The Occurrence, Fate, and
Impact of DDT
Albert Baramuli
March 31st, 2006
History
 4,4'-(2,2,2-trichloroethane -1,1-
diyl)bis(chlorobenzene) or dichloro-diphenyl-
trichloroethane
 DDT was first synthesized in 1873 by Othmar
Ziedler.
 In 1939, Paul Hermann Müllerr, a Swiss chemist
discovered the insecticidal properties of DDT.
 DDT was developed as the first of the modern
insecticides early in World War II. (~ 1945)
 Between 1955 - 1969, World Health Assembly
adopted a Global Malaria Eradication Campaign.
History
 By 1967, Malaria was eradicated in most
developed countries and many subtropical
Asian and Latin American countries.
 In 1962, American biologist Rachel Carson
published the book Silent Spring.
 Sweden banned DDT in 1970, the USA in
1972, and the UK in 1986.
 In 2001, Stockholm Convention proposed a
global ban on DDT and 11 other organic
pollutants, effective starting May 2004.
Facts about DDT
 Technical Grade DDT contains
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

(65-80%) p,p’-DDT, (15-21%)
o,p’-DDT, (~4%) p,p’-DDD
In environment, DDT breaks
down to p,p’-DDE
Half life of DDT : ~ 2 days in air,
2 – 15 yrs in soil
Degradation by sunlight in air,
by microorganism in soil.
DDT, and especially DDE, build
up in plants and in fatty tissues
of fish, birds, and other animals
(i.e. bioaccumulation)
Health Effects
 Toxic Effects
- Animal : carcinogenic
- Human: relatively safe
 Neurobehaviour
- Poisoning : headache, tremor, fatigue, etc.
- Occupational Exposure : Reduced verbal attn.,
visuomotor speed, and sequencing
 Cancer
- Breast, Pancreatic, Liver, Prostate, Testicular,
Endometrial.
- Lymphoma, Myeloma
Health Effects
 Reproductive Health
- Semen volume & quality, testosterone amount,
sperm DNA damage
- Reduce probability of pregnancy
- Spontaneous abortion
- Birth defects
- Shorter lactation period
 Infant and Child Growth
- Height
- Mental and psychomotor development
 DNA Damage
- Raised IgA and reduced IgG
- Necrosis
Source of Exposure
How might I be exposed to DDT ?
 Eating contaminated foods, such as root and leafy
vegetable, fatty meat, fish, and poultry.
 Eating contaminated imported foods from countries
that still allow the use of DDT to control pests.
 Breathing contaminated air or drinking contaminated
water near waste sites and landfills that may contain
higher levels of these chemicals.
 Infants fed on breast milk from mothers who have
been exposed.
 Breathing or swallowing soil particles near waste
sites or landfills that contain these chemicals.
Malaria in Africa
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Efficiency of DDT vector
control depends on:
Coverage of spraying
Mosquito Species
Resistance to DDT
Climate (rainfall,
temperature, latitude)
Fight Against Malaria
In 1998, the WHO, World Bank,
UNDP and UNICEF conceived
and partnered to create the Roll
Back Malaria movement
Red – insecticide treated bed
nest
Blue – insecticide residual
spraying
Green – both
White - undetermined
Conclusion
 High exposure to DDT will affects the nervous
system, shorter lactation period in women.
 Further test will still need to be conducted, to
determine the benefits versus the health risks
of using DDT
 Well coordinated efforts in combination with
efficient health infrastructure should have
better success in malaria control
References
1. Beard J. DDT and Human Health. Science
2.
3.
4.
5.
of the Total Environment 2005; 355:78-89
Rogan WJ, Chen A. Health Risks and
Benefits of DDT. Lancet 2005; 366:763-73
http://en.wikipedia.org/wiki/DDT
http://www.epa.gov/history/topics/ddt/01.htm
http://www.atsdr.cdc.gov/toxprofiles/phs35.ht
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