In Carson’s Footsteps

Rachel Carson’s urgent call in Silent Spring to research and recognize the effects of chemicals on living beings and their environments is heeded today by a new generation of scientists dubbed “Rachel’s grandchildren.” One such metaphorical granddaughter – Dr. Laura Vandenberg – talked about her own career and laboratory findings during Assembly on May 1; her visit was made possible thanks to the generosity of a past parent, who established the Middlesex Speaker Series in Math and Science in 2015.

An assistant professor and graduate program director in the Department of Environmental Health Sciences at the UMass Amherst School of Public Health and Health Sciences, Dr. Vandenberg explores how early life exposures to chemicals and chemical mixtures can predispose individuals to diseases that manifest later in life. While Ms. Carson’s work focused on the pesticide DDT, Dr. Vandenberg is specifically interested in the class of chemicals termed “endocrine disruptors” and has worked extensively with chemicals used as plasticizers and flame retardants, which people come into contact with more often than they may realize.

While her opposition in 1962 claimed that Rachel Carson preferred “dead children to dead mosquitoes,” Dr. Vandenberg clarified that Ms. Carson never asked for a ban of DDT but instead wrote, “If we are going to live so intimately with these chemicals – eating and drinking them, taking them into the very marrow of our bones – we had better know something about their nature and their power.” In fact, Dr. Vandenberg confirmed, scientists have since determined that all babies are now born “pre-polluted” with hundreds of chemicals in their bodies. “We make choices every day – about the food we eat, the soap and lotion we use, the cleaning products we have in our homes,” she said, “and we don’t think about the effects.”

Briefly summarizing the work of researchers in the 1980s and 1990s, Dr. Vandenberg stated that a large number of manmade chemicals have been found to have the potential to disrupt the endocrine system of animals and humans, which, in turn, can cause abnormalities in development, growth, and reproduction. Her research advisor at Tufts Medical School, Dr. Ana Soto, found that BPA (a chemical used in making plastic containers and bottles) affects the growth of mammary glands – a change that can certainly alter the chances of offspring survival. That BPA has been banned in manufacturing some products, like baby bottles, has only led to another key question: What is BPA being replaced with?

The answer, Dr. Vandenberg said, is that 29 different chemicals are used in plastics instead of BPA. In her own lab during the last five years, she has been studying one of them, BPS, to observe its effects on the function of mammary glands in mice. Thus far, she has learned that mice exposed to low levels of BPS early in life stop producing milk earlier in motherhood – and their babies seek milk less often – which leads to starvation. Those who survive often exhibit abnormal obsessive compulsive behaviors.

In short, “What was old is new, and what was new is old,” Dr. Vandenberg sighed. “We were not asking to substitute BPA with BPS.” Noting that science is “not just for scientists,” she added, “If we do not speak up, and instead live priest-like in our labs, spending public grant money, we are not doing our jobs.” Despite potential backlash from chemical industries and other opponents, she asserted, “This should not keep us from speaking.”

Deeply grateful for the mentorship of people who either included her in their projects or recommended her for great opportunities, Dr. Vandenberg also thanked all the students who work in her lab. “We can do so much more together,” she reflected. “I hope you will find a community after Middlesex that also makes you better than you are.”