Differential effects of endogenous lithium on neurobehavioural functioning: a study on auditory evoked potentials.

Lithium occurs naturally in food and water. Low environmental concentrations in drinking water are associated with mental illnesses and behavioural offences, and at therapeutic dosages it is used to treat psychiatric (especially affective) disorders, partly by facilitating serotonergic (5-HT) neurotransmission. As little is known about the psychophysiological role of nutritional lithium in the general population, endogenous lithium concentrations were hypothesised to be associated with measurable effects on emotional liability and the loudness dependence (LD) that is proposed as one of the most valid indicators of 5-HT neurotransmission. Auditory evoked potentials of healthy volunteers [N=36] with high (>2.5 microg/l) or low (<1.5 microg/l) lithium serum concentrations were recorded. Emotional liability was assessed using the Brief Symptom Inventory (BSI). Low-lithium levels correlated with Somatisation while correlations between lithium and LD were not significant. Still, LD correlated positively with Paranoid Ideation, negatively with Anxiety and, in the high-lithium group, inversely with further aspects of emotional liability (Depression, Psychological Distress). In conclusion, the effects of low levels of endogenous lithium are associated with emotional liability, and high levels with some protective effects, although findings remain inconclusive regarding LD. Potential benefits of endogenous lithium on neurobehavioural functioning, especially in high-risk individuals, would have public health implications.

Clinical environmental medicine.

INTRODUCTION: Clinical environmental medicine deals with environmental effects on human health in individual patients. Patients seek medical advice for problems of many different kinds that may be due to environmental exposures; such exposures must be considered carefully along with other potential causes. An environmental medical assessment should include thorough medical history-taking and physical examination, the formulation of a differential diagnosis, and (whenever indicated) human biomonitoring, site inspections, and ambient monitoring. METHODS: This review of clinically relevant environment-related health disturbances is based on a selective evaluation of the pertinent literature and of own experiences. RESULTS: Overall, relevant environmental exposures can be identified in up to 15% of patients who attribute their health complaints to environmental factors. (Clinical disorders are more common and more severe in these patients.) 40% to 75% are found to suffer from other physical and/or emotional conditions without any specific environmental aspect, i.e., without any apparent or verifiable exposure. DISCUSSION: Despite the relative rarity of verifiable environmentally related health disturbances, these must be clearly identified and delimited to avoid further harmful exposures. Environmental medical counseling should include risk assessment and behavior recommendations for all patients who attribute their medical problems to their environment. Physicians performing specific environmental-medical diagnostic procedures must be aware of their limitations in order to avoid performing tests whose results have no therapeutic consequences and are thus of no help to either the physician or the patient.

Environmental factors as delusional contents in patients with schizophrenia.

In a series of 50 consecutive cases in the outpatients' unit of Environmental Medicine (UEM) at the University Hospital of Aachen, Germany, five patients with the diagnosis of schizophrenia presented delusions of being poisoned by environmental factors. This case report illustrates the clinical features of the paranoid type of schizophrenic psychoses. Schizophrenia represents an important differential diagnosis in the interdisciplinary diagnosis and management of health problems attributed to environmental factors.

Applicability of a set of diagnostic tests in indoor air health research.

Following recommendations from literature, 22 diagnostic tests for the most frequent complaints of indoor air health problems were selected and assessed for their applicability in epidemiological studies. The tests were applied seven times during one year to 40 volunteers who to all appearances were not affected by indoor air health problems. Most psychophysical tests (e.g., Continuous Performance Test) turned out to be suitable, but physiological tests were either heavily disturbed by technical problems (e.g., portable electrogastrography), or biased by application techniques (e.g., acoustic rhinometry), or were simply too time-consuming (e.g., PC-based voice analysis). Hence, as standardized measurements and quantitative diagnostic tests in epidemiological indoor air health research may contribute to a better understanding of cause-effect relationships and yield new approaches for preventive and therapeutic strategies, more research is urgently needed to develop and evaluate suitable physiological tests and functional measurements.

Working memory deficiencies in adults associated with low-level lead exposure: implications of neuropsychological test results.

BACKGROUND: Although lead exposure has steadily decreased in the last few years, some lead is still used in the metal processing industry, mostly for wall paints and plumbing. Recent studies on children showed neurobehavioral effects of low-level exposure, but little is known about the neurocognitive effects of lead concentrations in the upper reference range on adults. METHODS: The neuropsychological effects of lead exposure were examined in 39 adult outpatients at the Unit of Environmental Medicine (UEM), University Hospital, Aachen, Germany. All patients underwent a comprehensive medical examination, including psychiatric. Venous blood and urine samples were collected and tested for heavy metals and selenium. Since the neuropsychological examination was not expected to reveal any severe abnormalities, only specific attentiveness functions were analyzed (alertness, working memory, flexibility, intermodal comparison) since these areas were the likeliest to show objectifiable effects. The tests were conducted using a standardized computerized battery. RESULTS: Lead blood levels ranged from 1 to 65.6 microg/l (mean 27.4 +/- 16.2 microg/l). Although the neuropsychological test results of all patients were within the normal range, there were significant correlations between blood lead levels and the speed of information processing for working memory. CONCLUSIONS: The results indicate working memory dysfunctions in adults, the severity of which correlates directly with blood lead levels, supporting the hypothesis that increased blood lead levels can also be associated with measurable neurocognitive abnormalities.

Communication problems with environment-related health disorders as illustrated by a multiple chemical sensitivity (MCS) chatroom.

The problem of communication in treating multiple chemical sensitivity (MCS) was analysed and evaluated using the documentation of an MCS chatroom which was set up in April 2001 following the TV programme Gesundheitsmagazin Praxis (Health Magazine: Practice). Approaches were developed for solving communication problems in the chatroom. A total of 490 cases were evaluated, most of which (355) were directly or indirectly affected, 76 came from self-help groups and 10 were from 4 guest experts invited by ZDF (Zweites Deutsches Fernsehen, Second German TV channel). Of these 4 experts, 2 were environmental medicine specialists, 1 psychosomatics expert and 1 psychiatrist. Fourty-nine of the cases included a petition for chatroom participants to join a class-action law. Aside from exchanging basic information on MCS, frequent topics of discussion on the air were the assessment of physicians, clinics, self-help groups and experts. The participants also expressed their views on problems with society, politics, the economy, science and social security. Another common topic was communication in the chatroom itself, which for the most part consisted of sarcasm and insults, which were cause for conflicts in the chatroom. These communication problems led to the conclusion that a chatroom is not the best medium for discussing MCS. If a chatroom is to be used profitably to this end, it is imperative to have a well-defined organisational framework which allows the exchange of current, scientifically accurate information while keeping discussions from escalating and degenerating into arguments.

Environmental agents as cause of health disorders in children presented at an outpatient unit of environmental medicine.

There are no publications on the frequency of environmental agents causing diseases in children presented at centers of environmental medicine. The aim of this study was to perform a statistical analysis of the data of children who visited the outpatient Unit of Environmental Medicine (UEM) at the University Hospital of Aachen, Germany. Data of all UEM patient files from January 1988 to September 1996 were evaluated. From a total of 682 patients, 75 were children (40 girls, 35 boys, age range 1-12 years). Forty-six children were presented with unspecific health disorders, 12 to examine a possible relationship between environmental agents and a current condition, mostly atopy (n = 10). Complaints were mucosal irritations (n = 38), unspecific (n = 19), dermatological (n = 16), gastrointestinal (n = 4), heart/circulation-related (n = 2), musculoskeletal (n = 1) and neurological (n = 1) symptoms. Wood preservatives were mentioned as suspected environmental causative agents in 22 cases, followed by unspecific indoor factors (n = 15), factories/disposal sites near homes (n = 9), formaldehyde (n = 5) and unspecific exposures (n = 5). Biomonitoring was done in 44 cases, local inspections and ambient monitoring in 10 cases. No evidence for a cause-and-effect relationship was found in 55 children, but was deemed possible in nine cases. In nine other children, a relatively high degree of exposure was determined by chemical analysis, but clinical relevance remained unclear. One child suffered from subclinical mercury poisoning caused by inadequate homeopathic medication. In most children referred to an environmental medicine center, it is difficult or impossible to verify an environmental cause using the diagnostic instruments currently available.

Predictive value of human biomonitoring in environmental medicine: experiences at the outpatient unit of environmental medicine (UEM) of the University Hospital Aachen, Germany.

There is little data on the distribution of biomonitoring parameters in patients at outpatient Units of Environmental Medicine (UEM). We evaluated the biomonitoring parameters of 646 UEM outpatients from our University Hospital 1988-1998. Few patients were exposed to specific substances. Data of patients who were not obviously exposed was analysed statistically (geometric mean, standard deviation, median, 95th percentile). Results were compared with reference values in literature. Normal distribution of biomonitoring parameters was rare. 95th percentiles for arsenic, chromium, selenium, zinc, phenol and toluene were below standard, 95th percentiles for copper and mercury above, and 95th percentiles for lead, cadmium, pentachlorophenol, lindane, and beta-hexachlorocyclohexane were within the published range of reference values. Thallium as well as most volatile organic compounds analyzed were below detection levels. Aluminum and fluorine exposure was rarely analysed. In view of these results, it is concluded that the indication for biomonitoring needs to be stringent as levels of biomonitoring parameters are generally not risen in patients of the UEM.