Pesticides
America's
agriculture is 48 times more toxic than 25 years ago. Blame neonics
A new study shows
that the class of insecticides called neonicotinoids poses significant threats
to insects, soil and water
Kendra Klein and Anna Lappé
Wed 7 Aug 2019 11.00 BST Last modified on Wed 7 Aug 2019
19.55 BST
‘Neonics are not only considerably more toxic to insects
than other insecticides, they are far more persistent in the environment.’
Photograph: Alamy Stock Photo
More than 50 years ago, Rachel Carson warned of a “silent
spring”, the songs of robins and wood thrush silenced by toxic pesticides such
as DDT. Today, there is a new
pesticide specter: a class of insecticides called neonicotinoids. For years,
scientists have been raising the alarm about these bug killers, but a new study
reveals a more complete picture of the threat they pose to insect life.
First commercialized in the 1990s, neonicotinoids, or
neonics for short, are now the most widely used insecticides in the world.
They’re used on over 140 crops, from apples and almonds to spinach and rice.
Chemically similar to nicotine, they kill insects by attacking their nerve
cells.
Neonics were
pitched as an answer to pests’ increasing resistance to the reigning insecticides.
But in an effort to more effectively kill pests, we created an explosion in the
toxicity of agriculture not just for unwanted bugs but for the honeybees,
ladybugs, beetles and the vast abundance of other insects that sustain life on
Earth.
What we now know is that neonics are not only considerably
more toxic to insects than other insecticides, they are far more persistent in
the environment. While others break down within hours or days, neonics can
remain in soils, plants and waterways for months to years, killing insects long
after they’re applied and creating a compounding toxic burden.
Neonics can remain in
soils, plants and waterways for months to years, killing insects long after
they're applied
The new study, published in the science journal PLOS One,
designed a way to quantify this persistence and combine it with data on the
toxicity and total pounds used of neonics and other insecticides. For the first
time, we have a time-lapse of impact: we can compare year-to-year changes in
the toxicity of US agriculture for insects. The results? Since neonics were
first introduced 25 years ago, US agriculture has become 48 times more toxic to
insect life, and neonics are responsible for 92% of that surge in toxicity.
Looking at this toxic time-lapse, another interesting detail
emerges: there’s a dramatic increase in the toxic burden of US agriculture for
insects starting in the mid-2000s. That’s when beekeepers began reporting
significant losses of their hives. It’s also when the pesticide companies that
manufacture neonics, Bayer and Syngenta, found a lucrative new use for these
chemicals: coating the seeds of crops like corn and soy that are grown on
millions of acres across the country. These seed coatings now account for the
vast majority of neonic use in the US.
Neonics are “systemic”, meaning they are water soluble and
therefore taken up by the plant itself, making its nectar, pollen, and fruit –
all of it – toxic. Only about 5% of a seed coating is absorbed by the plant,
the remainder stays in the soil and can end up in rivers, lakes and drinking
water with its runoff causing harm to wildlife and, as emerging evidence shows,
to people.
This study comes on the heels of the first analysis of
global insect populations, which found 40% of species face extinction, with
near total insect loss possible by century’s end, driven in part by pesticides,
with neonics a particular concern.
An analysis of global
insect populations found 40% of species face extinction, with near total insect
loss possible by century's end
For all of this harm, farmers get few, if any, benefits from
neonic seed coatings. According to the US Environmental Protection Agency, they
provide “little or no overall benefits to soybean production”, though nearly
half of soybean seeds in the US are treated. Similar analyses have found the
same for corn, yet up to 100% of US corn seeds are treated.
All this risk without reward has led some regulators to take
action. The European Union voted to ban the worst neonics in 2018. But the US government has so far failed to
act. Chemical company lobbying can explain much of this inaction. Bayer,
maker of the most widely used neonics, spent an estimated $4.3m lobbying in the
US on behalf of its agricultural division in 2017.
Not only has the EPA stalled scientific review of neonics,
last year, the Fish and Wildlife Service reversed an Obama-era ban on use of
these dangerous insecticides in wildlife refuges. Congress could change this.
Democratic representative Earl Blumenauer’s Saving America’s Pollinators Act
would ban neonicotinoids and other systemic, pollinator-toxic insecticides. The
bill has 56 co-sponsors, but faces a major hurdle clearing the House
agriculture committee given that the chairman representative, Collin Peterson,
a Democrat from Minnesota, counts Bayer and the pesticide industry’s trade
association, Croplife America, among his top contributors.
Beyond a ban, we need a concerted effort to transition US
agriculture away from dependence on pesticides and toward ecological methods of
pest control. We already know how to do this. Research shows that organic farms
support up to 50% more pollinating species and help other beneficial insects
flourish. And by eliminating neonics and some 900 other active pesticide ingredients,
they protect human health, too.
More than five decades ago, Rachel Carson warned that the
war we are waging against nature with toxic pesticides is inevitably a war
against ourselves. That is as true today as it was then. For the sake of the
birds and bees – and all of us – this war must end.
Kendra Klein, PhD, is senior staff scientist at Friends of
the Earth US
Anna Lappé is the co-founder of two national food and
sustainability organizations and is working on a book on pesticides and our
food
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