Fructose

DDT was supposed to be the magic bullet vs. the scourge of insect-borne diseases like malaria.
Discovered in 1873, DDT (short for the less catchy dichloro-diphenyl-trichloroethane) wasn't used
widely until 1939, when Swiss chemist Paul Hermann Muller noted its effectiveness as a pesticide
during World War II, a discovery that earned him a Nobel Prize in 1948. After the war, use exploded:
from 1942 to 1972, some 1.35 billion lb. of DDT were used in the U.S.
But absent from the DDT mania was consideration of the environmental effects of dumping
millions of pounds of potent pesticides each year. Rachel Carson's seminal 1962 environmental
tract Silent Spring was the first to call attention to the nasty little fact that DDT produced fertility
and neurological problems in humans and accumulated up the food chain in wildlife, poisoning
birds. Use of the compound plummeted, and in 1972, DDT was banned in the U.S. entirely.
Effects on human health
Potential mechanisms of DDT on humans are genotoxicity and endocrine disruption. DDT may
have direct genotoxicity, but may also induce enzymes that produce other genotoxic intermediates
and DNA adducts. It is an endocrine disruptor; The DDT metabolite DDE acts as an antiandrogen
(but not as an estrogen). o,p'-DDT, a minor component in commercial DDT has weak estrogenic
activity.
Acute toxicity
DDT is classified as "moderately toxic" by the United States National Toxicology Program (NTP) and
"moderately hazardous" by WHO, based on the rat oral of 113 mg/kg. DDT has on rare occasions
been administered orally as a treatment for barbiturate poisoning.
carcinogen", and the EPA classifies DDT, DDE, and DDD as a class B2 "probable" human carcinogens.
The International Agency for Research on Cancer classifies it is as a "possible" human carcinogen.
These evaluations are based mainly on the results of animal studies.
There is epidemiological evidence (i.e. studies in humans) that DDT causes cancer of the liver,
pancreas and breast. There is mixed evidence that it contributes to leukmia, lymphoma and
testicular cancer.
Breast cancer
The question of whether DDT or DDE are risk factors of breast cancer has been the subject of
numerous investigations. While individual studies have come to conflicting conclusions, the most
recent reviews of all the evidence conclude that exposure to DDT before puberty increases the risk
of breast cancer later in life. Until recently, almost all studies measured DDT or DDE blood levels at
the time of breast cancer diagnosis or after. This study design has been criticized, since the levels
of DDT or DDE at diagnosis do not necessarily correspond to the levels present in a woman's body
at the time when her cancer first started. Such studies have thus yielded conflicting results and
taken as a whole "do not support the hypothesis that exposure to DDT is an important risk factor
for breast cancer." The studies of this design have been extensively reviewed.
2. Leaded Gasoline
Chronic toxicity
Diabetes
Organochlorine compounds, generally, and DDT and DDE, specifically, have been linked to diabetes.
A number of studies from the US, Canada, and Sweden have found that the prevalence of the
disease in a population increases with serum DDT or DDE levels.
Developmental and reproductive toxicity
DDT and DDE, like other organochlorines, have been shown to have xenoestrogenic activity,
meaning they are chemically similar enough to estrogens to trigger hormonal responses in animals.
This endocrine disrupting activity has been observed toxicological studies involving mice and rats,
and available epidemiological evidence indicates that these effects may be occurring in humans
as a result of DDT exposure. There is therefore concern that DDT may cause developmental and
reproductive toxicity.
Other
Occupational exposure to DDT (either as a farmer or a malaria control worker) has been linked to:
• Neurological problems
• Asthma
Carcinogenicity
DDT is suspected to cause cancer. The NTP classifies it as "reasonably anticipated to be a human
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