Persistent Organic Pollutants ... a short look at the relevance of POPs such as this article's example, DDT, as it affects ourglobal environment today even though it has been banned in many countries since the 1970's. Why is this and other POPs still in the news today? Here is some information about its lingering affects.
What was DDT used for
- DDT was introduced in WWII to control Typhus.
- A basic use of DDT was as an agricultural pesticide where it was the most widely accepted
- It was also used as a defoliant in war
- Another major use was for the control of malaria in the South Pacific, Caribbean and Africa
The History of DDT
(Dichlorodiphenyltrichloroethane - a synthetic pesticide)
- Was banned in 1970's in the US
- Produced in the US until the mid1980's
- Not banned in the UK until the 1980s
Reasons DDT was banned
- Environmental - DDT does not break down but bioaccumulates
- Direct cause of Diabetes
- Possible cause of hypothyroidism, miscarriage, reproductive toxicity, Parkinsons Disease and asthma
- Carcinogenic - Animal studies indicate it is a possible, and probable, a cause of human cancer. Examples: leukemia, lymphoma, testicular cancer, myeloma, prostate, endometrium, rectum bladder and stomach cancers.
- Human studies indicate it causes breast, liver and pancreatic cancers
Is DDT used today
- India is the only known country producing DDT
- India, North Korea and perhaps other countries continue to use DDT (legally and illegally)
- DDT is approved for use as malaria control in some countries. There are criticisms on the restrictions of DDT due to loss of human life from malaria
“DDT and its breakdown products are transported from warmer regions of the world to the Arctic
by the phenomenon of global distillation”
Other Persistent Organic Pollutants
The following chemicals have been used in place of DDT.
- "Organophosphate and carbamate insecticides,e.g. Malathion and bendiocarb are applied at roughly the same dosage
- Pyrethroids are applied more sparingly.” Believe this excerpt refers to malaria control
More Persistent Organic Pollutants
The following are similar to DDT and do not break down (bioaccumulate). They are called POPs (Persistent Organic Pollutants) :
11.Polychlorinated dibenzofurans, and
How this affects you & your family
- Because DDT, and other POPs do not break down, residues have been found in meat, eggs and dairy products in North America and Europe. Interestingly, dietary intake of DDT is higher in developing countries
- The global environmental impact of POPs is perhaps just beginning to reveal itself e.g more African wildlife species in Africa on the Endangered List
- The impact of these chemicals will be far reaching into our grandchildren's and future generations.
- POPs are highly toxic to fish and birds
- Although this topic may not specifically appear related to my blog subject, it ties in with organic gardening (food spraying and water contamination, etc); food production (overseas imported fresh produce from countries still using DDT), the DDT and breast cancer connection and generally to our global environment.
- An interesting comment made to me recently is: Did we replace one toxic chemical (DDT) for a dozen more chemicals (including carbaryl, a carbamate)? With the passage of time these may be found to more harmful to ourselves and our environment and used in much greater quantities? A really thought provoking question!
Links & References
- DDT Information from PAN
- An explanation of the DDT and Breast Cancer connection by Dr. Barbara Cohn of the Public Health Institute in Berkeley, California
- A DDT replacement Carbamate includes the chemical Carbaryl - information from the United States Environment Protection Agency.
- It was a gas leakage from a carbaryl chemical factory in Bhopal, India which killed and injured thousands of people. Years after the leakage well water in the vicinity was still contaminated. Union Carbide owned the plant at the time of the disaster.
- Carbaryl Reassessed on its carcinogenic potential (Sevin is a product of carbaryl)
- Levels of “The new DDT is known as polybrominated diphenyl ether (PBDE)” have been found in polar bears in the Arctic.
- Ban on the PBDE chemicals
- The World Health Organization's (WHO) current position using DDT in the vector control of malaria
- The Toxic Sandbox, Libby McDonald 2007 – Perigee Books