Editorial: The sounds of silence

By: Tim Lougheed

Sixty years ago this fall, a woman dying of cancer published a book that would upend the discussion around the responsibility of governments and private companies toward the environment. Rachel Carson would only live another 18 months, but decided to spend much of that time promoting her book’s message to as many different public audiences as possible, even testifying to the Science Advisory Committee of US President John F. Kennedy. She would receive honours from organizations like the National Audubon Society and bitter rebuke from representatives of the chemical industry, who dismissed her as an unqualified hack.

In some ways she was just a hack, but perhaps in the best sense of the word. Her formal educational background was in marine biology, but she nurtured a talent for telling stories about science that would be accessible to lay readers. She covered a variety of topics, but the one that ultimately took centre stage was the post-war emergence of synthetic chemicals that were being used to eliminate insect pests. She became curious about the impact of these widely used agents, not just on the creatures they were intended to kill, but on other creatures that might get in the way — including us.

Her book, Silent Spring, examined one of the most prominent of these chemicals, dichlorodiphenyltrichloroethane, which became known as DDT. By the 1940s, it was commonly used in domestic settings such as people’s homes, where it was sprayed on walls to minimize the spread of diseases such as malaria and typhus by mosquitos. Such applications were indiscriminate, as few laws and regulations addressed the potential effects of human or animal exposure to DDT.

Scientists were paying attention, however, and Carson was paying attention to those who confidentially voiced concerns about the dangers of such pesticides. Even as many in government and industry offered unqualified reassurances about the safety of DDT, she began exploring the prospect that it was not a poison that conveniently targeted insects we did not like, but a hazardous pollutant that killed or compromised the health of any species coming into contact with it.

Silent Spring became a runaway hit when it appeared in 1962. The popular naturalist David Attenborough argued that its blunt message changed the scientific world in much the same way as Charles Darwin’s epic, Origin of Species. Critics, meanwhile, cast the book as a screed against the business of novel chemistry, if not a threat to progress and a rising standard of living.

But Carson did not completely reject the value of DDT as a means of controlling mosquito-borne diseases. Nor did she call for a ban on its use. Instead, she expressed her optimism about finding better ways of using such tools, if only those responsible for them would adopt a more critical perspective.

“Much of the necessary knowledge is now available, but we do not use it,” reads the text. “We train ecologists in our universities and even employ them in our government agencies, but we seldom take their advice. We allow chemical death rain to fall as though there were no alternative, whereas in fact there are many, and our ingenuity could soon discover more if given opportunity.”

Despite that call for rational compromise, Silent Spring had the remarkable effect of drawing battle lines that remain to this day, defining the hard edges of environmental activism and environmental regulation. We have Carson to thank for the creation of the US Environmental Protection Agency in 1970, and the beginning of unprecedented public oversight over all aspects of how industry affects the landscape and communities wherever it operates.

And, although she never asked for it, we have Carson to thank for a US ban on DDT in 1972, something many of her critics never forgave her for. That ban, which became global in 2004, is among the harshest of those battle lines, since DDT’s limited use is still among the most effective ways of controlling malaria in parts of the world where the disease is endemic.

The same year the international ban on DDT went into effect, one of the pesticide’s most prominent defenders went to his grave still railing against Silent Spring. J. Gordon Edwards, an entomology professor at San Jose University in California, had publicly eaten a spoonful of DDT in the early 1960s to demonstrate his conviction that it was far safer than Carson was insisting. When he died in 2004, the Journal of American Physicians and Surgeons published a paper based on his own extensive screed detailing the many technical failings of Silent Spring.

“The ban on DDT, founded on erroneous or fraudulent reports and imposed by one powerful bureaucrat, has caused millions of deaths, while sapping the strength and productivity of countless human beings in underdeveloped countries,” he concluded. “It is time for an honest appraisal and for immediate deployment of the best currently available means to control insect-borne diseases. This means DDT.”

It is remarkable how similarly Edwards’ rhetorical style matched Carson’s, something she might well have approved. Had she lived to defend her own legacy, she would probably have welcomed a scientific critique of her work. But it would not have swayed her overarching message, which was a much more fundamental call to remain critical of all claims — be they scientific, social, economic, or unabashedly political.

It is that clarion call that animates the most passionate of environmental critics today, much to the chagrin of those who might imagine a happier time when you could work with industrial scale products without having to explain to anyone what those products might be doing to customers, neighbours, or the odd bird that lands in the parking lot.

As inefficient and annoying as those requirements might be, we take for granted the many measures that have resulted from this constant attention to the environment. For more than 20 years, Canada has maintained the National Pollutant Release Inventory, a remarkable database any of us can search to learn more about what is coming out of the smoke stack in that factory near your home. Such a wealth of information would have been unthinkable to Carson and her peers in the early 1960s, but we know it to be just one facet of a massive government department dedicated to initiatives that would have dazzled her.

Even when it comes to those thorny debates over the use of agricultural agents to better feed our burgeoning population, subtle progress continues to be made. Perhaps too subtle, since much of it lacks any clarifying voice like Carson’s, to make the implications more accessible to lay audience.

One prominent example is the ongoing use of neonicotinoids, a highly effective class of pesticides that protects major crops like canola from chewing insects. This product has been tied to the death of bees that pollinate canola plants, prompting calls for a ban on their use, which have been enacted in Europe. Such bans have forced farmers to fall back on less sophisticated products, which can cause even more damage to other species, including birds or digging animals.

Still less fortunate is all too limited discussion of underlying causes for this problem. As part of DDT’s cultural legacy, the term “pesticide” conjures up images of crop spraying equipment being hauled across fields or aircraft dropping clouds of chemicals from the sky. However, these new agents function as a seed coating — a bottle of liquid, which farmers pour into a bucket of seed and stir around. The coating stays on the seed, protecting it from insects while the plant is growing.

That raises a key question: if this pesticide sticks to the seed, which is placed directly in the ground, how does a bee ever encounter it? There might be some residual molecules that make their way into the flowering plant, but the real culprit is much less obvious. The high pressure drills used in no-till planting, which shoot seeds quickly into the ground without disturbing the soil, have an air exhaust that can capture vapours that might be around the seeds. This outlet can inadvertently send neonicotinoids into the atmosphere, even though this has nothing to do with their intended effect.

Such an insight should be part of Carson’s cultural legacy in the 21^st century, where DDT might still have its place and we can save bees by convincing tractor manufacturers to tweak their design. These are hard choices, and nobody said they would be easy, especially not Carson herself. But she died defending the importance of talking about them.

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