Living Downstream: A Scientist's Personal Investigation of Cancer and the Environment

Steingraber examines Rachel Carson’s 1962 book Silent Spring and the impact of her study on both the emerging environmental movement and Steingraber’s personal battle with cancer. Carson—a scientist, writer, and environmental advocate—was concerned that information revealing the connection between chemicals and human health was kept internally within the government and not made public. Carson had access to documents pertaining to debates over chemical safety, but the government often ignored these arguments, and further research was underfunded. Carson’s cause was heightened when she received a letter from a gardener, Olga Owens Hucking, who shared pictures of songbirds lying dead in her backyard, allegedly poisoned by DDT sprayed over her property.

Carson pointed to the spraying of poisonous pesticides in the 1950s to eradicate Japanese beetles from Iroquois County, Illinois, to illustrate how chemicals negatively impact the ecosystem. Although the pesticides didn’t stop the beetle, they weakened other insects, killed birds that ate them, and poisoned animals that ate the birds. The beetles continued spreading west, and the pesticide residues remained in Iroquois County soil and water. Carson noted how scientists researched and published but wouldn’t speak out against pesticide use because of the threat of the government defunding research. Up until her death in 1964, Carson planned to address the scientists who created relationships with organizations that promoted and supported the chemical companies.

Steingraber documents a visit to the Illinois salt marsh with her friend Jeannie, who also had cancer. She juxtaposes descriptions of the areas beauty and the impending dark days ahead for her friend. Steingraber also highlights the relationship between Carson and her friend Dorothy and how they refrained from revealing much about their cancer diagnosis and treatments. Steingraber refers to Carson as an “ordinary woman” who had cancer but asked that her illness remain secret so that her research wouldn’t be viewed as biased.

While Carson’s revelation about individual occurrences of cancer and environmental contamination aren’t enough to establish firm links, the many incidences considered together provide a compelling set of evidence. We have no protection against the carcinogens produced by 20th-century industries. Since World War II, everyone—not just industry workers—has been exposed to the chemicals. Cancer increasingly affects the general population, occurrences of cancer has increased in lab animals exposed to small traces of chemicals, and new information reveals the impact of chemicals on a cellular level. Because conducting research on humans is unethical, data will always be incomplete. Which animals are most suited for testing—and whether their cells and genes react the way as a human’s would to a contaminant—isn’t always known, and the introduction of chemical carcinogens into the environment is often uncontrolled.

Carson’s book has inspired activism and advocacy for the environment. The Committee Against Mass Poisoning—led by Olga Owens Hucking, the same gardener who sent Carson the letter about birds—protested ariel spraying and contaminants as unconstitutional, a violation of human rights and rights to privacy. The group’s letters garnered media attention, allowing Steingraber the attention needed to craft her book.

Changes in cancer incidences reveal valuable evidence and information about causes of cancer. Hereditary cancers take time to change. Environmental factors can be studied based on exposure and location. Information about the type of cancer, stage, patient’s name, location, age, sex, and ethnicity is sent to a cancer registry. Cancer registries standardize data to combat the population’s increasing age and size.

When Steingraber examines graphs and data, she thinks about the stories of the women who represent each dot on the graphs. In addition, she compares data on the changing incidence of cancer against data on ecological change. She reflects on compiling a species inventory to study the composition of a Minnesota forest. Graphs revealed clear trends that she couldn’t see while on the trail in the woods. Discovering and counting the existence of rare plants resulted from her pleasure in recording such species.

Scientific data is skewed by the methodology that scientists use to record it. A significant change in results over several years may not indicate a drastic decrease or increase in a species; rather, it may reveal differences in data collection from one researcher to another. Likewise, more people may be outspoken about cancer today, resulting in increased numbers. Other factors that may skew data include misdiagnosis, changes in categorization of tumors, and medical technology such as mammograms that may have led to increased detection of breast cancer incidence between 1973 and 1991. However, research suggests that the populations most reported as having increased rates in breast cancer were unlikely to have received mammograms.

Breast cancer has decreased since the early 2000s, but there are many conflicting explanations for this. In 2002, decreases were reported in the number of postmenopausal women taking cancer-causing hormone-replacement drugs, the rates of mammography screening, and exposure to other causative agents. Many Illinois cancer registries are new, and populations change as people seek treatment in cities outside the state. Steingraber suggests screening contaminants that act as estrogen—removing estrogen actors and observing the effect on breast cancer rates.

While documenting cancer mortality rates is useful, the data reveals a failure to reduce cancer deaths despite increased funding for cancer treatment and research. However, research suggests that cancer patients are living longer, thus incurring additional economic, social, and psychological costs (45). This is especially true in children. Cancer incidence in children allows for a glimpse into factors that lead to cancer given that children aren’t likely to have risky lifestyles that put them at risk for cancer. They are, however, exposed to toxins in the air, food, and water at a greater rate than adults. They’re also exposed to these toxins in the womb.

Despite the 1984 enactment of the Illinois Health and Hazardous Substances Registry Act, designed to examine toxic chemicals in the workplace and environment, the environment is still neglected when determining cancer causes. Lung cancer, often attributed to cigarette smoke, is the leading cause of cancer deaths. However, most cancers can’t be traced back to smoking, and lung cancer among nonsmokers is quite high. The acknowledgment of possible environmental causes of cancer, however, is increasing. The National Children’s Study, launched in 2009, follows child development and the presence of contaminants in children’s environment from prenatal life to age 21. In addition, environmental oncology studies at university cancer centers are on the rise. Other factors coming to the forefront of cancer research—including the rising cancer incidence in children, the rising incidence among generations of adults, and attention to cancers that show rapid rates of increase—encompass a focus on environmental factors. Studying lymphoma, a cancer that exhibits rapid growth rates, is important because the lymph system can reveal cancer cells of all kinds.

Steingraber concludes the chapter by returning to her story of her friend Jeannie, who succumbed to cancer. In the medical papers Jeannie left behind, Steingraber found evidence of a potential link between environmental toxins (due to a 1980s fuel rod issue at a nuclear power plant) and a sharp increase in leukemia in Jeannie’s hometown in Massachusetts. However, this link was never substantiated.