Toxic Environmental Compounds

Shitanda I, Takamatsu S, Watanabe K, Itagaki M (2009) Amperometric screen-printed algal biosensor with flow injection analysis system for detection of environmental toxic compounds. Electrochim Acta 54 4933... 

The compound is relatively nontoxic. Because many golf courses and recreational grassy areas abut lakes and ponds that are used for fishing, the environmental toxicity data are important. The LC q for trout (96 h) is 80 mg/L for bluegiU. (96 h), 36 mg/L and for Daphnia, 64 mg/L. 

In order to circumvent this problem, there has been significant activity directed toward the search for a less environmentally toxic and more selective oxidizing agent than chromium. For example, Hoechst has patented a process which uses organorhenium compounds. At a 75% conversion, a mixture of 86% of 2-methyl-l,4-naphthoquinone and 14% 6-methyl-l,4-naphthoquinone was obtained (60). Ceric sulfate (61) and electrochemistry (62,63) have also been used. 

Previously, we have shown that functional secretion of OPH molecules into the periplasmic space induced about 2.8-fold higher specific whole cell OPH activity [10]. From the detail reaction kinetic studies in this work, we showed that this periplasmic space-secretion strategy provided much improved bioconversion capability and efficiency ( 1.8-fold) for Paraoxon as a model organophosphate compound. From these results, we confirmed that Tat-driven periplasmic secretion of OPH can be successfully employed to develop a whole cell biocatalysis system with notable enhanced bioconversion efficiency and capability for environmental toxic organophosphates. 

To express that it is not just the amount of waste but rather its environmental impact, Sheldon introduced the environmental quotient EQ as the E factor multiplied by an unfriendliness quotient, Q, which can be assigned a value to indicate how undesirable a byproduct is. For example, Q = 0 for clean water, 1 for a benign salt, NaCl, and 100-1000 for toxic compounds. Evidently, catalytic routes that avoid waste formation are highly desirable, and the more economic value that is placed on, for example, the unfriendliness quotient, the higher the motivation to work on catalytic alternatives. Waste prevention is much to be preferred over waste remediation. 

Costa M, Christie NT, Cantoni O, ZelikofF JT, Wang XW, Rossman T. 1991. DNA damage by mercury compounds an overview. In Suzuki T, Imura N, Clarkson TW, editors. Advances in mercury toxicology — Rochester Series on Environmental Toxicity. New York (NY) Plenum Press, p. 255-273. 

This property of organophosphate esters may be of environmental importance since phosphoric acid diesters are much more soluble and very little is known concerning the environmental toxicity of these compounds. The available data do not provide sufficient descriptions of the experimental methods to determine if the rates are reliable (Barnard et al. 1961 Ciba-Geigy 1984e, 1986 Howard and Deo 1979 Mayer et al. 1981 Wolfe 1980). The majority of reports provide only a minimum of information and exclude important facts such as the duration of the experiments and the concentration of buffers. Despite the lack of experimental detail, published rate constants for base-catalyzed hydrolysis appear to be reasonably consistent and suggest that the hydrolytic half-life of triphenyl phosphate will vary from... 

Jacinto, M.J., Santos, O., Landers, R., Kiyohara, P.K. and Rossi, L.M. (2009) On the catalytic hydrogenation of polycyclic aromatic hydrocarbons into less toxic compounds by a facile recoverable catalyst. Applied Catalysis B Environmental, 90 (3-4), 688-692. 

The increase in environmental awareness and the acute effects of some toxic compounds have raised questions over the safety of using many chemicals invented for agricultural and industrial applications. A great deal of current research addresses the management and remediation of old contaminated sites. Recent concerns regard the safety of consumer chemicals, especially nanomaterials the effect of pharmaceuticals on ecosystems and the combined effect that chemical cocktails have on human and ecosystem health. 

Edney E, Mitchell S, Bufalini JJ. 1982. Atmospheric chemistry of several toxic compounds. Research Triangle Park, NC U.S. Environmental Protection Agency, Office of Research and Development. 

Consequently, Europe has historically been a hotspot of environmental pressures because of the contamination caused by agricultural, municipal, and industrial activities and high population densities [5, 6], Such contamination has led to poor water quality in many European river basins [7-12], In addition, this pollution can cause the accumulation in river sediments of toxic compounds such as pesticides [13], surfactants [14], and alkyl polycyclic aromatic hydrocarbons (PAHs) [15], These can in turn act as a source to biota [16] and as a potential risk for entire ecosystems [17] if the compounds bioaccumulate, and thereby enter the food chain [18],... 

Electrolysis is an environmentally friendly technology. Properly designed electrochemical processes which use a mass-free reagent (the electron without the need of additional chemicals at ambient temperature) do not produce unwanted effluents, they often do not need toxic compounds (such as CN ) and do not introduce hazards of their own. 

Similarly, legislation has been, or will be, introduced to deal with the disposal of treated wood waste at the end of a product lifetime. No longer will it be acceptable to dispose of treated wood waste by dumping in landfill. Proper disposal will require the incineration of treated wood waste in appropriate facilities that have the necessary equipment to prevent stack emissions of toxic compounds. This requires expensive investment to build plant that can meet the relevant environmental requirements. Such methods probably represent the best option for the permanent removal of these potential pollutants. The ash generated in these plants may contain high concentrations of arsenic, which will then have to be disposed of as hazardous waste. 

Compound Class or Principal Use Human Toxic Effects Environmental Toxic Effects... 

Burks, S.L. Evaluation of the effectiveness of granular activated carbon adsorption and aquaculture for removing toxic compounds from treated petroleum refinery effluents, Robert S. Kerr Environmental Research Laboratory. U.S. EPA Report 600/2-81-067, 1981. 

Hawkshead JJ (2008) Hospital wastewater containing pharmaceuticals active compounds and drag-resistant organisms a source of environmental toxicity and increased antibiotic resistance. J Residual Sci Tech 5 51-60... 

Contaminants may be adsorbed on the solid phase or on suspended particles in the liquid phase. Environmental factors, such as temperature, pH, and water content in the subsurface prior to contamination, also affect the nature of contaminant adsorption. Other physical processes of retention include precipitation, deposition, and trapping. Under natural conditions, pollutants often consist of more than a single contaminant, comprising a mixture of organic and inorganic toxic compounds. Each of these compounds can react differently with the existing minerals and chemicals in the subsurface. 

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