A baseline survey of dissolved methane in aquifers of Great Britain.

Interest in dissolved methane (CH4) concentrations in aquifers in England, Scotland and Wales ('Great Britain' or GB) has grown concurrently with interest in the exploitation of unconventional gas sources (UGS). Experience, mainly from North America, has shown the importance of a pre-production baseline against which changes possibly due to UGS extraction can be compared. The British Geological Survey, aided by water utilities, private users and regulators, has compiled a unique dataset for CH4 in groundwaters of GB. This focuses principally on areas where UGS exploration is considered more likely, as indicated by the underlying geology. All the main water supply aquifers (Principal aquifers) were targeted, plus Secondary aquifers where locally important. The average dissolved CH4 concentration across GB in the aquifers sampled was 45µg/l. Out of a total of 343 sites, 96% showed dissolved CH4 concentrations <100µg/l, 80% <10µg/l, and 43%<1µg/l. No site had a CH4 concentration above the US Department of the Interior suggested risk action level of 10,000µg/l. While most sites were sampled only once, a subset was monitored quarterly to determine the magnitude of seasonal or other variations. Generally these variations were minor, with 84% of sites showing variations within the range 0.5-37µg/l, but some aquifers where the porosity was primarily fracture-related showed larger changes (0.5-264µg/l). This may have been due to the nature of sampling at these sites which, unlike the others, did not have installed pumps. Since the regulatory compliance monitoring attending UGS operations will include the measurement of parameters such as dissolved CH4, it is essential that sampling methods are tested to ensure that reliable and comparable datasets can be obtained.

Tracing enteric pathogen contamination in sub-Saharan African groundwater.

Quantitative PCR (qPCR) can rapidly screen for an array of faecally-derived bacteria, which can be employed as tracers to understand groundwater vulnerability to faecal contamination. A microbial DNA qPCR array was used to examine 45 bacterial targets, potentially relating to enteric pathogens, in 22 groundwater supplies beneath the city of Kabwe, Zambia in both the dry and subsequent wet season. Thermotolerant (faecal) coliforms, sanitary risks, and tryptophan-like fluorescence, an emerging real-time reagentless faecal indicator, were also concurrently investigated. There was evidence for the presence of enteric bacterial contamination, through the detection of species and group specific 16S rRNA gene fragments, in 72% of supplies where sufficient DNA was available for qPCR analysis. DNA from the opportunistic pathogen Citrobacter freundii was most prevalent (69% analysed samples), with Vibrio cholerae also perennially persistent in groundwater (41% analysed samples). DNA from other species such as Bifidobacterium longum and Arcobacter butzleri was more seasonally transient. Bacterial DNA markers were most common in shallow hand-dug wells in laterite/saprolite implicating rapid subsurface pathways and vulnerability to pollution at the surface. Boreholes into the underlying dolomites were also contaminated beneath the city highlighting that a laterite/saprolite overburden, as occurs across much of sub-Saharan aquifer, does not adequately protect underlying bedrock groundwater resources. Nevertheless, peri-urban boreholes all tested negative establishing there is limited subsurface lateral transport of enteric bacteria outside the city limits. Thermotolerant coliforms were present in 97% of sites contaminated with enteric bacterial DNA markers. Furthermore, tryptophan-like fluorescence was also demonstrated as an effective indicator and was in excess of 1.4µg/L in all contaminated sites.

In-situ tryptophan-like fluorescence: A real-time indicator of faecal contamination in drinking water supplies.

Enteric pathogens are typically inferred from the presence of surrogate indicator organisms such as thermotolerant (faecal) coliforms (TTCs). The analysis of TTCs requires time-consuming incubation in suitable laboratories, which can limit sampling resolution, particularly during critical pollution events. Here, we demonstrate the use of in-situ fluorimeters targeting tryptophan-like compounds as a rapid, reagentless indicator of TTCs in groundwater-derived potable water supplies in Africa. A range of other common indicators of TTCs were also determined including nitrate, turbidity, and sanitary risk survey scores. Sampling was conducted during both the dry and wet seasons to investigate seasonality. Tryptophan-like fluorescence was the most effective predictor of both presence/absence and number of TTCs during both seasons. Seasonal changes in tryptophan-like fluorescence in deeper supplies suggest it is transported more efficiently through the aquifer than TTCs. Moreover, the perennial elevated concentrations in some wells suggest it is more resilient than TTCs in groundwater. Therefore tryptophan-like fluorescence could also be a better indicator of some smaller, more easily transported, and long-lived, pathogenic enteric viruses. These sensors have the potential to be included in real-time pollution alert systems for drinking water supplies throughout the world, as well as for mapping enteric pathogen risks in developing regions.

Emerging contaminants in urban groundwater sources in Africa.

The occurrence of emerging organic contaminants within the aquatic environment in Africa is currently unknown. This study provides early insights by characterising a broad range of emerging organic contaminants (n > 1000) in groundwater sources in Kabwe, Zambia. Groundwater samples were obtained during both the dry and wet seasons from a selection of deep boreholes and shallow wells completed within the bedrock and overlying superficial aquifers, respectively. Groundwater sources were distributed across the city to encompass peri-urban, lower cost housing, higher cost housing, and industrial land uses. The insect repellent DEET was ubiquitous within groundwater at concentrations up to 1.8 µg/L. Other compounds (n = 26) were detected in less than 15% of the sources and included the bactericide triclosan (up to 0.03 µg/L), chlorination by-products - trihalomethanes (up to 50 µg/L), and the surfactant 2,4,7,9-tetramethyl-5-decyne-4,7-diol (up to 0.6 µg/L). Emerging contaminants were most prevalent in shallow wells sited in low cost housing areas. This is attributed to localised vulnerability associated with inadequate well protection, sanitation, and household waste disposal. The five-fold increase in median DEET concentration following the onset of the seasonal rains highlights that more mobile compounds can rapidly migrate from the surface to the aquifer suggesting the aquifer is more vulnerable than previously considered. Furthermore it suggests DEET is potentially useful as a wastewater tracer in Africa. There was a general absence of personal care products, life-style compounds, and pharmaceuticals which are commonly detected in the aquatic environment in the developed world. This perhaps reflects some degree of attenuation within the subsurface, but could also be a result of the current limited use of products containing emerging contaminants by locals due to unaffordability and unavailability. As development and population increases in Africa, it is likely a wider-range of emerging contaminants will be released into the environment.

Change in DASH diet score and cardiovascular risk factors in youth with type 1 and type 2 diabetes mellitus: The SEARCH for Diabetes in Youth Study.

Youth with diabetes are at an increased risk of cardiovascular disease (CVD). Adherence to the Dietary Approaches to Stop Hypertension (DASH) diet has been shown to improve CVD risk. In this study, we evaluated whether changes in diet quality as characterized by DASH are associated with changes in CVD risk factors in youth with diabetes over time. Longitudinal mixed models were applied to data from 797 participants in the SEARCH for Diabetes in Youth Study representing three time points: baseline, 12- and 60-month follow-up. Data were restricted to youth whose diabetes was first diagnosed in 2002-2005. DASH-related adherence was poor and changed very little over time. However, an increase in DASH diet score was significantly associated with a decrease in HbA1c levels in youth with type 1 diabetes (ß=-0.20, P-value=0.0063) and a decrease in systolic blood pressure among youth with type 2 diabetes (ß=-2.02, P-value=0.0406). Improvements in dietary quality may be beneficial in youth with type 1 or type 2 diabetes. However, further work in larger groups of youth with type 1 and 2 diabetes is desirable.

Exercise and mononuclear cell DNA damage: the effects of antioxidant supplementation.

The purpose of this investigation was to determine the effects of antioxidant supplementation on DNA damage following exercise. Fourteen subjects were randomly assigned to one of two groups and required to ingest either antioxidants (400 mg alpha-lipoic acid, 200 mg co-enzyme Q10, 12 mg manganese, 600 mg vitamin C, 800 mg N-acetyl cysteine, 400 microg selenium, and 400 IU alpha-tocopherol per day) or placebos for 7 d. Exercise increased DNA damage, PS, FRAP, and LDH (P < 0.05), but not selectively between groups. LDH and PS concentration decreased 1 h post-exercise (P < 0.05), while LH concentration decreased 1 h post-exercise in the antioxidant group only (P < 0.05). The antioxidant group had a higher concentration of LH (P < 0.05), perhaps due to a selective difference between groups post-exercise (P < 0.05). The main findings of this investigation demonstrate that exhaustive aerobic exercise induces DNA damage, while antioxidant supplementation does not protect against damage.

International variation in pancreatic cancer mortality for the period 1955-1998.

BACKGROUND: Pancreatic cancer is an important cause of cancer mortality in developed countries. This article examines time trends for pancreatic cancer mortality rates in 38 countries on five continents between 1955 and 1998. METHODS: We used the World Health Organization database on Age-Standardized World Population pancreatic cancer mortality rates by gender and fitted these data with linear regression models. This allowed us to (1) investigate the statistical significance of temporal trends; and (2) consider differences in trends among countries; and (3) predict future pancreatic cancer mortality rates. RESULTS: Over 44 years, pancreatic cancer mortality rates increased for females worldwide. Pancreatic cancer mortality rates for men increased in Southern Europe. In contrast, pancreatic cancer mortality rates for men in North America and Oceania increased until about 1975 and then decreased or remained stable. Our predictive models suggest that by 2005 the relative burden of pancreatic cancer mortality will have shifted away from Northern Europe and North America toward Southern Europe and Asia. CONCLUSIONS: Future research on pancreatic cancer should concentrate separately on the assessment of risk attributable to exposure to environmental factors, lifestyle factors, genetic determinates of pancreatic cancer, and the interactive influences of these factors on pancreatic cancer.

Investigating correlates of health related quality of life in a low-income sample of patients with diabetes.

OBJECTIVE: We sought to describe and find correlates of health-related quality of life among under-served low-income patients in North Carolina with diabetes mellitus. METHODS: A telephone survey of 310 patients recording quality of life, patient satisfaction, self-reported health, and patient complaints was conducted as part of a diabetes care improvement project. Demographic and clinical records were available for 249 of these patients: 69% were female, 45% were minority, and 84% had type 2 diabetes. Ages ranged from 18 to 88 years with a mean of 56. Quality of life indices consisted of SF-36 physical functioning, mental health and diabetes-39 sub-scores. RESULTS: Comparison to SF-36 norms showed the sample had lower sub-scores than expected. The multivariate analysis suggested that being within an acceptable metabolic control predicted better quality of life physically, mentally, and sexually. Strong associations were detected between most sub-scores and complaints involving legs and feet, self-rated vision, and hassles in self-management. CONCLUSIONS: The consistent associations between the sub-scores and complaints, symptoms, and hassles underscore the strong relationship quality of life may share with the severity of diabetes complications as well as with psychosocial factors. Significantly lower quality of life in this sample highlights the need to improve the care of minority low-income diabetes patients.

Geographic variation in cardiovascular disease risk factors among American Indians and comparisons with the corresponding state populations.

OBJECTIVES: (1) To compare the prevalence of self-reported CVD, diabetes, hypertension, fair/poor perceived health status, and current tobacco use from three surveys of American Indians - two in the Southeast (Catawba Diabetes and Health Survey [CDHS] and Lumbee Diabetes and Health Survey [LDHS]) and one in the upper Midwest (Inter-Tribal Heart Project [ITHP]). (2) To compare the prevalence estimates from the CDHS, LDHS, ITHP with those for the corresponding state populations (South Carolina, North Carolina, Minnesota and Wisconsin, respectively) derived from the Behavioral Risk Factor Surveillance System (BRFSS). METHODS: Pearson's Chi-square analyses were used to detect statistically significant differences in the age-adjusted prevalence estimates across the study populations. RESULTS: Among these three populations of American Indians, the ITHP participants had the highest prevalence estimates of diabetes (20.1%) and current cigarette smoking (62.8%). The CDHS participants had the highest prevalence estimate of fair/poor perceived health status (32.0%). The LDHS participants had the highest prevalence estimate of chewing tobacco use (14.0%), and the lowest prevalence of CVD. The prevalence estimates of self-reported diabetes were dramatically higher among American Indian participants in the ITHP (20.1%) and CDHS (14.9%) than among participants in the corresponding state BRFSS (5.8% MN and WI and 6.6% SC), as were the estimates for hypertension. CONCLUSION: The substantial variations in prevalence of CVD and its risk factors among Tribal Nations suggests that distinct cultural norms, historic conditions, and important health issues of each American Indian community must be recognized and incorporated into all health promotion programs and policies.

When physicians and patients think alike: patient-centered beliefs and their impact on satisfaction and trust.

OBJECTIVE: Our goal was to identify physician and patient characteristics associated with patient-centered beliefs about the sharing of information and power, and to determine how these beliefs and the congruence of beliefs between patients and physicians affect patients' evaluations. STUDY DESIGN: Physicians completed a scale assessing their beliefs about sharing information and power, and provided demographic information. A sample of their patients filled out the same scale and made evaluations of their physicians before and after a target visit. POPULATION: Physicians and patients in a large multispecialty group practice and a group model health maintenance organization were included. Forty-five physicians in internal medicine, family practice, and cardiology participated, as well as 909 of their patients who had a significant concern. OUTCOMES MEASURED: Trust in the physician was measured previsit, and visit satisfaction and physician endorsement were measured immediately postvisit. RESULTS: Among patients, patient-centered beliefs (a preference for information and control) were associated with being women, white, younger, more educated, and having a higher income; among physicians these beliefs were unrelated to sex, ethnicity, or experience. The patients of patient-centered physicians were no more trusting or endorsing of their physicians, and they were not more satisfied with the target visit. However, patients whose beliefs were congruent with their physicians' beliefs were more likely to trust and endorse their physicians, even though they were not more satisfied with the target visit. CONCLUSIONS: The extent of congruence between physicians' and patients' beliefs plays an important role in determining how patients evaluate their physicians, although satisfaction with a specific visit and overall trust may be determined differently.

Staying healthy: the salience and meaning of health maintenance behaviors among rural older adults in North Carolina.

Beliefs about what constitutes health promoting behaviors vary by culture and class, and knowing how an older adult interprets a specific health behavior can improve health education and medical compliance. Ethnomedical approaches have investigated how people define disease and the therapies used to return to a state of health. However, little research has addressed how individuals define health, or the behaviors they use to maintain health. We analyze the behaviors elders state are needed to stay healthy, and their meanings for these behaviors. Narratives collected through in-depth interviews with 145 male and female rural North Carolina residents aged 70 and older, including African Americans, Native Americans and European Americans are analyzed using systematic text analysis. The participants' narratives include seven salient health maintenance domains: (1) Eating Right, (2) Drinking Water, (3) "Taking" Exercise, (4) Staying Busy, (5) Being with People, (6) Trusting in God and Participating in Church, and (7) Taking Care of Yourself. Several of these domains are multi-dimensional in the meanings the elders ascribe to them. There is also overlap in the content of some of the domains; they are not discrete in the minds of the elders and a specific health behavior can reflect more than one domain. Four themes cross-cut the domains: "balance and moderation", "the holistic view of health", "social integration", and "personal responsibility". Elders in these rural communities hold a definition of health that overlaps with, but is not synonymous with a biomedical model. These elders' concept of health seamlessly integrates physical, mental, spiritual, and social aspects of health, reflecting how health is embedded in the everyday experience of these elders. Staying healthy is maintaining the ability to function in a community. These results indicate that providers cannot assume that older patients will share their interpretation of general health promotion advice.

Unsaid but not forgotten: patients' unvoiced desires in office visits.

OBJECTIVES: To examine patient, physician, and health care system characteristics associated with unvoiced desires for action, as well as the consequences of these unspoken requests. PATIENTS AND METHODS: Patient surveys were administered before, immediately after, and 2 weeks after outpatient visits in the practices of 45 family practice, internal medicine, and cardiology physicians working in a multispecialty group practice or group model health maintenance organization. Data were collected at the index visit from 909 patients, of whom 97.6% were surveyed 2 weeks after the outpatient visit. Before the visit, patients rated their trust in the physician, health concerns, and health status. After the visit, patients reported on various types of unexpressed desires and rated their visit satisfaction. At follow-up, patients rated their satisfaction, health concerns, and health status, and also described their postvisit health care use. Evaluations of the visit were also obtained from physicians. RESULTS: Approximately 9% of the patients had 1 or more unvoiced desire(s). Desires for referrals (16.5% of desiring patients) and physical therapy (8.2%) were least likely to be communicated. Patients with unexpressed desires tended to be young, undereducated, and unmarried and were less likely to trust their physician. Patients with unvoiced desires evaluated the physician and visit less positively; these encounters were evaluated by physicians as requiring more effort. Holding an unvoiced desire was associated with less symptom improvement, but did not affect postvisit health care use. CONCLUSIONS: Patients' unvoiced needs affect patients' and physicians' visit evaluations and patients' subjective perceptions of improvement. Implications of these findings for clinical practice are examined.

Quality of diabetes care among low-income patients in North Carolina.

BACKGROUND: Diabetes is a leading cause of death and disability, disproportionately affecting most ethnic minority groups, people of low socioeconomic status, the elderly, and people in rural areas. Despite the availability of evidence-based clinical recommendations, barriers exist in the delivery of appropriate diabetes care. The purpose of this study is to examine the level of diabetes care among low-income populations in North Carolina. METHODS: Baseline medical record abstractions were performed (N=429) on diabetic patients at 11 agencies serving low-income populations (community health centers, free clinics, primary care clinics, and public health clinics) across the state participating in a quality-of-diabetes-care initiative. Data were collected for four process (measurement of glycosylated hemoglobin and lipids, dilated eye examination, nephropathy assessment) and two outcome (glycemic and lipid control) measures based on the Diabetes Quality Improvement Project (DQIP) and the Health Plan Employer Data and Information Set (HEDIS), and three additional indicators (blood pressure measurement and control, and lower limb assessment). Compliance rates to individual measures were calculated overall and by demographic and health characteristics. RESULTS: Diabetes care compliance rates ranged from 77.9% for blood pressure testing to 3.3% for complete foot examinations. Differences in care were observed by age, insulin use, and prevalent disease. CONCLUSIONS: This study indicates low compliance with diabetes care guidelines in underserved North Carolinians, and inconsistency of care according to some demographic and health characteristics. These results stress the need for quality improvement initiatives that enhance the level of care received by patients with diabetes, particularly those most vulnerable to diabetes and its complications.

Smokeless tobacco and osteoporosis: a new relationship?

Osteoporosis is a common disorder of bone predominantly affecting postmenopausal women in which bone mineral density declines making bone more likely to break. Although cigarette smoking is a well-established risk factor for osteoporosis, smokeless tobacco (ST) use has never been suggested or evaluated as a risk factor for this bone disorder. This would be important to consider since in certain regions of the world, ST use is more prevalent than cigarette smoking, particularly among women. This paper reviews the animal and human evidence lending support to this new hypothesis, as well as the epidemiology of ST use that underscores the potential impact this modifiable behavior might have on osteoporosis world wide.

Dual Tobacco use among Native American adults in southeastern North Carolina.

OBJECTIVE: While patterns of smokeless tobacco (ST) use and cigarette smoking are well documented, the epidemiology of simultaneous use of both tobacco products is less well studied, particularly among Native American populations. This study examines correlates of dual tobacco use among Lumbee Indian adults in southeastern North Carolina. METHODS: A telephone survey among 400 adult Lumbee Indians in Pembroke, North Carolina, collected information on demographics, current tobacco use, amounts of tobacco used, and tobacco related attitudes. RESULTS: Total of 241 (60.3%) individuals did not currently use tobacco, 104 (26%) currently smoked, 74 (18.5%) currently used ST, and 19 (4.8%) used both products. Thus, 19 of 104 (18.3%) current smokers and 19 of 74 (25.7%) current ST users reported dual tobacco use. Compared to exclusive users of either tobacco product, dual tobacco users were intermediate in age and frequency of church attendance, had lower levels of education, and were the highest proportion of subjects reporting no friends and few close relatives. There was no difference by gender or marital status by tobacco use categories. While exclusive cigarette smokers reported smoking more cigarettes per day than dual tobacco users, overall, dual tobacco users had higher estimated daily nicotine exposure levels. Logistic regression analysis showed that younger age and infrequent church attendance predicted exclusive cigarette smoking, while older age and less education predicted exclusive ST use. Dual tobacco use was predicted only by less education. CONCLUSIONS: Simultaneous use of ST and cigarettes is comparatively more common among Lumbee Indian adults than the general population and has an epidemiology distinct from either exclusive cigarette smoking or ST use. These data are the first to explore social support as well as tobacco-related attitudes among dual tobacco users in a Native American population. Recognition of these patterns of dual tobacco use would be important in any future tobacco intervention among Lumbee Indian adults.

Daily access to pasture turnout prevents loss of mineral in the third metacarpus of Arabian weanlings.

Seventeen Arabian weanlings were used to determine the influence of housing on third metacarpal bone mass. Animals were separated into three treatment groups: Pasture (n = 6), Stall (n = 5), and Partial-Pasture (n = 6). Radiographs of the left third metacarpus were taken every 28 d to determine radiographic bone aluminum equivalence (RBAE). Serum was collected every 14 d and analyzed for osteocalcin, carboxyterminal telopeptide of type I collagen (ICTP), and keratan sulfate. Hip and wither height, BW, and cannon circumference were measured every 28 d. Lateral RBAE in the pastured group increased linearly from d 0 to d 56 (P = 0.001). In the Pasture group, total RBAE increased from d 0 to 56 (P = 0.05) and medial RBAE tended to increase from d 0 to d 28 (P = 0.06). The Partial Pasture group increased from d 0 to 56 in medial (P = 0.02) and tended to increase in total RBAE (P = 0.08). Although the Stall group demonstrated an increase in total RBAE from d 0 to 56 (P = 0.04), the Partial Pasture group tended to have greater total RBAE than the Stall group at d 28 (P = 0.08), and the Pasture group had greater lateral RBAE at d 28 (P = 0.005) and 56 (P = 0.007) than did the Stall group. At d 28, medial RBAE was greater in the Pasture (P = 0.003) and Partial Pasture (P = 0.05) groups than in the Stall group. Pasture and Stall groups tended to decrease in osteocalcin (P = 0.06), whereas Partial Pasture weanlings decreased (P = 0.01) from d 0 to 56. All treatment groups decreased from d 0 to 56 in ICTP (P < 0.01). Pastured weanlings decreased from d 0 to 42 in serum keratin sulfate (P < 0.05), whereas the Stall group decreased from d 0 to 56 (P = 0.05). All treatment groups increased in wither height (P < or = 0.01), hip height (P < or = 0.001), and BW (P < or = 0.01). Both the Pasture and Partial Pasture weanlings demonstrated greater cannon circumference than Stall weanlings on d 28 (P < or = 0.05) and 56 (P < or = 0.005). These data demonstrate that pasture rearing or 12-h daily turnout is beneficial to maintaining and increasing bone mineral content in weanling Arabian horses.

Association between smokeless tobacco use and breast cancer among Native-American women in North Carolina.

BACKGROUND: Cigarette smoking and smokeless tobacco use have been associated with the development of a variety of cancers. While cigarette smoking may be associated with breast cancer, smokeless tobacco use has never been evaluated as a breast cancer risk factor. This study explores such an association. METHODS: A complete census was carried out among Eastern Band Cherokee women aged 18 years and older, residing on tribal lands in western North Carolina. Self-reported alcohol, cigarette and smokeless tobacco use, demographic information, and personal history of breast cancer (stratified by age of onset < 55 years or > or = 55 years) were obtained by questionnaire. RESULTS: 1,070 out of 1,408 (76%) eligible women were interviewed. Current and former smokeless tobacco use was common (6% and 21%, respectively). Five cases of breast cancer were identified in women under the age of 55 years and 3 cases were found in women at > or = 55 years. Only the odds ratio (OR) for younger-onset breast cancer among ever-users of smokeless tobacco was significantly elevated (OR = 7.79, 95% CI = 1.05-66.0). While the ORs for younger onset breast cancer were elevated among ever-smokers or women reporting at least monthly alcohol use, these were not significant (OR 8.49, 95% CI = 0.09-200; and OR = 1.72, 95% CI = 0.19-15.2, respectively). No ORs were significantly elevated for breast cancer among older women. CONCLUSIONS: These preliminary data are the first to document an apparent relationship between smokeless tobacco use and breast cancer risk, but should be confirmed in other studies due to the small number of cases. The nearly 8-fold increase in risk suggests that smokeless tobacco is not a safe alternative to cigarette smoking.