Renewable toxicity

American Society for Testing and Materials (ASTM). Standard guide for conducting three-brood, renewal toxicity tests with Ceriodaphnia dubia. In Annual Book of ASTM Standards ASTM Philadelphia, 1989 Vol. 11.04, 360-379. 

ASTM. 1989b. Standard Guide for Conducting Three-Brood, Renewal Toxicity Tests with Ceriodaphnia dubia. El 295-89, American Society for Testing and Materials, Philadelphia, PA. 

What differences are there between a static and a static-renewal toxicity test ... 

Conducting Static Toxicity Tests with the Lemma gibba G3 Conducting a Terrestrial Soil-Core Microcosm Test Conducting Three-Brood, Renewal Toxicity Tests With Ceriodaphnia dubia Hazard of a Material to Aquatic Organisms and Their Uses... 

Closely related to the D. magna partial life-cycle toxicity test is the three-brood renewal toxicity test with Ceriodaphnia dubia (Table 4.3). The test was developed in an attempt to shorten the amount of time, amount of toxicant, and the cost of performing chronic type toxicity tests. This methodology has... 

Summary for Conducting Three-Brood, Renewal Toxicity Tests with Ceriodaphnia dubia... 

Why is the three-brood renewal toxicity test with Ceriodaphnia dubia used ... 

Toxicity Bioassay. Ninety-six hour acute toxicity tests were conducted on the effluent streams of major industries. A static renewal procedure was used in which waste waters of various dilutions were renewed at 24 hour intervals over a 96 hour period. Rainbow trout was used as the test organism. Tests were conducted at 13°C in 20 liter aquaria according to standard procedures (22), Results are summarized in Table 8. Chemical and toxicity test results indicate that the trace element quantities identified in Table 8 are not acutely toxic under the prevailing conditions and unlikely to pose an acute threat to aquatic life. In this case a chronic toxicity assessment would require additional research. 

The discovery that, in industrialised societies, diets deficient in fruits and vegetables can effectively double the risk of developing many different types of cancer has focused renewed attention on the beneficial properties of these foods (Block e/a/., 1992 Patterson ef a/., 1990 Southon and Faulks, 2002). As we have seen, plant foods are rich in micronutrients, but they also contain an immense variety of biologically active secondary metabolites providing colour, flavour and natural toxicity to pests and sometimes humans (Johnson et ah, 1994). The chemistry and classification of such substances is still a matter for much research and debate, but this has not prevented attempts to isolate and exploit substances that have variously been termed protective factors , phytoprotectants , phytochemicals and nutraceuticals . Phytochemical compounds include ... 

These batch procedures for enrichment and successive transfer may be replaced by the use of continuous culture. This may be particularly attractive when the test compound is toxic, when it is poorly soluble in water, or where the investigations are directed to substrate concentrations so low that clearly visible growth is not to be expected. These problems remain, however, for subsequent isolation of the relevant organisms. One considerable problem in long-term use arises from growth in the tubing of the pump system that is used to administer the medium and should be renewed periodically. 

Inherent hazard (e.g., toxicity, stability, reactivity) Cost Renewability Recyclability Size (volume) Scalability Controllability Energy (i.e., total, heating, cooling, recovery, treatment, etc.) Ease of cleaning and maintenance Safety/process safety ... 

For each chemical class, a set of 4-7 key attributes were identified that can be used to differentiate a chemical from others in the same class. These may include biodegradability, aquatic toxicity, sensitization potential, renewable resource derived, and so forth. Each attribute was selected to be ... 

Safety and risk factors evaluate approximately the speed at which a toxic substance reaches a toxic vapour concentration in air. An accurate way to do this would be to know the vapourisation speed for this substance and the air renewal rate of the room in which it is handled. This is why regulations recommend measurement of the vapourisation speed for a particular substance and include it in safety sheets. One can hardly use this figure since it is rarely mentioned. The only substances which were subjected to such measurements are the most commonly used although these figures only are remotely linked to the real conditions. So it was decided to suggest a method derived from the vapour pressure of the substance, which is a factor the vapourisation speed depends on precisely. 

Biodiesel is a fuel derived from renewable natural resources such as soybean and rapeseed and consists of alkyl esters derived from transesterification of triglycerides with methanol. In spite of all the advantages of biodiesel, such as low emissiotts, biodegradability, non-toxicity, and lubricity, the major hurdle in penetration of biodiesel is its high cost because of the expensive food grade refined vegetable oil feedstock. 

A tested product is allocated into one of four product classes based on its intended use. The more intensively a product comes into contact with the skin, the stricter the human toxicity requirement must be fulfilled by the product. A certificate is issued and will be valid for 1 year and can be renewed. 

In addition, it must be underlined that the chemical routes to cell-based materials are intrinsically green reactions because they imply that the viability of the living organisms is maintained. They should therefore be performed in mild temperature conditions and avoid the presence of cytotoxic products (or at least at non-toxic dose). Moreover, they use living cells that can be considered from a chemical reactivity point of view, as bio-renewable reagents. Such approaches can therefore be considered as the first steps towards the development of a green nanochemistry. 

Hence, with this background, there is an urgent need to develop renewable source-based environmentally benign polymeric materials (biopolymers [2]). Such materials would not involve the use of toxic or noxious components in their manufacture, and could be naturally degraded by composting. 

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