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New Study Shows Minimal Pesticide Impact on Bees by Angela Logomasini of CEI.
"A recently released study claims
to have finally proven that certain pesticides are harming both
honeybees and wild bees, and news headlines have sounded the alarm. For
example, a Los Angeles Times headline
exclaims: “Field Tests Show how Pesticides can Wreak Havoc on
Honeybees,” Yet a closer look at the data indicates that’s not the case.
The study data shows that the chemicals in question—called
neonicotinoids or neonics—have very little measurable impact on bees,
and any impact can be managed.
Neonics are systemic pesticides, which means they can be applied to
seeds and are then absorbed into the plants. Accordingly, unlike sprayed
pesticides that affect any insects on the plant at treatment time, only
the crop-destroying insects that chew on the plants have significant
exposures. Bees can have trace exposures because they bring pollen and
nectar back to the hives. Accordingly, the study was designed to
measure traces of the chemicals found in hives and any resulting impacts
on bees.
Funded in part by two companies that make these chemicals—Syngenta
and Bayer CropScience—this recent study attempted to assess the impact
of the chemicals in real-life scenarios, rather than in a lab.
Accordingly, it involved field tests, measuring exposures after bees
foraged in oil seed rape (known as canola in the United States) crops in
Hungary, Germany, and the United Kingdom. The researchers discussed
their findings in an article for Science magazine, but the full dataset was made available to scientists at Syngenta and Bayer CropScience.
Syngenta’s scientist explained at a recent event hosted by the Science Media Centre in the UK:
This CEH paper does not present the full
set of data analysis conducted by CEH and reported to Syngenta for
honeybees. For example the pre-winter data analysis carried out by CEH
which showed that any effects reported during the flowering period had
disappeared (i.e. recovery), were not included in the paper. There were
in fact 258 separate honeybee statistical data analyses reported to
Syngenta by CEH. Out of these analyses, 238 resulted in no effect, 7
resulted in beneficial effects, 4 with insufficient data and only and 9
resulting in negative effects. The rules for statistical
significance allow for a 5% probability of generating random effects.
Therefore based on this internationally accepted statistical benchmark
and the 258 analysis CEH carried out, we could expect 13 random
results. Therefore the –ve and +ve results reported by CEH could easily
be random i.e. not real, and a conclusion of no effect of the neonics
reached. It should also be noted that the pollen and nectar residue
analysis reported by CEH in this paper indicated that circa 95% of the
time no neonic residues were measured, even in samples taken directly
from the treated crop. Therefore bees in these trials were hardly ever
exposed to any neonic residues.
That’s quite an amazing finding that 95 percent of the time there were no detectable levels of neonics in hives or pollen from. This indicates a very minimal exposures,
which should be considered a success. After all, the goal should be to
find products that help farmers produce food while keeping risks low,
and that does not mean risks will ever be zero. The simple reality is
that any farming activity will have environmental impacts, so the key is
managing them to maximize benefits and minimize unintended wildlife
impacts. So if bees are only exposed 5 percent of the time when a
chemical is used, that’s a very good result.
Moreover, within the 5 percent of the time that there was exposure,
the impacts were tiny and probably insignificant. The Hoover
Institution’s Dr. Henry I. Miller provides an excellent analysis of this
data in Forbes.
He points out that study showed that the overwhelming majority of the
258 analyses (97 percent) showed either no effect (94 percent) or beneficial effects (3 percent).
Only 3 percent of the analysis demonstrated adverse effects. Yet that
small sample of adverse finings has become the focus among the
researchers as well as all the news stories, which is absurd. “[T]he
authors are basing their study’s conclusions on a handful of outlier
results–effects so small that they could be occurring by chance–amid a
much larger amount of experimental data they generated that points to
precisely the opposite conclusions,” notes Miller.
The strongest conclusion that the researchers could draw as stated in the study abstract was that data “points to”
the conclusion that the chemicals “reduced capacity of bee species to
establish new populations in the year following exposure.” Yet all the
adverse impacts were found in Hungary and the UK; no problems were found
in Germany where hives were apparently healthier with less
disease-related problems.
One of the study’s authors, Ben Woodcock, explained
that the differences between countries suggests that healthier hives
are less susceptible to the chemicals. He explained that rather than
banning neonics, the solution lies in improving hive health through
better beekeeping practices and improved diets though the planting of
more diverse flowering food sources.
Woodcock points out that
“Neonicotinoids do have a vital role to play in food production. As
they can target particular insects they can be used in low dosages,
reducing the need for broad spectrum insecticide sprays. They are also
useful in controlling pests which have already developed some resistance
to other pesticides.”
Unfortunately, the headlines don’t focus on those aspects and instead
are being used to promote bans. Such hype in the past led European
Union officials to temporarily impose bans on neonics in 2013 and this
study may encourage them to make that ban permanent
despite the adverse impacts for agriculture. For example, earlier this
year, oilseed rape farmers in the UK petitioned the government to allow
emergency use of neonics because of serious crop damage, but they were denied.
Ironically, the bees are also suffering ill effects of the misguided
ban because farmers are forced to use more toxic pesticides. Matt Ridley
explains: “In Britain, for example, the study finds that farmers have
more than quadrupled the number of insecticide applications on oil-seed
rape (from 0.7 to 3.4 per growing season), but pest pressure has
increased.” Apparently, the older treatments don’t work as well either
and hence, farmers are seeing greater crop damage.
Clearly, policymakers need to look at a broader perspective. If they
care about both people and wildlife, they would look for balanced
policy. Neonics have an important role and as the data in this most
recent study shows, their impact on bees is negligible. And it’s clearly
better than many of the alternatives. So rather than expand regulation,
they need to eliminate the counter-productive ban they issued in 2013."
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