Fish consumption habits and advisory awareness among Fox River anglers.

Eating PCB-contaminated fish caught from the Lower Fox River, northeast Wisconsin, has raised concern about the health risk to consumers, especially to children and unborn babies. The fish advisory published by the state of Wisconsin recommends which fish are safe to eat. However, there is reason to believe that many anglers, especially non-English speaking anglers, are not aware of the advisory and the possible health risks of eating contaminated fish. A face-to-face survey administered to 104 anglers fishing along the Fox River indicates that 17% of anglers eat some or all of the fish they catch and that 83% practice "catch and release." Almost all the anglers were not familiar with Wisconsin's fish advisory but had heard of the health risks from their local newspaper and TV. As a follow-up, a fish health advisory brochure specific to the Fox River was developed.

Low-cost household paint abatement to reduce children's blood lead levels.

The purpose was to examine the effectiveness of low-cost abatement on children's blood lead levels. Blood lead was analyzed before and after abatement in 37 homes of children under 7 years old with initial blood lead levels of 25-44 microgram/dL. Ninety-five percent of homes were built before 1950. Abatement methods used were wet-scraping and repainting deteriorated surfaces and wrapping window wells with aluminum or vinyl. A control group was retrospectively selected. Control children were under 7 years old, had initial blood lead levels of 25-44 microgram/dL and a follow-up level at least 28 days afterward, and did not have abatements performed in their homes between blood lead levels. After abatement, statistically significant declines occurred in the intervention children's blood lead levels. The mean decline was 22%, 1 to 6 months after treatment. After adjustment for seasonality and child's age, the mean decline was 6.0 microgram/dL, or 18%. The control children's blood levels did not decline significantly. There was a mean decline of 0.25 microgram/dL, or 0.39%. After adjustment for seasonality and age, the mean decline for control children was 1.6 microgram/dL, or 1.8%. Low-cost abatement and education are effective short-term interim controls.

Public response to elevated nitrate in drinking water wells in Wisconsin.

The authors conducted a survey by mail of Wisconsin families who had their well water tested for nitrate to (a) assess their awareness and compliance with the state's health advisories for nitrate, (b) evaluate their reaction(s) to their test results, and (c) compare demographic differences between exposure levels. Owners of contaminated wells (i.e., > 12.9 mg/l nitrate-nitrogen) were more likely to have lived on a farm, had lower annual incomes, and had older and shallower wells than families whose wells were low in nitrate (i.e., < 2.0 mg/l nitrate-nitrogen). Most respondents were aware of the advisories for pregnant women and infants and, in accordance with these advisories, the majority of families with nitrate-contaminated drinking water took no remedial action. Given that many rural families consume nitrate-contaminated water daily, scientists should conduct additional research to determine whether chronic ingestion of nitrate-contaminated water poses a significant health threat to these families.

Body burden levels of dioxin, furans, and PCBs among frequent consumers of Great Lakes sport fish. The Great Lakes Consortium.

Dioxins, furans, and polychlorinated biphenyls (PCBs) are toxic, persist in the environment, and bioaccumulate to concentrations that can be harmful to humans. Sport anglers may be exposed to these residues via consumption of contaminated Great Lakes (GL) fish. The Health Departments of five GL states, Wisconsin, Michigan, Ohio, Illinois, and Indiana, formed a consortium to study body burden levels of chemical residues in fish consumers of Lakes Michigan, Huron, and Erie. In Fall 1993, a telephone survey was administered to sport angler households to obtain fish consumption habits and demographics. A blood sample was obtained from a portion of the study subjects. One hundred serum samples were analyzed for 8 dioxin, 10 furan, and 4 coplanar PCB congeners. Multiple linear regression was conducted to assess the predictability of the following covariates: GL sport fish species, age, BMI, gender, years sport fish consumed, and lake. Of the 100 subjects, there were 58 men; 35 consumed sport fish from Lake Michigan, 29 from Lake Huron, and 36 from Lake Erie. The overall average number of GL sport fish meals consumed in the previous 12 months was 43. Lake Erie male and female consumers, on average, ate more GL sport fish, a mean of 57 and 42 meals, respectively, than men and women from the other two lake subgroups. Median total dioxin toxic equivalents (TEq), total furan TEq, and total coplanar PCB TEq were higher among all men than all women (P=0.0001). Lake trout, salmon, age, BMI, and gender were significant regression predictors of log(total coplanar PCBs). Lake trout, age, gender, and lake were significant regression predictors of log(total furans). Age was the only significant predictor of total dioxin levels.

Serum PCB and DDE levels of frequent Great Lakes sport fish consumers-a first look. The Great Lakes Consortium.

Great Lakes (GL) sport fish consumption is a potential human exposure route for polychlorinated biphenyls (PCBs) and dichlorodiphenyl dichloroethene (DDE). Because of fish tissue contamination, frequent consumers of Great Lakes sport caught fish (GLSCF) may be at risk for PCB and DDE accumulation. To examine this problem, the Health Departments of Wisconsin, Illinois, Indiana, Ohio, and Michigan formed a health assessment consortium. Participants were contacted by telephone to complete a detailed demographic and fish consumption survey. Frequent and infrequent GLSCF consumers were identified, and a participant subset was then asked to donate blood for PCB and DDE analysis. Analysis of variance (ANOVA) was done to study exposure group mean differences, while correlation and regression analyses were performed to examine relationships between demographic characteristics, GLSCF consumption, PCB, and DDE body burdens. A total of 4206 individuals participated in the study. Of these, 2542 were habitual GLSCF consumers (mean greater than 35 meals/year males; greater than 27 meals/year females), while 1664 did not eat GLSCF. A subset of 538 participants donated blood and included 439 frequent and 99 infrequent GLSCF consumers. PCB levels were significantly higher in the group of GLSCF consumers (geometric mean: 4.8 ppb males, 2.1 ppb females) when compared to their referents (geometric mean: 1.5 ppb males, 0.9 ppb females), while DDE levels were also higher for GLSCF consumers. PCB and DDE body burdens varied by exposure group, gender, and great lake (Michigan, Huron, Erie). PCB and DDE levels were significantly correlated to age, body mass index, and sport fish and Great Lakes sport fish consumption histories. Regression analysis identified years of consuming sport caught fish as the most robust predictor of PCBs (r2=25%), while age was the best predictor of DDE levels (r2=21%). This study corroborated previous findings relating frequent GLSCF consumption to a higher body burden for PCBs and DDE.

Osteosarcoma, seasonality, and environmental factors in Wisconsin, 1979-1989.

Proxy exposure measures and readily available data from the Wisconsin Cancer Reporting System were used to contrast 167 osteosarcoma cases with 989 frequency-matched cancer referents reported during 1979-1989. Differences in potential exposure to water-borne radiation and fluoridated drinking water, population size for the listed place of residence, and seasonality were assessed. An association was found between osteosarcoma and residence in a population of less than 9,000 (odds ratio = 1.6, 95% confidence interval = 1.1-2.4). In addition, an association between month of birth (May through July versus other months of birth) and osteosarcoma among individuals who were less than 25 y of age (odds ratio = 1.9, 95% confidence interval = 1.1-3.4). Overall, no association was found between potential exposure to fluoridated drinking water and osteosarcoma (odds ratio = 1.0, 95% confidence interval = 0.6-1.5). The association between osteosarcoma and water-borne radiation was weak and was not significant statistically (odds ratio = 1.5, 95% confidence interval = 0.8-2.8).

Behavioral risk factors of Chippewa Indians living on Wisconsin reservations.

Behavioral risk factors and chronic disease death rates vary markedly among the numerous American Indian tribes. Local data on prevalence of risk factors are important in determining effective community-based interventions. The authors conducted an in-person survey to ascertain the prevalence of behavioral risk factors among members of the Chippewa tribe living on reservations in Wisconsin. A total of 465 Chippewa adults were randomly selected from tribal registries and invited to participate in the study. Of these, 175 (38 percent) participated. To characterize nonrespondents, 75 nonrespondents were randomly selected and aggressively followed up. The authors compared their results with data from the 1989 Wisconsin Behavioral Risk Factor Surveillance System. Chippewa respondents reported high levels of obesity and tobacco use. No significant differences existed between the original survey and followback of nonrespondents. Compared with respondents who had telephones, those without telephones were significantly more likely to be unemployed, to be a current smoker or drinker, and to report nonuse of seatbelts. Compared with the general Wisconsin population, Chippewa adults appear to have higher prevalences of several chronic disease and injury risk factors. The original survey methodology, despite the low response rate, appeared to give a more accurate (less biased) estimate of risk factor prevalences than would have been achieved by a telephone survey.

Fish consumption patterns and blood mercury levels in Wisconsin Chippewa Indians.

Methylmercury is a known neurotoxin at high blood levels (> 400 micrograms/l) and is thought to cause neurologic symptoms at substantially lower levels in susceptible adults and infants. Given that levels of methylmercury in fish in northern Wisconsin lakes can be high (> 1 ppm, FDA standard) and Chippewa Indians take large amounts of fish from these lakes, the extent of their exposure to methylmercury was investigated. Using tribal-maintained registries, 465 Chippewa adults living on reservation were selected randomly and were invited to participate; 175 (38%) participated in the study. In an effort to characterize nonrespondents, 75 nonrespondents were selected randomly and were followed up aggressively. An additional 152 volunteers who were selected nonrandomly also participated in the study. Subjects completed a questionnaire about fish consumption patterns and had blood drawn for mercury determination. Sixty-four persons (20%) had blood mercury levels in excess of 5 micrograms/l (i.e., upper limit of normal in nonexposed populations); the highest level found was 33 micrograms/l. Fish consumption was higher in males and the unemployed. Blood mercury levels were highly associated with recent walleye consumption (p = .001). Methylmercury levels in some Wisconsin Chippewa were found to be elevated, but were below the levels associated with adverse health effects. We recommend a continuation of efforts to limit exposures in this high-risk population.

Fish consumption and reproductive outcomes in Green Bay, Wisconsin.

Prenatal exposure to polychlorinated biphenyls (PCBs) and reproductive outcome was determined in a population of 1112 women during 1987-1989. The women studied were from the Green Bay, Wisconsin area, thereby providing a population with potential PCB exposure from Lake Michigan sport fish consumption. All women with positive pregnancy tests from two Green Bay prenatal clinics were asked to complete a self-administered questionnaire on fish consumption, health and reproductive history, and other relevant issues and to provide blood samples for PCB analysis. A positive correlation was found between the amount of Lake Michigan fish mothers claimed to consume and their PCB serum levels. After the pregnancy period, reproductive outcome measures (fetal wastage; stillbirths; and birth weight, birth length, head circumference, ponderal index, and birth weight percentiles for live births) were abstracted from hospital labor reports. Typical negative associations between birth size measures and consumption of caffeine, smoking, and alcohol were found. Birth size was positively associated with gestational age, birth order, weight gain during pregnancy, male babies, and rural residence. Birth size was also associated with PCB exposure; however contrary to expectations, a positive association was found (P < 0.044) for most mothers (the exception being those mothers who gained more than 34 lb during their pregnancy). PCB exposures were lower than the other studies that found that birth size was negatively associated with PCB exposure.

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.

Epidemiological studies on ingested mineral fibres: gastric and other cancers.

The epidemiological studies of ingested asbestos fibres conducted world-wide are reviewed and evaluated. Most of the studies have been done in the United States and Canada and have involved community exposures via natural contamination of drinking-water supplies. One or more studies found associations between asbestos fibres in drinking-water supplies and cancer incidence or mortality associated with many body sites, including oesophagus, stomach, small intestine, colon, rectum, gall-bladder, lungs, pancreas, peritoneum, pleura, prostate, kidneys, brain and thyroid. Each study has methodological limitations or weaknesses that limit the ability to assess risk from ingested asbestos. There is no agreement between the results of the various studies, but an association between ingested asbestos fibres and cancer of the stomach and pancreas has been found with some degree of consistency.

Case-control study of colon cancer and drinking water trihalomethanes in Wisconsin.

A case-control study was conducted to test the hypothesis that chronic ingestion of trihalomethanes (THMs), occurring as chlorination byproducts in drinking water, carries a risk of colon cancer. Lifetime residential and water source histories and information on water-drinking habits, diet, sociodemographics, medical and occupation histories, lifestyle and other factors were obtained by questionnaire from a statewide sample of newly-diagnosed colon cancer cases (N = 347), controls with cancer of other sites (N = 639) and general population controls (N = 611). Since no data on past THM levels exists, it was necessary to devise a scheme to generate THM estimates for all Wisconsin water sources. For this, a statistical model based on quantitative THM measures and routinely-recorded data taken at 81 municipal water facilities was used in conjunction with individual residential histories to estimate lifetime and period-specific THM exposure for each case and control. Logistic regression was used to estimate odds ratios adjusted for age, sex and urban living, for colon cancer and THM exposure. The study results indicate that THM in Wisconsin drinking water does not pose a significant colon cancer risk. Odds ratios for exposure to the middle and highest category of lifetime cumulative THM were 1.05 (95% Cl = 0.66-1.68) and 0.93(95%Cl = 0.55-1.57) respectively, relative to the cancer control group, and 1.10 (95%Cl = 0.68-1.78) and 0.73 (95% Cl = 0.44-1.21) respectively, relative to the general population controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Thermotolerant non-fecal source Klebsiella pneumoniae: validity of the fecal coliform test in recreational waters.

Wisconsin pulp and paper mill processing plants were evaluated for fecal coliform and total Klebsiella (i.e., thermotolerant and thermointolerant) bacterial concentrations. Using the standard fecal coliform test, up to 90 per cent of non-fecal source thermotolerant K. pneumoniae was falsely identified as fecal source bacteria. Since there is a lack of specificity in the currently used standard for fecal coliform evaluation, a more reliable health risk assessment for fecal coliform bacteria is recommended.

Formaldehyde vapor in mobile homes: a cross sectional survey of concentrations and irritant effects.

Sixty-five Wisconsin mobile home households volunteered for an assessment of indoor formaldehyde gas. Sixty-one teenage and adult occupants completed health questionnaires. Formaldehyde concentrations ranged from less than 0.10 to 0.80 ppm, with the risk of ocular discomfort showing a positive dose-response relationship.

Conceptual/operational criteria of causality: relevance to systematic epidemiologic theory.

Emphasis has recently been placed on the possibility of developing "unified" criteria of causality applicable to both the infectious and chronic, non-infectious diseases. Yet, contemporary efforts are essentially compilations of criteria established over the past 140 years, without provision of the conceptual basis allowing such a unification. From hierarchical views of the natural history of infectious and neoplastic (i.e., chronic non-infectious) disease, it is possible to identify discipline and natural history-related concepts of causation from which it is possible to derive conceptual criteria of causality and complementary operational criteria of causality. These criteria are entirely relevant to the comprehension of disease as both product and process and applicable to both the infectious and neoplastic diseases.

Outline to the investigation of an environmental exposure.

There is ever increasing concern whether potentially toxic environmental conditions are adversely impacting the health of the human population at risk of exposure. Traditional methods of epidemiology and other health related research disciplines have the reverse orientation, as they start with the occurrence of an epidemic, or a certain rate of disease in the population, and then seek the causes of that disease incidence. Traditional study designs offer much in the methods of disease/epidemic investigation, but less is available in the methods of exposure investigation. An introductory outline is offered here detailing the nature of the steps to be taken and their rationale in consideration of the health consequences of an environmental exposure.