Our Contaminated World

Dr. David Crews presents lessons from biology in HI’s Faculty Fellows Seminar on Health, Well-Being, Healing
By Saralyn McKinnon-Crowley

At this week’s Faculty Fellows Seminar, Dr. David Crews (Integrative Biology) spoke about the mutual interdependence of the environment and human biology. Dr. Crews argued that the environment is permanently contaminated by the mass production of synthetic chemicals and other factors, and it is now impossible to return it to pre-Industrial Revolution conditions. Biological effects from human exposure to these chemicals can occur generations after the initial encounter (a process known as synchronicity). The impact of these chemicals can be seen beyond gene expression and, indeed, extends to human psychological and emotional responses. To illustrate these changes, Dr. Crews used the example of endocrine disrupters (EDCs)—chemicals that disrupt the collection of glands that secrete hormones into the circulatory system to be carried to target organs.

Structural formula for polychlorinated biphenyls
Structural formula for polychlorinated biphenyls

Dr. Crews specifically discussed one type of EDC, polychlorinated biphenyls (PCBs), man-made chemicals used widely in industrial and commercial products . Even though the industrialized world ceased use of PCBs in the 1970s, PCB levels are still present in organisms today and have even been found in the Arctic Circle.

Dr. Crews argued that the environment has a substantial impact on human biology, which in turn has an impact on human behavior. The theoretical approach known as epigenetics attempts to bridge the gap between the study of biological processes at the micro level and large-scale phenomena (at the macro level). In epigenetics, the unit of analysis is not the individual gene, but rather an entire organism and how its genetic expressions influence and are influenced by the organism’s environment. From a study done on rats, we know that environmental modifications such as exposure to an EDC can impact the contemporary population as well as later generations, and biological effects can even skip a generation.

This means that human beings are still experiencing the burdens of chemicals that have been absent from production and out of use for decades.  Dr. Crews added that though chemical contamination is permanent, efforts to cleanse the environment (such as the Hudson River PCB Dredging Project)—in which 310,000 pounds of PCBs were removed from the Upper Hudson River—are indeed worthwhile.  For instance, Richard Goldschmidt’s “hopeful monster,” an entirely new biological entity created through adaptive genetic change, illustrates the constructive element of human adaptation to contamination.  Cultural adaptation can lead to biological adaptation. Our environmental contamination does not mean a death sentence for the human race.

Dr. Crews’ proposed policy solution to these biological facts is a work-in-progress. This week’s seminar discussion resembled the semester’s first Faculty Fellows meeting, in which Dr. Barrish discussed how speculative fiction generally and On Such a Full Sea specifically both include attempts to model an unpredictable future in the face of a contaminated world. Both On Such a Full Sea and this week’s presentation encourage us to ponder the consequences of our current societal trajectory.

Faculty Fellows may access the PowerPoint that Dr. Crews used during his seminar presentation on HI’s Faculty Fellows Canvas page under “Modules” and “Files.”

Leave a Reply

Your email address will not be published.