Projection of health risks due to exposure to floodwater pathogens - - PowerPoint PPT Presentation
1 Projection of health risks due to exposure to floodwater pathogens Psyche Fontanos and Kensuke Fukushi TODIAS/IR3S, the University of Tokyo Status of sewerage and sanitation 2 < 2% of population served by sewerage system in Indonesia
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< 2% of population served by sewerage system in Indonesia (Asian Development Bank, 2004)
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Determine the risks of infection from exposure to
Exposure to pathogens through daily activities 3
http://qmrawiki.msu.ed u
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Pathogens in urban floods
Several pathogens cause
It has been shown that the presence of E. coli also indicates the
The indicator in freshwater that correlates best with health
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α α −
/ 1 50
n annual
Beta Poisson model for E. coli（Haas et al., 1999）
where d, dose C, pathogen concentration α, slope parameter = 0.1778 (derived) I, ingestion rate N50, medium infectious dose = 8.6×107 (derived) T, duration of exposure
For single infection risk: For annual infection risk:
where n, number of exposure times per year
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Indirect ingestion of contaminated water through hand to mouth transfer Exposure pathway Exposure pathway Flood water Flood water
Concentration of pathogen (E. coli) in the water environment
Direct ingestion of contaminated water through swimming and swim-like activities
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Inundatio n depth (cm) Non-adults Adults Exposure Pathway Exposure Duration Exposure Pathway Exposure Duration 10 – 50 Indirect ingestion < 20% of time
in contact with water Indirect ingestion < 25% of time
in contact with water 50 - 100 Direct ingestion < 40% of time
in contact with water Indirect ingestion < 50% of time
in contact with water 100 - 200 Direct ingestion < 60% of time
in contact with water Direct ingestion < 75% of time
in contact with water > 200 Direct ingestion < 80% of time
in contact with water Direct ingestion < 100% of time
in contact with water
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Parameter Parameter Symbol, Symbol, unit unit Remarks Remarks Sources Sources Concentration of E. coli CE 8 - 65 x 103 CFU/ml Kido et al (2009); Palupi et al (1995); Phanuwan (2006) Water Ingestion Rate (Indirect ingestion by hand to mouth transfer) Iw, ml/hr Non-adults: 10-50 ml/h Adults :10 ml/h US EPA (2000) Water Ingestion Rate (Direct ingestion) Is,ml/hr Non-adults: 0-205 ml/hr Adults : 0-71 ml/hr Dufour et al (2006) Time spent outdoors T, hr/day 5th - 20; 25th - 60; 50th - 150; 75th - 320; 90th - 511; 95th - 615) US EPA (1997) Fraction of outdoor time spent in water F Non-adults (10-50 cm: up to 20%; 50-100cm: up to 40%; 100-200cm: up to 60%; over 200cm: up to 80%) Adults (10-50 cm: up to 25%; 50- 100cm: up to 50%; 100-200cm: up to 75%; over 200cm: up to 100%) Assumed, varies according to inundation levels Dose-response model N50 = 8.6x107 α = 0.1778 Haas (1999)
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Probabilistic risk
Monte Carlo simulation
Schematic showing the basic principle behind the Monte Carlo Simulation
(http://www.vertex42.com/ExcelArticles/mc/MonteCarloSimulation.html)
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Inundation depth Inundation depth (cm) (cm) Risk of infection Risk of infection (mean) (mean) Total Total Non Non-adults adults Adults Adults Single Single- risk risk1 Annual Annual 10 – 50 0.0019 0.0001 0.0007 0.0086 50 - 100 0.0032 0.0016 0.0021 0.0252 100 - 200 0.0046 0.0023 0.0030 0.0363 > 200 0.0053 0.0877 0.0630 0.542
1 30% of total population is children (AIPA report)
ArcGIS 10.1 by the US
Data provided by JICA
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Land use map
Inundation map
Inundation map
Map of daily risk
Map of daily risk
Clima mate te chan hange ge scena nario rio Urban aniza izatio tion n (%) %) Incre rease ased d rate ate of f rain ainfa fall ( l (%) %) Sea l ea level evel rise ise ( (cm) cm) High igh t tide ide leve evel Land and subsi siden dence ce (m) m) P 62.3 (2008) 39 1.15 0 – 5.9 B1 77.7 (2050) 8 39 1.15 0 – 5.9 A1F1 77.7 (2050) 17 39 1.15 0 – 5.9 Scena nario rio Conte tents nts SQ Status quo scenario The existing flood control infrastructure would be maintained by 2050. MP Master plan scenario The flood control infrastructure in 2050 would be based on the implementation of the existing Master Plan (without the Ciliwung Floodway) MP + PS Master Plan + Strengthening of Pumping station The existing Master Plan would be strengthened with Pumping station by 2050.
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2050_F_MP_A1F1_v0_100 2050_F_MP_A1F1_v2_100
Due to impacts of climate change, inundation area is increased about 8-14% (A&B) Due to land subsidence, inundation area is increased about 15-20% (B&C) A C B
Source: GIS shapefiles from Yachiyo Engineering Ltd.
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Risks of infection from E. coli due to
The risk of infection doesn’t
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