The water flea, Daphnia magna, is the canary of environmental toxicology. Scientists have found the flea to be sensitive to a wide array of toxic conditions. Unlike a mine, a river can contain multiple toxins, and a wide range of reasons why a Daphnia magna may kick the bucket. In an effort to devise a system of monitoring more subtle changes in toxicity, Dr. Chris Vulpe, associate professor of nutritional sciences and toxicology at UC Berkeley's College of Natural Resources, has pushed environmental toxicogenomics to new heights. By looking at which genes are 'expressed' (turned on and off) by the water flea in response to sub-lethal toxins, Dr. Vulpe can get a good idea of what chemicals, metals, or other agents are present in the river, and how they might result in poor health. This combination of genomics (gene expression) and environmental toxicology is a rapidly growing field, and will enable us to better determine which chemicals or toxins may have lasting health effects on us and our environment. Helen Poynton, a UC Berkeley graduate student in nutritional sciences and toxicology and lead author of the study point out the significance of their study.
"Our study is one of the first proof-of-concepts that aquatic toxicogenomics is possible," said Poynton. "The extra information we get from looking at gene expression could help us make more informed decisions about how harmful a toxicant is, and it could give regulators a new direction that we should be pursuing in monitoring water quality. For instance, we could find that it's necessary to regulate toxicant levels at lower levels, so we can act before toxicants get to the level of actually killing a population."
The rise of toxicogenomics may be more useful in product development, then in monitoring.
"For those in industry, chemicals could be screened for potentially ecological consequences while they are still in development," said Poynton. "In pursuing 10 different chemicals for one application, it may be discovered that one is particularly toxic, so it can be ditched right away. At the same time, if screening reveals that there is little or no impact on gene expression from a particular chemical, why not pursue that one for commercial development?"
Dr. Volpe goes on to summarize how the revolution in genomics technology can help environmental toxicology study.
"What you really want to know is whether there is something that will impact an organism's ability to survive well, including its ability to eat, escape predators or fight infection. That is what genomics could do."
Advances in genomics technology enable us to peer deeper into the workings of biology. As these technologies become cheaper and faster we may soon be looking into our daily routine to figure out how our life and our biology interact. ::UC Berkeley News