Either that was not DDT or this story is full of holes.Just before beginning each lecture he takes a teaspoonful of DDT just to show how harmless it is to humans.
http://www.pan-uk.org/pestnews/Actives/ddt.htmAcute toxicityDDT is moderately to slightly toxic to mammals. The acute oral LD50 ranges from 113-118 mg/kg in rats; 150-300 mg/kg in mice; 300 mg/kg in rabbits; 500-750 mg/kg in dogs; and >1,000 mg/kg in sheep and goats. DDT is less toxic to test animals exposed via the skin. The acute dermal LD50 for female rats is 2,510 mg/kg(10). DDT is categorised by the World Health Organisation as Class II "moderately hazardous"(11).
It mainly affects the central and peripheral nervous systems, and the liver. Acute effects in humans exposed to low to moderate levels may include nausea, diarrhoea, increased liver enzyme activity, irritation of the eyes, nose and/or throat. At higher doses, tremors and convulsions are possible(12). Deaths from exposure to DDT are rare. Even in developing countries there have been few reported cases, especially when compared with organophosphate insecticides (see PN34 pp20-21). In 1994, one fatal poisoning was reported in the US involving a child who ingested one ounce (28g) of a 5% DDT and kerosene solution(13).
Chronic effectsDDT has caused chronic effects on the nervous system, liver, kidneys, and immune systems in experimental animals. Dose levels at which effects were observed are at very much higher levels than those which may be typically encountered in humans(14). However they may be at, or even below, levels found in body fat (see below).
Reproductive effectsDDT causes adverse reproductive effects in test animals. In one rat study, oral doses of 7.5 mg/kg/day for 36 weeks resulted in sterility. In rabbits, doses of 1 mg/kg/day administered on gestation days 4-7 resulted in decreased foetal weights. In mice, doses of 1.67 mg/kg/day resulted in decreased embryo implantation and irregularities in the oestrus cycle over 28 weeks(15). Many of these observations may be the result of disruptions to the endocrine (hormonal) system.
Available epidemiological studies involving exposure to DDT have not confirmed adverse effects in humans. One study did report a significant association between maternal DDT blood levels and miscarriage, but the presence of other organochlorines in maternal blood, make it difficult to attribute the effect solely to DDT(16).
Teratogenic effects (birth defects)
Again there is evidence that DDT causes teratogenic effects in test animals. In mice, maternal doses of 26 mg/kg/day DDT from gestation through to lactation resulted in impaired learning in maze tests(17). Epidemiological studies involving humans are unavailable(18).
CancerThe evidence relating to DDT and carcinogenicity provides uncertain conclusions. It has increased tumour production, mainly in the liver and lungs, in test animals such as rats, mice and hamsters in some studies, but not in others. In rats, liver tumours were induced in three studies at doses of 12.5 mg/kg/day over periods of 78 weeks to life, and thyroid tumours were induced at doses of 85 mg/kg/day over 78 weeks. Tests have shown laboratory mice were more sensitive to DDT. Life time doses of 0.4 mg/kg/day resulted in lung tumours in the second generation and leukaemia in the third generation, and liver tumours were induced at oral doses of 0.26 mg/kg/day in two separate studies over several generations(19).
The US Department of Health and Human Services (DHHS) has determined that 'DDT may reasonably be anticipated to be a human carcinogen'. DHHS has not classified DDE and DDD, but the US Environmental Protection Agency (EPA) has determined that they are probable human carcinogens(20).
Work carried out by the US National Cancer Institute correlates breast cancer in women with increased levels of DDE in blood serum. From 14,290 women monitored in the New York University Women's Health Study, researchers selected 58 women who had developed breast cancer and 171 matched controls without cancer. After adjusting for participants' childbearing and breast feeding histories, and for family history of breast cancer, researchers found a four-fold increase in relative risk of breast cancer for women with elevated levels of DDE in the blood(21).
http://www.ourstolenfuture.org/newsc...man/humepi.htm
Here is one that say that DDT is safe but look at who published it.
http://www.atsdr.cdc.gov/tfacts35.html
DDT affects the nervous system. People who accidentally swallowed large amounts of DDT became excitable and had tremors and seizures. These effects went away after the exposure stopped. No effects were seen in people who took small daily doses of DDT by capsule for 18 months.
A study in humans showed that women who had high amounts of a form of DDE in their breast milk were unable to breast feed their babies for as long as women who had little DDE in the breast milk. Another study in humans showed that women who had high amounts of DDE in breast milk had an increased chance of having premature babies.
In animals, short-term exposure to large amounts of DDT in food affected the nervous system, while long-term exposure to smaller amounts affected the liver. Also in animals, short-term oral exposure to small amounts of DDT or its breakdown products may also have harmful effects on reproduction.
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Originally Posted by n2ize
