A pilot study on the feasibility of European harmonized human biomonitoring: Strategies towards a common approach, challenges and opportunities.

In 2004 the European Commission and Member States initiated activities towards a harmonized approach for Human Biomonitoring surveys throughout Europe. The main objective was to sustain environmental health policy by building a coherent and sustainable framework and by increasing the comparability of data across countries. A pilot study to test common guidelines for setting up surveys was considered a key step in this process. Through a bottom-up approach that included all stakeholders, a joint study protocol was elaborated. From September 2011 till February 2012, 17 European countries collected data from 1844 mother-child pairs in the frame of DEMOnstration of a study to COordinate and Perform Human Biomonitoring on a European Scale (DEMOCOPHES).(1) Mercury in hair and urinary cadmium and cotinine were selected as biomarkers of exposure covered by sufficient analytical experience. Phthalate metabolites and Bisphenol A in urine were added to take into account increasing public and political awareness for emerging types of contaminants and to test less advanced markers/markers covered by less analytical experience. Extensive efforts towards chemo-analytical comparability were included. The pilot study showed that common approaches can be found in a context of considerable differences with respect to experience and expertize, socio-cultural background, economic situation and national priorities. It also evidenced that comparable Human Biomonitoring results can be obtained in such context. A European network was built, exchanging information, expertize and experiences, and providing training on all aspects of a survey. A key challenge was finding the right balance between a rigid structure allowing maximal comparability and a flexible approach increasing feasibility and capacity building. Next steps in European harmonization in Human Biomonitoring surveys include the establishment of a joint process for prioritization of substances to cover and biomarkers to develop, linking biomonitoring surveys with health examination surveys and with research, and coping with the diverse implementations of EU regulations and international guidelines with respect to ethics and privacy.

Interpreting biomarker data from the COPHES/DEMOCOPHES twin projects: Using external exposure data to understand biomarker differences among countries.

In 2011 and 2012, the COPHES/DEMOCOPHES twin projects performed the first ever harmonized human biomonitoring survey in 17 European countries. In more than 1800 mother-child pairs, individual lifestyle data were collected and cadmium, cotinine and certain phthalate metabolites were measured in urine. Total mercury was determined in hair samples. While the main goal of the COPHES/DEMOCOPHES twin projects was to develop and test harmonized protocols and procedures, the goal of the current paper is to investigate whether the observed differences in biomarker values among the countries implementing DEMOCOPHES can be interpreted using information from external databases on environmental quality and lifestyle. In general, 13 countries having implemented DEMOCOPHES provided high-quality data from external sources that were relevant for interpretation purposes. However, some data were not available for reporting or were not in line with predefined specifications. Therefore, only part of the external information could be included in the statistical analyses. Nonetheless, there was a highly significant correlation between national levels of fish consumption and mercury in hair, the strength of antismoking legislation was significantly related to urinary cotinine levels, and we were able to show indications that also urinary cadmium levels were associated with environmental quality and food quality. These results again show the potential of biomonitoring data to provide added value for (the evaluation of) evidence-informed policy making.

Trace element nutrition in developing countries.

Trace element status in humans is often poorly established in developed, let alone developing, countries. There have been assumptions about inevitable adequacy, especially for ultra-trace elements, like chromium, with varied diets. However, new pressures on trace element adequacy are emerging, like developments in food technology with the new formulated foods and element pollutants (toxic metals) with potential interactions with essential elements. Improved, more sensitive methods for trace element measurements in foods and biological specimens, functional indices of trace element status, with application to nutritional epidemiology, and the pursuit of clinical trials, should allow appropriate revision of current views. This process is likely to more consequential in developing countries.

When home caregiving ends: a longitudinal study of outcomes for caregivers of relatives with dementia.

OBJECTIVES: To study caregivers' decisions to end home care for relatives with dementia; to study the changes in caregiver functioning over time. DESIGN: A prospective longitudinal follow-up study. SETTING: Individual homes and chronic care facilities in Montreal. PARTICIPANTS: 157 caregiver-dependent dyads, followed up 2 years later; dependents had been diagnosed as having progressive dementia. MEASUREMENTS: A standard interview and a series of standardized psychological questionnaires were given to caregivers, assessing their functioning and their appraisals of the dependent person in their care. Dependents received the Mini-Mental State Examination. MAIN RESULTS: Caregivers cited patient deterioration as the most common reason for ending home care. Most caregivers did not prepare their relative before institutionalization. Most caregivers were satisfied with having ended home care and believed the decision was positive for themselves and their dependent, but a sizable minority of caregivers and dependents had difficulty adjusting to the end of home care. Repeated measures multivariate analyses indicated that caregivers who had discontinued home care because of placement or death of the dependent had improved functioning and quality of life and better health than caregivers still providing home care. CONCLUSIONS: Caregivers most frequently cite deteriorating patient conditions as the main causes of ending home care. Caregiver exhaustion is the single most frequently given reason. Caregivers who were still providing home care at the end of the study were functioning less well than caregivers who had ended home care, despite having initially functioned at better levels.

Personality traits as determinants of burden and health complaints in caregiving.

This study tested predictions specifying the influence of caregiver personality traits on negative outcomes of caregiving, health complaints and burden. Two-hundred and thirteen caregivers, who were caring for family members with dementia, were interviewed and their relatives were assessed on cognitive status and aggression. At follow-up conducted twenty-four months later, forty-five caregivers were still continuing to provide home care for their dependents. Caregivers who scored higher on a measure of neuroticism experienced higher levels of burden and health complaints both at initial and follow-up assessment. Caregiver extraversion-introversion did not influence the experience of caregiving. At both initial and final assessment, the ability to enjoy some aspects of caregiving, recreational activities, and satisfaction with social support from family and friends mitigated negative outcomes of caregiving, while appraising the dependent as more troublesome increased negative outcomes. Caring for more cognitively impaired and more aggressive dependents and being female increased negative outcomes initially. Personality traits and most other study variables demonstrated significant continuity across time for caregivers continuing home care.

Trace element contents in food determined by neutron activation analysis and other techniques.

Advances in analytical methodology and sophisticated instrumentation introduced during the last few decades have not only helped to recognize the presence of a large number of essential and toxic trace elements in biological materials and food stuffs, but also added a new dimension in our understanding of their role in health and disease. In deficiency states, most essential trace elements cause health problems. The trace element problem as a public health issue has a very low priority in developing countries. Daily dietary intake data based on well-conducted studies are limited in many parts of the world. The present authors are in the process of generating data for the intake levels of a number of major and minor inorganic elements both in developed and developing countries. The results so far obtained show wide variations. The intake levels of several elements, including potassium, magnesium, zinc, copper, and selenium, are below the current recommended levels. The concentration of toxic metals, such as aluminum, cadmium, lead, and mercury, are within acceptable limits in most of the diets analyzed.

Validation of the cumulative or replicate NAA method for the determination of trace elements in biological materials.

To make the best use of time and facilities, a neutron activation system, fully automatic, including spectrum and data processing, to be used with short-lived nuclides, has been recently developed at the Portuguese Research Reactor (in Portuguese "Reactor Portugês de Investigação," RPI). Using this system, the cumulative neutron activation analysis method is now being implemented. This article summarizes the experimental procedures used to validate the cumulative NAA method for the determination of selenium in biological samples, emphasizing the determination of the essential characteristics of precision, accuracy, and limits of detection and of quantification of the method. The article also examines how detection limits and precision are improved when the samples are analyzed by this method compared to the cyclic activation measurements in use at RPI for the determination of selenium. The improvement is demonstrated for the measurement of selenium in several reference materials when the result obtained by adding up seven spectra of separate aliquots of the same sample is compared to the result from a cumulative spectrum of seven (whenever possible) consecutive cycles of a single sample.

Factor for correcting the ruthenium interference in instrumental neutron activation analysis of barium in uraniferous samples.

The fission spectral interference of ruthenium on the instrumental neutron activation analysis of barium in samples containing uranium is extensively discussed. In particular the dependence of the correction factor on the phi epi/phi th ratio is studied. An excellent agreement between experimental and calculated values is achieved. A procedure is suggested for the resolution of multiple interferences in the general case where uranium, barium and/or ruthenium are present in samples to be analysed.

Determination of selenium in duplicate diets of residents of Pinhel, Portugal, by neutron activation.

A rapid cyclic instrumental neutron activation analysis (CINAA) method has been used to determine the selenium content of 27 duplicate diet samples from each of the 27 districts surrounding Pinhel, Portugal. The accuracy and precision of the CINAA method have been evaluated by analyzing certified reference materials and observed to be within +/- 5-10% for samples containing at least 40 ppb of selenium. The detection limit has been found to vary between 26-42 ppb selenium depending on the sample composition. The average daily dietary intake has been calculated as 37 micrograms of selenium per day.