ANALISIS RISIKO KESEHATAN (HEALTH RISK ASSESSMENT)dr. AGUNG S. DWI LAKSANA, MSc.PHBAGIAN IKM/IKK PPD UNSOED 2007

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OUTLINE

DEFINITION (PENGERTIAN) OF HRA SCOPE (RUANG LINGKUP) OF HRA EPIDEMIOLOGY STUDY VS HRA RISK ASSESSMENT STEPS:Identifikasi Bahaya Analisis Dosis-respon Analisis Jalur Pajanan Karakterisasi Risiko2

PENGERTIAN

Risk assessment is the systematic scientificcharacterization of potential adverse health effects resulting from human exposure to hazardous agents or situation Risk is defined as the probability of an adverse outcome Hazard is used to refer to intrinsic toxic properties3

RISIKO (RISK)

Prakiraan probabilitas dampak yang merugikan kesehatan sebagai akibat pajanan zat-zat kimia dalam jumlah dan dengan jalur pajanan tertentu Risiko kualitatif: tinggi, sedang/biasa, rendah Risiko kuantitatif: 1>Risiko>0 - Risiko = 0 pasti tidak akan terjadi - Risiko = 1 pasti akan terjadi

Risiko kuantitatif dinyatakan sebagai bilangan pecahan: E-5 = 10-5 = risiko 1/100.000 1,3E-3 = 1,3 x 10-3 = risiko 1/770 1,2E-5 = 1,2 x 10-5 = risiko 1/83.0004

RUANG LINGKUP

Health risk assessment can be conducted for any hazard for which there are adequate toxicological (from animal or human exposure) or epidemiologic data and either measured or estimated exposure in an individual or population The spectrum of health effect: acute, subchronic and/or chronic5

Ruang lingkup

Acute adverse health effect: observed a few hours after high-level exposure (or dose) Subchronic: observed from repeated doses over 30-90 days in animal and for up to about 1 year in human Chronic: observed following repeated low-level exposures over many years

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STUDI EPIDEMIOLOGI vs ANALISIS RISIKOSTUDI EPIDEMIOLOGI ANALISIS RISIKO

Pajanan (inhalasi, ingesi, absorbsi) Penyakit Berbasis Lingkungan Risk Agent, Media Lingkungan & PHBS DosisRespons (NOAEL, Karakterisasi Risiko (HQ)

Manajemen Risiko (I, C, t, f, D)

Komunikasi Risiko (PHBS)

LOAEL)

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HEALTH RISK ASSESSMENT STEPSEmpat Langkah Utama:

Hazard Identification (identifikasi bahaya) Dose-Response Assessment (analisis dosisrespons atau toxicity assessment: hubungan dosis pemajanan dengan efek) Exposure Assessment (analisis jalur pajanan atau penilaian kontak) Risk Characterization (karakterisasi risiko)8

RISK ASSESSMENT STEP

EXAMPLE OF QUESTIONS ASKED BY THE RISK ASSESSORWhat substances harm humans, and what kind of harm is it? Of all the substances involved in a problem area (e.g., air pollution) which substance will we look at in this analysis? What could happen to humans if they are exposed to different levels of these compounds? What are the cancer-causing effects and non-cancer-causing effects? What are the sources and duration of exposures to this substance? How many people are exposed to the hazardous substance? What range of doses do they receive? Given all we have learned so far, what are the human health impacts of current exposures? What is the risk to an individual? What is the risk to entire population? Are any subpopulation more impacted than others? How confident are we in the overall analysis?9

Hazard identification

Dose-response assessment Exposure assessment

Risk characterization

1. HAZARD IDENTIFICATION

HI is the step in which it is determined whether exposure to an agent could (at any dose) cause an increase in the incidence of adverse health effects (e.g., cancer, birth defects, neurotoxicity) in humans Methods: 1. Structure/Activity Relationship

Important information:

Agent structure Solubility stability pH Volatility Chemical reactivity10

Identifikasi bahaya2.

3.

4.

In vitro and short term test: can be designed to provide information about mechanism of effect Animal bioassay: gold standard for prediction of human carcinogenicity risk Epidemiologic data: the most convincing line of evidence for human risk

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2. DOSE RESPONSE/TOXICITY ASSESSMENT1. 2.

3.

Define the relationship between the dose of an agent and the observance or expected occurrence of a specific toxicologic effect The fundamental basis of the quantitative relationships between exposure to an agent and the incidence of an adverse response Tetapkan Zat Kimia Indikator atas dasar

Toksisitas (cancer slope factor, RfD) Konsentrasi dalam media vs background level Konsentrasi dalam media vs baku mutu/standar Frekuensi deteksi Fate & transport characteristics Completeness of pathways

4.

Concentration-Toxicity Screening R = (CiTi)12

DUA EFEK ZAT TOKSIKNONKARSINOGENIK

KARSINOGENIK

Berambang (threshold) Ada dosis di atas nol yang tidak berefek sampai dosis tertentu tercapai Risiko dinyatakan sebagai NONCANCER HAZARD berupa Hazard Quotient & Hazard Index berdasarkan Intake dan Reference Dose

Tidak Berambang (nonthreshold) Selalu ada efek pada setiap dosis di atas nol Risiko dinyatakan sebagai CANCER RISK: 1. Slope Factor (risk per doses) 2. Unit Risk (risk per media concentrations) 3. Cancer Risk13

EVALUASI EFEK NONKANKER (EFEK SISTEMIK) - 1

Efek sistemik = semua endpoint zat toksik selain kanker dan mutasi gen Efek sistemik dievaluasi menggunakan RfD (reference dose) sebagai ukuran RfD (US-EPA) Acceptable Daily Intake (WHO): jumlah zat kimia yang memajani manusia setiap hari dalam waktu lama (umumnya lifetime) yang tidak menimbulkan efek merugikan ADI = NOAEL/SF atau LOAEL/SF RfD = NOAEL/(UF x MF) atau LOAEL/(UF x MF)14

EVALUASI EFEK SISTEMIK - 2

RfD = human dose, NOAEL atau LOAEL = experimental dose No Observed Adverse Effect Level: dosis tertinggi toksisitas kronik yang secara statistik atau biologik tidak memperlihatkan efek merugikan Lowest Observed Adverse Effect Level: dosis terendah toksisitas kronik yang secara statistik atau biologik memperlihatkan efek merugikan Safety Factor atau Uncertainty Factor: kelipatan angka 10 untuk menyatakan ketidakpastian & kekurangan data15

REFERENCE DOSE (RfD) - 1

RfD menyatakan risiko nonkarsinogenik dan efek-efek nonkarsinogenik zat karsinogen. RfD adalah estimasi pajanan harian (dengan rentang ketidakpastian satu orde) bagi populasi umum (termasuk subkelompok yang sensitif) yang tidak akan mengalami risiko efek-efek merugikan kesehatan sepanjang hayat.16

REFERENCE DOSE (RfD) - 2

RfD bukanlah direct estimator risiko, melainkan titik rujukan (referensi) untuk menduga efekefek yang potensial (bukan hanya yang aktual). Semakin tinggi pajanan melebihi RfD-nya, semakin besar pula kemungkinan efek-efek merugikan akan terjadi Pajanan di atas RfD seumur hidup tidak berarti dengan sendirinya efek merugikan akan terjadi Pada dasarnya risiko selalu berada di antara pasti tidak terjadi dan pasti terjadi (0