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Malathion's Real Name is
Dimethoxy Phosphino Thioyl Thio Butanedioic
Acid Diethyl Ester |
Malathion Molecule
C10 H19 O6 P S2 |
by Dr. Wayne
Sinclair, M.D.
Allergy, Asthma & Immunology (Immunology Board Certified), Vero Beach, Florida
Richard W. Pressinger, M.Ed., Tampa, Florida
The Medical Research below was located from the University of Florida
and University of South Florida Medical Libraries.
Considerable information has been promoted by the agricultural interests
regarding the safety of malathion. There is, however, another disturbing side to this
chemical. Whereas, the original safety of malathion was based solely on its ability not
to cause immediate death in lab animals, scientists now realize there are many other ways
malathion can harm health, many of which can be quite subtle and not detected
immediately.. Malathion effects can include weakening of the immune system, neurological
damage, reproductive disorders, harm to the unborn child during pregnancy, harm to second
generation offspring and mutations/genetic damage to DNA. In essence, the chemical
is causing accelerated aging to various biological systems within the individual.
Harm to many aspects of wildlife is also extensive from malathion. Documentation to all of
these effects can be viewed in the research articles below. .
Malathion Index
Health Effects Research Summaries Included in this Report
- click topic below for more information or
scroll through the web site
Human Deaths from Malathion - 5 die and 2,800 poisoned after
malathion spraying in Pakistan
Intestinal Disorders - found higher in children born after
California aerial malathion spraying
Intestinal Disorders in Test Animals - more evidence supporting
intestinal defects in children
Leukemia - Child leukemias develop after homes sprayed with malathion and other
pesticides
Kidney Damage - physician finds kidney damage after patient sprays malathion in home
Human Birth Defect - suspected from exposure to malathion lice
shampoo
Brain Damage - for unknown reasons malathion causes far more damage
in older brains
Chromosome Defects - found in human blood cells exposed to
malathion
Gene Loss - malathion is able to literally "knock-off"
genes from our DNA molecule
Review of Malathion Genetic Studies - technically oriented -
recommended for health professionals
Health Disorders found in Second Generation Offspring - evidence for long term effects
Lung Damage - unusual effect from malathion ingredient - not found in
other pesticides
Birth Defects - occurs in hens after malathion feeding
Impurities in Malathion - highly toxic compounds increase during
storage due to time and heat
Immune System Weakening - thereby increasing risk of bacteria or
viral infections (2 studies)
Sunlight Makes Toxic - malathion reacts with ultraviolet light to
become more toxic
Impurities Weaken Detoxification - impurities found to weaken
ability of liver to detoxify
Breakdown of Malathion - time periods for malathion breakdown in soil
- forming of malaoxon
Fish Heart Defects - heart defects appear in fish exposed to
malathion
Fish Gill Damage - low levels of malathion cause deterioration of Blue
Fish gills
Frog/Tadpole Mutations - effects of malathion on causing mutations in
frogs
Shrimp Effects - malathion at low levels affects a shrimp's ability
to locate food
Lizard Organ Damage - small lizards suffer internal organ damage
from very low level malathion
Unknown Risks of Malathion - Surprising information about what we
do not know
and Bob Crawford says there is no evidence of harmful effects of malathion.........
Health Effects Research Summaries
Malathion Not as Safe as Believed - 5
Die - 2,800 Poisoned
SOURCE: Archives in Toxicology, 42:95-106, 1979
The following information is from the report from the Bureau of Tropical Diseases, Center
for Disease Control, Atlanta, Georgia entitled "The Toxicological Properties of
Impurities in Malathion." Below is a direct quote from the introductory abstract
to the article:
"During a malaria eradication program in Pakistan in 1976, out of 7,500 spray men,
2,800 became poisoned and 5 died. The major determinant of the poisoning has been
identified as isomalathion present as an impurity in the malathion. It seems almost
certain that the isomalathion was produced during storage of the formulated malathion.
The quantitative correlation found between isomalathion content and toxicity of many field
samples of malathion has been confirmed by an examination of mixtures of pure compounds.
Addition of known amounts of isomalathion to technical malathion indicates that other
active substances are present. These impurities have been identified (trimethyl
phosphorothioates) and have been shown to behave like isomalathion in potentiating the
toxicity of malathion. Some preliminary work on their toxicological properties is
reported."
Drs. W.N. Aldridge, J.W. Miles, D.L. Mount and R.D. Verschoyle
Toxicology Unit, Medical Research Council Laboratories
Pesticides Branch, Vector Biology and Control Division
Center for Disease Control, Atlanta GA
BACK TO INDEX
- Intestinal Disorders in Children Born After
California Spraying
SOURCE: Epidemiology, 3(1):32-39, January, 1992
This is the first study to show evidence of harm to human health after aerial sprayings of
malathion over human populations. Investigators surveyed 933 pregnancies identified
through hospitals in the San Francisco Bay Area, in relation to exposure to the pesticide
malathion, applied aerially to control the Mediterranean fruit fly. The good news is that
after adjustment for confounding factors, there was no association found between malathion
exposure and spontaneous abortion, intrauterine growth retardation, stillbirth, or most
categories of congenital abnormalities.
However, it was found that children who had been exposed to malathion
during the second trimester of pregnancy were showing over two and one-half times more
gastrointestinal disorders (affecting the stomach and small intestines) in comparison to
children not exposed to malathion during pregnancy.
Chem-Tox Comments: This one study certainly raises enough of a red flag
to immediately suspend all aerial applications of malathion and supports the animal
research showing genetic defects and abnormal growth of cells after exposure to malathion.
Unfortunately, this study did not investigate for increases in subtle neurological
disorders such as language delays, attention deficits, learning disabilities,
hyperactivity or conduct disorders, which the research has shown occurs with other
chemicals at exposure levels far under that which causes physical health effects.
To look at our website which summarizes how modern chemicals at very low doses can cause
subtle child behavior and learning disorders please visit http://www.chem-tox.com/pregnancy
Department of Preventive Medicine
University of Southern California, Los Angeles
BACK TO INDEX
Intestinal Problems in Test
Animals Exposed to Malathion
SOURCE: Bulletin of Environmental Contamination Toxicology,
33:289-294, 1984
In support of the above findings of intestinal disorders observed in children born several
months following the aerial spraying of malathion in California, this study also found
malfunctions of the gastrointestinal system in test animals exposed to sub-lethal levels
of malathion. Previous work by the same researchers at the Postgraduate Institute of
Medical Education and Research, India, had found a single dose of malathion "severely
impairs the digestive absorptive functions of intestine" (Chowdhury, 1980). In
this present study, the investigators looked at how subchronic malathion exposure would
affect digestion in rat intestine. After 45 days of exposure, the animals were killed and
tests conducted on the intestines. Results showed a "significant decrease in
sodium and potassium ATPase activity which suggests the disruption of ion transport
processes in intestine after pesticide exposure." There were also significant
increases in glucose and other enzymes. In conclusion the researchers stated,
"It may be surmised that subchronic malathion treatment may produce aerations in
microvillus membrane composition leading to observed changes in intestinal functions....
The results presented in this communication indicate that exposure to this pesticide may
produce alterations in intestinal functions; however, the mechanism of pesticide
interaction with intestinal epithelium remains to be elucidated."
Drs. R.K. Wali, R. Singh, P.K. Dudeja, A.K. Sarkar and A. Mahmood
Department of Biochemistry
Postgraduate Institute of Medical Education & Research, India
Gastroenterology Division
Michael Reese Hospital and Medical Center, Chicago, Illinois
BACK TO INDEX
Child Leukemia & Aplastic
Anemia after Malathion Exposure
SOURCE: The Lancet, pg.300, August 8, 1981
Seven children with bone marrow disorders have been observed over the past 8 years by
physicians at Travis Air Force Base Medical Center in California. The physicians believe
the blood disorders, in all cases, were caused by organophosphate pesticides.. All blood
disorders occurred shortly after exposure to the pesticides DDVP/propoxur and malathion.
The duration of inhaling insecticides ranged from 2 minutes in a patient enveloped in a
thick insecticide fog in a small shed to 2 days in other patients whose homes were
fumigated by their parents. Six patients had aplastic anemia and one had acute
lymphoblastic leukemia. The physicians also cited research showing leukemia in farmers has
significantly increased during the period of 1964 to 1976 (Mayo Clinic Proc, 53:714-18,
1978). Apple growers exposed to organophosphates had a higher incidence of leukopenia
(very low white blood count) than a control population (Canadian Medical Association
Journal, 92:597-602, 1965).
Drs. Jerry D. Reeves, David A. Driggers, Vincent A Kiley
Department of Pediatrics, David Grant Medical Center
Travis Air Force Base, California
BACK TO INDEX
Kidney Failure After Man Sprays
Malathion in Home
SOURCE: Journal of the American Association,
Vol.250, No.18, Nov. 11, 1983
Whereas kidney kidney damage has been observed in wildlife exposed to low levels of
malathion (listed in other research on this page), the following is documentation of
suspected kidney damage in a human patient reorted by physicians at the St Luke's Hospital
Kidney Center in Bethlehem, PA.. The following includes the some technical observations
for the benefit of our health practitioners.
A 65 year old man was admitted to the hospital because of swelling of his legs. Four weeks
before admission, he began spraying intensively with malathion and noted intermittent
inhalation and skin exposure. Thee weeks before admission, he noted an increase in weight
and, subsequently, peripheral edema. He had a five-year history of diabetes mellitus
treated with insulin. He intermittently took cimetidine for dyspepsia. He denied use of
nonsteroidal anti-inflammatory agents. The doctors summarized by stating:
"This patient experienced acute renal insufficiency with
massive proteinuria that rapidly resolved without any specific treatment. The presence of
membranous glomerulopathy and a marginally reduced C3 level suggests antigenic exposure
with subsequent immune complex deposition in the kidney. He had no known exposure to drugs
or toxins associated with the pephrotic syndrome and renal insufficiency. Cimetidine
toxicity was successfully ruled out by rechallenge with this agent. There was no evidence
of systemic collagen-vascular disease, and the biopsy specimen was not consistent with
poststreptococcal glomerulonephritis or diabetes mellitus.
The development of overt renal insufficiency with massive proteinuria within three weeks
of exposure to malathion suggests a causal relationship. although our patient has no
symptoms attributable to organophosphate poisoning, he may have had a latent exposure
without clinical manifestations, although cholinesterase activity may be inhibited.
Organophosphate exposure might cause immune complex formation by one of two mechanisms.
Antibodies might react with the organophosphate directly or to native antigens that have
been unmasked by a direct toxic effect of t he organophosphate. We postulate that
malathion provoked an immune complex nephropathy in this patient resulting in renal
insufficiency and massive proteinuria, and we stress that this toxic agent must be handled
accordingly."
Ronald K. Albright, MD; Barry W. Kram, DO; Robert P. White, MD;
St. Luke's Hospital Kidney Center, Bethlehem, PA
BACK TO INDEX
Human Birth Defect Suspected from
Malathion
SOURCE: TERATOLOGY, 36:7-9 (1987)
Malathion has been shown to cause birth defects in a variety of wildlife and at
levels lower than some other pesticides (see research below). An article printed in the
journal TERATOLOGY, (Vol.36) has researchers suspecting malathion may have caused the
birth defect known as "Amyoplasia," which is a disorder characterized by almost
total absence of skeletal muscle. The birth defect occurred in an infant girl who died
soon after birth. The main researcher, Dr. D. Lindhout, was concerned because the mother
used a malathion head lice shampoo on several occasions during the 11th and 12th week of
pregnancy. Dr. Lindhout also stated that malathion was a suspect in this type of birth
defect because -
"When administered to adult animals, malathion and related thiophosphonates
stimulate, and subsequently inhibit, the nicotinic sites in skeletal muscle, resulting in
muscle weakness and paralysis. Neonates (newborn babies) are far more sensitive to these
agents than adults, mainly because of a slower rate of detoxification of the metabolite
(the metabolite in this case would be the liver breakdown product of malathion which has
been shown to be far more toxic than malathion itself.)"
The doctors felt malathion was also suspect because there was no genetic history of this
problem in the mother's or father's family and there was no evidence of drug use by the
mother, except for the use of malathion head-lice shampoo during the early pregnancy.
Department of Clinical Genetics, Erasmus University, Rotterdam
Department of Child Neurology, University Hospital, Utrecht
BACK TO INDEX
- Brain Injury from Malaoxon at Lower Doses in
Older Animals
SOURCE: TOXICOLOGY, 79:157-167, 1993
The chemical malaoxon, formed from malathion, was found to cause neuronal (brain
cell) injury in older adult male rats at doses of only one-fifth that required to cause
similar injury in young adult rats. In this experiment, older rats (18 months) were given
a single dose of malaoxon at levels of 8.7 mg/kg. Within 10 minutes there were signs of
salivation, fasciculations and tremors. Convulsions were observed within 15 minutes in 69%
of the rats. The malaoxon also caused an increase of over twice the normal levels of
calcium in the frontal cortex of the animals' brains. Researchers believe this fact alone
could be directly toxic to brain cells. Significant reductions in the brain neurochemical
innositol was also observed in rat's experiencing covulsions. Areas affected included the
frontal cortex, hippocampus, thalamus and cerebellum.
To achieve the same intensity of symptoms and brain injury in young adult rats, it
required malaoxon exposure at levels of 39.2 mg/kg which is nearly 5 times more than the 8
mg/kg dose causing brain injury in the older rats. In conclusion the scientists stated:
"In parafin sections, the insult in the old rats characterized
by the appearance of shrunken eosinophilic neurons often surrounded by edematous vacuoles.
Vulnerable areas included hippocampal pyramidal cells, cerebral cortex and caudoputamen,
while e.g. cerebellum and brain stem were spared."
Chem-Tox Comments: Studies such as this should generate serious questions as
governmental safety exposure guidelines are based upon using young healthy test animals.
We may therefore, be subjecting our elderly population to heightened neurological risk not
observed in younger populations.
National Public Health Institute, Division of Environ. Health, Finland
BACK TO INDEX
- Chromosome Damage Occurs to Human Blood Cells
SOURCE: Mutation Research, 301:13-17, 1993
Malathion was found to cause DNA abnormalities at all doses tested in human blood cells.
Blood samples were drawn from three healthy non-smoking men, aged 23, 24 and 25. Four
different concentrations of malathion (0.02, 0.2, 2 and 20 ug/ml) were added to the blood
samples. Slides were then made of the blood samples and examined. Although all doses
showed an increase in chromosome abnormalities, a significant increase was noted for doses
of 2 ug/ml and 20 ug/ml. In conclusion, the researchers stated:
"The results show that malathion causes a dose-dependent increase in chromosomal
aberrations as well as Sister Chromatid Exchanges in human leukocyte cultures....A dose
dependent decrease in mitotic index was observed at all concentrations. Hence, our results
suggest that malathion is a mild mutagen and at higher concentrations it might cause
genotoxicity in humans."
Drs. M. Balaji, K. Sasikala
Division of Human Genetics, Department of Zoology
Bharathiar University, India
BACK TO INDEX
- Human Genes "Knocked-Off" DNA Molecule
by Malathion
SOURCE: CANCER RESEARCH, 56, 2393-2399, May 15, 1996
This 1996 study found that in experiments of human white blood cells (white blood cells
are the back-bone of our immune system) that malathion was causing "deletions"
in one section of the chromosome. In conclusion the scientists stated,
"This work provides the first evidence of an association between malathion
exposure and specific mutations in human T lymphocytes."
A quick biology lesson - Genes are not just involved in passing
hereditary traits. You have genes active in you at this moment that control what is
happening inside every cell in your body every second of the day. There are 200 genes
believed to control liver function and 200 genes believed to control immune system
function. Your lymphocytes are a type of immune system cell which are extremely important
in removing viruses and cancer cells from the body. The human aging process is simply a
result of us losing about one-half to 1% of our genes yearly (dogs lose over 4% which
explains why they age more rapidly). When we lose too many genes in the cells
controlling one part of our health, we become sick - since the cells can't operate at high
enough efficiency to do their job. It's a matter of balance - once our cells become so
inefficient because of gene loss - then we too can die - the cycle of life. The lesson to
be learned from this is we do not want to expose ourselves to chemicals (such as
malathion) that can accelerate gene loss in important cells which are protecting us from
bacteria, viruses, etc.
Genetics Laboratory, University of Vermont, Burlington, Vermont
BACK TO INDEX
- Health Problems Appear from Malathion in Second
Generation
SOURCE: Nature, November 4, 1961
Pregnant test animals exposed to malathion in this study did not show any physical health
effects. When their offspring were born there were also no obvious health effects
observed. However, when these offspring matured and had their own babies
- the researchers found this newest litter had significantly lower body weight, grew
slower and had approximately twice the number of infections..
ChemTox Comments: This research provides strong evidence for the
potential for health problems to appear long after the malathion spraying has stopped..
Department of Pharmacology, University of Toronto
BACK TO INDEX
- Lung Damage Occurs from Single Oral Dose of
Malathion
SOURCE: TOXICOLOGY, 26:73-79, 1983
An unusual effect has been observed from exposure to malathion that has not been
observed with other pesticides. A single oral dose of the chemical
trimethyl-phosphorothioate (a toxic contaminant present in all malathion), at levels of 20
milligrams per kilogram body weight, was found to cause a reduction in lung cells in the
bronchiolar epithelium of rat lungs. While the number of lung cells in a given area of
lung tissue in normal rats was over 50, there were only approximately 20 cells found in
the same area of lung tissue for rats exposed to the one dose of the malathion impurity.
No lung damage was seen when purified malathion was administered. In conclusion, the
researchers stated:
"Trimethyl-phosphorothioate and other impurities of malathion are formed as side
products during the manufacturing process (of malathion). Most organophosphorus
insecticides are high boiling liquids which cannot be readily purified by inexpensive,
conventional methods. Therefore, it is not possible to eliminate impurities completely
without prohibitive increase in costs. In short, organophosphate insecticides such as
malathion will continue to contain impurities such as trimethyl-phosphorothioate. Further,
impurities may be formed during storage at high temperature or by photochemical reaction.
Because of potential human hazards arising from exposure to these compounds, their
toxicology and mode of action should be completely understood."
Division of Toxicology & Physiology, University of California, Riverside
BACK TO INDEX
- Feeding of Malathion to Hens Causes Birth Defects
SOURCE: Agricultural Research Laboratory, Utah State University
Three hundred twelve white hens and 65 adult white males were divided into groups and fed
a diet of a laying mash to which malathion and the pesticide carbaryl were added singly
and in combination at levels of 0, 75, 150, 300 and 600 ppm for 3 weeks. Quoting the
scientists regarding the observed effects,
"Eggs were collected daily and incubated to determine hatchability and
teratogenic effects (birth defects). As the levels of pesticide in the diet increased, the
hatchability decreased significantly. The percentage of deformities increased
significantly as the concentration of pesticide in the diet increased. Marked deformities
were observed in the chicks that developed. Other findings were the liver and kidney
stored more malathion than other tissues."
BACK TO INDEX
- MALATHION BECOMES MORE POISONOUS WHEN STORED
OVER 3 MONTHS OR EXPOSED TO WARMER TEMPERATURES
SOURCE: Journal of Agricultural Food Chemistry, 25(4):946-953, 1977
The technical grade malathion (the type we are exposed to) contains approximately 11
impurities. It is these impurities which scientists state are the main poisoning
ingredients in malathion. One impurity has been shown to be approximately 500 times more
toxic than purified malathion (based on the amount needed to kill test animals - LD-50 is
20 mg/kg compared to 10,000 mg/kg for purified malathion). It is called - O,S,S-trimethyl phosphorodithioate (OSS-TMP
for short). Researchers state this, and other malathion impurities, actually
increase in amounts during simple storage (especially 3-6 months after manufacture),
making malathion far more toxic than when it was first manufactured. OSS-TMP
and other impurities have also been shown to increase even more rapidly when exposed to
temperatures around 100 degrees. How high do the temperatures become for the drums sitting
in direct sunlight or at the Tampa Airport in the non-air conditioned rooms?
Effect of Impurities on the Mammalian Toxicity of Technical Malathion and
Acephate.
BACK TO INDEX
- Immune System Weakens after Malathion Exposure
SOURCE: The Journal of Immunology,
140(2):564-570 Technical grade malathion
contains chemical impurities which have been found to weaken immune system function,
including a weakening of a type of white blood cell called "cytotoxic
lymphocytes" (which attack cancer cells and virus infected cells). The picture at
right shows six of these white cytotoxic lymphocytes (let's call them CTL's for short)
successfully attacking a cancer cell (National Geographic). These lymphocytes can also
attack viruses in the body. Malathion has now been shown to significantly weaken the CTL's
ability to perform their job effectively.
Chem-Tox Comments: Obviously, the consequences of not having these
lymphocytes remove viruses or cancer efficiently could result from either mild to serious
health disorders.
University of Virginia
Inhibition of Cytotoxic T Lymphocyte and Natural
Killer Cell Mediated Lysis by OSS-Trimethyl Phosphorodithioate is at an Early
Postrecognition Step.
BACK TO INDEX
- Report Links Pesticides with Immune System
Problems
SOURCE: SCIENCE NEWS, March 9, 1996
According to a report by the Washington, D.C. based group, World Resources Institute (WRI),
many pesticides appear to be increasing the incidence of infections, pneumonia, ear
infections, and tuberculosis. The three pesticides listed as causing this problem were
DDT, malathion, and the pesticide aldicarb. A summary of the report, appearing in the
March 9, 1996 issue of Science News, outlined many of the studies linking pesticides with
weakening of the immune system. One of the groups commissioned researchers, Dr. Lyudmila
Kovtyukh, of the Academy of Sciences in Kishinev, Moldova (a republic between Romania and
Ukraine), found that children living in areas where pesticides had been most heavily
applied experienced elevated rates of acute respiratory diseases (including pneumonia), as
well as many other signs of immune system weakness. If you would like to read the entire
March 9, 1996, SCIENCE NEWS article, it has been placed on the internet by SCIENCE NEWS
and can be seen by clicking Science News
Immune System Toxicology.
BACK TO INDEX
- MALATHION UNDERGOES DANGEROUS REACTION IN SUNLIGHT
Malathion undergoes a chemical reaction in sunlight called
"photolysis" which results in increasing the formation of the highly toxic
trimethyl impurities. -
Journal of Agricultural Food & Chemistry, 27(6):1423
BACK TO INDEX
- IMPURITIES IN MALATHION FOUND TO DISABLE
THE BODY'S NATURAL ABILITY TO DETOXIFY MALATHION
SOURCE: Toxicology and Applied Pharmacology, 49,
107-112 (1979)
Once malathion enters the body, it needs to be removed so harm is minimized. This is
the job performed in part by enzymes in the liver of all organisms. However, this research
showed that the malathion impurities - to quote the scientists - "diminish the
activities of the enzymes involved in the malathion detoxification." In other
words, the impurities damage the body's natural way of detoxifying the poison with the end
result being the chemical stays in the body for longer periods of time when exposure is to
the technical grade malathion and especially if subjected to heat and long duration
storage.
Division of Toxicology and Physiology, University of California, Riverside
BACK TO INDEX
- MALATHION BREAKS DOWN INTO TOXIC MALAOXON
SOURCE: Bulletin of Environmental Contamination
Toxicology, 57:705-712, 1996
In trying to calm the fears of Tampa residents, representatives for the Florida
Department of Agriculture have made public statements that after application, malathion
"breaks-down" in a matter of hours. What they don't tell you is that
malathion can actually break-down into compounds which are more poisonous than the
malathion itself. This is, in fact, the conclusion of research from a graduate project by
researcher N. E. Barlas at the Department of Biology, Hacetepe University, Turkey. Barlas
went on to say, "The disappearance of pesticide residues at a given location does
not mean the end of the problem. Pesticides can be translocated, bioconcentrated or
converted into more dangerous chemicals." The breakdown fate of malathion was
studied by adding malathion to soil samples containing 6 species of soil bacteria known to
breakdown the pesticide. After 10 days the samples were analyzed. Malathion content had
reduced from 100 down to 25 micrograms, so therefore, the Florida Department of
Agriculture spokes people are correct when they say it "breaks down" relatively
quickly (although in this case not in a matter of hours). However, even more important,
Barlas found that new chemicals were formed in this breakdown process including 14
micrograms of monocarboxylic acid and about 8 micrograms of the highly toxic malaoxon.
Barlas then exposed mice to the technical grade malathion and another group to the
breakdown products just mentioned. Results showed even the mice exposed to the break-down
products of malathion showed significant decreases in spleen weights and significant
changes in liver blood tests which were suggestive of liver damage. Barlas summarized by
stating, "It may be concluded that commercial malathion and it's degradation
products together have detrimental effects on mice over a period of 15 weeks of
treatment."
Department of Biology, Faculty of Science, Hacettepe University, Turkey
BACK TO INDEX
- Heart Defects in Fish from Low Levels of
Malathion
SOURCE: TERATOLOGY, 19:51-62, 1979
Levels of malathion in water as low as 5 parts per million were shown to cause heart
defects in some types of fish. The fish were studied at Rutgers University in New Jersey.
Researchers stated that malathion, if exposed to newly fertilized eggs, caused circulatory
defects including - irregular heartbeat, blood clots, oscillating blood in the
heart, pericardial edema and physical defects in the heart formation itself.
The researchers were concerned not only about the malathion but by the toxic metabolic
breakdown products a fish makes once malathion enters the fishes circulation (this happens
in humans as well).. To quote the main researcher, Dr. Solomon,
"Another possible problem arising from the use of insecticides is the effect of
their different metabolites. A primary metabolite of carbaryl is 1-napthol, while
parathion and malathion become paroxon and malaoxon. The
latter two metabolites have been shown to decrease cell numbers, DNA synthesis and protein
synthesis in cell cultures of chick pectoral muscle (Wilson '73). Thus, the
metabolite may be more detrimental than the parent compound."
Another large concern of Dr. Solomon was the finding that combining other pesticides with
malathion greatly increased the fish heart defect rate. For example, at 10 ppm of
malathion there was a 38% heart defect rate in fish. The pesticide carbaryl caused a 12%
heart defect rate at 1.1 ppm. However, when these two pesticides were combined at
these same levels - there was a 50% heart defect rate in the fish. Chem-Tox Comments: Between the malathion air assault and
additional citrus grove and residential lawn pesticide runoff - this study provides an
excellent biological explanation, for at least part of the reason, why we are observing
decreases in some fish populations (fisherman take note).
Rutgers University, Newark, New Jersey
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- Gill Damage
from Malathion Occurs to Popular Sport Fish
SOURCE: Bulletin of Environmental
Contamination Toxicology 43:123-130, 1989
This study shows one of the most graphic and startling
consequences of low level malathion exposure occurring to Florida Game Fish. Scientists
placed bluefish in test tanks that had received small doses of malathion equal to the
amounts that have been found to occur in the environment after routine spraying. After 24
hours "mild degenerative changes" were seen in the gills of the fish. After 48
hours, researchers stated "damage was more pronounced" and after 96 hours there
was severe damage resulting in a condition known as "bulbing." We feel this
study is of such importance that we are making the photographs of the malathion damaged
gills available by clicking the link damaged fish gill photographs.
Department of Biological Sciences, Kent State University, Kent, Ohio
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- Turtles Highly Vulnerable to Birth Defects from
Malathion
SOURCE: Anatomical Record, 175:390, 1973
For some reason, turtles develop birth defects from malathion easier than many other
forms of wildlife. Of concern to the turtle population in our area, malathion was shown to
cause 5 times more birth defects, such as skeletal malformations, than the pesticide
captan. Therefore, specifically regarding birth defects in turtles - malathion is far more
toxic than some other pesticides. Many turtles throughout rivers in eastern and
western Florida are showing tumors over their surface. Scientists believe these are
in fact caused by environmental pollutants (such as pesticides) which are running off via
storm water run-off into our river systems. If you would like to view a photograph
of a Florida turtle covered in tumors please click the link cancer-turtle-photograph.
Department of Anatomy, State University of New York
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- Frogs in Tadpole Stage Develop Mutations from
Malathion
SOURCE: Bulletin of Environmental Contamination Toxicology, 31,
170-176, 1983
Frogs play a very important role in the food chain, consuming vast amounts of insects.
However, like turtles, frogs have been shown to be very susceptible to developing
mutations from the pesticide malathion. Levels as low as 1 to 5 parts per million were
causing malformed tails and heads and unusual swimming patterns in tadpoles. To view
photographs of the mutations seen in frogs please click frog mutation
photographs.
Department of Zoology, University of Poona, India
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- Shrimp Lose Ability to Locate Food - Serious Risk
to Food Chain
SOURCE: Bulletin of Environmental Contamination
Toxicology, 53:127-133, 1994
If you're a shrimp - finding food is not a hit or miss coincidence. Mother nature
gives you a sort of radar called "chemo-reception" that allows you to pinpoint
where food is located in the murky waters of Tampa Bay. With your chemo-reception radar in
working order you move in and grab a bite. However, research from the Department of
Biology at the Chinese University of Hong Kong finds a surprising effect from the
pesticide malathion. At levels far below that of causing death, the chemical shows it can
drastically impair this radar food finding system. For example, in tests of shrimp exposed
and not exposed to the low levels of malathion, it was found that the shrimp in the clean
malathion-free water were 50% more successful in finding food. Considering that shrimp are
one of the more important food sources for many aquatic wildlife - the impact upon the
entire food chain is immense. This study certainly gives ammunition for local fisherman to
become involved..
Department of Biology, Chinese University of Hong Kong
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- Lizards Develop Liver & Kidney Damage at Very
Low Levels
SOURCE: Bulletin of Environmental Contamination
Toxicology, 55:730-737, 1995
Perhaps the most sensitive of all forms of wildlife to exposure to malathion are the
"dwarf lizards." These reptiles perform a service consuming significant amounts
of other small insects. Lizards were exposed to malathion at levels of only 1 milligram of
malathion per kilogram body weight (mg/kg) - 2 mg/kg - and 3 mg/kg. Each dosage caused
significant damage to the animal's livers, kidneys, and small intestines. Note, these
exposure levels are extremely small as the amount needed to cause death in most mammals is
well above 500 mg/kg. The researchers concluded by stating "Uncontrolled use of
malathion or related compounds will certainly endanger not only the lives of lizards but
also affect food chain and ecological balance of nature negatively."
Department of Biology, Faculty of Science, Osmangazi University, Turkey
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- HALF -TRUTHS HIDE IMPORTANT INFORMATION
There are two types of malathion that can be used in medical health
effects research. One is the "purified form"
(which is approximately 99.9% malathion) and the other is called "technical grade" (which is approximately 96.5%
malathion) and is the type being sprayed over Tampa and Lakeland. The technical grade is
approximately 10 times more potent in causing death to laboratory animals. The type of
malathion being sprayed over Tampa is not always the type being referred to in health
studies by malathion proponents. Compounding the problem, the malathion we are being
sprayed with has been "baking" in the hot summer which research finds converts
it into an even more toxic compound.
Division of Toxicology, University of California
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- Unkown Risks of Malathion
Perhaps what is more disturbing about malathion (and other chemicals as
well) is not what is actually known about the health effects from the chemical, but
rather, what is not known. It is important for the public to understand that although
chemical companies spend millions of dollars and several years testing their chemicals,
the testing protocols they use are dangerously incomplete.
Let's correct several common misunderstandings. First, the EPA does not test malathion.
EPA only sets up the guidelines for the testing. The chemical companies then conduct their
own tests and submit the results to EPA for review (foxes guarding the hen house?).
In fact, there have been occurrences in the past, such as with Industrial Bio-Test Labs,
in which falsified and fraudulent data was submitted to EPA. (Remember, there is extreme
financial gain to be made from registration of a chemical).
The primary tests EPA required for malathion include:
* LD-50 (the amount needed to kill 50% of the test animals)
* Tests for major organ damage
* Tests for delayed neurotoxicity in a hen after a single dose
* Skin hypersensitivity tests
* Physical birth defects
* Cancer Risk
These tests, however, are seriously inadequate. For example, EPA has been
stating for years that they would require more detailed tests for effects upon the immune
and nervous system. However, to date, these requirements have not been implemented. Below
are examples of effects that could very well be occurring from malathion and other
pesticides - but which there is just no information. In other words, this provides an
excellent example of chemical Russian Roulette with the American people.
? Learning Disabilities in math, reading, etc.
? Attention Deficit Disorder (A.D.D.)
? Hyperactivity
? Mild mental retardation?
? Lower IQ
? Language or speech delays (found highly vulnerable to low level chemical
exposure)
? Short term memory damage
? Tests of all personality facets including -
? Aggression
? Irritability
? Depression
? Increased emotionality
? Decreased head circumference in offspring (suggesting reduced brain cell
growth)
? Damage to the blood brain barrier (which functions to block toxic chemicals
from entering the brain and has been found weaker in psychiatric and Alzheimer's patients)
? Increase infertiliy or miscarriage
? Alter hormones involved in defining sexuality (as occurs with pesticide
chlordane)
? Lower sperm count (linked to increases in genetic flaws in sperm DNA)
? Slower sperm movement
? Autoimmunity - renegade immune cells which attack the body by mistake causing
rheumatoid arthritis and over 40 other diseases.
? Lower the number of immune system cells - thereby increasing risk of infection
? Slow the movement of immune system cells - thereby increasing risk of infection
? Weaken ability of immune system cells to locate bacteria, viruses, etc. - thereby
increasing risk of infection
? Weaken the ability of immune system cells to produce interferon, interleukins and other
natural compounds essential to stimulate the body's infection fighting capability - thereby
increasing risk of infection
? Weaken the ability of immune system cells (such as natual killer cells)
to locate cancer cells and efficiently remove them
? Increase risk of asthma - as has been found to occur with other pesticides
? Increase risk of allergies
? Reduce the efficiency of our DNA repair process - thereby accelerating aging
? Complete all of these tests on second generation offspring to look for true long term
subtle genetic effects
Each of the above "unknown effects" are listed here for a
reason. The reason being that all of the above effects have been found to
occur after exposure to other pesticides and chemicals when tested by various university
research programs. Of great concern, the amount of chemical exposure required to cause the
above effects is many times lower than the amount required to cause cancer, birth
defects, organ damage or other major effects. (This may be one of several reasons the
tests are not added to the protocols of chemical testing requirements). If you would
like to review our website that addresses the potential for extremely low levels of
chemicals to damage the developing unborn child - please visit Behavioral
Toxicology
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