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Species harmful

Van Wambeke F (1994) Influence of phytoplankton lysis or grazing on bacterial metabolism and trophic relationships. Microb Ecol 27 143-158 Veldhuis MJW, Brussaard CPD, Noordeloos AAM (2005) Living in a Phaeocystis colony a way to be a successful algal species. Harmful Algae 4 841-858 Verity PG, Medlin LK (2003) Observations on colony formation by the cosmopolitan phytoplankton genus Phaeocystis. J Mar Syst 43 153-164 Weinbauer MG (2004) Ecology of prokaryotic viruses. FEMS Microbiol Rev 28 127-181... [Pg.216]

To "take" is to harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect a plant or animal of any threatened or endangered species. Harm includes significant habitat modification when it kills or injures a member of a listed species through impairment of essential behavior (e.g., nesting or reproduction). For any non-federal industrial activity, the burden is on the owner or operator to determine if an incidental take permit is needed. This is typically accomplished by contacting the U.S. Fish and Wildlife Service (FWS) to determine whether any listed species are present or will potentially inhabit the project site. A biological survey may be required to determine whether protected species are present on the site and whether... [Pg.247]

The abihty to perform oxidations without generating species harmful for potential intermediates of further transformations is important to perform multistep synthesis, such as the domino reactions described below (Section 5). In this respect, the use of aryl hahdes as readily available, stable and cheap oxidants (hydride acceptors) is a powerful option due to the production of inert, dehalogenated aryl by-products in anaerobic conditions. Commercially available Pd and Ni complexes with NHC ligands were found to be active in a temperature-controlled domino oxidation/R-ketone arylation with aryl halide. ... [Pg.111]

The threat of accidental misuse of quaternary ammonium compounds coupled with potential harmful effects to sensitive species of fish and invertebrates has prompted some concern. Industry has responded with an effort to replace the questionable compounds with those of a more environmentally friendly nature. Newer classes of quaternaries, eg, esters (206) and betaine esters (207), have been developed. These materials are more readily biodegraded. The mechanisms of antimicrobial activity and hydrolysis of these compounds have been studied (207). AppHcations as surface disinfectants, antimicrobials, and in vitro microbiocidals have also been reported. Examples of ester-type quaternaries are shown in Figure 1. [Pg.379]

Environmental. The toxicity of cyanide in the aquatic environment or natural waters is a result of free cyanide, ie, as HCN and CN . These forms, rather than complexed forms such as iron cyanides, determine the lethal toxicity to fish. Complexed cyanides may revert to free cyanide under uv radiation, but the rate is too slow to be a significant toxicity factor. Much work has been done to estabhsh stream and effluent limits for cyanide to avoid harmful effects on aquatic life. Fish are extremely sensitive to cyanide, and the many tests indicate that a free cyanide stream concentration of 0.05 mg/L is acceptable (46), but some species are sensitive to even lower concentrations. [Pg.380]

Finally, there are also pollutants that do not cause direct health impacts hut that may have the potential to cause harm indirectly, through their actions on the overall ecology, or as they function as precursor chemicals that lead to the production of other harmful chemicals. The major indirect-action pollutants include volatile organic carbon (VOC) compounds that act as precursors to more harmful species chemicals called halocarbons and chemicals called greenhouse gases. [Pg.48]

Materials selection cannot be based on any simple combination of common corrosive species. There are many complicating factors, including the harmful or beneficial effects of contaminants at the ppm level, the relative proportion in which certain combinations of species are present (H+ and CH are often synergistic in their effect, whereas and CH often counter each other) and the... [Pg.899]

The chief advantage of wood for containers is that many common species are free from harmful contaminants. For this reason wood had widespread use in the food and beverage industries, but it has now suffered severe competition from corrosion-resistant metals, plastics and paper products. Oak had a very extensive use in tight cooperage in the brewing industry, and its use for barrels still survives in the maturing of whisky and brandy and in the wine industries. Wood is particularly useful where acetic acid is present as this acid is corrosive to most common metals. [Pg.963]

The harmful effects of radiation result from its high energy, sufficient to form unstable free radicals (species containing unpaired electrons) such as... [Pg.528]

Apart from gastropods, harmful effects of TBT have also been demonstrated in oysters (Environmental Health Criteria 116, Thain and Waldock 1986). Early work established that adult Pacific oysters (Crassostrea gigas) showed shell thickening caused by the development of gel centers when exposed to 0.2 pg/L of TBT fluoride (Alzieu et al. 1982). Subsequent work established the no observable effect level (NOEL) for shell thickening in this, the most sensitive of the tested species, at about 20 ng/L. It has been suggested that shell thickening is a consequence of the effect of TBT on mitochondrial oxidative phosphorylation (Alzieu et al. 1982). Reduced ATP production may retard the function of Ca++ ATPase, which is responsible for the Ca++ transport that leads to CaCOj deposition during the course of shell formation. Abnormal calcification causes distortion of the shell layers. [Pg.176]

Although the likelihood for biologically harm has not been assessed fully, for most EDCs the exposure concentrations in ambient environments (away from hotspots of chemical discharges) would suggest that they are insufficient to do so. Exceptions to this inclnde the case studies detailed in the previous section. It should, however, also be emphasized that most studies on the effects of EDCs under controlled laboratory conditions have not considered long-term chronic exposures encompassing full life cycles, and some wildlife species are exposed lifelong to some of the EDCs described earlier. [Pg.283]

Toxoid vaccines. Toxoid vaccines are preparations derived fiom the toxins that are seereted by eertain species of bacteria, hi the manufacture of such vaccines, the toxin is separated fiem the bacteria and treated in a way that eliminates toxicity without eliminating immunogenicity. Formalin (ca. 38% of formaldehyde gas in water) is used for this purpose and consequently the treated toxins are often referred to as formol toxoids. Toxoid vaccines are veiy effective in the prevention of those diseases such as diphtheria and tetanus in which the harmful effects of the infecting bacteria are due to the deleterious action of bacterial toxins on physiology and biochemistry. [Pg.306]

Bokern M, HH Harms (1997) Toxicity and metabolism of 4- -nonylphenol in cell snspension cnltnres of different plant species. Environ Sci Technol 31 1849-1854. [Pg.614]

Environmental pollution caused by pesticides has become a serious problem. Especially during and/or after pesticide application to crops, the pesticides are released into sensitive environmental areas, and also into ground and surface water, and could be harmful or dangerous to humans and other species. Therefore, very low concentrations of diphenyl ether herbicides in environmental waters must be monitored. [Pg.461]


See other pages where Species harmful is mentioned: [Pg.822]    [Pg.29]    [Pg.822]    [Pg.118]    [Pg.109]    [Pg.1062]    [Pg.822]    [Pg.29]    [Pg.822]    [Pg.118]    [Pg.109]    [Pg.1062]    [Pg.37]    [Pg.368]    [Pg.212]    [Pg.232]    [Pg.500]    [Pg.427]    [Pg.354]    [Pg.112]    [Pg.402]    [Pg.253]    [Pg.479]    [Pg.371]    [Pg.215]    [Pg.11]    [Pg.22]    [Pg.199]    [Pg.17]    [Pg.272]    [Pg.321]    [Pg.194]    [Pg.377]    [Pg.234]    [Pg.255]    [Pg.66]    [Pg.125]    [Pg.127]    [Pg.80]    [Pg.118]    [Pg.304]    [Pg.1020]   
See also in sourсe #XX -- [ Pg.46 ]




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