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Industrial Chemicals (industrial + chemical)
Selected AbstractsEfficient Tetrahydropyranylation of Alcohols and Detetrahydropyranylation Reactions in the Presence of Catalytic Amount of Trichloroisocyanuric Acid (TCCA) as a Safe, Cheap Industrial Chemical.CHEMINFORM, Issue 7 2005Habib Firouzabadi No abstract is available for this article. [source] Too small for concern?AUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 4 2007Public health, nanotechnology Abstract While advances in nanotechnology promise to deliver significant benefits to many aspects of health care, there is increasing concern that regulatory regimes do not adequately capture the potential risks associated with this new technology. Concerns have arisen due to preliminary evidence suggesting that some engineered nanoparticles may display undesirable toxicological properties, presenting potential risks to human and environmental health and safety. Within this context, the role of Australia's National Industrial Chemicals and Assessment Scheme and the Therapeutic Goods Administration in regulating nano-based substances is explored. Drawing on earlier regulatory failures, combined with the scientific uncertainty surrounding nanotechnology, this article recommends that Australia adopt a proactive regulatory approach to nanotechnology through amendments to present legislative regimes. The approach articulated in this article strikes a balance between the current approach and that of the European Union's comprehensive new chemicals regime. Immediate regulatory change is called for in order to ensure that the health of the Australian public is adequately protected over the coming years. [source] Direct and indirect effects of a potential aquatic contaminant on grazer,algae interactionsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2009Michelle A. Evans-White Abstract Contaminants have direct, harmful effects across multiple ecological scales, including the individual, the community, and the ecosystem levels. Less, however, is known about how indirect effects of contaminants on consumer physiology or behavior might alter community interactions or ecosystem processes. We examined whether a potential aquatic contaminant, an ionic liquid, can indirectly alter benthic algal biomass and primary production through direct effects on herbivorous snails. Ionic liquids are nonvolatile organic salts being considered as an environmentally friendly potential replacement for volatile organic compounds in industry. In two greenhouse experiments, we factorially crossed four concentrations of 1-N-butyl-3-methylimidazolium bromide (bmimBr; experiment 1: 0 or 10 mg/L; experiment 2: 0, 1, or 100 mg/L) with the presence or absence of the snail Physa acuta in aquatic mesocosms. Experimental results were weighted by their respective control (no bmimBr or P. acuta) and combined for statistical analysis. When both bmimBr and snails were present, chlorophyll a abundance and algal biovolume were higher than would be expected if both factors acted additively. In addition, snail growth rates, relative to those of controls, declined by 41 to 101% at 10 and 100 mg/L of bmimBr. Taken together, these two results suggest that snails were less efficient grazers in the presence of bmimBr, resulting in release of algae from the grazer control. Snails stimulated periphyton primary production in the absence, but not in the presence, of bmimBr, suggesting that bmimBr also can indirectly alter ecosystem function. These findings suggest that sublethal contaminant levels can negatively impact communities and ecosystem processes via complex interactions, and they provide baseline information regarding the potential effects of an emergent industrial chemical on aquatic systems. [source] Relevance of the developmental toxicity of ethanol in the occupational setting: a review,JOURNAL OF APPLIED TOXICOLOGY, Issue 5 2003Lorraine F. H. Irvine Abstract Numerous studies have been conducted investigating the reproductive toxicology of ethanol, the overwhelming majority concerning the adverse effects of consuming alcohol in beverages during pregnancy. Because many of the in vivo studies were designed to model alcoholism, they used comparatively high doses and assessed relatively few endpoints. Outcomes may have been affected by disturbances of metabolism at such high exposures, giving rise to secondary effects on development. The available data on ethanol from ,conventional' developmental toxicity study test methods of the type used for regulatory hazard assessment of chemicals are limited. It is in this context, however, i.e. the use of ethanol as an industrial chemical rather than as a component of beverages, that this review is based. Using the usual criteria applied for the purpose of hazard assessment of industrial chemicals, it is concluded that there is no evidence that industrial exposure to ethanol is a developmental toxicity hazard. Developmental toxicity may result from drinking alcoholic beverages, the threshold level for all aspects of which has yet to be de,ned. This is not, however, considered relevant to the low blood alcohol concentrations resulting from any conceivable inhalation or dermal exposure in the workplace or through the directed use of any consumer product containing ethanol. Copyright © 2003 John Wiley & Sons, Ltd. [source] Percutaneous toxicokinetic and repeated cutaneous contact studies with ethylene glycol monohexyl etherJOURNAL OF APPLIED TOXICOLOGY, Issue 5 2003Bryan Ballantyne Abstract Ethylene glycol monohexyl ether (EGHE; CAS no. 112-54-4) is a liquid industrial chemical with a potential for skin contact. The toxicokinetics of EGHE was investigated in Fischer 344 rats and New Zealand White rabbits by intravenous (i.v.) and 48-h occluded epicutaneous dosing. Given i.v. to male rats (2.5,25 mg kg,1) [14C]EGHE demonstrated ,rst-order kinetics. Carbon-14 was eliminated mainly in urine (68,74%) as metabolites, with no free EGHE. The plasma free EGHE concentration declined rapidly post-dosing and was not detectable by 8 h. Similar results were obtained for [14C]EGHE given i.v. to male rabbits in the dosage range 1,10 mg kg,1, except that the metabolism of EGHE was more rapid, with no free EGHE being detectable in plasma by 1 h post-dosing. After cutaneous dosing of male and female rats with 25 mg kg,1, there was rapid percutaneous absorption, with >95% of the radiochemical dose being recovered. Percutaneous bioavailability was >75%. Carbon-14 was excreted in urine (21,33%) to a lesser extent than by the i.v. route, and 14CO2 and volatiles accounted for 15,18%. Carbon-14 recovery was low from tissues and organs (0.39,0.46%), with no preferential accumulation. Extensive metabolism was indicated by the rapid decline in plasma free EGHE, with none being detectable by 48 h. Free EGHE was not present in urine, and urinary radioactivity was associated with up to seven metabolites. After cutaneous dosing of male and female rabbits (10 mg kg,1) ca. 75% of the dose was recovered, most 14C being in urine (58,60%). Urine radioactivity was associated with up to nine metabolite peaks, but no free EGHE. The toxicokinetic ,ndings indicate a signi,cant percutaneous absorption of EGHE across both rat and rabbit skin, which is rapidly and extensively metabolized, with renal excretion being the principal route of elimination of metabolites. A 9-day repeated skin contact study in the male and female New Zealand White rabbit, using a dosage range of 44,444 mg kg,1 day,1, did not show any evidence for percutaneous systemic toxicity. Copyright © 2003 John Wiley & Sons, Ltd. [source] Sustainable futures: Encouraging risk screening of industrial chemicals at the R&D stageENVIRONMENTAL QUALITY MANAGEMENT, Issue 4 2004Maggie Wilson First page of article [source] Alternative approaches can greatly reduce the number of fish used for acute toxicity testingENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 5 2006Conny C. Hoekzema Abstract Acute toxicity tests with algae, daphnids, and fish are required for the classification and environmental risk assessment of chemicals. The degree of risk is determined by the lowest of these acute toxicity values. Many ecotoxicological programs are seeking to reduce the numbers of fish used in acute toxicity testing. The acute threshold test is a recently proposed strategy that uses, on average, only 10 (instead of 54) fish per chemical. We examined the consequences of reducing the number of fish used in toxicity testing on the ultimate outcome of risk assessments. We evaluated toxicity data sets for 507 compounds, including agrochemicals, industrial chemicals, and pharmaceuticals from our internal database. Theoretical applications of the acute threshold test gave similar results to those obtained with the standard fish median lethal concentration (LC50) test but required only 12% as many fish (3,195 instead of 27,324 fish used for all compounds in the database). In 188 (90%) of the 208 cases for which a complete data set was available, the median effect concentration for algae or daphnids was lower than the LC50 for fish. These results show that replacement of the standard fish LC50 test by the acute threshold test would greatly reduce the number of fish needed for acute ecotoxicity testing without any loss of reliability. [source] Relevance of the developmental toxicity of ethanol in the occupational setting: a review,JOURNAL OF APPLIED TOXICOLOGY, Issue 5 2003Lorraine F. H. Irvine Abstract Numerous studies have been conducted investigating the reproductive toxicology of ethanol, the overwhelming majority concerning the adverse effects of consuming alcohol in beverages during pregnancy. Because many of the in vivo studies were designed to model alcoholism, they used comparatively high doses and assessed relatively few endpoints. Outcomes may have been affected by disturbances of metabolism at such high exposures, giving rise to secondary effects on development. The available data on ethanol from ,conventional' developmental toxicity study test methods of the type used for regulatory hazard assessment of chemicals are limited. It is in this context, however, i.e. the use of ethanol as an industrial chemical rather than as a component of beverages, that this review is based. Using the usual criteria applied for the purpose of hazard assessment of industrial chemicals, it is concluded that there is no evidence that industrial exposure to ethanol is a developmental toxicity hazard. Developmental toxicity may result from drinking alcoholic beverages, the threshold level for all aspects of which has yet to be de,ned. This is not, however, considered relevant to the low blood alcohol concentrations resulting from any conceivable inhalation or dermal exposure in the workplace or through the directed use of any consumer product containing ethanol. Copyright © 2003 John Wiley & Sons, Ltd. [source] Ecotoxicity testing of chemicals with particular reference to pesticidesPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 7 2006Colin H Walker Abstract Ecotoxicity tests are performed on vertebrates and invertebrates for the environmental risk assessment of pesticides and other chemicals and for a variety of ecotoxicological studies in the laboratory and in the field. Existing practices and strategies in ecotoxicity testing are reviewed, including an account of current requirements of the European Commission for the testing of pesticides and the recent REACH (Registration, Evaluation, Authorisation and Restrictions of Chemicals) proposals for industrial chemicals. Criticisms of existing practices have been made on both scientific and ethical grounds, and these are considered before dealing with the question of possible alternative methods and strategies both for environmental risk assessment and for ecotoxicological studies more generally. New approaches from an ecological point of view are compared with recent developments in laboratory-based methods such as toxicity tests, biomarker assays and bioassays. With regard to the development of new strategies for risk assessment, it is suggested that full consideration should be given to the findings of earlier long-term studies of pollution, which identified mechanisms of action by which environmental chemicals can cause natural populations to decline. Neurotoxicity and endocrine disruption are two cases in point, and biomarker assays for them could have an important role in testing new chemicals suspected of having these properties. In a concluding discussion, possible ways of improving testing protocols are discussed, having regard for current issues in the field of environmental risk assessment as exemplified by the debate over the REACH proposals. The importance of flexibility and the roles of ecologists and ecotoxicologists are stressed in the context of environmental risk assessment. Copyright © 2006 Society of Chemical Industry [source] A STEPWISE CONFIDENCE INTERVAL PROCEDURE BASED ON AN ASYMMETRIC LOSS FUNCTION WITH APPLICATIONS TO TOXICOLOGICAL EVALUATIONAUSTRALIAN & NEW ZEALAND JOURNAL OF STATISTICS, Issue 1 2010Jian Tao Summary The purpose of toxicological studies is a safety assessment of compounds (e.g. pesticides, pharmaceuticals, industrial chemicals and food additives) at various dose levels. Because a mistaken declaration that a really non-equivalent dose is equivalent could have dangerous consequences, it is important to adopt reliable statistical methods that can properly control the family-wise error rate. We propose a new stepwise confidence interval procedure for toxicological evaluation based on an asymmetric loss function. The new procedure is shown to be reliable in the sense that the corresponding family-wise error rate is well controlled at or below the pre-specified nominal level. Our simulation results show that the new procedure is to be preferred over the classical confidence interval procedure and the stepwise procedure based on Welch's approximation in terms of practical equivalence/safety. The implementation and significance of the new procedure are illustrated with two real data sets: one from a reproductive toxicological study on Nitrofurazone in Swiss CD-1 mice, and the other from a toxicological study on Aconiazide. [source] | ||||||||||