Pesticides applications need a much attention as it can affect negatively Environment and living organisms include human being; due to less biodegradable it reaches all aspects of environment. Chlordane are known as persistent organic pollutants (POP), classified among the "dirty dozen" and banned by the 2001 STOCKHOLM convention.

1. TOPIC: CHLORDANE IN THE ENVIRONMENT
PREPARED BY MUTAMBYI
VALERIEN MSc. Environmental
chemistry, University of
Rwanda
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vmutambyi@gmail.com

2. OUTLINE
 INTRODUCTION
 PESTICIDE IN THE ENVIRONMENT
 PESTICIDE BEHAVIOUR IN THE ENVIRONMENT(INCLUDE CHLORDANE)
 SYNTHESIS OF CHLORDANE
 CHLORDANE METABOLISM
 CHLORDANE ROUTES OF METABOLISM
 PROPOSED METABOLIC PATHWAYS FOR CHLORDANE IN ANIMALS
EVEN IN THE ENVIRONMENT
 CHLORDANE REMEDIATION
 ENVIRONMENTAL IMPACT
 CHLORDANE MOVEMENT IN WATER AND SOIL
 CONCLUSION
 REFERENCES
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3. INTRODUCTION
 Chlordane is very resistant to chemical and biological degradation. It is highly
immobile and migrates very poorly.
 Disappearance of chlordane from soils is mainly due to volatilization.
 In spite of its very low mobility in soil, chlordane may be a low-level source of
contamination in groundwater when applied by subsurface injection.
 Enter water as run off from urban and agriculture
 Chlordane are known as persistent organic pollutants (POP), classified among
the "dirty dozen" and banned by the 2001 STOCKHOLM convention.
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4. PESTICIDE IN THE
ENVIRONMENT
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5. PESTICIDE BEHAVIOUR IN THE
ENVIRONMENT(INCLUDE CHLORDANE)
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6. SYNTHESIS OF CHLORDANE
Cis
Trans
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7. CHLORDANE METABOLISM
 Chlordane is metabolized very slowly
 Most metabolites of chlordane are far less toxic than the parent material,
However, oxychlordane is more toxic with a LD50 in rats of 19mg/Kg.
 Livers of rat and humans had almost identical ability to degrade chlordane,
except that human liver has little capacity to convert trans-nonachlor to trans-chlordane.
Due to that trans-nonachlor accumulate in people not in rats.
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8. CHLORDANE ROUTES OF METABOLISM
 Hydroxylation
 Dehydrochlorination
 Dehalogenation
 Hydrolytic removal
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9. PROPOSED
METABOLIC
PATHWAYS
FOR
CHLORDANE
IN ANIMALS
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10. CHLORDANE REMEDIATION
 Chlordane was applied under the home/building during treatment
for termites and the half-life can be up to 30 years.
 Chlordane has a low vapor pressure and volatilizes slowly into
the air of home/building above.
 To remove chlordane from indoor air requires either ventilation
(Heat Exchange Ventilation) or activated carbon filtration.
 Remediation in soil by mixing chlordane with aqueous lime and
persulfate.
 By phytoremediation
 Mycoremediation e.g: Phanerochaete chrysosporium has been
found to reduce concentrations of chlordane by 21% in water
within 30 days and in solids within 60 days.
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11. ENVIRONMENTAL IMPACT
 Chlordane is hydrophobic, due to that it adheres to soil
particles and enters groundwater only slowly.
 It requires many years to degrade.
 Chlordane bioaccumulates in animals
 It is highly toxic to fish, e.g: LD50 of 0.022–
0.095 mg/kg (oral).
 Main bioaccumulating constuents are: Oxychlordane
(C10H4Cl8O), heptachlor epoxide, cis-nonachlor
and trans-nonachlor.
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12. CHLORDANE MOVEMENT IN WATER AND SOIL
 chlordane dissipated from surface water by volatilization,
sorption to bottom and suspended sediments and particulates and
uptake by aquatic organisms. Additionally, volatilization is
affected by: temperature, wind and water turbulence.
 In soil, chlordane adsorbs to the organic matter and volatilize
slowly overtime. "doesn't leach significantly”
 Volatilization is the major loss for chlordane, the rate depends on:
Soil organic content, water content, temperature, relative humidity,
vapor pressure and adsorption to soil.
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13. CONCLUSION
Therefore, volatilization kinetics may be faster than adsorption
kinetics. Sandy soil and soil with small amounts of organic matter
retain chlordane less than soil with clay and/or organic content.
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14. REFERENCES
[1] World Health Organization, “Chlordane in Drinking-water”, 2004
https://www.who.int/water_sanitation_health/dwq/chemicals/chlordane.pdf
[2]U.S Department of health and human services, agency for toxic substances and disease
registry "Toxicological Profile for Chlordane”, 2018
https://www.atsdr.cdc.gov/toxprofiles/tp31.pdf
[3] U.S. Environmental Protection Agency ,“Toxicological review of chlordane”, 1997
https://cfpub.epa.gov/ncea/iris/iris_documents/documents/toxreviews/0142tr.pdf
[4] Agency for Toxic Substances and Disease Registry “Chlordane”, 1995
https://www.atsdr.cdc.gov/toxfaqs/tfacts31.pdf
[5]National pesticide information center, “Chlordane”, 2001
http://www.npic.orst.edu/factsheets/chlordanegen.pdf
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