Glaser's "Chemistry is in the News"
To A ccompany Wade Organic Chemistry 4/e.
Chapter 19. Amines
Chapter 20. Carboxylic Acids.
Nature vers us Nurture, Darwin versus Creationists, the Church versus Galileo…all debates which threatened science and divided groups of people. Today a new debate wages on: pesticides and growth regulators versus a health conscious society. As consumers and future parents what are we to make of such a controversial debate?
In 1989 the CBS news program "60 Minutes" ran two controversial segments confronting the dangers of pesticides and growth regulators, which are used during the maturation of fruits and v egetables. The growth regulator Daminozide (Alar) was at the center of this debate.
The greatest danger presented by Alar is the by product unsymmetrical dimethyl hydrazine (UDMH). Use Chemfinder to determine the structure of Al ar and its byproduct UDMH. UDMH is formed when apples treated with daminozide are processed during the production of applesa uce and various juices. After extensive testing scientists have determined the UDMH is a carcinogen, a development, which places children at great risk since they frequently consume excessive amounts of apple products.
Although many reputable sources are confident that Alar is a potentially dangerous carcinogen, not a ll experts are convinced. Reports done by the Extension Toxicology Network (Extoxnet) suggest that although Alar and its by product UDMH are dangerous when ingested in exceptionally large quantities, they are practically nontoxic to mammals during normal consumption. Extensive testing done on lab animals such as r ats and swine has lead to mixed results, however the effects on humans have yet to be determined.
Experts on both sides of the debate agree that certain precautions can be taken to ensure unnecessary consumption of dangerous products does not occ ur. Consumers should wash all fruits and vegetables thoroughly before eating, avoid eating the skin of fruits and vegetables and beware of perfect looking produce. Today there is new movement toward the production of organically grown foods. Critics protest that the production of organic foods is not cost efficient because the use of pesticides increases the yield of many products and are quick to point out the increased risk of the presence of E. C oli bacteria in organically produced foods.
After 60 Minutes aired the segment "A is for Apple" hysteria focused on the contamination of fruits and vegetables through the use of pesticides and growth regulators started. The Alar incidents were a fruit of such hysteria. Following the 1989 news segment the EPA encouraged the Uniroyal Chemical Corporation to end the production of their growth re gulator Alar. The Uniroyal Chemical Corporation ended production voluntarily but the debate whether this decision was merited still rages.
What is the IUPAC name for Alar (Daminozide)?
N-dimethylamino-beta-carbamyl propionic acid
When Alar reacts with water the metabolite UDMH is formed. Propose a mechanism for this reaction.
Ple ase keep in mind that this reaction is not kinetically favored. Therefore the "driving force" for the reaction is greatly due to metals and microorganism present in "tap" water.
Propose a synthesis for the formation of Daminozide starting with 1,2 dibromo ethane. What problems may result from this synthesis? What can be done to remedy the problem?
When diamonozide is synthesized small am ounts of UDMH are formed from reactions with “tap water". If diamonozide was mixed in deionized water it would not degrade to UDMH. That could possibly solve the problem with UDMH being present in synthesis. Instead of using "tap water" as a solvent wi th the permanganate deionized water could be used.
Did the hysteria following the 60 Minutes segment "A is for Apple" justify pulling Alar off th
e market although the health consequences of the product are still unknown?
Yes, because a reasonable amount of uncertainty remains regarding the health consequences of Alar, however further testing should be done to determine the dangers prese nted when this product is ingested or inhaled.
Although the health effects of Alar on humans have not been determined, studies have been done on the effect of Alar on the environment. According to The Extoxnet cite
what effects does Alar have on the soil and groundwater?
Alar has low soil persistence in fact the half-life of Alar is 21 days. 50% of applied Alar disappears within 1 week. Alar is soluble in water and therefore does not persist in soil, wh ich inhibits its ability to contaminate groundwater.
Question 6: Weight loss drugs, experimental surgeries, cellular phones and pesticides are all products available today to make life better or reduce the costs of manufacturing or living. What many consumers do not know or choose to ignore are the potential harmful side effects produced when these products are used. The potentially harmful nature of such products ignites the debate whether their use is ethically sound. If yo u were running a business would you sell such products? What if you were raising a family?