Motor neuron disease mortality rates in U.S. states are associated with well water use.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease with an unknown cause and invariably fatal outcome. We sought to evaluate a correlation between motor neuron disease (MND) mortality rates and residential radon levels that was previously reported for counties in the United Kingdom. We examined the relationships between age-adjusted MND mortality rates in U.S. states with residential radon levels, well water use, and other variables using structural equation modeling. We observed a significant correlation between MND mortality rates and radon levels. However, in structural equation models, radon did not have a significant, direct effect on MND mortality rates. Conversely, MND mortality rates were significantly and directly predicted by race and by the percentage of the population of each state using well water (p < 0.001 and p = 0.022). We observed similar, significant effects for well water use and MND mortality for males and females separately (p < 0.05). In conclusion, we hypothesize that the association of MND mortality rates with well water use reflects contamination of wells with Legionella, a bacterium common in well water that is known to cause neurologic disease. A Legionella hypothesis is a biologically plausible cause of ALS and suggests new avenues for etiologic research.

Riesgo ecotoxicológico acuático y terrestre del bioplaguicida catahua, Hura crepitans (Euphorbiaceae) / Ecotoxicological aquatic and terrestrial risk of biopesticide sandbox tree, Hura crepitans (Euphorbiaceae)

Hura crepitans (catahua) Linnaeus (Euphorbiaceae) es una planta nativa de América. El objetivo del presente trabajo fue evaluar el riesgo ecotoxicológico (REA) del bioplaguicida H. crepitans. Se determinaron los valores de toxicidad de la catahua para 42 puntos finales de efecto en 30 especies acuáticas y terrestres. Los valores de toxicidad (CL(E/I)50, NOEC o LOEC) obtenidos para las especies acuáticas y terrestres fueron comparados con la dosis promedio de aplicación de catahua en extracto acuoso para plagas del algodón (30000 mg i.a L-1), observándose que a esta concentración ocasionaría un riesgo en todas las especies acuáticas (100%) y en 16 especies terrestres (88,88%). Con un segundo procedimiento para la determinación del REA, se tomaron los valores de CL50 a 48 h de la larva de Spodoptera frugiperda, plaga en los cultivos de maíz y caña de azúcar, y se contrastó con los niveles de toxicidad para las especies acuáticas y terrestres no destinatarias, observándose riesgo sobre cuatro especies acuáticas (50%) (Daphnia magna, Chironomus calligraphus, Isochrysis galbana y Paracheirodon innesi), y sobre cinco especies terrestres (27,77%) (Apis mellifera, Orius insidiosus, Eisenia foetida, Trichogramma cacoeciae y Chrysoperla asoralis). Las saponinas y los flavonoides son los posibles grupos funcionales de importancia relacionados con la toxicidad de la catahua (AU)

Hura crepitans (catahua) Linnaeus (Euphorbiaceae) is a native plant of America. The aim of this study was to assess the ecotoxicological risk (REA) of the biopesticide H. crepitans. Values of sandbox toxicity for 42 endpoints on 30 aquatic and terrestrial species were determined. The toxicity values (LC(E/I)50, NOEC or LOEC) obtained for aquatic and terrestrial species were compared with the average application rate of sandbox aqueous extract for cotton pests (30000 mg i.a L-1), observed that this concentration would cause a risk to all aquatic species (100%) and 17 terrestrial species (94.44%). With a second method for determining the REA, the LC50 values at 48 h larva Spodoptera frugiperda, pest in corn and sugar cane were taken, and was compared with the levels of toxicity to non-target aquatic and terrestrial species, risk observed upon four aquatic species (50%) (Daphnia magna, Chironomus calligraphus, Isochrysis galbana y Paracheirodon innesi), and six terrestrial species (33.3%) (Apis mellifera, Orius insidiosus, Eisenia foetida, Trichogramma cacoeciae and Chrysoperla asoralis). Saponins and flavonoids are the possible functional groups of importance regarding sandbox toxicity (AU)

Identification of primary polydipsia in a severe and persistent mental illness outpatient population: a prospective observational study.

Studies to date have only investigated primary polydipsia in hospitalized psychiatric patient populations, where rates range from 3% to 25%. The objective of the present study was to determine the occurrence of primary polydipsia in a psychiatric outpatient population, and to determine the perceptions of outpatients with self-induced water intoxication regarding reasons for drinking excess fluids, health risks, and insight into their behavior. All 115 psychiatric outpatients from a Community Outreach Program in Kingston, Ontario, were invited to participate in this study. Of these, 89 (77.4%) were enrolled. Data collection included chart reviews, structured interviews, weight measurements, and urine collection. The incidence of primary polydipsia was found to be 15.7%. One-half of the polydipsic people presenting with medical complications suggestive for water intoxication had cigarette smoking as a strong correlate. There were interesting answers to the self-induced water intoxication questionnaire. These showed a lack of knowledge related to the normal quantity of fluids necessary daily and about healthy behaviors. Excessive drinking occurs in psychiatric patient populations outside of institutional/hospital settings. Patients have limited awareness of the severity and possible complications from their problem. Given the prevalence of polydipsia, more effort should be put into identifying and treating this problem.

Trihalometanos en aguas de consumo humano / Trihalomethanes in water supply

Los trihalometanos (THMs) son subproductos de desinfección que resultan de la cloración de las aguas. Los THMs engloban a sustancias como el cloroformo (CHCl ), el 3 bromodiclorometano (CHBrCl ), el clorodibromometano (CHBr Cl) 2 2 y el tribromometano (CHBr ). La Agencia Internacional para la 3 Investigación del Cáncer ha clasificado al cloroformo y al bromodiclorometano en el grupo 2B que incluye a las sustancias posiblemente carcinogénicas en humanos. Debido a su toxicidad y a que el agua de consumo humano constituye la principal vía de exposición del hombre a estos compuestos, su presencia en las aguas de consumo humano está limitada por la Directiva Europea 98/83/CE a 100 ìg/L. En esta revisión se destacan los aspectos más relevantes sobre su toxicidad, reglamentación, determinación, concentración en aguas, variaciones estacionales y eliminación (AU)

Trihalomethanes (THMs) are disinfection byproducts resulting from chlorination of water. THMs comprise substances such as chloroform (CHCl ), 3 bromodichloromethane (CHBrCl ), chlorodibromomethane 2 (CHBr Cl) and tribromomethane (CHBr ). The International Agency 2 3 for Research on Cancer has classified chloroform and bromodichloromethane in Group 2B, which includes potentially carcinogenic substances in humans. Because of its toxicity and that drinking water is the main human exposure to these compounds, their presence in drinking water is limited by the European Directive 98/83/EC to 100 mg/L. This review highlights the most relevant aspects of its toxicity, regulation, determination, concentration in water, and removing seasonal variations (AU)

Water intoxication-a dangerous condition in labor and delivery rooms.

Water intoxication, a form of acute hyponatremia, has been described in various clinical situations. Although hyponatremia is a common metabolic disorder in hospitalized patients, it is generally not well known as a hazard in the labor and delivery room. However, several factors predispose laboring women to develop hyponatremia. Moreover, because the fetus acquires water from the maternal circulation via the placenta, and there is a close correlation between maternal and cord blood serum sodium levels, the newborn infant of a hyponatremic mother is also at considerable risk of developing water intoxication. We review the epidemiology, pathophysiology, clinical features, and treatment of this hazardous disorder. We emphasize the need for awareness of this condition, and call attention to the risk of fluid overload during labor.

Schizophrenic patients with polydipsia and water intoxication more often have a form of schizophrenia first described by Kraepelin.

Polydipsia and water intoxication (PWI) seem to be associated with a particular form of schizophrenia, first described by Kraepelin, involving negative symptoms, disorganization and poor outcome. In this study, a group of 20 schizophrenic patients with PWI was selected and matched for age, duration of illness and gender with a group of 20 schizophrenic controls with no PWI. For these patients the following measure were obtained: clinical and demographic data, Keefe's criteria for Kraepelinian schizophrenia, the Positive and Negative Syndrome Scale score and the score on Fagerström's Nicotine Dependence Scale. The group of schizophrenic patients with PWI presents significantly higher levels of negative symptoms, disorganized symptoms and general symptoms of psychopathology, and it is composed of a significantly higher percentage of Kraepelinian patients. These results show an association of polydipsia and water intoxication with Kraepelinian schizophrenia suggesting physiological hypotheses for a specific pathogenic pathway.

Polydipsia--a study in a long-term psychiatric unit.

This is a retrospective review of the author's experience with polydipsia in a long-term unit for treatment refractory patients at a US psychiatric state hospital during a 5-year period [1996-2000]. Sixty-one patients were admitted to this long-term unit, comprising approximately 1 % of the hospital admissions. Polydipsic patients were followed with diurnal weight changes and other biological measures. This longitudinal study of 61 chronic inpatients suggests that polydipsia is no doubt present in at least 20 % of chronic psychiatric inpatients and hyponatremia in more than 10 %. Two polydipsic patients worsened when switched from clozapine to other atypical antipsychotics. Polydipsia in severe mentally ill patients continues to be a neglected subject and a challenge for psychiatrists. Polydipsic patients should not be switched to other atypical antipsychotics, unless new prospective studies prove that they are as effective as clozapine for polydipsia.

Polydipsia and schizophrenia in a psychiatric hospital: a replication study.

A prior study in a US state hospital suggested that schizophrenia, smoking and long hospitalization were associated with polydipsia. This study, in another US hospital, attempts to (1) replicate that schizophrenia and smoking are associated with polydipsia, and (2) rule out that this relationship is partly explained by alcohol and drug use. Both studies have similar methodologies. The second sample included 588 inpatients. Models of variables associated with polydipsia were developed using logistic regression. In the second study, after correcting for other factors, the association between polydipsia and schizophrenia showed a borderline significance, while polydipsia and smoking displayed a significant association. Neither organic brain lesions, nor alcohol or drug use, were associated with polydipsia. An analysis combining both samples showed that: (1) schizophrenia, long hospitalization, smoking and heavy smoking were significantly associated with polydipsia, and (2) male gender and Caucasian race (but not smoking) increased the risk of developing water intoxication in polydipsic patients. These two studies in severely mentally ill patients suggest that the association of polydipsia with schizophrenia, smoking and chronicity is consistent and independent from the definition of polydipsia (by staff, a biological method or the combination of both). Psychiatric medications do not appear to explain most cases of polydipsia in these patients.

[Prevalence of polydipsia and water intoxication in psychiatric inpatients]. / Prevalencia de polidipsia e intoxicación por agua en pacientes psiquiátricos hospitalizados.

INTRODUCTION: The prevalence of polydipsia and water intoxication among psychiatric inpatients has been described in different countries, however few studies have been conducted in Europe. The present study was aimed at evaluating the prevalence of polydipsia and water intoxication in an European Psychiatric Hospital. METHODS: SPGU (Specific Gravity of Urine) and Normalised Diurnal Weight Gain (NDWG) were evaluated among 201 inpatients. RESULTS: Risk of polydipsia and water intoxication were found among 51% of all patients. Risk of primary polydipsia was present in 25% of patients, and primary polydipsia and risk of water intoxication among 25% of all patients. CONCLUSIONS: This is one of the unique studies of polydipsia and water intoxication in psychiatric inpatients in Europe, and the first one conducted in Spain. The development of specific preventative and clinical programmes in psychiatric patients is suggested due to the clinical relevance and high prevalence of this pathology.

Polydipsia and water intoxication in 353 psychiatric inpatients: an epidemiological and psychopathological study.

INTRODUCTION: According to several authors, water intoxication can lead to irreversible brain damage and could be the cause of nearly a fifth of the deaths of schizophrenic patients below the age of 53 years. The aim of our study was first to determine the prevalence of polydipsia and water intoxication in a population of psychiatric inpatients of a well-defined French geographic area (the Somme), and secondly to determine the clinical and socio-demographic factors associated with this disorder. METHOD: A cross-sectional survey was done on the 450 psychiatric beds whose catchment area had a total population of 559,429 inhabitants. Using staff reports and patients' charts, the drinking habits of 353 psychiatric inpatients hospitalised during the survey in the 450 psychiatric beds of this area were examined. RESULTS: Thirty-eight patients (10.76%; 95% confidence interval: 7.53-13.99%) among the 353 inpatients were polydipsic. About one-third of these patients were at risk of water intoxication. Polydipsia appeared to be significantly associated with male gender, smoking, celibacy and chronicity. The polydipsic patients presented also a high prevalence of schizophrenia, mental retardation, pervasive developmental disorders and high frequency of somatic disorders.

Hyponatremic seizures secondary to oral water intoxication in infancy: association with commercial bottled drinking water.

In recent years, hyponatremic seizures resulting from water intoxication have been reported in the United States with an increasing frequency that some have likened to an epidemic. Infants of parents living in poverty and uninformed of the risks of feeding fluids other than infant formula to their babies are particularly at risk. Young infants with vomiting and diarrhea are especially prone to developing hyponatremia if fed fluids lacking sufficient sodium, but even those who are otherwise well may develop symptomatic hyponatremia as a result of being fed excess solute-free water. Most often tap water, either in the form of supplemental feedings or overly dilute formula, has been given in excessive amounts over relatively short periods of time. Less frequently, water in other forms such as juice, soda, or tea has been implicated. This report includes the cases of two infants treated at our institution for hyponatremic seizures and water intoxication after being fed with the same bottled drinking water product marketed for use in infants. The medical records of all infants

Disordered water homeostasis in Asian patients with schizophrenia.

OBJECTIVE: The aim of this study was to determine the prevalence of polydipsia-hyponatremia among patients with schizophrenia in an Asian mental hospital. METHOD: Seven hundred and twenty-eight inpatients with schizophrenia were assessed for polydipsia-hyponatremia using case notes reviews, specific gravity of urine, normalised diurnal weight gain, and serum sodium levels. RESULTS: One hundred and three (13.8%) patients had polydipsia, 30 (4.1%) had polydipsia-hyponatremia and 14 (1.9%) had a history of water intoxication. Eight of the 30 patients were receiving carbamazepine, three were on tricyclic antidepressants and two had diabetes mellitus and were on sulfonylureas. CONCLUSION: The prevalence of water intoxication among polydipsic patients was low compared to Western studies. This could be due to different methods of assessing polyuria, or ethnic differences and/or the prohibition of smoking in our patients. Certain medications might have also contributed to hyponatremia.

A demographic study of polydipsia in an institution for the intellectually disabled.

OBJECTIVE: To measure the prevalence of primary polydipsia in an Ontario institution for residents with developmental disabilities and to explore the associations of polydipsia with age, sex and level of mental retardation. METHOD: All 798 residents were screened for polydipsia using a behavioural questionnaire completed by caregivers. RESULTS: Thirty-three cases were detected: the prevalence among the mobile resident population (n = 660) was 5%. We found no association of polydipsia with age, sex, or level of mental retardation. CONCLUSIONS: Physicians should be aware of polydipsia because it is common among residents with moderate, severe, and profound mental disability. Unless screened for specifically, polydipsia may go unrecognized and may place the residents with mental handicap at risk for serious acute and chronic complications.

Screening patients with mental retardation for polydipsia.

OBJECTIVES: To determine whether caregiver responses to a screening question are a reliable method of identifying polydipsia (excessive water drinking) in institutionalized residents with mental retardation. To review the etiology, acute and chronic clinical manifestations, and care of polydipsia and water intoxication. METHOD: This paper presents an assessment of interrater reliability for a screening question for polydipsia using responses of primary caregivers of preidentified polydipsia cases (n = 32) and matched controls (n = 33) in a large Canadian institution for developmentally handicapped adults. A chart review of all cases of identified water intoxication is also provided. The behavioural outcomes of preventive measures for water intoxication are described. RESULTS: The screening instrument was reliable, having a kappa (interrater reliability) of 0.73. Several case descriptions illustrate typical presentations of water intoxication in this population. CONCLUSIONS: Polydipsia is reliably identified by caregiver responses to a screening question. It should be screened for regularly to ensure appropriate care to prevent important acute and chronic complications.

Polydipsia and water intoxication in a long-term psychiatric hospital.

This cross-sectional survey attempts to establish the prevalence of polydipsia and water intoxication at a state hospital (N = 360) using staff diagnosis, specific gravity of the urine (SPGU), weight changes, and chart review. There were 150 [42%, 95% confidence interval (CI) 37-47%] patients diagnosed as polydipsic by the staff or by SPGU. At least 93 (26%, CI 21-30%) had primary polydipsia not explained by other causes. Chart review identified 17 (5%, CI 3-7%) patients with a history of water intoxication. Using a case-control study design, schizophrenia, extended duration of hospitalization, and heavy smoking were associated with primary polydipsia in a logistic regression analysis (respective odds ratios were 1.6, 1.8, and 3.6). All patients with a history of water intoxication were Caucasian (versus 83% in those without a history) and had significantly more extended hospitalizations (94 vs. 49%). Future case-control studies should combine longitudinal identification of true cases and controls and exhaustive collections of clinical information in a standardized way.

Polydipsia and water intoxication in psychiatric patients: a review of the epidemiological literature.

Polydipsia among chronic psychiatric patients is poorly understood and underdiagnosed. It may have three stages: simple polydipsia, polydipsia with water intoxication, and physical complications. Epidemiological surveys have used staff reports and polyuria measures to identify polydipsic patients. Water intoxication has been screened by chart review, weight, or serum sodium data. According to these surveys, polydipsia, not explained by medically induced polyuria, may be present in more than 20% of chronic inpatients. Up to 5% of chronic inpatients had episodes of water intoxication although mild cases may have been missed. Single time point surveys show that 29% of polydipsic patients had presented water intoxication. Methodologically limited clinical studies suggest that polydipsia with water intoxication rather than simple polydipsia may be associated with poor prognosis in schizophrenia. Epidemiological surveys found polydipsia with water intoxication to be associated with chronicity, schizophrenia, smoking, some medications, male gender, and white race. New pathophysiological models need to elucidate these findings.

Urinary arginine vasopressin (AVP) measurement in children: water deprivation test incorporating urinary AVP.

The value of a water deprivation test incorporating urinary arginine vasopressin (AVP) measurement was investigated in 13 patients with polydipsia and/or polyuria (complete central diabetes insipidus [CCDI] in four; incomplete central diabetes insipidus [ICDI] in five; secondary nephrogenic diabetes insipidus [NDI] in three; compulsive water drinking [CWD] in one) and a group of 25 control subjects (C). Urine samples were collected after water deprivation during sleep and the urinary osmolalities and AVP concentrations were measured. Analysis of the results of 104 urine samples from the 25 control subjects demonstrated a close correlation between urinary osmolality and AVP (r = 0.89, P < 0.001). After water deprivation during sleep, the respective mean maximal urinary osmolalities and AVP concentrations were: 127.4 +/- 34.4 mOsm/kg and 1.1 +/- 0.5 pg/mL in the patients with CCDI (14 samples, four children); 410.3 +/- 101.8 and 6.1 +/- 3.5 in those with ICDI (16 samples, five children); 348.7 +/- 71.2 and 100 +/- 45.1 in those with NDI (nine samples, three children); 541.5 +/- 143.5 and 43.6 +/- 33.2 in the patient with CWD (two samples, one child) and 898.8 +/- 186.3 and 97.4 +/- 50.4 in group C (54 samples, 18 children). Furthermore, the urinary AVP level relative to the osmolality in each patient varied depending on the AVP secretion status and renal concentrating ability. Each patient, except the one with CWD, could be discriminated from the normal subjects using this test. It seems that this test is easy to perform and useful for diagnosis and follow-up of patients with partial/complete posterior pituitary function defects and those with renal concentration impairment.