按居住乡镇、年龄与性别1∶2配比360名健康人群为对照组,分析饮用农田边水源水对消化道恶性肿瘤致病的影响。结果 3个县（市）调查点的全部病例组饮用农田边水源的暴露比高于对照组（OR=4.005,95%CI为2.228~7.199）,青田县病例组饮用农田边水源水人群的消化道恶性肿瘤发病危险性是饮用非农田边水源水人群的5.375倍（95%CI为2.287~12.635）,而龙泉市和缙云县则未见统计学关联（P〉0.05）。胃癌组暴露农田边水源水比例高于对照组（OR=4.875,95%CI为2.007~11.839）,但肝癌、结直肠癌和食管癌病例组农田边水源水暴露比例与对照组差异均无统计学意义（P〉0.05）。青田县胃癌组病例暴露农田边水源水的比例是对照组的5.750倍（95%CI为1.683~19.649）,其他病种病例组与对照组的暴露比例差异无统计学意义（P〉0.05）。结论农田边饮用水源水可能是农村部分地区胃癌高发的危险因素之一。