DINAMIKA RACUN LINGKUNGAN DI DALAM

EKOSISTEM

Oleh

Sudrajat

Dosen FMIPA, Fak.Kedokteran, Fak,Kesmas, Pasca Sarjana Ilmu Lingkungan dan

Staf Peneliti PPLH Universitas Mulawarman

Samarinda2005

Xenobiotik :

Merupakan bahan asing bagi tubuh makhluk hidup, antara lain adalah racun.

Di alam banyak sekali racun, termasuk polutan-polutan kimia dari pabrik, kendaraan dan lainnya.

Zat kimia / xenobiotik akan mengalami transportasi ke berbagai kompartemen lingkungan atau transformasi apabila terdapat zat yang dapat bereaksi dengannya membentuk senyawa lain.

PRINSIP-PRINSIP DASAR DI DALAM PEMAJANAN RACUN

- ABSORPSI , - DISTRIBUSI, - METABOLISME &- ELIMINASI

TOXICOKINETICS - TOXICODYNAMIC

PEMAJANAN RACUN-RACUN YANG UMUM DI SEKITAR KITA

UVradiation

PM

mercuryindoorair

pesticides& toxics

biologicals

lead

ozone

asbestos

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Kasus Bhopal• December 3-4, 1984: 40 tonnes of

methyl iso-cyanate (MIC) released from Union Carbide plant at Bhopal

• Accidental release caused by leakage of water into MIC storage tank

• None of the six safety systems worked• Safety standards and maintenance

system ignored for months• Complete absence of community

information and emergency procedures

• Public alarm system operated after the gas had leaked for nearly four hours

Industrial disaster“Industrial disasters are caused by chemical, chemical, mechanical, civil, electrical, or other process failures due to accident, negligence or incompetence, in an industrial plant which may spill over to the areas outside the plant causing damage to life and property.”

“Chemical disasters are occurrence of emission, fire or explosion involving one or more hazardous chemicals in the course of industrial activity or storage or transportation or due to natural events leading to serious effects inside or outside the installation likely to cause loss of life and property including adverse effects on the environment.”

Chemical disaster

Major industrial disasters that shaped public policy

• Triangle Factory Fire New York (USA) 1911100 garment workers died in fire • Minamata Mercury Disaster (Japan) 1932-68

3,000 people suffered, severe mercury poisoning symptoms, deformities or death • Seveso Dioxin Disaster (Italy) 1976

3,000 animals died, 70,000 slaughtered to prevent dioxins entering food chain • Bhopal Gas Disaster (India) 1984

15,000 killed, over 500,000 affected

Bhopal Gas Tragedy • Worst industrial disaster in history• 2,000 people died on immediate

aftermath• Another 13,000 died in next fifteen years• 10-15 persons dying every month • 520,000 diagnosed chemicals in blood

causing different health complications• 120,000 people still suffering from

– Cancer– Tuberculosis– Partial or complete blindness, – Post traumatic stress disorders,– Menstrual irregularities

• Rise in spontaneous abortion and stillbirth

Second generation effect• ICMR, IMA, AMA studies show – Children born with genetic defects– Growth retardation in boys– Hormonal chaos among girls

• Ground water contamination with high level of mercury, lead, nickel, VOCs and HCH

• High prevalence of skin and gastro-intestinal diseases

• Bioaccumulation of toxins found in vegetables and breast milk

Chisso Corporation• Chisso = nitrogen– Produced fertilizer

• 1907: Chisso Corp. builds a fertilizer plant in the Minamata.• Job openings

• 1925: plant begins dumping untreated wastewater into Minamata Bay– Kills fish– Fisherman Payoffs

http://www.japanfocus.org/images/592-3.jpg

Chisso Corporation• 1932: Chisso plant begins to

produce acetaldehyde to be used in the production of plastic, perfume and drugs.• Acetaldehyde is made from

acetylene and water with a mercury catalyst.

• After WWII plastic production boomed and Chisso Corp. grew.

• By 1970: Chisso brought Japan 60% of its income and owned nearly 70% of the land in Minamata.

http://www-personal.umich.edu/~tobin/Smith2.jpg

Bizarre Behavior in Animals

• Early 1950’s:– Dead fish wash ashore– Crows fall out of sky– Suicidal dancing cats

• Mercury moves up the food chain.

http://flickr.com/photos/tropicalrips/127535537/

Mid 1950’s: Behavior Seen in Humans

• Behaviors witnessed:– Loss of motor control in

hands– Violent tremors– Swaggered walk– Insanity

• “Cat-dancing” disease• Nobody knew the cause

of the epidemic.– Many hid for fear of

ridiculehttp://www.hamline.edu/personal/amurphy01/es110/eswebsite/ProjectsSpring03/ebarker/Minamata%20Web%20Page.htm

Putting the Pieces Together• 1956: Researchers at

Chisso Corp. Hospital experiment on cats with wastewater from the Chisso plant.• They warn Chisso corp.

• Chisso corp. redirects the flow of wastewater to avoid being caught.– A larger geographical area

contaminated. – Children born with

horrifying deformities.http://www.nimd.go.jp/archives/english/tenji/a_corner/image/hasseimap.gif

Putting the Pieces Together• 1968: Government ran

Public Health service traces the contamination to the Minamata Chisso plant.

• Government halts the production of acetaldehyde

• 1972: Government publically announces Chisso Corp’s part in the Minamata epidemic and orders Chisso Corp to pay compensation to the families that were affected.

http://www.icett.or.jp/lpca_jp.nsf/505b1fe895fd2a8c492567ca000d587d/e35dc782654b21d7492567ca000d8c50?OpenDocument

The Aftermath• 30-70 tons of methyl

mercury was dumped into the Bay

• 10,000 people affected by Minamata disease.– 3,000 died

• Compensation has been given to families as recently as 1990.– Highest compensation for

the disaster was just under $3,000.

http://www.physorg.com/news110359851.html

Centers for Disease Control and Prevention

Methylmercury :In the Body

• Methylmercury exposure in humans is from consumption of fish, marine mammals, and crustaceans

• 95% of fish-derived methylmercury is absorbed into the gastrointestinal tract and distributed throughout the body – Highest in concentration in

hair

www.mercury.utah.gov/images/health_effects.jpg

Minamata Disease in the Nervous System

Areas in red show areas typically affected by the presence of methylmercury in

the system . The lesions show characteristic signs and symptoms in

Minamata disease.1. Gait disturbance, loss of balance

(ataxia), speech disturbance (Dysarthria)

2. Sight disturbance of peripheral areas in the visual fields (constriction of visual fields)

3. Stereo anesthesia (Disturbance of sensation)

4. Muscle weakness, muscle cramp (disturbance of movement)

5. Hardness of hearing (hearing disturbance)

6. Disturbance of sense of pain, touch or temperature (Disturbance of sensation)

National institute of Minamata Disease Archives

Symptoms of the Disease

• Mild – Ataxia – Muscle weakness– Narrowed field of vision – Hearing and speech

damage • Severe cases cause– Insanity – Paralysis– Coma – Death

W. Eugene SmithTomoko Uemura in Her Bath

Minamata, 1972

More Symptoms • A significant effect of

Minamata is the onset of symptoms similar to those of cerebral palsy

• Fetal Minamata Disease– A pregnant mother ingests

toxic fish and the methylmercury concetrates inside the placenta.

– Harms the fetus while the mother is relatively unaffected

http://picasaweb.google.com/jazzyv0504/SAKURA#5065603192708172658

These are all children with congenital (fetal) Minamata Disease due to intrauterine methyl mercury poisoning (Harda 1986).

Examples of chemicals in food, air, water linked to birth defects Cross placenta to embryo

Defects of brain, nerves, heart Defects of skeleton (often limbs) Blindness, deafness Spasticity Mental retardation

Defects of heart, brain Blindness, deafness

Decreased fetal growth Defects of face (cleft palate/lip) Emotional & learning problems

Mercury: The Basics

• Mercury (Hg) is the only metal that is liquid at room temperature. It melts at -38.9oC and boils at 356.6oC.

• Mercury conducts electricity, expands uniformly with temperature and easily forms alloys with other metals (called amalgams).– For these reasons, it is used in

many products found in homes and schools.

Mercury Chemistry• Mercury exists in three

oxidation states:– Hg0 (elemental mercury). – Hg2

2+ (mercurous).– Hg2+ (mercuric).

• Mercurous and mercuric form numerous inorganic and organic chemical compounds.– Organic forms of mercury,

especially methyl mercury, CH3Hg(II)X, where “X” is a ligand (typically Cl- or OH-) are the most toxic forms.

Uses of Mercury• We use its unique properties to

conduct electricity, measure temperature and pressure, act as a biocide, preservative and disinfectant and catalyze reactions.– It is the use of mercury in

catalysis that contributed to the events in Minamata.

• Other uses include batteries, pesticides, fungicides, dyes and pigments, and the scientific apparati.

Mercury in the Environment• Upwards of 70% of the mercury in

the environment comes from anthropogenic sources, including:– Metal processing, waste

incineration, and coal-powered plants.

• Natural sources include volcanoes, natural mercury deposits, and volatilization from the ocean.

• Estimates are that human sources have nearly doubled or tripled the amount of mercury in the atmosphere.

The Aquatic Mercury Cycle

Methylmercury concentrations• Freshwater fish 0.1-0.4 ppm• Ocean fish 0.6-0.8 ppm• Predator fish > 1.0ppm• Fish in “polluted” water > 10ppm• Fish from Minamata Bay ~ 50ppm

• Whale meat ~4ppm• Whale liver >1000ppm

Reference dose 0.1g/kg bw/day

135-lb. woman: 1.5oz. Swordfish or 7 oz. tuna/week 50-lb. child: 0.5oz. Swordfish or 2.6 oz. tuna/week

Methylmercury poisoningMinamata Japan, 1930s-1950s

Four Major Pollution di Jepang Case Accused Ruling

Minamata Disease(organic mercury in sea water)

Chisso Corp. Plaintiff wins in 1973

Itai-itai Disease(cadmium in river water)

Mitsui Kinzoku Plaintiff wins in 1972

Niigata Minamata Disease (organic mercury in river water)

Showa Denko Plaintiff wins in 1971

Yokkaichi Asthma(air pollution by petrochemicals)

Mitsubishi Petrochemicals etc

Plaintiff wins in 1972

Yokkaichi 1961 Yokkaichi today

Award winning photo of Minamata

Disease victim

Congenital Minamata disease;Mercury toxicity, Japan 1955

• Microcephaly

• Cerebral palsy / spastic

• Mental deficits

• Malformation of ears,

heart, skeleton, eyes

Minamata Bay

Bhopal, India

This presentation is based on the text articles, Bhopal, pp. 347-352, and Chemical Safety in Developing Countries, the lessons of Bhopal, pp. 353-358

In Dec. 3, 1984, an explosion at the Union Carbide plant released a deadly cocktail of poison gas made up of methyl isocyanante, hydrogen cyanide, monomethyl amine, carbon monoxide and up to 20 other chemicals.

4 months later report on 1,430 deaths. By 1999, the toxic gas killed at least 16,000 according to local estimates; tens of thousands continue to suffer.

Arsenic toxicity from well waters in Bangladesh and CCA

• Bangladesh may be heading for an epidemic of arsenic poisoning with an estimated 60 million regularly ingesting arsenic through drinking contaminated groundwater

•Surveys of groundwater used for drinking and cooking have identified unacceptably high concentrations of arsenic in several thousand deep tube wells, Dr Karim said. Some wells contain 0.4 mg/l of arsenic, 40 times the acceptable concen

BMJ. 2000 March 25; 320(7238): 826. Half of Bangladesh population at risk of arsenic poisoning

Dioxin and Chloracne

• VIENNA, Austria (CNN) -- Dioxin poisoning caused the disfiguring illness afflicting Ukrainian opposition presidential candidate Viktor Yushchenko, doctors at an Austrian hospital said Saturday.

• Doctors said at a news conference that they suspect a "third party" administered the poison in September, possibly by putting it in Yushchenko's soup.

External to Internal environment

..a hint of integration?

PESTICIDE EXPOSURE ISSUES

OCCUPATIONAL

• Production

• Farmers

• Child labor

• Women in reproductive age

• Exterminators

ENVIRONMENTAL

• Domestic use• Pesticides in: food water soil• Spillage (su do ra)• Waste

II. DINAMIKA POLUTAN DI DALAM EKOSISTEM

Mekanisme kerja suatu polutan/ zat terhadap suatu organ sasaran pada umumnya melewati suatu rantai reaksi yang dapat dibedakan menjadi 3 fase utama :

a) Fase Eksposisib) Fase Toksokinetikc) Fase Toksodinamik ( Lihat gambar 2.1.).

Skema dampak pencemaran polutan terhadap makhluk hidup

( dimodifikasi dari : Holdgate, 1979)

2.1). Fase Eksposisi : Merupakan ketersediaan

biologis suatu polutan di lingkungan dan hal ini erat kaitannya dengan introduksi oleh manusia. Selama fase eksposisi, zat beracun dapat diubah melalui berbagai reaksi kimia/fisika menjadi senyawa yang lebih toksis atau lebih kurang toksis. Jalur intoksikasinya lewat Oral, Saluran Pernafasan dan Kulit.

Faktor-faktor yang mempengaruhi sifat polutan tersebut adalah atmosfer, air dan biota. Transportasi dan transformasi zat/polutan di lingkungan berhubungan erat dengan sifat-sifat fisikokimia polutan; proses transportasi polutan di lingkungan dan transformasi polutan yang terjadi di lingkungan. Pemaparan bahan polutan ke lingkungan akan mengalami berbagai proses transformasi tergantung atas media transportasinya antara lain air, udara, tanah dan biota ( Connel Des. W . and Gregory J. Miller, 1984).

Gb. Interaksi xenobiotik dengan berbagai faktor di lingkungan ( Sumber : McKinney, 1981).

2.1.2.Media Transpor

Media transpor dapat berupa :

-Udara

-Air

-Tanah

-Makanan

-Organisme

-Rantai Makanan

-Dll

2.1.3. PERILAKU POLUTAN DI LINGKUNGAN

Dipengaruhi oleh kompartemen penyusun bumi yakni :

-Udara

-Air

-Tanah

-Biota

Sifat-sifat kimiawi dan mekanisme yang mengatur bentuk penyebaran polutan di dalam kompartemen dan di antara kompartemen penyusun lingkungan tersebut merupakan hal yang penting untuk dikaji.

Aspek-aspek tersebut antara lain : LAJU PERPINDAHAN ZAT KIMIA DAN ENERGI DI DALAM ALAM DAN PROSES PENYEBERANGAN POLUTAN TSB ANTAR KOMPARTEMEN

2.1.4. PROSES PERUBAHAN BENTUK

Proses perubahan bentuk polutan di perairan meliputi

hidrolisis,

fotolisis,

degradasi secara mikroorganisme dan

oksidasi.

2.1.5. PROSES BIODEGRADASI

Biotransformasi ( perubahan bentuk biologis) dan biodegradasi polutan oleh mikroorganisme ( bakteri, jamur, protozoa dan ganggang) merupakan proses pembuangan dan perubahan yang penting dalam air, sedimen dan tanah. Reaksi mencakup oksidasi, reduksi, hidrolisis dan terkadang penataan ulang dan dipengaruhi oleh bangun molekul dan kepekatan zat polutan, sifat alamiah mikroorganisme, keadaan lingkungan dan suhu.

Dalam udara akan mengalami fotolisis, reaksi; dalam air akan mengalami hidrolisis, foto-lisis, degradasi oleh mikrobiota, oksidasi; dalam tanah akan mengalami proses fotolisis, degradasi dan pada biota akan mengalami proses metabolisme ( Lihat gambar 3 ).

Jika suatu polutan/zat kimia mengalami kontak dengan suatu organisme, maka terjadinya efek biologi atau efek toksis setelah proses absorbsi polutan tersebut ke dalam tubuh organisme.

Umumnya hanya bagian zat yang berada dalam bentuk terlarut, terdispersi secara molekul yang dapat diabsorbsi. Penyerapan ini sangat ditentukan oleh faktor kadar zat dan lamanya bersentuhan antara zat yang terdapat dalam bentuk yang dapat diabsorpsi dengan permukaan organisme yang berkemampuan mengabsorbsi zat tersebut. Pada pencemaran lingkungan, bagian dosis yang dapat diabsorbsi menentukan derajat eksposisi yang efektif terhadap organisme.

2.2. Fase Toksokinetik :

Hanya sebagian dari jumlah zat yang diabsorpsi mencapai organ target suatu zat toksis di dalam tubuh organisme , yakni di lokasi jaringan/molekul yang sesuai. Dibedakan atas proses -proses :- Absorbsi dan distribusi ( Invasi)- Biotransformasi- Akumulasi- Ekskresi

ROUTES OF ENTRY

• INGESTION (MAINLY IN ACUTE

EXPOSURES)

• INHALATION (MAINLY IN CHRONIC)

• DERMAL (MAINLY IN CHRONIC)

• PARENTERAL

Routes of administrationRoutes of administration

Drug half-life varies as a function of route of administration

Half-life = time for plasma drug conc. to fall to half of peak level

ROUTES OF

ADMINISTRATION

2.3. Fase Toksodinamik : Suatu kerja zat toksis pada umumnya adalah hasil interaksi dari sejumlah proses yang sangat rumit dan kompleks.

a) Lewat interaksi kimia antara suatu zat atau metabolitnya dengan substrat biologi akibat terbentuknya ikatan kimia kovalen yang tak bolak-balik atau terjadinya perubahan substrat biologi sebagai akibat dari suatu perubahan kimia zat.b) Lewat interaksi yang bolak-balik ( reversible) antara zat asing dengan substrat biologi. Hal ini menyebabkan suatu perubahan fungsional, yang lazimnya hilang bila zat tersebut dieliminir dari plasma.

PENYEBARAN RACUN LINGK. DI DALAM PENYEBARAN RACUN LINGK. DI DALAM TUBUH MANUSIA :TUBUH MANUSIA :

- Protein plasma mengikat senyawa asing - Protein plasma mengikat senyawa asing HATI DAN GINJALHATI DAN GINJAL

- Bertugas untuk mengeluarkan senyawa - Bertugas untuk mengeluarkan senyawa asing. Hati berkapasitas merubah senyawa asing. Hati berkapasitas merubah senyawa racun ( biotrans-formasi) menjadi tidak racun ( biotrans-formasi) menjadi tidak aktif).aktif).

- LEMAK- LEMAK Tempat penyimpanan penting bagi Tempat penyimpanan penting bagi

senyawa yang larut dalam lemak ( mis. senyawa yang larut dalam lemak ( mis. DDT, PCB, )DDT, PCB, )

- TULANG- TULANG Berfungsi sebagai penyimpan senyawa Berfungsi sebagai penyimpan senyawa

Flour, Pb, Strontium.Flour, Pb, Strontium.

MEKANISME KERJA POLUTAN THDP BAGIAN TUBUH ORGANISME

- Interaksi dengan sistem enzim : Inhibisi enzim tak bolak balik Inhibisi enzim secara reversible Pemutusan Reaksi Biokimia Sintesis Zat mematikan Pengambilan ion logam yang penting untuk kerja enzim Inhibisi penghantaran elektron dalam rantai respirasi

MEKANISME KERJA POLUTAN THDP BAGIAN TUBUH ORGANISME

- Inhibisi pada transpor oksigen karena gangguan pada hemoglobin Keracunan karbon monoksida Pembentukan Metheglobin dan Sulfahemoglobin Proses Hemolitik

- Interaksi dengan Fungsi Umum Sel Kerja Narkose Pengaruh Penghantaran Rangsang Neurohumor

- Gangguan pada sintesis DNA dan RNA Kerja Sitostatika Kerja Imunsupresiva Kerja Mutagenik Kerja Karsinogenik

- Kerja Teratogenik- Reaksi Hipersensitif ( Reaksi alergi) Reaksi fotoalergik Sensibilisasi cahaya Reaksi fototoksis

Iritasi Kimia langsung pada Jaringan Kerusakan kulit akibat zat kimia Gas yang merangsang Gas air mata Zat yang berbau- Toksisitas pada Jaaringan- Penimbunan ( Sekuestrasi) Zat asing Penimbunan dalam jaringan lemak Penimbunan dalam Tulang Pneumokoniosis

Gb Skematik Mekanisme metabolik zat racun di luar hati dan di dalam hati

Gb Skematik Mekanisme metabolik zat racun di luar hati dan di dalam hati

EFEK BIOLOGIS

MERUPAKAN RESULTANTE AKHIR DARI SEJUMLAH PROSES YANG SANGAT KOMPLEKS, YAKNI INTERAKSI ANTARA FUNGSI HOMEOSTASISNYA DENGAN XENOBIOTIK. Jika proses homeostasis gagal, karena berbagai hal misalnya dosis terlalu tinggi, paparan konsentrasi terlalu pekat dan kontinyu, keadaan gizi kurang, dstnya maka akan terjadi efek biologis yang diekspresikan bermacam-macam .

Tabel 1. Rangkuman beberapa pengaruh biokimia dan fisiologis penting dari suatu zat beracun.

No Sasaran Proses yang Terganggu

1. Membran sel a. Perubahan atau modifikasi permeabilitas memberanb. Pengacauan sistem transportasi membran sel

2. Enzim Inhibisi dapat balik atau tidak balik dari enzim (koenzim, subtrat atau pengaktif logam), oleh zat kimia

3. MetabolismeLemak

Pengacauan metabolisme lemak dapat menyebabkan kegagalan fungsi hati, termasuk akumulasi lemak patologis dalam hati dan kapasitas lemak untuk mengsintesis kolesterol dapat digagalkan.

Tabel 1. Rangkuman beberapa pengaruh biokimia dan fisiologis penting dari suatu zat beracun.

No Sasaran Proses yang Terganggu

4. Biositensis Protein

Sintesis zat protein dapat dipengaruhi oleh sejumlah besar zat eksogenus, terutama melalui penekanan kapasitas protein untuk mensintesis yang bertempat di dalam reticulkum kasar endoplasmik (r ER) di dalam sitoplasma. Dalam beberapa kasus, salah satu pengaruh dapat merangsang timbulnya pertambahan sintesis protein mikrosomal.

5. Sistem enzim Mikrosomal

Pergantian dalam fungsi enzim mikrosomal-rangsangan atau inhibisi yang diinduksi oleh banyak zat kimia di lingkungan.

6. Proses Pengaturan dan Pertumbuhan

Struktur atau kegiatan enzim pengatur dapat diubah dan sintesis, penyimpanan, pelepasan atau pengasingan hormon dapat digagalkan oleh zat beracun dalam berbagai cara, penurunan laju pertumbuhan dapat mengikuti gangguan kimiawi jalur dan laju metabolisme.