Laboratory & Water Quality
Guidelines For Drinking-Water Quality Management For New Zealand Chapter 7: Virological Compliance
Introduction :
There are more than 140 different types of human enteric viruses that may contaminate potable source waters. These include several important groups: Hepatitis A virus, Hepatitis E virus, norovirus, enterovirus and adenovirus, that have been associated with waterborne illness and are capable of causing severe, and in some cases fatal, infections. Individual datasheets have been prepared for the more important viruses.
Viruses are obligate intracellular parasites, which means they cannot grow or multiply outside their host. Viruses simply consist of a nucleic acid genome (either ribonucleic acid [RNA] or deoxyribonucleic acid [DNA]) surrounded by a protein capsid and, in some cases, a lipoprotein envelope. These viruses are very small, ranging from 20–80 nm (0.02–0.08 micrometres) in diameter; see Figure 4.2 in Chapter 4 to gain a perspective of their size.
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Introduction
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Rapid Assessment of Drinking Water Quality
Introduction
The provision of water was one of the eight components of primary health care identified by the World Health Assembly in Alma Ata in 1978. The Alma Ata Declaration on Primary Health Care expanded the concept of health care to include broader concepts of affordability, accessibility, self-reliance, inter-sectoral collaboration, community participation, sustainability and social justice. The importance of water supply continues to be emphasised as critical to reducing poverty and improving the health and well-being of the World's children and adults. The global community has committed itself to halving the proportion of the world's population who are unable to reach or to afford safe drinking water by 2015. Although great strides have been made in meeting this challenge in terms of provision of services, the safety of many water supplies remains unknown and uncertain. The recent Global Water Supply and Sanitation Assessment 2000 Report provided statistics regarding access to technologies that were either 'improved' or 'unimproved'. This was done on the assumption that some technologies were likely to be better for health, although it was recognised that would not always be the case. However, there was no information provided on water quality within the assessment. The inclusion of information regarding water quality in future assessments of the degree of access to water supplies is desirable. This handbook is designed to help in the implementation of rapid assessments of water quality to improve the knowledge and understanding of the level of safety of water supplies. There is significant value in reporting of independently verifiable water quality data to support national Governments and the international community in measuring progress in achieving the international development targets. Such data provides useful information regarding current conditions, deriving the likely public health burden relate to inadequate water supply and to gain an understanding of the extent of major water quality problems in developing countries. These data would, therefore, provide an indication of future investment priorities and needs on a country, regional and global basis.
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Abstract
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Abstract
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A Manual On Water Quality Treatment Methods At Community And Household Level
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About this book :
This book is a compilation work of various techniques adopted at different parts of the world for removal of a range of chemical parameters which are present beyond the permissible limit in drinking water. The different technologies those are described in this book are mainly limited to household level and for community level. The stepwise pictorial presentation for treatment of contaminated water to remove different chemical parameters and biological treatment will possibly be appreciated by the readers of this book. The authors of this book have tried their best, put their utmost thought and taken maximum care while compiling the available information so that this piece of work will be accepted by every individual. This book in general comprises three sections and eight chapters are within these sections. Section-I comprises only one chapter which describes different water quality problems in India with specific interest to Odisha and for whom this book is designed. Similarly, the section-II encompasses four chapters. Water quality standards, water quality occurrence in different parts of the state and its presentation in shape of a map are reflected in these chapters. Section –III, which is the most important section of this book, illustrates identification of problems and their mitigation measures at household level as well as at community level. Material quantification and maintenance procedures are also depicted in this section.
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Introduction:
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Analysis of Wastewater for Use in Agriculture – A Laboratory Manual of Parasitological and Bacteriological Techniques
Introduction:
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