Bibliography: p. 283-284
Government Reference Publication
Excerpt: Poisonings by waterblooms of toxic cyanobacteria (cyanobacteria toxin poisonings; CTP) are a significant part of the concern over harmful algal blooms (1?4). The toxins, called cyanotoxins, are responsible for intermittent but repeated widespread poisonings of wild and domestic animals and aquacultured fish. Cyanotoxins include neurotoxic anatoxin-a and anatoxin-a(s), paralytic shellfish poisons (PSP; saxitoxin and analogues), and hepatotoxic microcystins, nodul...
Excerpt: Although the soil surface may look like dirt to you, it is full of living organisms that are a vital part of desert ecosystems. This veneer of life is called a biological soil crust. These crusts are found throughout the world, from hot deserts to polar regions. Crusts generally cover all soil spaces not occupied by green plants. In many areas, they comprise over 70% of the living ground cover and are key in reducing erosion, increasing water retention, and incr...
Medical Reference Publication
The term algae refers to microscopically small, unicellular organisms, some of which form colonies and thus reach sizes visible to the naked eye as minute green particles. These organisms are usually finely dispersed throughout the water and may cause considerable turbidity if they attain high densities. Cyanobacteria are organisms with some characteristics of bacteria and some of algae. They are similar to algae in size and, unlike other bacteria, they contain blue-gree...
In coastal and estuarine waters, algae range from single-celled forms to the seaweeds. Cyanobacteria are organisms with some characteristics of bacteria and some of algae. They are similar in size to the unicellular algae and, unlike other bacteria, contain blue-green or green pigments and are able to perform photosynthesis; thus, they are also termed blue-green algae. Algal blooms in the sea have occurred throughout recorded history but have been increasing during recen...
Foreword Concern about the effects of cyanobacteria on human health has grown in many countries in recent years for a variety of reasons. These include cases of poisoning attributed to toxic cyanobacteria and awareness of contamination of water sources (especially lakes) resulting in increased cyanobacterial growth. Cyanobacteria also continue to attract attention in part because of well-publicised incidents of animal poisoning. Outbreaks of human poisoning attributed to...
Excerpt: The occurrence of heavy freshwater blooms of cyanobacteria (blue-green algae) has been well reported in many parts of the world (1). Among the toxic blue-green algae, Microcystis is the most common genera producing microcystins, a group of toxins with strong hepatotoxicity (1,2). These toxins are able to cause the death of domestic and wild animals as well as human illness (3). Recently, it has been reported that dialysis patients in Brazil died of acute hepatic...
Excerpt: Synonyms Red tide toxins, phycotoxins Periodic blooms of algae, including true algae, dinoflagellates, and cyanobacteria or blue-green algae have been reported in marine and freshwater bodies throughout the world. Although many blooms are merely an aesthetic nuisance, some species of algae produce toxins that kill fish, shellfish, humans, livestock and wildlife. Pigmented blooms of toxinproducing marine algae are often referred to as “red tides” (Fig. 36.1). Pro...
Ehrlich put forward the idea that the objective of chemical ,attack upon noxious micro-organisms should be to interfere with the metabolic processes of the parasite in a specific manner, so that the host itself be uninjured. At the time Ehrlich proposed this, however, relatively little was known about those metabolic processes n-hich could be injured or about how they could be injured. The result v7as that, even with this guiding principle, there was little opportunity t...
The Committee took note of the extensive evidence for the genotoxicity of several members of this group of flavouring agents related to furan, including the clastogenicity of 2-furyl methyl ketone (No. 1503) in mouse bone marrow
INTRODUCTION The decomposition of organic molecules such as pesticides and polymers is known to occur under- the influence of a variety of agents, e.g. heat, oxygen, light, water, ionizing radiation, biological organisms, mechanical forces and numer.ous chemical reagents. The tern) degradation is generally applied to such decompositions, since they generally lead to a reduction and/or destrucrion of the original useful properties. Degradation may occur relatively slowly ...
Polycyclic aromatic hydrocarbons (PAHs) constitute a large class of organic compounds containing two or more fused aromatic rings. Hundreds of individual PAHs may be formed during incomplete combustion or pyrolysis of organic matter, industrial processes and cooking and food processing
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The complex interconnectedness of freshwater systems demands that freshwater management be holistic (taking a catchment management approach) and based on a balanced consideration of the needs of people and the environment. The Mar del Plata Action Plan has already recognised the intrinsic linkage between water resource development projects and their significant physical, chemical, biological, health and socioeconomic repercussions” The approaches and methods for water qu...
2.1 Introduction Quality assurance is an important feature of all analytical work and it comprises several features that are common to all chemical analyses. In the present text, emphasis is on the features, and especially sources of error, that are more or less specific to biological monitoring (in contrast to e.g. clinical chemistry and toxicology), such as contamination, importance of the timing of sample collection or need for international collaboration in external ...
1. | INTRODUCTION Herbal and other traditional pharmacologic therapies are in widespread use throughout the world. Such widespread use suggests, but does not assure, that traditional medicines have a favourable risk-benefit ratio. Rather, traditional medicines may be regarded as a rich source of potentially attractive therapies. The actual benefits and risks remain to be evaluated by clinical trials supported and conducted according to the principles of modern clinical science.
The efficiency of the Ziehl-Neelsen method for staining acid-fast bacteria was compared with that of the strip-stainingprocedure in which one kind of impregnated strip is used to stain the bacteria and another kind for simultaneous decolorization and counterstaining of the smear. The methods were evaluated in I 136 duplicate smearsprepared from digested sputum and 307 pairs of direct smears. The efficiency of the strip method was comparable to that of the Ziehl-Neelsen m...
I. Introduction and oarticipation 1. The Fifth Intersecretariat ?feetingz on Air Pollution Problems in Europe convened by the WiO Regional Office for Europe, took place on 11 September 1981 at the Palais d e ~Na tions in Geneva. 2. I: was attended by representatives of the following international and ince~governmental agencies: Inccmarional Labour Officc (ILO), United Nations Economfc Commission for Europe (IJXECZ), Gniced ?lacions Development Programme (UNDP), World Hea...