Abstract
Every year in November, the American College of Toxicology (ACT) convenes its annual meeting to conduct its business and stage a scientific program for its members and others who might have an interest. The scientific program, which requires a year of planning, consists of Plenary Lectures, Scientific Symposia, Poster Presentations, and Continuing Education courses, and both the planning and execution of the program are remarkably efficient and effective. The ACT annual meeting provides a valuable resource for the professional toxicologist while at the same time providing a service to medicine, biology, and society at large.
The plenary lectures are noteworthy for 2 reasons. First, the ACT leadership appears to view the plenary lectures as an opportunity for the ACT membership to experience an education or at least exposure to important topics that may not necessarily be directly related to toxicology—the equivalent of providing a liberal arts experience. Second, the speakers for the plenary lectures are invited and they are selected as being recognized leaders in their respective fields, giving the lectures authenticity and superior quality.
The ACT officers and the leadership responsible for planning the annual meeting over the years have selected and invited plenary lecturers with great care and wisdom. Each year, the implied bar of excellence is either met or exceeded for the selected lecturers. From the membership’s perspective, attending the plenary lectures is worth the price of admission and attendance at the annual meeting alone, although such a view does not belittle the other activities associated with the ACT annual meeting.
The slate of plenary lectures for the 2011 annual meeting of ACT met the high-quality standard. In addition, one of the plenary lectures merits special attention because of the importance of the subject matter. There may be slowness to perceive the significance this plenary lecture, which may be due to an initial reaction of its title: “Climate Change and Speaking the Truth to Power: How Sound Science Can Inform Wise Policy.”
The advertized topic of this lecture brings into focus the intersection of a scientific endeavor with firm sociopolitical convictions that are usually reserved for discussions outside toxicology. The debate on global warming surrounding the lecture’s topic, which on the surface may not appear to be related to toxicology, does have much to do with toxicology. For the most part, toxicologists as a group are politically benign and are not inclined to be the instigators that stir the cauldron of political discontent. When toxicologists do get in the midst of some sort of fray, it is usually because they have been thrust there under the aegis of being “the bearer of bad news.” It is not the intent of this commentary to place toxicology into an advocacy role for one side or the other in the global warming discussion. However, under the banner of self-preservation for all, toxicologists must recognize and appreciate an important consequence of the message that the lecture delivered.
Richard C. J. Somerville, PhD, Distinguished Professor Emeritus & Research Professor, Scripps Institution of Oceanography, University of California San Diego, gave the lecture, and Dr Somerville’s presentation was devoid of the typical political rhetoric associated with discussions about climate change. He made a convincing argument for global warming that was based on scientific evidence. But what does an accomplished researcher who studied atmospheric clouds has to do with toxicology? Plenty!
It is beyond the scope and indeed the possibility to settle here in this commentary whether or not global warming is just a normal climatic cycle or an association of anthropogenic activity. This type of debate is akin to the age-old debates toxicologists have faced with epidemiologists centered on association versus causation of adverse human health effects. Does it really matter to a toxicologist whether human activity has caused global warming or whether global warming is a natural phenomenon? Not really, and that is not the issue for toxicologists. Rather, Dr Somerville pointed out, which can be supported by empirical observations, there is a body of evidence indicating that global warming is real 1 and sea levels around the world are rising. 2 His argument is logical, reasonable and consistent, and independent of any political persuasion. Furthermore, and as a matter of common sense, it probably is not a good thing that polar ice is disappearing.
From 1979 to 1983, Arctic ice covered 7.5 million km2, while at the end of the summer of 2011, the coverage was 4.6 million km2 indicating that the amount of polar ice is shrinking. 3 These data along with the atmospheric temperature and sea level data represented by their hockey stick-like curves look strikingly similar to another hockey stick curve: atmospheric CO2 concentrations. 4 Association, correlation, or causal—you be the judge. The important issue for toxicologists is the loss of polar ice and the subsequent toxicological consequences of the melting process which are separate from pro-global warming and the antiglobal warming groups’ wars of words.
Putting aside the political debates, there are facts that are precursors to inevitable observations and events. Given the facts that global temperatures are rising and polar ice is disappearing, it can reasonably be concluded that the sea level is rising because polar ice is melting. However, for the toxicologists, rising sea levels are less important than something else that is happening.
Not so long ago, but long enough that many practicing toxicologists today were either not yet born or too young to see the initial revelation and subsequent evolution of the concept of persistent organic chemicals (POCs). If you missed the flurry of health effects’ investigations that were conducted for POCs during the first run, fear not. Like a boomerang, POCs are returning, certainly not by popular demand, for a second run.
With the melting of polar ice, there is the reappearance in the environment of POCs that were trapped within the polar ice matrix. 5,6 Once the incarcerated molecules are released from their prisons of ice, they scurry to form vapors and develop into aerosols by combining with other atmospheric schmutz to form clouds. 7 A vivid imagination is not required to appreciate that there will likely be exposure to humans by various routes of the once trapped POCs which are part of aerosols and clouds waft across the planet.
While most toxicologists are not capable of clarifying the magnitude of exposure these POCs might present, they are qualified and capable of assessing the historically established health effects for POCs and their no-effect levels. Toxicologists will be called upon today to opine on the human health effects and to contribute to human health risk assessments for these old POCs, many of which are no longer found in commerce. Are the no-effect levels that were determined during the POCs first run the same today? The simple and neat solution is to dig out the old toxicology studies that were conducted on the POCs, using them without further analyses and quietly ignoring the progress that has been made in the last 50 years in toxicological methods and procedures. But then with a straight face, those who would use the old studies without a critical analysis would have to ignore the wisdom of Henry Louis Mencken (1880-1956), “For every complex problem there is a solution that is simple, neat, and wrong.” 8
