Tuesday, April 7, 2009
Transgenic sweet corn containing the genes for expression of Bacillus thuringiensis toxins has been developed and is actually in the marketplace in the European Union and North America. B. thuringiensis (Bt) is a naturally-occurring bacterium that was found to produce exotoxins with insecticidal properties. The HD-1 strain of Bt was the first microbe to be successfully commercialized and used in caterpillar control, and it continues to be used as a microbial insecticide. In fact, several other strains of the bacterium have been developed for control of beetles, flies and mosquitoes. The genes for expression of these toxins have been identified, isolated and inserted into the genomes of crop plants. As susceptible insects feed upon the plant, they also consume the insecticidal toxin(s). Transgenic cotton and maize with the Bt toxin trait are now commonly grown in North America. Sweet corn is commonplace in our supermarkets, local markets, and on our tables. Will Bt sweet corn be the variety of choice for producers who supply our markets and our tables with the summer delicacy? What are the risks and the benefits for producers and consumers?
Sunday, March 29, 2009
The New York Times, CNN Headline News, Atlanta Journal-Constitution, ABC Evening News... the news has been filled with reports of Salmonella in peanut butter and other peanut products, and right here in Georgia! But, many other problems occur in our foods. Microbes, antibiotics, hormones, genetically-modified organisms (GMOs), pesticides, and much more... But, what's impacting human health and what's not? And, who's responsible for the oversight? There's lots to cover and discuss here. Wade in to direct where we'll go with this last topic for the semester.
Monday, February 16, 2009
Wooden utility poles, railroad ties, fence posts, and other materials are protected from rapid degradation by wood preservatives. In a recent reassessment report, the EPA acknowledged that these chemicals and their byproducts (dioxins, furans, creosote, hexachlorobenzene, etc.) pose environmental and human health risks. Some environmental groups are pressuring the EPA and our current administration to ban the use of these materials. Other countries have switched to alternatives that are not composed of wood (concrete, steel, recycled composites). Should the U.S. do the same? What are the risks involved in continued usage of these chemical preservatives? What are the economics involved in switching to alternatives? Do the risks merit a ban of these chemical preservatives?
Monday, January 12, 2009
Malaria kills more than 1 million people each year. Most are children in Africa and Southeast Asia. African nations have set a goal of halving mortality caused by malaria on that continent by the year 2010, and the government of the Peoples Republic of China has taken steps to assist with managing malaria across its borders with Southeast Asian countries. These collective efforts face some significant health, environmental and political impediments. One of the focal issues is the use of the insecticide DDT as an indoor residual spray to control mosquitoes that vector the malarial disease-causing protozoan. Some suggest an increased use of the indoor DDT sprays, even in light of this chemical being banned by many governments because of its reportedly negative environmental and health impacts. This debate threatens to derail the progress of discussions and efforts to abate and prevent malaria.