Suchergebnisse

Rachel Carson, in Silent Spring, pointed out that modern pesticides caused serious toxic effects. Since 1962, the book has had a considerable impact, but in the same period of time, the production of organic chemicals has increased more than tenfold. Humans and wildlife are exposed
to a wide range of chemicals including pesticides, but also industrial chemicals such as plastic softeners, flame retardants, impregnating agents, surfactants, colorants, dyestuffs and various chemicals in food packaging. Problematic chemicals are regulated in the EU and worldwide. However,
often a ban on a chemical leads to substitution by chemicals with a similar performance, but also similar unwanted properties. The potential of Green Chemistry to reshape the universe of chemical products has not yet been exploited.

"Transdisziplinarität" erlebt zur Zeit einen stürmischen Aufschwung, in keiner wissenschaftspolitischen Debatte darf sie fehlen. In diesem Wort finden die vielfältigsten Hoffnungen auf eine neue und "bessere" Wissenschaft Ausdruck: Transdisziplinäre
Forschung, so bekommt man zu hören und zu lesen, sei integriert, übergreifend, ganzheitlich, handlungsorientiert, nutzungsbezogen, praxisnah und kommunikationsoffen, sie stimuliere Teamarbeit und überschreite die Grenzen der Fächer und Disziplinen. Mit dieser Diskussion
wird ein Begriff wiederbelebt, der aus den sechziger Jahren stammt. Wird der Transdisziplinarität das gleiche Schicksal beschieden sein wie der Interdisziplinarität - Euphorie am Anfang, doch am Ende Emüchterung über die inhaltlichen und die strukturellen Schwierigkeiten,
welche den hochgesteckten Zielen entegenstehen? Was sollte diesmal anders gemacht werden? Welche Ansprüche kann und soll der Begriff überhaupt erfüllen? Welche Neuerungen in Hochschulpolitik, Forschung und Lehre wären erforderlich? Abstract & Keywords → p. 79

A wide range of chemical substances is used in consumer products for various purposes, including plastic softeners, dyestuffs and colorants, flame retardants, impregnation agents, antioxidants and UV absorbers, preservation agents and biocides, and many others. Among these chemicals, there is a certain fraction of substances with hazardous properties such as persistence, bioaccumulation potential and toxicity (PBT properties) or the ability to interfere with the hormonal system (endocrine disrupting chemicals, EDCs). Large-scale screening exercises have shown that there may be several hundreds of chemicals with PBT properties among the several tens of thousands of substances on the market. There are some groups of chemicals that have raised particular concerns such as polybrominated diphenyl ethers (PBDEs) or long-chain poly and perfluorinated alkyl substances (PFASs). These substances have been regulated or are subject to voluntary phase-out programs; specifically, penta- and octabrominated BDEs are scheduled for elimination globally under the Stockholm Convention on Persistent Organic Pollutants; uses of perfluorooctane sulfonic acid (PFOS) are being restricted under the Stockholm Convention, and perfluorooctanoic acid (PFOA) and C 11 –C 14 perfluorocarboxylic acids are regulated in the European Union as PBT substances and vPvB (very persistent, very bioaccumulative) substances, respectively. In addition, all long-chain PFASs (substances with seven or more perfluorinated carbons) are subject of voluntary phase-out programs conducted by major producers of fluoropolymers and fluorotelomer-based products. However, it has become evident that the replacements of these substances include chemically similar substances, i.e. brominated aromatic substances in the case of PBDEs and shorter-chain PFASs in the case of long-chain PFASs. These are two examples of a substitution process that leads to an incremental rather than a fundamental change in the structure of chemicals used in consumer products. Here we discuss the conditions for incremental and fundamental changes in the substitution process of chemicals.