11/24/2023
From the Office of
Grass to Veggies
FOR
IMMEDIATE RELEASE
Contact:
James Lissy | info@grasstoveggies.com | www.grasstoveggies.com | Longmont, CO
Re:
Boulder County Proposed Integrated Weed Management Plan
Download PDF Version
 |
| Earthrise from the moon – Apollo 8 – Photo by Bill Anders. “The Earth from here is a grand oasis in the big vastness of space.” – Jim Lovell |
As
a resident of Boulder County, the county’s proposed integrated weed management
proposal is appalling due to its emphasis on using, over-using and unchecked
use of chemicals which pose a significant threat to human health, pollinators,
water quality, aquatic life, soil and overall health of the environment. The lack of pro-active notification to the
community regarding this plan, lack of emphasis on indigenous / regenerative
agriculture for weed control, lack of consideration of modern science and lack
of scientific monitoring when chemicals are used make this proposed plan highly
unacceptable.
I
understand that the County wants the easy button when it comes to weed
control. The County wants to be able to
suppress the undesirable weeds as easily and efficiently as possible. However, the effects that the chemicals have
on everything else in the environment is blatantly ignored in this proposed
plan. At the bottom of this letter, you
will find a list of scientific articles that walk you through the actual
effects that these chemicals have on the environment as a whole. While a lot of these chemicals do effectively
kill the targeted species and some are certainly more harmful than others, the
majority of these chemicals have drastic and unknown consequences on the rest
of the environment as a whole. These are
extremely important considerations since these chemicals can have negative
effects on desirable plants species, pollinators, soil health, water quality,
aquatic health, endangered species, and us humans. Not to mention that the increasing resistance
to chemicals in the targeted weed species has been noted in several studies
which hints at chemicals that are currently effective will likely not be
effective in the future.
As
you read through the actual scientific and independent research a few things
become abundantly clear. Governing
agencies and society as a whole generally consider these chemicals to be safe
until proven otherwise. Even after the
chemicals have been proven to not be safe, the new peer reviewed scientific
papers done by independent scientists with independent funding gets rejected
and ignored by governing agencies within the US, such as the Environmental
Protection Agency (EPA). The only
“science” that the EPA currently evaluates is what is submitted by the company
that manufactures the chemical when they first submit an application to the
EPA. These companies stand to make
billions of dollars in profit if their applications are approved by the EPA
which is an obvious and clear conflict of interest. Most governing bodies outside of the US peer
review submitted research to either verify or dismiss the submitted research
which makes governing bodies outside of the US currently much more reliable for
determining harm levels of chemicals.
The majority of these chemicals have adverse effects on plants, worms,
soil, fish, aquatic life, and seed production of desirable plants. These negative effects of chemicals are
normally not discovered until well after the wide use of the chemicals, making
the damage already done. Paper after
paper cites lacks of research or notes that more research is needed into
specific and potentially harmful aspects of chemical use. When research is done on effects of
pollinators, this research is usually limited to honey bees. This limited research is absurd for a few
notable reasons: Bees in general are not
the only pollinators and are only a portion of all overall pollinators. Honey bees are not native to the US and there
are a lot of native bee species in the US which are commonly referred to as
native bees. Native bees are extremely
important to the ecosystem since they have adapted to live here naturally,
without human assistance. Chemical
effects on native bees have not been researched. A lot of these native bees are solitary, do
not live in hives and live underground or in brush on the ground making them
more susceptible to the potential effects of chemicals. Furthermore, pollinators in general have a
wide range of foraging which also makes them more susceptible to chemical use
even if the chemicals are not sprayed directly on them. Chemical effects on soil and water health are
often overlooked and it is routinely discovered that chemicals once touted as
safe have drastic negative effects on soil and water health.
Based
on the factual findings of actual modern scientific research done by
independent scientists and the lack of adequate research into the potential
negative environmental effects noted by the majority of the scientific papers I
would like to propose the County adopt and implement the following into their
proposed weed management plan. The
County emphasizes and prioritizes indigenous / regenerative agriculture
practices above everything else. This
would include but would not be limited to: livestock grazing, reseeding native
plants, and controlled burns. The County
hires and collaborates with local indigenous communities, ranchers, farmers,
and local businesses who have vast and extensive knowledge in regenerative
agriculture to come up with the best solutions possible with a priority and
emphasis on community and environmental health.
The County does not implement the use of any chemical until the chemical
is scientifically proven safe for every aspect of the environment, aside from
the targeted species, by peer reviewed, independently funded research and
scientists. Notify the community via
pro-active outreach at least 90 days before a new chemical is scheduled to be
used by the County. The County establish
a way for community members to submit new research that has been done on
chemicals that are currently in-use by the County and the County halts all use
of the chemical in question until the concerns have been evaluated by an
independent, 3rd party scientist that is in no way shape or form
affiliated with the manufacturer of the chemical and is an expert in their
field. Aerial application is not allowed
in any way, shape or form due to the uncontrolled and broad nature of aerial
applications along with the large carbon footprint that aerial applications
have. Before any chemical use or
application of any kind, the county takes comprehensive soil, water, and air samples
of the direct and surrounding area that chemicals will be applied to. After chemical application, routine soil,
water and air samples of the direct and surrounding areas are routinely taken
and changes monitored by an independent, 3rd party that is not
affiliated with the chemical manufacturer in any way shape or form. All samples, results, and analysis are
property of the public and made public as soon as the sample results are
available and public release is not to be delayed for any reason. This routine sampling shall be done for a
period of at least 2 years since the last chemical application on each
parcel. The County very clearly
implement measures laid out in the Colorado Pesticides Act to ensure that state
regulations on pesticide use is being followed by County employees and that
proper labelling of the application area is occurring so the public is aware
what chemicals have been applied and when and in what dosage along with the
complete history of chemical use by the County being an easily accessible
public record. The County establish a
new position or office of Ombudsman – the purpose of which is to receive,
evaluate, and investigate complaints from the general public regarding County
practices, procedures, implementation, etc.
This position or office would be an intermediary between the County and
the public and they would take all points of view into consideration and would
have legal authority to implement change at the highest level, if needed, to
protect the health of the community and the environment.
In
addition to implementing the measures listed above directly into the Integrated
Weed Management plan the County needs to implement additional measures to
protect the community. Matters,
proposals or issues that are deemed potential public health threats / issues
should trigger the County to send pro-active outreach to every known citizen of
the County to notify them of the potential public health issue and to illicit
feedback. This would include, but not be
limited to, the County asking each City to put a notice in each city newsletter
that already gets mailed out to each County resident each month. The County should then hold several open
houses at varying days and times, including weekends, do not require an RSVP
and do not have attendance limitations for the purpose of having community
conversations regarding the public health issue. The open houses shall be run by the new
position or office of the Ombudsman to ensure an unbiased and nonpartisan
approach and conversation. The Ombusdamn
would also implement non-biased surveys to gather as much public feedback as
possible without trying to steer the public towards a specific agenda. Additionally, matters affecting public health
should be required to be put to a public vote so the voice of each and every
resident can be heard regarding the issue.
These
measures would put an emphasis on protecting the health of the community and
the environment which is of the utmost importance. If we do not have our health or if the
environment is not healthy from unintended consequences, then we as a community
have nothing.
Without
further ado, here are links to 46 scientific articles so you can read through
them and come to your own conclusions which should ultimately lead to better
overall conversations in the community that are focused on the health of the
community and the health of the environment and how we can work with nature
instead of against it. In addition to
the scientific articles below, the documentaries Into the Weeds and The
People vs. Agent Orange do in-depth dives into glyphosate and 2-4-D
respectively. The County revamping the
weed management plan has potential to be an unbelievable force for good and
template for other communities that is based on community input /
conversations, science, health, and environmental health. I should hope that we can all agree that each
of those aspects should be of the utmost importance to our society as a whole.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4947579/
The
industrialization of the agricultural sector has increased the chemical burden
on natural ecosystems. Pesticides are agrochemicals used in agricultural lands,
public health programs, and urban green areas in order to protect plants and
humans from various diseases. However, due to their known ability to cause a
large number of negative health and environmental effects, their side effects
can be an important environmental health risk factor. The urgent need for a
more sustainable and ecological approach has produced many innovative ideas,
among them agriculture reforms and food production implementing sustainable
practice evolving to food sovereignty. It is more obvious than ever that the
society needs the implementation of a new agricultural concept regarding food
production, which is safer for man and the environment, and to this end, steps
such as the declaration of Nyéléni have been taken.
Many
of the pesticides have been associated with health and environmental issues, and
the agricultural use of certain pesticides has been abandoned. Exposure to pesticides can be through contact
with the skin, ingestion, or inhalation. The type of pesticide, the duration
and route of exposure, and the individual health status (e.g., nutritional
deficiencies and healthy/damaged skin) are determining factors in the possible
health outcome. Within a human or animal body, pesticides may be metabolized,
excreted, stored, or bioaccumulated in body fat. The numerous negative health
effects that have been associated with chemical pesticides include, among other
effects, dermatological, gastrointestinal, neurological, carcinogenic,
respiratory, reproductive, and endocrine effects. Furthermore, high
occupational, accidental, or intentional exposure to pesticides can result in
hospitalization and death.
Current
agriculture has to deal with important factors, such as population growth, food
security, health risks from chemical pesticides, pesticide resistance,
degradation of the natural environment, and climate change. In recent years,
some new concepts regarding agriculture and food production have appeared. A
concept as such is climate-smart agriculture that seeks solutions in the new
context of climate change. Another major ongoing controversy exists between the
advocates and the opponents of genetically engineered pesticide-resistant
plants, regarding not only their safety but also their impact on pesticide use.
Furthermore,
the real-life chronic exposure to mixture of pesticides with possible additive
or synergistic effects requires an in depth research. The underlying scientific
uncertainty, the exposure of vulnerable groups and the fact that there are
numerous possible mixtures reveal the real complex character of the problem. The combination of substances with probably
carcinogenic or endocrine-disrupting effects may produce unknown adverse health
effects. Therefore, the determination of “safe” levels of exposure to single
pesticides may underestimate the real health effects, ignoring also the chronic
exposure to multiple chemical substances.
Taking
into consideration the health and environmental effects of chemical pesticides,
it is clear that the need for a new concept in agriculture is urgent. This new
concept must be based on a drastic reduction in the application of chemical
pesticides, and can result in health, environmental, and economic benefits as
it is also envisaged in European Common Agricultural Policy (CAP).
We
believe in developing pesticide-free zones by implementing a total ban at local
level and in urban green spaces is easily achievable.
https://www.frontiersin.org/articles/10.3389/fenvs.2021.643847/full
Agricultural
pesticide use and its associated environmental harms is widespread throughout
much of the world. Efforts to mitigate this harm have largely been focused on
reducing pesticide contamination of the water and air, as runoff and pesticide
drift are the most significant sources of offsite pesticide movement. Yet
pesticide contamination of the soil can also result in environmental harm.
Pesticides are often applied directly to soil as drenches and granules and
increasingly in the form of seed coatings, making it important to understand
how pesticides impact soil ecosystems. Soils contain an abundance of
biologically diverse organisms that perform many important functions such as
nutrient cycling, soil structure maintenance, carbon transformation, and the
regulation of pests and diseases. Many terrestrial invertebrates have declined
in recent decades. Habitat loss and agrichemical pollution due to agricultural
intensification have been identified as major driving factors.
Our
review indicates that pesticides of all types pose a clear hazard to soil
invertebrates. Negative effects are evident in both lab and field studies,
across all studied pesticide classes, and in a wide variety of soil organisms
and endpoints. The prevalence of negative effects in our results
underscores the need for soil organisms to be represented in any risk analysis
of a pesticide that has the potential to contaminate soil, and for any
significant risk to be mitigated in a way that will specifically reduce harm to
soil organisms and to the many important ecosystem services they provide.
https://www.sciencedirect.com/science/article/pii/S2667010021001281
Glyphosate is an extensively used herbicide globally. Its use
dates back to 1970s with increasing numbers over the years. It is an effective
weed killer but since it parallelly destroys non-target crops, its use during
initial days was restricted.
Over years of extensive usage, many issues related to toxicity,
carcinogenicity and GE varieties cropped up. Many researchers studied the
toxicological characteristics, health impacts, environmental exposures and
ecological impacts of glyphosate and Glyphosate-based herbicides. Many
international agencies assessed its carcinogenic potential and grouped and
regrouped it based on conclusions of various studies. As an outcome of many
studies, an important aspect of toxicity of adjuvants used for technical formulations
of glyphosate surfaced and gave a better understanding of its overall toxicity.
In interaction with water, glyphosate rapidly converts into its
primary metabolite, i.e., AMPA, that holds most of its precursor's harmful
properties and becomes far more persistent, such that its half-life lasts
between 76 and 240 days
Glyphosate, as stated in the usage guidelines and the harmful
clauses mentioned in the health data sheet, should not be released in the
environment since it is harmful to marine organisms, with long-term impact
studied the effect of glyphosate addition on plant tissues of Lemna
minor (common duckweed) which resulted in reduced yield and growth,
prevents the synthesis of carotenoids and
chlorophyll a and b, and declines the photosystem II photochemical functions.
Glyphosate transforms into AMPA as soon as it comes into contact
with water while maintaining toxic aspects of its precursor.
Glyphosate can interfere with water-soluble organic matter, clay
particles, and colloidal iron oxides.
This connection could therefore contribute to colloidal associated
transportation of glyphosate. Various
concentrations of the residues were found in ground and surface waters.
Usually, groundwater has been utilized as the essential source of drinking water supply.
There are several reports which suggest that the water supplies in areas having
intensive agricultural activities might be at high risk of glyphosate
contamination
The study thus indicated that inhalation of the said herbicides
may cause damage to DNA in exposed humans.
When examining the influence of Roundup
containing glyphosate on aromatase, the enzyme involved in the development of
oestrogen, at nontoxic levels, it was noted that glyphosate interferes with the
levels of aromatase and mRNA and thus has both endocrinal and toxic effects The
research suggests that Roundup containing glyphosate is lethal to placental
cells of the human within 18 hours of exposure, at amounts lower than those for
agricultural use
https://www.nature.com/articles/s41598-020-67025-2
Plant
communities in field edges, fallow fields, and other semi-natural habitats of
agricultural landscapes may be at significant ecotoxicological risk from
herbicides applied to nearby crop fields. In agricultural landscapes, field
margins, fallow fields, and other semi-natural habitats are often the only
remaining habitat for wild plant species and support diverse plant communities
that help sustain pollinators, predators, and beneficial arthropods. Previous
studies have indicated that herbicides, even at low concentrations, adversely
affect plant communities, causing a decline in forb cover and reduced the
flowering of key species and a reduction in the frequencies of certain species.
Our data on plant species diversity and community composition of a fallow field
support these findings.
Herbicides
may not be an important factor in changing the functional composition of plant
communities in the short term, but the long-term cumulative effects of
herbicides on the functional composition and structure of plant communities in
agricultural ecosystems need to be taken seriously
https://www.sciencedirect.com/science/article/abs/pii/S0048969717330279
The
herbicide glyphosate, N-(phosphonomethyl) glycine, has been used extensively in
the past 40 years, under the assumption that side effects were minimal.
However, in recent years, concerns have increased worldwide about the potential
wide ranging direct and indirect health effects of the large scale use of
glyphosate. In 2015, the World Health Organization reclassified glyphosate as
probably carcinogenic to humans.
there
are animal data raising the possibility of health effects associated with
chronic, ultra-low doses related to accumulation of these compounds in the
environment.
Intensive glyphosate use has led to the selection of
glyphosate-resistant weeds and microorganisms.
Shifts in microbial compositions due to selective pressure by glyphosate may
have contributed to the proliferation of plant and animal pathogens.
https://www.intechopen.com/chapters/70451
It
is scientifically proven that herbicides cause infertility, kidney problems,
endocrine disruption, apoptosis, cytotoxicity, and neurotoxic effects. Such
diseases impact the quality of those affected, and naturally the contaminated
environment negatively affects human health.
Sixty
percent of agrochemicals are used in the soil, and the others drain into the
ground polluting the water supply; these chemicals are toxic for living
organisms as they are absorbed by plants and successively accumulate in human
tissue through biomagnifications of the food chain, causing human health and
environment concerns. Chemical pollutants are a serious and growing global
problem.
several
studies have shown that herbicides and their derivative compounds contaminate
natural resources such as water and soil, for example, aminomethylphosphonic
acid (AMPA), a secondary compound of glyphosate, can persist for several years
in the soil.
People
who have been exposed to herbicides occupationally, or by eating foods or
liquids containing herbicide residue, or for that matter inhaled
herbicide-contaminated air, have experience a broad range of chronic health
effects, including impaired neurobehavioral function (e.g., cognitive and
behavioral disorders), Alzheimer’s and Parkinson’s diseases, hormone
disruption, asthma, allergies, hypersensitivity, obesity, diabetes, hepatic
lesions, kidney failure, multiple sclerosis, and cancer
https://www.mcgill.ca/newsroom/channels/news/widely-used-weed-killer-harming-biodiversity-320906
One
of the world’s most widely used glyphosate-based herbicides, Roundup, can
trigger loss of biodiversity, making ecosystems more vulnerable to pollution
and climate change
The
widespread use of Roundup on farms has sparked concerns over potential health
and environmental effects globally. Since the 1990s use of the herbicide
boomed, as the farming industry adopted “Roundup Ready” genetically modified
crop seeds that are resistant to the herbicide. “Farmers spray their corn and
soy fields to eliminate weeds and boost production, but this has led to
glyphosate leaching into the surrounding environment. In Quebec, for example,
traces of glyphosate have been found in Montérégie rivers,” says Andrew
Gonzalez, a McGill biology professor and Liber Ero Chair in Conservation
Biology.
“We
observed significant loss of biodiversity in communities contaminated with
glyphosate. This could have a profound impact on the proper functioning of
ecosystems and lower the chance that they can adapt to new pollutants or
stressors. This is particularly concerning as many ecosystems are grappling
with the increasing threat of pollution and climate change,” says Gonzalez.
https://www.nature.com/articles/s41559-020-1134-5
https://www.researchgate.net/publication/343878200_Effect_of_Herbicides_on_Living_Organisms_in_The_Ecosystem_and_Available_Alternative_Control_Methods
the
side effects caused by the wide and irrational use of herbicides threaten the
environment and human health. Although herbicides are the least harmful among
pesticides, many studies have shown the serious negative effects of herbicides
on the environment and human health. Every year a list of herbicides that cause
cancer or leave large residues in the soil and water are published. However,
many herbicides have been banned, but only after they have been used in tons
and causing environmental pollution. The chemical structure of herbicides
degrades quite slowly in nature, which causes its accumulation in the soil and
the environment. The effects of these herbicides have reached rivers, lakes,
seas and oceans. Also, the effect of chemically degradation herbicides on
living organisms under different environmental conditions is still unknown.
The
effect of herbicides on non-target plants Herbicides, especially broad-spectrum
herbicides, affect plant biological
diversity and damage
environmental balance. In addition to the possibility of killing
crops, herbicides can reduce plant yield and increase susceptibility to
diseases. For example, glyphosate significantly increases the severity of
various plant diseases, and lead to weakening plant capacity to resist against
pathogens, and immobilizes soil and plant nutrients
https://www.sydney.edu.au/news-opinion/news/2023/07/13/global-analysis-shows-how-pesticides-leach-into-the-environment.html
A
University of Sydney led study published today in Nature has revealed the
chemical odyssey pesticides embark upon after their initial agricultural
application, with environmental consequences for a range of ecosystems.
A
global study published today in Nature, which analysed the geographic
distribution of 92 of the most commonly used agricultural pesticides, found
that approximately 70,000 tonnes of potentially harmful chemicals leach into
aquifers each year, impacting ecosystems and freshwater resources.
Associate
Professor Federico Maggi, the study’s lead author from the University of
Sydney’s School of Civil Engineering, said: “Our study has revealed that
pesticides wander far from their original source. In many cases these chemicals
end up a long way downstream and often, though in much smaller amounts, all the
way to the ocean.”
The
study showed that about 80 percent of applied pesticides degrade into daughter
molecules – or byproducts – into soil surrounding crops.
This
degradation of pesticides often occurs as a ‘cascade’ of molecules into the
surrounding environment, which can persist in the environment for a long time
and can be just as harmful as the parent molecule or applied pesticide. One
such example is glyphosate. Although it is highly degradable, it breaks down
into a molecule known as AMPA that is both highly persistent and toxic,” said
Associate Professor Maggi.
Associate
Professor Maggi last week co-authored a separate paper in Nature Ecology and
Evolution that outlined recommendations to reduce pesticide use, including
calling for a reliable set of indicators and improved monitoring.
He
and the paper’s co-authors argue that targets for lowering pesticide pollution
should be focused on decreasing risk, including reducing amounts and toxicity,
because some organisms are at high risk from very toxic pesticides, even when
used in low quantities.
https://www.nature.com/articles/s41586-023-06296-x
https://www.washington.edu/news/2019/02/13/uw-study-exposure-to-chemical-in-roundup-increases-risk-for-cancer/
Exposure
to glyphosate — the world’s most widely used, broad-spectrum herbicide and the
primary ingredient in the weedkiller Roundup — increases the risk of some
cancers by more than 40 percent, according to new research from the University
of Washington.
Various
reviews and international assessments have come to different conclusions about
whether glyphosate leads to cancer in humans.
The
research team conducted an updated meta-analysis — a comprehensive review of
existing literature — and focused on the most highly exposed groups in each
study. They found that the link between glyphosate and Non-Hodgkin Lymphoma is
stronger than previously reported.
“Our
analysis focused on providing the best possible answer to the question of
whether or not glyphosate is carcinogenic,” said senior author Lianne Sheppard,
a professor in the UW departments of Environmental & Occupational Health
Sciences and Biostatistics. “As a result of this research, I am even more
convinced that it is.”
By
examining epidemiologic studies published between 2001 and 2018, the team
determined that exposure to glyphosate may increase the risk of Non-Hodgkin
Lymphoma by as much as 41 percent. The authors focused their review on
epidemiological research in humans but also considered the evidence from
laboratory animals.
“This
research provides the most up-to-date analysis of glyphosate and its link with
Non-Hodgkin Lymphoma, incorporating a 2018 study of more than 54,000 people who
work as licensed pesticide applicators,” said co-author Rachel Shaffer, a UW
doctoral student in the Department of Environmental & Occupational Health
Sciences.
“These
findings are aligned with a prior assessment from the International Agency for
Research on Cancer, which classified glyphosate as a ‘probable human
carcinogen’ in 2015,” Shaffer said.
https://pubmed.ncbi.nlm.nih.gov/31342895/
Glyphosate
is the most widely used broad-spectrum systemic herbicide in the world. Recent
evaluations of the carcinogenic potential of glyphosate-based herbicides (GBHs)
by various regional, national, and international agencies have engendered
controversy. We investigated whether there was an association between high
cumulative exposures to GBHs and increased risk of non-Hodgkin lymphoma (NHL)
in humans. We conducted a new meta-analysis that includes the most recent
update of the Agricultural Health Study (AHS) cohort published in 2018 along
with five case-control studies. Using the highest exposure groups when
available in each study, we report the overall meta-relative risk (meta-RR) of
NHL in GBH-exposed individuals was increased by 41% (meta-RR = 1.41, 95%
confidence interval, CI: 1.13-1.75). For comparison, we also performed a
secondary meta-analysis using high-exposure groups with the earlier AHS (2005),
and we calculated a meta-RR for NHL of 1.45 (95% CI: 1.11-1.91), which was
higher than the meta-RRs reported previously. Multiple sensitivity tests
conducted to assess the validity of our findings did not reveal meaningful
differences from our primary estimated meta-RR. To contextualize our findings
of an increased NHL risk in individuals with high GBH exposure, we reviewed
publicly available animal and mechanistic studies related to lymphoma. We
documented further support from studies of malignant lymphoma incidence in mice
treated with pure glyphosate, as well as potential links between glyphosate /
GBH exposure and immunosuppression, endocrine disruption, and genetic
alterations that are commonly associated with NHL or lymphomagenesis. Overall,
in accordance with findings from experimental animal and mechanistic studies,
our current meta-analysis of human epidemiological studies suggests a
compelling link between exposures to GBHs and increased risk for NHL.
https://www.iarc.who.int/wp-content/uploads/2018/07/MonographVolume112-1.pdf
The
herbicide glyphosate and the insecticides malathion and diazinon were
classified as probably
carcinogenic
to humans.
https://www.iarc.who.int/wp-content/uploads/2018/07/pr236_E.pdf
The
herbicide 2,4-D was classified as possibly carcinogenic to humans (Group 2B),
based on inadequate evidence in humans and limited evidence in experimental
animals. There is strong evidence that 2,4-D induces oxidative stress, a
mechanism that can operate in humans, and moderate evidence that 2,4-D causes
immunosuppression, based on in vivo and in vitro studies
https://www.sciencedirect.com/science/article/pii/S0045653519322556
Once
2,4-D is applied directly on the soil or sprayed on the crops, it easily
reaches water bodies. Being a polar
molecule, 2,4-D and its ester and amines are quite mobile in aqueous systems
because of its acidic carboxyl group (pKa = 2.8) and low soil adsorption that
may be the reason for its widespread occurrence in the environment. In addition, it can reach the water bodies by
surface runoff or through infiltration, leaching and soil percolation, becoming
an environmental and human health problem.
It is also noteworthy that 2,4-D is a moderately persistent substance in
the environment, with a half-life between 20 and 312 days, depending on
environmental conditions.
Studies
have demonstrated the bioaccumulation capacity of this herbicide in non-target
organisms, exposed for a short period of time. Regarding the post-2,4-D
exposure effects in different organisms, studies have shown endocrine
disruption, reproductive disorders, genetic alterations and carcinogenic
effects. In humans, 2,4-D has been
associated with the development of Parkinson’s neurodegenerative disease and
autism.
https://www.sciencedirect.com/science/article/abs/pii/S0160412017315313
The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) is applied
directly to aquatic and conventional farming systems to control weeds, and is
among the most widely distributed pollutants in the environment. Non-target
organisms are exposed to 2,4-D via several ways, which could produce toxic
effects depending on the dose, frequency of exposure, and the host factors that
influence susceptibility and sensitivity. An increasing number of experimental
evidences have shown concerns about its presence/detection in the environment,
because several investigations have pointed out its potential lethal effects on
non-target organisms.
The salt and ester formulations of 2,4-D are derived from the
parent acid molecule. The dimethyl-amine salt (DMA) and 2-ethlhexyl ester (EHE)
are most commonly used formulations accounts of approximately 90 to 95% of the
total use across the world. Additionally, over 1500 herbicide products contain
2,4-D as an active ingredient and it was also a part of Agent Orange, the
herbicide widely used during the Vietnam war.
2,4-D is a moderately persistent chemical with a half-life (t1/2)
between 20 and 312 days depending upon the environmental conditions. The herbicide is directly applied onto soil or
sprayed over crops, and from there, often reaches superficial waters and
sediments. Due to low adsorption
coefficients and high solubility in water, 2,4-D has often been detected in
surface and ground water, which means an important environmental problem and
health hazard. About 91.7% of 2,4-D
eventually end up in water. This contamination threatens the life of exposed
vegetation and animals. Additionally, herbicides are also carried by runoff
into the local river systems, thereby threatening the health of aquatic life as
well. Unfortunately, 2,4-D has non-specific weed targets. It can reduce growth
rates, induce reproductive problems, and produce changes in appearance or
behavior, or could cause death of non-target species, including plants, animals
and microorganisms. It is also known as endocrine disruptors, affecting developmental
processes even at low concentrations
https://ehjournal.biomedcentral.com/articles/10.1186/s12940-021-00815-x
Of
the 14,395 participants included in the study, 4681 (32.5%) had urine 2,4-D
levels above the dichotomization threshold. The frequency of participants with
high 2,4-D levels increased significantly (p < .0001), from a low of 17.1%
in 2001–2002 to a high of 39.6% in 2011–2012. The adjusted odds of high urinary
2,4-D concentrations associated with 2,4-D agricultural use (per ten million
pounds applied) was 2.268 (95% CI: 1.709, 3.009). Children ages 6–11 years (n
= 2288) had 2.1 times higher odds of having high 2,4-D urinary concentrations
compared to participants aged 20–59 years. Women of childbearing age (age
20–44 years) (n = 2172) had 1.85 times higher odds than men of the same age.
Agricultural
use of 2,4-D has increased substantially from a low point in 2002 and it is
predicted to increase further in the coming decade. Because increasing use is
likely to increase population level exposures, the associations seen here
between 2,4-D crop application and biomonitoring levels require focused
biomonitoring and epidemiological evaluation to determine the extent to which
rising use and exposures cause adverse health outcomes among vulnerable
populations (particularly children and women of childbearing age) and highly
exposed individuals (farmers, other herbicide applicators, and their families).
https://pubmed.ncbi.nlm.nih.gov/21413141/
The herbicide aminopyralid provides foliar and
soil residual weed control and increases forage production in bahiagrass
pastures; however, the soil residual activity of aminopyralid makes carryover
injury likely in subsequent sensitive vegetable crops.
The
crops included in this research were negatively affected by aminopyralid at
soil concentrations less than the limit of quantitation (0.2 µg kg(-1) )
https://pubmed.ncbi.nlm.nih.gov/26313564/
Microbial
community diversity was moderately impacted by herbicide treatment
https://www.sciencedirect.com/topics/medicine-and-dentistry/chlorsulfuron
Currently,
the European Commission has decided to withdraw this substance from the market
as a result of the European Green Deal and due to chlorsulfuron's risk analysis
assessment.
https://efsa.onlinelibrary.wiley.com/doi/pdf/10.2903/j.efsa.2009.201r
The
compound IN-A40972 was concluded to be a relevant groundwater metabolite and a
relevant impurity. Based on the available information, there is no sufficient
evidence demonstrating the absence of carcinogenic properties.
The
metabolite IN-A4097 which was found in the metabolism studies was regarded as
toxicologically relevant.
Based
on the results of laboratory degradation studies published in the scientific
literature, the applicant also claimed
that a strong positive correlation was found between soil pH and half life of
chlorsulfuron in soil.
The
formulated product (“Chlorsulfuron 75 WG”) was tested on algae and aquatic
plants, showing a similar toxicity as the active substance, based on the
content of the active substance.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7660157/#:~:text=In%20a%20large%20(n%20%3D%2049,of%20up%20to%2020%20years.
In
a large (n = 49 922) prospective US cohort of pesticide applicators, dicamba
was associated with increased risk of liver and intrahepatic bile duct cancer. This association was robust to exposure lags
of up to 20 years.
In
a large prospective cohort, use of the herbicide dicamba was associated with
increased risk of liver and intrahepatic bile duct cancers. Dicamba use was
also inversely associated with myeloid leukaemia. Elevated risk of CLL was
associated with high dicamba exposure, but this association was only observed
in unlagged analyses. We additionally observed associations with tonsil cancer,
lymphocytic leukaemia and MCL
https://www.sciencedirect.com/topics/chemistry/fluroxypyr
However,
because it can pollute water, especially in the case of permeable soils and
near-surface groundwater levels, it can be applied only at a certain distance
(buffer zone) from lakes and streams.
These
compounds decompose partly by photodegradation and partly by microbial
pathways, but much more slowly than phenoxyacetic acids and benzoic acids.
Their half-lives in soil are 30–90 days. The degradation product of triclopyr
is persistent in soil for up to a year.
Solubility in water and thus susceptibility to water erosion or
leaching is high for atrazine, fluroxypyr, glyphosate, and metamitron,
Few
long-term studies on the fate of herbicides in soil have been done.
Besides
a herbicide’s chemical properties, its fate in soil depends on several
parameters. It can interact strongly with soil components by forming complexes
with metal ions in solution, and by being adsorbed on soil particles, including
clay minerals. An early laboratory study
found that the rate of degradation for three dinitroanilines was directly
correlated with soil temperature and moisture content. A compound may adsorb onto clay particles and
soil organic matter and remain unchanged for varying lengths of time
https://pubmed.ncbi.nlm.nih.gov/23128745/
The
half-life of fluroxypyr in soil samples ranged between 28 and 78 d. An
estimated mean 48.6 ± 20% of the fluroxypyr was converted into F-P and 8.0 ± 2%
into F-MP. The main metabolite, F-P, was rapidly degraded, with an average
half-life of 10 ± 5 d. However, F-MP was not degraded to a significant degree
in any sample, resulting in slowly increasing concentrations throughout the
experiment. This pattern of relatively rapid degradation of F-P and slow
accumulation of F-MP was also observed in the field. The persistent nature of F-MP
may be of concern if fluroxypyr is used repeatedly at the same location.
Fluroxypyr was detected in the groundwater beneath the track at all three
locations studied in concentrations exceeding the EU limit of 0.1 μg L for
pesticides in drinking water, and F-P was detected in the groundwater at two of
three locations. The most important factor controlling fluroxypyr degradation
rate in soil was the soil water content, which modulated microbial activity and
presumably also fluroxypyr availability to microorganisms.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6289906/
However,
it is possible that exposure to imazamox at low doses, via contaminated water,
over a prolonged period of time may cause a change in cellular structure and
function, even if it is not toxic at high doses.
https://pubmed.ncbi.nlm.nih.gov/24108543/
Imazapyr
has a high potential for leaching into groundwater because it is highly
water-soluble, persistent in soil, and only weakly sorbed by soils.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4423937/
Indaziflam,
a broad-spectrum, pre-emergence herbicide was the focus of a field
investigation conducted after the identification of sporadic injury symptoms on
the pecan trees a few months after the application.
Indaziflam
is classified as moderately mobile in the soil, however its breakdown products
(indaziflam-carboxylic acid, fluoroethyldiaminotriazine and
fluoroethyltriazinanedione) are more mobile [2]. The water solubility of
indaziflam is 0.0028 g/L at 20°C and its organic carbon sorption coefficient
(Koc) is <1,000 mL/g [2, 4].
Based
on the observed injuries of the ryegrass (Lolium multiflorum) planted in the
columns, indaziflam was reported to leach to 30 cm depth. Jhala et al. [8]
reported that the leaching depth of indaziflam is positively correlated with
the application rate and the amount of rainfall.
https://www.sciencedirect.com/science/article/abs/pii/S0098847221003361
the
extensive application of quinclorac has resulted in the evolution of resistant
plants, the frequent detection in the environment, and the hazard to non-target
organisms.
Accompanied
with the extensive use of herbicides, weed control has become difficult owing
to the evolution of herbicide resistance
As
one of the most important model organism, fish has long been employed for
examining the toxicity of pollutants in the aquatic environment (Fig. 5). For
silver catfish, 395 mg/L of quinclorac could lead to the deaths of 50%
population in the 96 h short term
The
potential hazard of quinclorac is originated from not only its toxicity to
non-target organisms but also its slow degradation in the environment
https://www.sciencedirect.com/topics/earth-and-planetary-sciences/aminocyclopyrachlor
Worldwide,
more than 30 weed species have evolved resistance to auxinic herbicides. Not
much is known about the mechanisms of resistance for most of these. The fact
that a significant number of the resistant weed biotypes have multiple
resistances to unrelated herbicides suggests that metabolic degradation is a
common mechanism of resistance.
Pesticides
are one of the highly persistent group of chemicals in the soil environment.
The excessive usage of pesticides leads to the formation of pesticide-based
soil contaminants.
https://bioone.org/journals/invasive-plant-science-and-management/volume-7/issue-4/IPSM-D-13-00097.1/Effects-of-Aminocyclopyrachlor-Herbicide-on-Downy-Brome-Bromus-tectorum-Seed/10.1614/IPSM-D-13-00097.1.short
No
published data exist on the effect of aminocyclopyrachlor on seed production of
desirable perennial grasses in natural ecosystems, thereby suggesting the need
for further research.
How
aminocyclopyrachlor will affect plant community composition may be difficult to
predict, because this herbicide also affects native forbs and shrubs, and may
reduce seed production of desired, perennial grasses. Further field testing is
needed to assess the effects of aminocyclopyrachlor on long-term changes in
plant community composition.
https://www.mdpi.com/2073-4395/8/1/1
Aminocyclopyrachlor
is an herbicide that belongs to the new class of chemicals known as the
pyrimidine carboxylic acids, which are used to control broadleaf weeds and
brush. However, the environmental behavior and fate of aminocyclopyrachlor are
not fully understood. The aim of the present study was thus to evaluate the
mineralization, extractable residue and bound residue formation of
aminocyclopyrachlor in three tropical soils with different physico-chemical
properties. 14C-labeled [pyrimidine-2-14C] aminocyclopyrachlor was used to
assess the fate of this herbicide in soil placed in biometer culture flasks.
Total mineralization (accumulated 14CO2) of aminocyclopyrachlor was found to be
<10% in all soils, decreasing in the following order: Oxisol—Typic Hapludox
(clay) > Oxisol—Typic Hapludox (loamy sand) > Plinthosol—Petric (sandy
clay). Overall, constant rate of mineralization (k) values for all soils were
very low (0.00050% to 0.00079% 14CO2 day−1), with mineralization half-life
times (MT50) consequently very high (877 to 1376 days), suggesting potential
long persistence in soil. The amount of extractable residues decreased from
~31% to 50% in all soils after 126 days of incubation, indicating an increase
in bound residue formation from ~5.0- to 7.5-fold compared to evaluation
immediately after herbicide application, suggesting that degradation herbicide
is involved in the formation of bound residues. Extractable residues are
important factors that control mineralization and bound residue formation from
aminocyclopyrachlor in the soil. The present study is the first to assess the
fate, distribution, and formation of bound residues of aminocyclopyrachlor in
soils. Aminocyclopyrachlor residues were predominantly associated with the OM
and clay contents of soil. This effect of soil physico-chemical properties
should be considered in environmental risk assessment of aminocyclopyrachlor
and its application in the field for weed control.
https://efsa.onlinelibrary.wiley.com/doi/full/10.2903/j.efsa.2018.5389#:~:text=Low%20acute%20toxicity%20was%20observed,observed%20adverse%20effect%20level%20(LOAEL)
The
data available on environmental fate and behaviour are sufficient to carry out
the required environmental exposure assessments at EU level for the
representative uses, with the notable exception that information is missing
regarding the effect of the water treatment process chlorination on the nature
of the residues that might be present in surface water, when surface water is
abstracted for drinking water. Consequently, the consumer risk assessment from
the consumption of drinking water could not be finalised. The potential for
groundwater exposure by the active substance clopyralid above the parametric
drinking water limit of 0.1 μg/L consequent to the uses assessed, was indicated
to be high in up to six out of nine FOCUS groundwater scenarios for the
representative use on winter cereals and up to three out of nine of these
scenarios for the representative use on grassland.
The
risk to aquatic organisms, earthworms and non-target plants was assessed as low
for exposure to clopyralid, but needs to be further assessed at Member State
level for the formulation.
data
gaps for description and validation data for the analytical method used in
developmental toxicity study in rats and for validation data for the methods
used in water solubility, solubility in organic solvents and octanol/water
partition coefficient studies were identified. Methods of analysis are
available for the determination of the active substance in the technical
material and in the representative formulation and for the determination of the
respective impurities in the technical material.
https://pubmed.ncbi.nlm.nih.gov/33913105/
These
results confirm the cytotoxic and genotoxic effects of clopyralid on non-target
organism.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8422259/
Flumioxazin
has developmental toxicity in rats, causing embryonic lethality, teratogenicity
(mainly ventricular septal defects, VSD, and wavy ribs), and growth
retardation. The mechanism of this developmental toxicity in rats has already
been shown to be embryonic anemia resulting from PPO inhibition and following
the elimination of heme biosynthesis. Even though all mammals have PPO for heme
biosynthesis, which is essential for vital activity, a remarkable species
difference in the toxicity caused by flumioxazin-induced PPO inhibition has
been reported.
https://www.sciencedirect.com/science/article/abs/pii/S0045653521029490
Flumioxazin
is a preemergence, N-phenylpththalimide herbicide that can be applied to
control a broad spectrum of weeds in a variety of cropping systems. Limited
information exists concerning the environmental fate of flumioxazin
https://efsa.onlinelibrary.wiley.com/doi/full/10.2903/j.efsa.2020.6246
The
assessment of the endocrine-disrupting properties of flumioxazin for humans and
non-target organisms could not be finalised due to the incomplete data sets.
Regarding
non-target organisms other than wild mammals, the available evidence is not
considered sufficient to conclude either on EATS-mediated endocrine activity or
on EATS-mediated adversity.
https://bee.oregonstate.edu/sites/agscid7/files/eoarc/attachments/589.pdf
more
information is needed on its effects on desirable species.
https://besjournals.onlinelibrary.wiley.com/doi/full/10.1002/2688-8319.12049
imazapic
control decreased sharply with time
mitigation
of the effects to native seeds will depend on herbicide specifics such as mode
of action and soil mobility.
Reinvasion
of areas treated with imazapic occurred quickly
the
characteristics of indaziflam that lead to longer downy brome control than
imazapic, also make it difficult to reduce injury to species seeded
concurrently with herbicide efforts. In contrast, imazapic injury to seeded
species can be limited, but downy brome control is short, resulting in eventual
reinvasion.
Our
results suggest that indaziflam applications strongly limit restoration of a
native species
https://pubmed.ncbi.nlm.nih.gov/12711414/
The
exposure to metsulfuron methyl possibly induced a leakage of nutrients from the
macrophyte leaves, which promoted an increased algal growth.
thus
this study shows that aquatic ecosystems, in particular those which are
macrophyte-dominated, may be affected by metsulfuron methyl at concentrations
that may well occur in water bodies adjacent to agricultural land.
https://academic.oup.com/femsle/article/161/1/29/585814
An
unintended consequence of the application of the herbicides could be the
influence on the microbial ecological balance of the soil, leading to a
significant change of the quality of the population. This could end up
affecting the productivity of crops negatively.
https://setac.onlinelibrary.wiley.com/doi/abs/10.1002/etc.5620191020
All
species exhibited marked effects on the vegetative growth and reproductive
performance when sprayed at 10% label rate. Less pronounced but significant
effects were shown at 1% label rate. Seed weight was reduced for B. cernua and
S. arvensis. The seedling stage was the most sensitive period for all species
tested, although surviving plants sprayed at later stages showed considerable
effects on the reproductive parts. All species tested would be at risk from
small doses of metsulfuron methyl drifting away from the sprayed areas. This
study highlights the shortcomings of the current testing schemes required prior
to pesticide registration.
https://pubmed.ncbi.nlm.nih.gov/34687687/
Knowledge
about the negative effects and mechanism of sulfentrazone (SUL) on aquatic
early life stages is still limited.
The
results inferred the environmental concentration of SUL might cause potential
cardiac and endocrine health risk in zebrafish later life stages, also
facilitated a better understanding of the sub-lethal effects and molecular
mechanism of SUL on aquatic organism.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6903747/
Bees
and the pollination services they deliver are beneficial to both food crop
production, and for reproduction of many wild plant species. Bee decline has
stimulated widespread interest in assessing hazards and risks to bees from the
environment in which they live. While there is increasing knowledge on how the
use of broad-spectrum insecticides in agricultural systems may impact bees,
little is known about effects of other pesticides (or plant protection
products; PPPs) such as herbicides and fungicides, which are used more widely
than insecticides at a global scale.
We
suggest a number of areas for further research to improve the knowledge base on
potential effects. This will allow better assessment of risks to bees from
herbicides and fungicides, which is important to inform future management
decisions around the sustainable use of PPPs.
As
herbicides and fungicides are not designed to target insects, little is known
as to whether they pose a risk to bees and other insect pollinators. However,
emerging evidence has suggested that herbicides can affect factors such as bee
navigation, learning and larval development whereas fungicides can affect food
consumption, metabolism and the immune response. Bees may be exposed to these compounds
directly via contact exposure during or after application, or via oral exposure
through contaminated nectar and pollen. In order to minimise impacts on
non-target pollinating insects such as bees, it is important to understand any
potential effects these compounds may have, to determine the risks they pose
and to mitigate against them.
With
a growing global population and increasing environmental concerns, it is
crucial to sustainably manage our agricultural systems. It is important to
understand both the benefits and risks of PPP use to humans and the environment
in order to make decisions around agricultural management. Pesticide use has
been linked with pollinator declines globally. Understanding what has been
studied in terms of different pesticide classes and substance groups and
potential impacts on bees and other insect pollinators is vital to determine
the role of PPPs in bee decline.
Although
herbicides and fungicides are not designed to target insects, the current
declines in both diversity and abundance of some bee species and attempts to
resolve the factors driving these declines warrant the scrutiny on the
potential effects of non-insecticide PPPs on pollinators.
For
herbicides, we found that most studies examined the impacts of active
ingredients rather than formulations, whereas for fungicides this was much more
compound specific. Using active ingredients allows the investigation of the
impacts of that compound alone. However, commercially, most PPPs are supplied
as formulations and so this may be a more likely exposure route to bees in the
environment. Formulations contain a variety of substances other than the active
ingredients (e.g. adjuvants), and it could be that some of these other
substances may also interact with bees. A number of different PPPs can be
applied to any piece of land in close temporal proximity, and so there is a
vast number of possible PPP combinations applied to land across the globe with
differing persistence’s in pollen, nectar and soil, and boundless possible
interactions between them. Realistically, the number of possible PPP
combinations bees could be exposed to is too large for any one study. However,
it’s important that the role of single compounds versus mixtures of compounds
(alone and in formulation) in terms of effects on bees and other pollinators
continues to be investigated in future studies.
With
an increasing interest in the sustainable use of PPPs, and public scrutiny over
the non-target effects of herbicides and fungicides in a range of areas
including human health, water contamination and pest resistance, it is likely
that there will be more interest in the impacts of herbicides and fungicides on
bees in the future with new research emerging over time. Neonicotinoids were
first released in the 1990s and their use has increased exponentially in the
last 20+ years. However, during this time, pollinators were exposed to a
variety of these insecticides. After decades of scientific research into the
negative effects of neonicotinoids on pollinators, the outdoor use of three
commercially used neonicotinoids were banned in 2018 in the European Union.
Therefore, it is important to avoid the prolonged and unsustainable use of PPPs
if further pollinator declines are to be prevented. In order to ensure safe
pesticide use, it is important to determine the effects of commercially used
PPPs on multiple bee species using methodology that accurately reflects all
possible exposure routes. Although there is an increasing amount of scientific
literature regarding herbicide and fungicide effects on bees, several key
knowledge gaps in our current understanding remain. These include a lack of
studies on bumblebee and solitary bee species, the low number of studies
considering contact and internal exposures and the lack of attention to certain
compounds over others. To fully understand the potential risks of herbicides
and fungicides to bees and to mitigate against them more research is required,
specifically diversifying the type of research (i.e. exposure route, study
species and type of exposure) and the range of compounds investigated. It is
important to address these gaps in the future if we are to build a body of
research capable of contributing towards future policy and ensure the
sustainable management of agricultural systems and continued provision of
pollination services to both crops and wild plants.
https://www.nature.com/articles/s41597-022-01584-z
Wild
and managed pollinators are essential to food production and the function of
natural ecosystems; however, their populations are threatened by multiple
stressors including pesticide use. Because pollinator species can travel
hundreds to thousands of meters to forage, recent research has stressed the
importance of evaluating pollinator decline at the landscape scale. However,
scientists’ and conservationists’ ability to do this has been limited by a lack
of accessible data on pesticide use at relevant spatial scales and in
toxicological units meaningful to pollinators.
https://www.vims.edu/research/topics/dead_zones/
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