Dear EarthTalk: Should those of us who care about our health and the planet be concerned about the new trend in genetic engineering called synthetic biology? - Chrissie Wilkins, Bern, NC
Answer: "Synthetic biology" (or "synbio") refers to the design and fabrication of novel biological parts, devices and systems that do not otherwise occur in nature. Many see it as an extreme version of genetic engineering (GE). But unlike GE, whereby genetic information with certain desirable traits is inserted from one organism into another, synbio uses computers and chemicals to create entirely new organisms.
Proponents of synbio, which include familiar players such as Cargill, BP, Chevron and Du Pont, tout its potential benefits. According to the Synthetic Biology Engineering Research Center (SYNBERC), a consortium of leading U.S. researchers in the field, some promising applications of synthetic biology include alternatives to rubber for tires, tumor-seeking microbes for treating cancer, and photosynthetic energy systems. Other potential applications include using synbio to detect and remove environmental contaminants, monitor and respond to disease and develop new drugs and vaccines.
The Union of Concerned Scientists reports that, thanks to global warming, insects previously stopped by cold winters are already moving to higher latitudes, a phenomenon that could expose an extra two billion people, mostly in developing countries, to the dengue virus over the next half century. Credit: U.S. Department of Agriculture
Proponents of synthetic biology tout its potential for bringing about great advances in medicine, energy and cheaper foods. But health advocates worry that the risks to health and the environment may be too great. Pictured: a researcher using “synbio” to engineer new microbes as an alternative to yeast for turning complex sugars into biofuels. Credit: Lawrence Berkeley Nationall Laboratory/Roy Kaltschmidt
While these and other applications may not be widely available for years, synthetic biology is already in use for creating food additives that will start to show up in products on grocery shelves later this year. Switzerland-based Evolva is using synthetic biology techniques to produce alternatives to resveratrol, stevia, saffron and vanilla. The company's "synthetic vanillin" is slated to go into many foods as a cheaper and limitless version of real vanilla flavor. But many health advocates are outraged that such a product will be available to consumers without more research into potential dangers and without any warnings or labeling to let consumers know they are eating organisms designed and brought to life in a lab.
"This is the first major use of a synbio ingredient in food, and dozens of other flavors and food additives are in the pipeline, so synbio vanilla could set a dangerous precedent for synthetic genetically engineered ingredients to sneak into our food supply and be labeled as 'natural,'" reports Friends of the Earth (FoE), a leading environmental group. "Synthetic biology vanillin poses several human health, environmental and economic concerns for consumers, food companies and other stakeholders."
For example, FoE worries that synbio vanilla (and eventually other synthetic biology additives) could exacerbate rainforest destruction while harming sustainable farmers and poor communities around the world. "Synbio vanillacould displace the demand for the natural vanilla market," reports FoE. "Without the natural vanilla market adding economic value to the rainforest in these regions, these last standing rainforests will not be protected from competing agricultural markets such as soy, palm oil and sugar." Critics of synbio also worry that releasing synthetic life into the environment, whether done intentionally or accidentally, could have adverse effects on our ecosystems.
Despite these risks, could the rewards of embracing synthetic biology be great? Could it help us deal with some of the tough issues of climate change, pollution and world hunger? Given that the genie is already out of the bottle, perhaps only time will tell.
Dear EarthTalk: How is it that global warming could cause an increase in health problems and disease epidemics? Do we have any evidence that it is already happening? - Jim Merrill, Provo, UT
Answer: Global warming isn't just bad for the environment. There are several ways that it is expected to take a toll on human health. For starters, the extreme summer heat that is becoming more normal in a warming world can directly impact the health of billions of people.
"Extreme high air temperatures contribute directly to deaths from cardiovascular and respiratory disease, particularly among elderly people," reports the World Health Organization (WHO). "In the heat wave of summer 2003 in Europe, for example, more than 70,000 excess deaths were recorded."
WHO adds that high temperatures also play a role in elevated levels of ozone and other air pollutants known to exacerbate respiratory and cardiovascular problems. And according to the non-profit Union of Concerned Scientists (UCS), warmer temperatures and higher levels of atmospheric carbon dioxide can stimulate plants to grow faster, mature earlier and produce more potent allergens. "Common allergens such as ragweed seem to respond particularly well to higher concentrations of carbon dioxide, as do pesky plants such as poison ivy. Allergy-related diseases rank among the most common and chronic illnesses" reports the group.
Another way global warming is bad for our health is that it increases extreme weather events that can injure or kills large numbers of people. According to WHO, the number of weather-related natural disasters has more than tripled since the 1960s. Likewise, increasingly variable rainfall patterns combined with higher overall temperatures are leading to extended droughts around the world. "By the 2090s, climate change is likely to widen the area affected by drought, double the frequency of extreme droughts and increase their average duration six-fold," reports WHO. One result is likely to be a downturn in agricultural productivity along with a spike in malnutrition. Another is less access to safe drinking water, a trigger for poor sanitation and the spread of diarrheal diseases-not to mention resource wars.
Perhaps most worrying to public health experts, though, is the potential for global warming to cause a spike in so-called "vector-borne diseases" like schistosomiasis, West Nile virus, malaria and dengue fever. "Insects previously stopped by cold winters are already moving to higher latitudes (toward the poles)," reports UCS. Researchers predict that thanks to global warming an extra two billion people, mostly in developing countries, will be exposed to the dengue virus over the next half century.
A related fear is that thawing permafrost in Polar Regions could allow otherwise dormant age-old viruses to re-emerge. Earlier this year, French and Russian researchers discovered a 30,000 year old giant virus, previously unknown to science, in frozen soil in Russia's most northerly region. While the virus, which researchers dubbed Pithovirus sibericum, is harmless to humans and animals, its discovery has served as a wake-up call to epidemiologists about the potential re-emergence of other viruses that could make many people sick. While some of these re-emergent viruses might also be new to science, others could be revitalized versions of ones we thought we had eradicated, such as smallpox.