Persistent Organic Pollutants

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Sigid Hariyadi
DIOXIN
PCBs
Pesticides
POPs
Persistent Organic Pollutants (POPs) are chemical
substances that persist in the environment, bioaccumulate
through the food web, and pose a risk of causing adverse
effects to human health and the environment.
 Bahan kimia yang tetap ada di lingkungan (tidak luruh, tidak terurai)
 Bioakumulasi dalam jejaring makanan
 Menyebabkan resiko yg merusak bagi kesehatan manusia dan lingkungan
The "dirty dozen" includes:
(6) endrin
(7) heptachlor
(1) PCBs
(8) hexachlorbenzene (9) mirex
(2) aldrin
(3) chlordane (10) polychlorinated dibenzo-p-dioxins
(11) polychlorinated dibenzofurans, and
(4) DDT
(12) toxaphene.
(5) dieldrin
POPs (Persistent Organic Pollutants)
Examples = Dioxin, PCB, DDT (Chlorinated)
Dioxin: stable; slow to degrade
Persistent Organic Pollutants - Dioxin
Generated from:
burning wood, coal, oil,
household trash, and
chlorine bleaching of pulp and paper
Accumulates in fat of animals  biomagnification
Causes:
- cancer
- weakened immune response
Persistent Organic Pollutants - PCBs
PCBs :
 non-flammable;
 not dissolved in water;
 high boiling points;
 does not conduct electricity well  used for
transformers and capacitors.
Sources of PCBs
 Due to their stability, use in industrial processes and
product (e.g. dielectric fluida in capasitor and
transformator).
Production and uses of PCBs
Compound
Trade Names
Major Uses
Polychlorinated
biphenyls (PCBs)
Aroclor;
Phemoclor;
Kanechlor; Clopen
Clophen; Fenclor;
Santotherm
Capacitor Dielectric;
Transformer collant;
Hydraulic fluid;
Heat transfer fluid.
Polychlorinated
triphenyls (PCT)
Aroclor; Kanechlor
Adhesives and
sealants
Polychlorinated
naphthalenes
(PCN)
Halowax
Capasitor dielectric,
oil additive
Polybrominated
biphenyls (PBB)
Firemaster
Fire retardant
Persistent Organic Pollutants - PCBs
More than one billion pounds of PCBs have been made
Accumulates in fat of animals  biomagnification
Causes:
- cancer
- hormonal and reproductive disruptions
- decrease cognitive abilities (dopamine)
Chemical
Structures
of PCBs
Chemical Properties of
PCBs
Chemical characteristics of PCBs are mostly
determined by positions and number of chlor
content
 High Stability especially those with more than 5 atomic
chlor content;
(hydro= air, phobia= takut)
 Hydrophobic;
(lipo ⇨ lipid= lemak, philic= suka)
 Lipophilic;
 Low solubility.
Behaviour of PCBs in an Ecosystem
 Dispersion (as a function of solubility);
 Low Degradation (higher chlor content, more difficult
to degrade);
 Mobility and absorption in sediment (higher chlor
content, lower mobility);
 Availability in sediment depend on its texture and
organic material content (High PCBs content in fine
sediment).
Biodegradation of PCBs:
Accumulation of PCBs
Readily accumulated through water and food
 PCBs is accumulated in lipid.
 Sedimentary Organisms are contaminated with a
concentration similar or more than that observed in
sediment.
Elimination of PCBs
Elimination of PCBs from organisms is related
to the chemical properties
cleanse
 Uptake rate and depuration in mussels is high for
higher chlor PCBs, but low for those having low chlor
content.
 Decreasing consentration of PCBs in female organism
occurs in a gametogenesis period in which PCBs is
transferred to her eggs (more lipophilic), or in a
spawning period.
PESTISIDA
WHAT IS A
PESTICIDE ?
 a pesticide is any agent used to kill or control any pest.
Pests can be insects, rodents or birds, unwanted plants
(weeds), fungi, or microorganisms such as bacteria and
viruses.
 herbicides
 fungicides
 microbiocides
 rodenticides
Many household products are pesticides:
• Obat nyamuk dan serangga (semprot, bakar, gel)
• racun tikus
• bahan anti jamur
• berbagai desinfektan (pembersih lantai)
http://www.pesticideinfo.org/Docs/ref_general1.html
Active ingredients are the specific chemicals contained in
a pesticide product that are designed to kill a particular pest.
By law, the active ingredient must be identified by name on
the label together with its percentage by weight.
"Inert" ingredients are commonly mixed with the active
ingredients to create a formulated pesticide product.
Formulated pesticide products are the form of the
pesticide that is available to the consumer, grower, or pest
control applicator, and may take the form of sprays, bait
stations, fly strips (pita perangkap lalat), dusts, etc.
 Inert ingredients include solvents, emulsifiers,
spreaders, and other substances mixed into pesticide
products to increase the effectiveness of the active
ingredients, make the product easier to apply, or to
allow several active ingredients to mix in one solution.
An inert ingredient is simply any ingredient in the
product that is not intended to affect a target pest .
Inert ingredients can be as much as 99% of pesticide
products.
Many inert ingredients have adverse health effects
and may themselves be used as pesticides.
The U.S. EPA list of pesticide inert ingredients:
8 of 382 inert ingr.  of toxicological concern
75 of 382 inert ingr.  potentially toxic
Chemical Structures of Pesticides:
Pesticides in Marine Environment
 Chlorophenoxy acids (e.g. 2,4 D)
 Substituted tetrahydrophthalinides
(e.g. captan)
 Organochlorine (e.g. p,p’-DDT,
lindane, dieldrine, dan mirex)
 Organophosphorus compounds
(e.g. malathion)
 Carbamate (e.g. carbanyl)
Most Common Pesticides
 DDT = (1,1,1-trichloro-2,2-di(4-chlorophenyl) -ethane),
 DDD = (1,1-dichloro-2,2-di(4-chlorophenyl)-ethane)
 DDE = (1,1-dichloro-2,2-di(4-chlorophenyl) -ethylene)
Persistent Organic Pollutants - DDT
DDT is an insecticide; stable and slow to degrade.
Paul Muller won the Nobel Prize in 1948 for developing
DDT.
Benefits = Controlled spread of malaria; Provided crop
protection
Persistent Organic Pollutants - DDT
Problems with DDT: DDT is not metabolized very rapidly by
animals; instead, it is deposited and stored in the fatty tissues
 biomagnification
Persistent Organic Pollutants - DDT


Toxic to fish
Increased mortality in birds: calcium decreased in egg shells
Accumulation of DDT
 In fish, come through predation, and also skin and gill.
 Short exposure at a concentration of < 1 µg/L is toxic for
freshwater and marine fish.
 Mature Organisms contaminated DDT can be transferred to
embryo and lead to death within a concentration range of
1,1 - 2,4 µg/kg.
DDT as Persistent compound
due to:
 Low vapour pressure
 High solubility in lipid
 Resistant to degradation and
photooxidation
Transformation of DDT
 DDE exists within aerobic or oxidation condition.
 DDD exists within anaerob or reduction conditions.
 DDE and DDD have similar stability and toxicity to DDT .
Persistent Organic Pollutants -
DDT
Estrogen mimic in Vertebrates: feminizes males - lower sperm count; alters behavior
Human Health:
 decreased mental function
 male infertility
 cancer
Persistent Organic Pollutants -
Unintentional Pathways:
DDT
Persistent Organic Pollutants DDT
Problems with DDT (and other pesticides):
 Evolution of resistance
 Non-target species and creation of new pests
Biomagnification of DDT (ppm)
Fish-eating birds (0.17 – 2.07)
Fish (0.17 – 2.07)
shrimp
Mud snail
Clam
Insects
0.16
0.26
0.42
0.23 – 0.3
Organic debris
Cladophore
Plankton
Marsh plants
0.3 – 13.0
0.03
0.04
0.33 – 2.8
Sea-water
Fresh-water
1 x 10-6
1 x 10-5
(Preston, 1989)
Pesticides Cycles
Pesticide Concentration Standard
Compound
Fresh water aquatic life
Human fish consumption
Aldrin
3.0 ug/liter (acute)
0.079 ng/liter
Chlordane
2.4 ug/liter (acute)
0.46 ng/liter
Dieldrin
2.5 ug/liter (acute)
0.076 ng/liter
DDT
1.1 ug/liter (acute)
0.024 ng/liter
DDE
1,050 ug/liter (acute)
N/A
Mirex
0.001 ug/liter (chronic)
N/A
Parathion
0.065 ug/liter (acute)
N/A
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