A quarterly publication of Beyond Pesticides
Vol. 30, No. 2, Summer 2010
he common diseases affecting the public’s health are all too
well-known in the 21st century: asthma, autism and learning
disabilities, birth defects and reproductive dysfunction,
diabetes, Parkinson’s and Alzheimer’s diseases, and several types
of cancer. Their connection to pesticide exposure continues to
strengthen despite efforts to restrict individual chemical exposure,
or mitigate chemical risks, using risk assessment-based policy.
The Pesticide-Induced Diseases Database, launched by Beyond
Pesticides, facilitates access to epidemiologic and laboratory
studies based on real world exposure scenarios that link public
health effects to pesticides. The scientific literature documents
elevated rates of chronic diseases among people exposed to
pesticides, with increasing numbers of studies associated with
both specific illnesses and a range of illnesses. With some of these
diseases at very high and, perhaps, epidemic proportions, there
is an urgent need for public policy at all levels –local, state, and
national—to end dependency on toxic pesticides, replacing them
with carefully defined green strategies.
Data Supports Policy Change
The database is a tool to support efforts to eliminate the
continued use of hazardous pesticides in favor of green strategies
that emphasize non-toxic and least-toxic alternative practices
and products. The studies in the database show that our current
approach to restricting pesticide use through risk assessment-based
mitigation measures is not working. This failed human experiment
must be ended. The warnings of those who have expressed
concerns about risk assessment, such as EPA Administrator under
Presidents Nixon and Reagan, William Ruckelshaus, have been
borne out by three decades of use and study. Mr. Ruckelshaus
in 1984 said, “We should remember that risk assessment data
can be like the captured spy: If you torture it long enough, it will
tell you anything you want to know.” EPA’s risk assessment fails
to look at chemical mixtures, synergistic effects, certain health
endpoints (such as endocrine disruption), disproportionate effects
to vulnerable population groups, and regular noncompliance
with product label directions. These deficiencies contribute to its
severe limitations in defining real world poisoning, as captured by
epidemiologic studies in the database.
An enlightened policy approach to proposed or continued toxic
chemical use, in an age where the adverse effects have been
widely and increasingly documented, is to first ask whether there
is a less toxic way of achieving the toxic chemical’s intended
purpose. Simply, “Is there another practice that would make the
substance unnecessary?” This approach does not preclude and
should demand the prohibition of high hazard chemical use, those
chemicals that are simply too dangerous.
The alternatives assessment approach differs most dramatically
from a risk assessment-based policy is in rejecting uses and
exposures deemed acceptable under risk assessment calculations,
but unnecessary because of the availability of safer alternatives.
For example, in agriculture, where the database shows clear links
to pesticide use and cancer, it would no longer be possible to use
hazardous pesticides, as it is with risk assessment-based policy,
when there are clearly effective organic systems with competitive
yields that, in fact, outperform chemical-intensive agriculture
in drought years. Cost comparisons must take into account
externalities such as water pollution and water utility expenses,
associated with chemical-intensive farming. The same is true
for home and garden pesticide use and defined integrated pest
management systems with prescribed practices and only specific
substances as a last resort.
Wide Range of Diseases
Linked to Pesticides
Database supports policy shift from risk
to alternatives assessment
By Kagan Owens, Jay Feldman
and John Kepner
Pesticide-Induced Diseases Database
Vol. 30, No. 2, Summer 2010
shift away from pesticide dependency. Public policy must advance
this shift, rather than continue to allow unnecessary reliance on
pesticides. Regulatory restrictions must be tied to alternatives
assessment that move chemicals off the market or prohibit their
marketing as safer approaches and technologies emerge.
About the Database
In order to track the varying public health effects of pesticide
exposure, Beyond Pesticides has established the Pesticide-Induced
Diseases Database, which tracks diseases and other health issues
linked to real world pesticide exposure, providing access to
published studies and their findings. The database is housed on
the Beyond Pesticides website at www.beyondpesticides.org/
health, as it requires periodic updating. The current database,
which contains hundreds of studies, itself is preliminary and will
be added to over the coming months. We urge readers to send
studies to email@example.com that you think should be
added to the database.
Findings and Database Entries
According to the Alzheimer’s Association, Alzheimer’s disease
(AD), the most common form of dementia,
is a progressive and fatal brain disease. As
many as 5.3 million Americans are living
with Alzheimer’s disease. Alzheimer’s
destroys brain cells, causing memory loss
and problems with thinking and behavior
severe enough to affect work, lifelong
hobbies or social life. Alzheimer’s gets
worse over time, it is fatal, and has no
research is just beginning to make the
link between pesticides and AD. A recent
study of individuals from an agricultural
community in Utah shows increased risks among pesticide-
exposed individuals for all causes of dementia (hazard ratio, HR,
1.38) and an even greater risk for AD (HR 1.42). The risk of AD
associated with organophosphate exposure is the greatest (HR
1.53) followed by organochlorines (HR 1.49).
epidemic levels, particularly in young children. In the U.S. alone,
around 16 million people suffer from asthma. Asthma is a serious
chronic disorder, and in some cases life-threatening disease, of the
lungs characterized by recurrent attacks of bronchial constriction,
which cause breathlessness, wheezing, and coughing. Researchers
have found that pesticide exposure can induce a poisoning effect
linked to asthma.
Low-income populations, people of color, and children living in
inner cities experience disproportionately high morbidity and
mortality due to asthma. According to the National Institutes
of Health’s National Institute of Allergy and Infectious Disease,
African Americans are four to six times more likely than whites to
die from asthma. Therefore, any time our policies allow regulators
to permit uses of pesticides with known asthma effects, which is
done daily, a disproportionate impact is felt in the African-American
community. Among other policies, this toxics policy contributes
Beyond Agricultural Pesticide Exposure
While agriculture has traditionally been tied to pesticide-related illnesses, of the 40 most commonly used pesticides in schools, 28
can cause cancer, 14 are linked to endocrine disruption, 26 can adversely affect reproduction, 26 are nervous system poisons and 13
can cause birth defects. Of of the 30 most commonly used lawn pesticides, 19 can cause cancer, 13 are linked to birth defects, 21 can
affect reproduction and 15 are nervous system toxicants. A number of published studies using animal toxicity data and human cells/
tissue laboratory data also show that pesticides are linked to several major public health problems.
leading cause of school absenteeism due
to chronic illness.
At publication, the database lists 41
studies linking pesticides to asthma.
Studies show that pesticides not only
trigger asthma attacks, but are also a root
cause of asthma. A landmark 2004 study
finds that not only do environmental
exposures lead to above-average asthma
rates among children, but that timing of
exposure is also crucial. Examining over
4,000 school-aged children in California,
the researchers discovered that children
exposed to herbicides during their first
year of life are four and a half times
more likely to be diagnosed with asthma
before the age of five; toddlers exposed to
insecticides are over two times more likely to get asthma.
Birth and Fetal Defects
birth defects to mothers who all worked for Ag-Mart Produce, a
company that produces chemically-treated tomatoes and other
agricultural products, brought the connection between birth
defects and pesticide exposure into the public consciousness.
Birth defects are structural or functional abnormalities present at
birth that cause physical or mental disabilities, ranging from mild
to fatal. Researchers have identified thousands of different types
of birth defects. Currently, birth defects are the leading cause of
death for infants during the first year of life.
of the medical journal Acta Paediatrica reports that the highest
rates of birth defects for U.S. babies arise when conception
occurs during the spring and summer months, when pesticide
use increases and high concentrations of pesticides are found
in surface waters. A strong association is found between higher
rates of birth defects, including spina bifida, cleft lip, clubfoot and
Down’s syndrome, among women who conceive while nitrates,
atrazine and other pesticides are at the high end of their seasonal
While agriculture has traditionally been tied to pesticide-related
illnesses, 19 of 30 commonly used lawn pesticides and 28 of 40
commonly used school pesticides are linked to cancer.
Even with the growing body of evidence linking
environmental exposures to cancer in recent years, a
report released May 6, 2010 by the President’s Cancer
Panel finds that the true burden of environmentally-
induced cancer is greatly underestimated. The Panel’s
report, Reducing Environmental Cancer Risk: What
exposure is not a new front on the war on cancer,
the grievous harm from carcinogenic chemical use
has not been addressed adequately by the nation’s
At publication, the database lists 260 studies
linking pesticides to various forms of cancer (see
specific types of cancer below). While a number of
published scientific studies using animal toxicity data
and human cells/tissue laboratory studies show that
pesticides are known or suspected to be carcinogenic,
epidemiologic studies confirm laboratory results. The
cancer and pesticides used in agriculture and
throughout the urban environment in homes,
schools, and public places.
Brain Cancer – There are two main types
of brain cancer. Primary brain cancer starts
in the brain. Metastatic brain cancer starts
somewhere else in the body and moves to the
brain. According to the American Brain Tumor
Association, brain tumors are the most common
of the solid tumors in children, and the second
most frequent malignancy of childhood.
Brain tumors are the second leading cause of
cancer-related deaths in males under 40 and
the second leading cause of cancer-related
deaths in females under age 20.
nervous system may play a role in the development of brain tumors.
A population-based, case control study of children ten years of
age or younger that analyzes functional genetic polymorphisms
and parents’ use of home insecticide treatments suggests that
exposure in childhood to insecticides in combination with a
reduced ability to detoxify them increases the risk of developing
brain tumors. Several studies show adults with brain cancer are
more likely to have been exposed to pesticides.
Breast Cancer – Doctors estimate that one in eight women
leading cause of death in North America for women 35 to 50 years
old. Genetics can only account for five to ten percent of cases.
According to the Breast Cancer Fund, a growing body of scientific
evidence suggests that exposures to toxic chemicals, including
pesticides, in the environment are contributing to high breast
At publication, the database lists 11 studies linking pesticides to
breast cancer. Some pesticides are breast carcinogens and others
act by disturbing or mimicking hormones in the body, which can
lead to breast cancer. (See Endocrine Disruption section.) A 2006
Long Island Breast Cancer Study Project report demonstrates that
self-reported lifetime use of residential pesticides is associated
with an increase in risk for breast cancer. The increase is found for
women who report the use of pesticides overall, specifically lawn
and garden pesticides, and is particularly high for households with
Leukemia – Cancer of the blood-forming cells of bone marrow,
33 percent of the incidence of all childhood cancer and causing
more deaths among children and adults
under the age of 20 than any other cancer,
yet strikes ten times as many adults
as children. Several published studies
show a “critical window of exposure” to
pesticides, whether used in the home or
from parental occupational exposure, that
are associated with leukemia in children,
showing an especially high risk correlation
with pesticide exposure during the
At publication, the database lists 40
studies linking pesticides to leukemia.
Studies link leukemia to both residential
and agricultural exposure to pesticides,
for adults, children and in utero. One case-
control study in California finds household
pesticide use can nearly quadruple the
pesticides increase the risk to over six-fold (OR 6.5).
significantly elevated risk for leukemia (OR 3.35).
Lymphoma – Cancers that originate in the lymph system are
and non-Hodgkin’s lymphoma
(NHL). Lymphomas are the
most common type of blood
cancer in the U.S. It is the 7th
most common in adults and
the 3rd most common cancer
in children. The more common
non-Hodgkin’s lymphoma is a
cancer of the immune system.
The incidence of NHL has been
increasing over the past several
decades and has doubled since
the early 1970s.
According to the Lymphoma
Foundation of America, 75 out
of all 99 epidemiologic studies
conducted on lymphoma and
pesticides find a link between
the two. The report states that
data from the National Cancer
Institute show that people
develop lymphoma often in
states and locations with the
highest pesticide use. The
report finds that farmers are at
the highest risk for lymphoma.
Dozens of studies in the database confirm the risk to farmers and
Prostate Cancer – Cancer of the prostate, a gland of the
male reproductive system, is the second most common cancer
among American men, with one in six men diagnosed during their
lifetime. It is also the second leading cause of death for American
men. Incidence and death
trends show that prostate
cancer has been slightly
decreasing since 1994.
At publication, the database
lists 23 studies linking
pesticides to prostate cancer.
Studies show elevated rates
of prostate cancer in Vietnam
veterans exposed to Agent
Orange and to farmers and
pesticide exposure. A study
published in 2003 in the
shows that individuals who
have worked in agriculture
have a 40% increased risk of
having prostate cancer over
the general population.
disruption is likely to be a
mechanism for developing this
type of cancer.
Soft Tissue Sarcoma
muscle, fat, fibrous tissue, blood
vessels, or other supporting
Epidemiology: The Challenge of Finding Patterns of Harm
Despite evidence to the contrary, chemical industry critics of epidemiologic studies linking pesticides to major diseases argue that they
are of limited value because of their reliance on records and study participants’ memory, among other issues. In fact, the correlation
of patterns of chemical use with an effect is difficult to establish in epidemiology and therefore may underestimate hazard effects.
When a correlation is established it raises serious concern. The epidemiologic studies in the Pesticide-Induced Diseases Database
show an overall pattern that links pesticide exposure to major diseases.
Inherent limitations, such as the following, only add to the power of these studies as patterns of diseases tied to pesticide exposure
emerge: (i) categorizing farmers all together as a group based on just the job title and not exposure assessments, yet farmers can
have diverse exposure patterns from one another; (ii) seasonal and migrant farmworkers are not usually aware of the pesticide(s)
which have been used where they are working; (iii) grouping chemicals by classes, when diseases may not be restricted to a certain
chemical family; (iv) small number of study subjects; (v) recall bias among study participants; and, (vi) a lack of detailed exposure
yet risk is increased with exposure to certain chemicals, radiation
therapy and certain genetic diseases.
At publication, the database lists 7 studies linking pesticides to
soft tissue sarcoma. A 1995 case-control study of Denver children
finds that yard pesticide applications are linked to a four-fold
increase in risk to soft tissue sarcomas (OR 4.0).
Other Cancers – With so many pesticides on the market
and possible combinations for exposure, there are scores of
different types of cancers with scientific links to pesticides. As the
President’s Cancer Panel points out, “Approximately 40 chemicals
classified by the International Agency for Research on Cancer
(IARC) as known, probable, or possible human carcinogens, are
used in EPA-registered pesticides now on the
At publication, the database lists 105 studies
linking pesticides to other types of cancers.
These include cancer of the bladder, bone,
cervix, colon, eye, gallbladder, kidney/renal,
larynx, lip, liver, lungs, mouth, esophagus,
ovarian, pancreas, rectum, sinus/nasal,
stomach, testicles and thyroid, as well as
melanoma (a form of skin cancer), multiple
myeloma (cancer of the plasma cells of bone
marrow) and neuroblastoma (cancer of the
Developmental and Learning
Roughly one in six children in the U.S. has one or
more developmental disabilities, ranging from
a learning disability to a serious behavioral
or emotional disorder. Scientists believe
that the amount of toxic chemicals in the
environment that cause developmental
and neurological damage are contributing
to the rise of physical and mental effects
being found in children. Studies show
children’s developing organs create “early
windows of great vulnerability” during
which exposure to pesticides can cause
great damage. In the U.S., requirements
for testing pesticides and other chemicals
for potential developmental and learning
disorders are minimal.
A developing brain is much more
susceptible to the toxic effects of chemicals
than an adult brain. During development,
the brain undergoes a highly complex series of processes at different
stages. Interference from toxic substances that disrupt these
processes can have permanent consequences. That vulnerability
extends from fetal development through infancy and childhood to
adolescence. Research has shown that environmental toxicants,
such as pesticides, at low levels of exposure can have subclinical
effects—not clinically visible, but still important adverse effects,
such as decreases in intelligence or changes in behavior.
At publication, the database list 26 studies linking pesticides to
learning and developmental disorders. These include general
developmental delays, attention deficit hyperactivity disorder
(ADHD) and autism. A 2009 study published in the journal Pediatrics
links a mother’s exposure to urban air pollutants known as
polycyclic aromatic hydrocarbons (PAHs), which include pesticides,
to a reduced intelligence quotient (IQ) in their children.
Common household products –detergents, disinfectants, plastics, and pesticides– contain chemical ingredients that enter the body,
disrupt hormones and cause adverse developmental, disease, and reproductive problems. Known as endocrine disruptors, these
chemicals, which interact with the endocrine system, wreak havoc in humans and wildlife. The endocrine system consists of a set of
glands (thyroid, gonads, adrenal and pituitary) and the hormones they produce (thyroxine, estrogen, testosterone and adrenaline),
which help guide the development, growth, reproduction, and behavior of animals, including humans. Hormones are signaling
molecules, which travel through the bloodstream and elicit responses in other parts of the body.
Endocrine disruptors function by: (i) Mimicking the action of a
naturally-produced hormone, such as estrogen or testosterone,
thereby setting off similar chemical reactions in the body; (ii)
Blocking hormone receptors in cells, thereby preventing the action
of normal hormones; or (iii) Affecting the synthesis, transport,
metabolism and excretion of hormones, thus altering the
concentrations of natural hormones. Endocrine disruptors have
been linked to attention deficit hyperactivity disorder (ADHD),
Parkinson’s and Alzheimer’s diseases, diabetes, cardiovascular
disease, obesity, early puberty, infertility and other reproductive
disorders, and childhood and adult cancers.
More than 50 pesticide active ingredients have been identified
as endocrine disruptors by the European Union and endocrine
disruptor expert Theo Colborn, PhD. Endocrine disruption is
the mechanism for several health effect endpoints. See the
related sections (Cancer, Developmental and Learning Disorders,
Parkinson’s disease, Reproductive Health) for more information.
Pesticides and You
Deficit Hyperactivity Disorder is a neurobehavioral developmental
disorder that causes inattention, impulsivity, and hyperactivity.
It is estimated that around two million children in the U.S. have
At publication, the database lists 8 studies
linking pesticides to ADHD. In one study
linking ADHD to pesticide exposure, scientists
from the University of Montreal and Harvard
University examine data from the National
(NHANES), a program of studies designed to
assess the health and nutritional status of
adults and children. The study shows that
for children with a 10-fold increase in the
concentration of dialkyl phosphate metabolites
in their urine (an indicator of organophosphate
exposure) the odds of ADHD increase by more
than 50%. For the breakdown product dimethyl
triophosphate, the odds of ADHD almost double
in kids with above-average levels compared to
those without detectable levels.
Autism – This complex developmental disorder, which is on
problems with social interaction and communication. The
symptoms range from mild to very severe, appearing before
the age of three and lasting throughout a person’s life. Research
several regions of the brain and/or abnormal levels of serotonin
or other neurotransmitters in the brain, suggesting that autism is
associated with the disruption of normal brain development early
in fetal development.
At publication, the database lists 5 studies linking pesticides
to autism. A study published in the October 2007 issue of
Environmental Health Perspectives shows that children born to
mothers living near agricultural fields, where organochlorine
pesticides, specifically endosulfan and dicofol, are applied during
their first trimester of pregnancy, are six times more likely to have
children that develop autism.
of diseases characterized by high blood glucose levels that result
from defects in the body’s ability to produce
and/or use insulin. Type 1 diabetes is usually
diagnosed in children and young adults. In type
1 diabetes, the body does not produce insulin.
Type 2 diabetes is the most common form of
diabetes and is most common in communities
of color and the aged population. In type 2
diabetes, either the body does not produce
enough insulin or the cells ignore the insulin.
Pesticides and other environmental factors are
almost always linked to type 2 diabetes.
At publication, the database lists 6 studies
linking pesticides to diabetes. Several studies
show that pesticides and other pollutants can
elevate the risk of type 2 diabetes by 20% to
more than 100%. A study by the National
Institutes of Health (NIH) finds pesticide
applicators with regular exposure to pesticides
are at greater risk for type 2 diabetes.
Applicators that had used certain
insecticides more than 100 lifetime days
nearly doubled their diabetes risk.
disease (PD) occurs when nerve cells in
the substantia nigra region of the brain
are damaged or destroyed and can no
longer produce dopamine, a nerve-
signaling molecule that helps control
muscle movement. People with PD have
a variety of symptoms including loss of
muscle control, trembling and lack of
coordination. They may also experience
depression, urinary difficulties, and sleep disturbances. Over time,
symptoms intensify. At least one million Americans have PD and
about 50,000 new cases are diagnosed each year. With less than
one percent of cases caused by genetics, researchers have been
looking for the potential risk factors for developing Parkinson’s
disease (PD). The epidemiological and toxicological evidence is
repeatedly identifying exposure to pesticides, as well as specific
gene-pesticide interactions, as significant adverse risk factors that
contribute to PD.
studies from 1983-2005 published in the journal Environmental
between PD and pesticide exposure, finding sufficient evidence
that an association exists and is strongest for exposure to herbicides
and insecticides, and after long durations of exposure.
A robust body of literature details reproductive effects in fish,
amphibians, and reptiles related to exposure to endocrine
disruptors. Evidence of these effects has also been seen in wild
mammals such as polar bears and seals. Environmental exposure
assessments and wildlife, laboratory and epidemiologic studies
show exposure to low-level environmental contaminants, such
as pesticides and other chemicals, subtly undermines the ability
to reproduce. The study of endocrine disruption is revealing
mechanisms that show how specific environmental contaminants
can alter fertility. Laboratory animal experiments have confirmed
these wildlife findings.
both males and females, antiandrogenic (demasculinizing) effects,
increased rates of miscarriage, altered sex ratios and altered
maturity. A 2006 study published in the journal Epidemiology
has found inverse associations between pesticides and male
testosterone levels. The study found that high levels of the urinary
metabolites of chlorpyrifos (TCPY) and carbaryl and naphthalene
(1N) correlate directly with low levels of testosterone in male
laboratory experiments that show strong associations or linkages
between infertility rates and exposure to pesticides support the
conclusions of this study.
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