Controlling Legionella pneumophila in water systems at reduced hot water temperatures with copper and silver ionization

Background: Hospital-acquired Legionnaires’ disease is associated with the presence of Legionella pneumophila in hospital water systems. In the United Kingdom, the Department of Health recommends maintaining hot water temperatures >55°C and cold water temperatures <20°C at the point of delivery to prevent proliferation of L pneumophila in water systems. In this study, we evaluated the efficacy of copper and silver ionization to control L pneumophila at deliberately reduced hot water temperatures (43°C) within a newly installed water system in a new building linked to a large health care facility in the United Kingdom. / Methods: One thousand, five hundred ninety-eight water samples were collected between September 2011 and June 2017. Samples were tested using accredited methods for L pneumophila, copper and silver ion levels, and total viable counts. Energy consumption and water usage data were also collected to permit carbon emission calculations. / Results: The results of 1,598 routine samples from September 2011 to June 2017, and the recordings of temperatures at outlets in this facility, demonstrated effective (100%) L pneumophila control throughout the study period with an average hot water temperature of 42°C. The energy savings and reduction of carbon emissions were calculated to amount to 33% and 24%, respectively, compared to an equivalent temperature-controlled system. Water system management interventions were required to achieve consistently adequate levels of copper and silver across outlets. / Conclusions: This study demonstrated that it is possible to control L pneumophila independent of temperature when copper and silver ionization is introduced into a new building in conjunction with an appropriately managed water system

Effects of Environmental Agents on the Attainment of Puberty: Considerations When Assessing Exposure to Environmental Chemicals in the National Children’s Study

The apparent decline in the age at puberty in the United States raises a general level of concern because of the potential clinical and social consequences of such an event. Nutritional status, genetic predisposition (race/ethnicity), and environmental chemicals are associated with altered age at puberty. The Exposure to Chemical Agents Working Group of the National Children’s Study (NCS) presents an approach to assess exposure for chemicals that may affect the age of maturity in children. The process involves conducting the assessment by life stages (i.e., in utero, postnatal, peripubertal), adopting a general categorization of the environmental chemicals by biologic persistence, and collecting and storing biologic specimens that are most likely to yield meaningful information. The analysis of environmental samples and use of questionnaire data are essential in the assessment of chemicals that cannot be measured in biologic specimens, and they can assist in the evaluation of exposure to nonpersistent chemicals. Food and dietary data may be used to determine the extent to which nutrients and chemicals from this pathway contribute to the variance in the timing of puberty. Additional research is necessary in several of these areas and is ongoing. The NCS is uniquely poised to evaluate the effects of environmental chemicals on the age at puberty, and the above approach will allow the NCS to accomplish this task

Exposure Assessment in the National Children’s Study: Introduction

The science of exposure assessment is relatively new and evolving rapidly with the advancement of sophisticated methods for specific measurements at the picogram per gram level or lower in a variety of environmental and biologic matrices. Without this measurement capability, environmental health studies rely on questionnaires or other indirect means as the primary method to assess individual exposures. Although we use indirect methods, they are seldom used as stand-alone tools. Analyses of environmental and biologic samples have allowed us to get more precise data on exposure pathways, from sources to concentrations, to routes, to exposure, to doses. They also often allow a better estimation of the absorbed dose and its relation to potential adverse health outcomes in individuals and in populations. Here, we make note of various environmental agents and how best to assess exposure to them in the National Children’s Study—a longitudinal epidemiologic study of children’s health. Criteria for the analytical method of choice are discussed with particular emphasis on the need for long-term quality control and quality assurance measures

Some recent rural radio talks

Cream stirring is important. - D.C. Mickle Crossbreeding in pig production. - P. Beck Salmonella infection in sheep. - I.J. Miller Useful sprays for the home garden. A.A. Holland Tapeworm of dogs and cats. P.B. Lewis The poison plant and the animal. - R.D. Royce Sire surveys to prove bulls. K. Needham Peat as a substitute for horse manure. - L.T. Jone