Synthetic chemicals case studies

However, conducting a complete LCA is very time consuming. Fortunately, simple mass balancing may already indicate most relevant requirements for action. This was illustrated by one case study concerning a pharmaceutical intermediate (Scheme 5.1). Compared to LCA, the system boundaries of mass balancing are relatively narrow. For instance, the case study focuses on the chemical reaction and does not take into account the production of substrates. In this respect, a look at two reduction reactions of the synthetic routes via B and via C is worthwhile (Scheme 5.1). 

The purpose of this chapter will be to serve as a critical introduction to the nature and origin of the chemical effects of ultrasound. We will focus on organo-transition metal sonochemistry as a case study. There will be no attempt to be comprehensive, since recent, exhaustive reviews on both organometallic sonochemistry Q) and the synthetic applications of ultrasound (2) have been published, and a full monograph on the chemical, physical and biological effects of ultrasound is in press (3). 

In one epidemiological study of 138 workers exposed to vinylidene chloride in the United States, no excess of cancer was found, but follow-up was incomplete, and nearly 40% of the workers had less than 15 years latency since first exposure (lARC, 1986). In a study in the Federal Republic of Germany of 629 workers exposed to vinylidene chloride, seven deaths from cancer (five bronchial carcinomas) were reported this number was not in excess of the expected value. Two cases of bronchial carcinoma were foimd in workers, both of whom were 37 years old, whereas 0.07 were expected for persons aged 35-39 years (Thiess et al., 1979). The limitations of these two studies preclude assessment of the carcinogenicity of the agent to humans. No specific association was found between exposure to vinylidene chloride and an excess of lung cancer observed in a synthetic chemicals plant in the United States. 

The evolution of novel green production routes for semi-synthetic antibiotics (SSAs) that are replacing existing chemical processes serves as a recent and relevant case study of this ongoing integration of disciplines. We will also show some challenges in this specific field. 

For more examples of synthetic approaches that have reduced the use of ammonia, see also the case studies describing catalytic dehydrogenation of diethanolamine, HCN-free synthesis of the amino acids, and HCN-free synthesis of the specialty chemical, sarcosinate, all listed under the section on hydrogen cyanide, and the case study describing synthesis of the drug aprepitant. 

This book explores the global product stewardship of synthetic chemicals with a particular focus on the regulatory and scientific analyses of the life cycle consequences of bringing a chemical to market. That ossified sentence barely hints at the complexity of choices we make every day, choices that can have effects—or not—halfway around the planet. We humans make sense of the world through the stories we tell. And so, with rigorous attention to fact, this book expands on the bone-dry premise of its opening sentence by using case studies to explore two deliberately naive questions about product stewardship, life cycle analysis, and the environment. 

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