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Cost efficiency of remediating arsenic-contaminated sites in sweden
Cost efficiency of remediating arsenic-contaminated sites in sweden
Cost efficiency of remediating arsenic-contaminated sites in sweden
Cost efficiency of remediating arsenic-contaminated sites in sweden
Cost efficiency of remediating arsenic-contaminated sites in sweden
Cost efficiency of remediating arsenic-contaminated sites in sweden
Cost efficiency of remediating arsenic-contaminated sites in sweden
Cost efficiency of remediating arsenic-contaminated sites in sweden
Cost efficiency of remediating arsenic-contaminated sites in sweden
Cost efficiency of remediating arsenic-contaminated sites in sweden
Cost efficiency of remediating arsenic-contaminated sites in sweden
Cost efficiency of remediating arsenic-contaminated sites in sweden
Cost efficiency of remediating arsenic-contaminated sites in sweden
Cost efficiency of remediating arsenic-contaminated sites in sweden
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Cost efficiency of remediating arsenic-contaminated sites in sweden

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Written and prepared by me Hafez Shurrab. This report reviews an analysis to the one of environmental issues that cost-efficiency plays a significant role in.

Written and prepared by me Hafez Shurrab. This report reviews an analysis to the one of environmental issues that cost-efficiency plays a significant role in.

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  • 1. Cost-Efficiency of RemediatingArsenic-Contaminated Sites inSweden - Written & Prepared by Hafez Shurrab
  • 2. ABSTRACT This report reviews an analysis to the one of environmental issues that cost-efficiency plays a significant role in. Many remediating activities are carried out by theSwedish government to reduce the effects of contaminants by the industrial activities onthe environment and human health. The risk analysis the Swedish EFA adopts is anexplicit one that compares the levels of contaminants concentrations in each site topredetermined guideline values. The analysis reviewed in the report discusses an implicitapproach, environmental medicine approach, which considers the actual exposure to therisk, and therefore, the reduction in the risk to human health could be quantified and thenstudied to examine several alternatives that may lead to more cost-efficient outcomes.The analysis is based on studying 23 arsenic-contaminated sites, as arsenic is classified asa primary contaminant. The reduction of risk is measured by the number of saved lives,which implies that the risk assessment method is driven by health effects. The resultsindicate that at 23 contaminated sites, the cost per life saved varies from SEK 287 millionto SEK 1,835,000 million, and show that the level of ambition is high. Thus, it isrecommended to open deep discussions on cost-efficiency methods of risk assessmentbefore going further any remediation, to achieve the objective in more cost-efficientways, prioritize the right sites that have more hazardous levels, and increase the numberof lives to be saved allocating similar amounts of resources. I
  • 3. TABLE OF CONTENTSABSTRACT ................................................................................................................................ ITABLE OF CONTENTS ...........................................................................................................IILIST OF TABLES .....................................................................................................................II1. INTRODUCTION ..........................................................................................................- 1 -2. BACKGROUND ............................................................................................................- 2 -3. THEORY ........................................................................................................................- 3 - 3.1. Arsenic Concentrations ....................................................................................................... - 4 - 3.2. Exposure .............................................................................................................................. - 5 - 3.3. Accessibility and Land Use ................................................................................................. - 5 -4. METHODOLOGY .........................................................................................................- 5 - 4.1. Risk Assessment .................................................................................................................. - 5 - 4.2. Calculating the Number of Cancer Cases Avoided ............................................................. - 6 -5. RESULTS .......................................................................................................................- 7 -6. CONCLUSIONS.............................................................................................................- 9 -1. REFERENCES .............................................................................................................- 10 - LIST OF TABLESTable 1 - The cost per life saved for primary prevention measures .......................................- 2 -Table 2 - Site-specific characteristics.....................................................................................- 3 -Table 3 - Site-specific characteristics.....................................................................................- 4 -Table 4 - Quantified cancer risks, descriptions and sources. .................................................- 7 -Table 5 - Number of saved lives, costs and comparisons ......................................................- 8 - II
  • 4. 1. INTRODUCTION Some of industrial activities leave pollutants that have serious impacts on humanhealth and the environment. The level of pollutants varies among the contaminated sites.Since there are sites that have the seriously harmful levels of pollutants to human healthand the environment in terms of contaminant concentrations, the Swedish EnvironmentalProtection Agency (EPA) has prioritized 1500 sites to be remediated as part of striving tomitigate the risk to human life. A plan has been set so that all those contaminated siteshave to be remediated by 2050. The most harmful sites required remediation may costSEK 60,000 million approximately cost to mitigate the potential risks (Swedish EPA,2008). The government allocates around 10% of the annual national funds forenvironmental protection to remediate the contaminated sites, which are estimated atabout 455million per year (Gov. Bill, 2007). The Swedish EPA adopts a method of riskassessment in which they set standards (guideline values) that represent the worstacceptable exposure situation to risk on an individual. This means that the actualexposure to the risk by individuals in such sites is not the main concern, which may resultin remediating locations where there is no actual exposure, and hence spending muchmoney ineffectively. The valuation of risk reduction is not possible in this case, since theexpected risk is not quantified. Therefore, the estimation of how much money a specificamount of risk reduction costs is not possible. The main objective of this paper is to review an analysis (Forslund et al., 2010) onthe remediation of arsenic-contaminated by valuing the risk implicitly. The effect to bestudied is the cancer cases that arsenic-contaminated sites may cause (Forslund et al.,2010). The main purpose is to see the arsenic risk management in wider perspective oflive-saving interventions. The large risks should not be given a same attention as smallrisk. The remediation of contaminated sites cost much money. Thus, any overestimationof risk on lifesaving contributes in reducing the cost-effectiveness. Lifesaving is used as ameasure to reflect the amount of reduced risk. The analysis includes a method for theestimation of site-specific cancer risks and calculations of cost per life saved. The resultsshow that the remediation costs much higher per life saved than that associated with otherprimary prevention measures, which indicates that the ambition level of Swedishremediation may be too high. -1-
  • 5. 2. BACKGROUND One of the most important issues in cost-effectiveness is the resources allocation. Itis very critical to spend money so that to save as many lives as possible. Since the lifevaluation is controversial issue, the analysis is based on estimating the number of savedlives implicitly, rather than using some predetermined explicit values. The average costof lifesaving varies from USD 470 to USD 1,245,000 (in 1993 prices) (Ramsberg &Sjöberg, 1997). Table 1 shows the cost per life saved for primary prevention measures.The implicit cost per life saved is, on average, SEK 66.6 million, with a large variationamong different sectors from SEK 68,000 to SEK 675 million. The median cost per lifesaved is approximately SEK 12 million. The comparison between such method and theguideline values, the Swedish EPA uses, shows that there are 100–1000 times higheraccepted risks in working and housing environment than contaminated sites (Rosén et al,2006).Table 1 - The cost per life saved for primary prevention measures in Swedish crowns, SEK (2007prices) (source: (Forslund et al., 2010)). The allocation of resources is considered to be cost-efficient when the marginal costis equal to the abatement cost (interventions). Thus, if the marginal costs differ, resourcesshould be reallocated to the sector with the lowest marginal costs. It would be possible inthe US to save an additional 60,000 lives per year through a more cost efficient allocation(Tengs & Graham, 1996). -2-
  • 6. 3. THEORY The government gives the priority to sites, out of the 1500 contaminated sites,contaminated with the most hazardous contaminants, which are called primarycontaminants. Arsenic (26%) has been identified as the most hazardous carcinogenic(IARC, 2004, 2008) contaminant among other metals. Table 2 & 3 lists the 23 arsenic-contaminated sites with either completed (10 sites) or on-going measures (13 sites). The exposure to arsenic increases the risk of developing cancer (U.S. Department ofHealth and Human Services, 2007). There are many industrial activities that producearsenic contaminants such as glasswork and sulphate and metal industries, woodimpregnation, and from sawmill.Table 2 - Site-specific characteristics (source: (Forslund et al., 2010)). -3-
  • 7. Table 3 - Site-specific characteristics (source: (Forslund et al., 2010)).3.1. Arsenic Concentrations Since the exposure to arsenic is a harmful in the long term, the arsenic concentrationshave been collected before the remediation to estimate the average concentrations ofarsenic in the 23 sites (Forslund et al., 2010). The remediation should reduce suchconcentrations to specific safe limits. There are some factors that play a significant role inthe determination of safe limits of arsenic concentration such as the number ofindividuals exposed, geographical locations of the sites, the accessibility (open orenclosed), and the land use (housing, recreation, or industry) (Forslund et al., 2010). Asshown in Table 2 & 3, there safe limit of objectives of the average concentrationcorrespond the Swedish EPAs guideline values for either sensitive, i.e. 15 mg/kg, or lesssensitive, i.e. 40 mg/kg, land use (Forslund et al., 2010). -4-
  • 8. 3.2. Exposure The exposure is estimated by gathering information about the individual population,which is of course available in the municipal bodies. The population of individualsexposed to the contaminated sites is divided into three classes, 1–10, 10–100 and 100–1000. Other types of information have been gathered such as the land use and the numberof children aged from 0-3 years (Forslund et al., 2010).3.3. Accessibility and Land Use As the accessibility to the contaminated sites is divided into open or enclosed sites,the daily exposure is estimated to be 1 h for recreational activities, 24 h for individualsresiding on or adjacent to a site, and 5.7 h for occupational activities. In case that thesefactors are neglected, the underestimation possibility of risk for some sites results inoverestimating the number of lives saved, and, in other words, underestimating the costper life saved (Forslund et al., 2010).4. METHODOLOGY The cost-effectiveness analysis is a primary part in the overall analysis, as theenvironmental effects were not quantified by the Swedish EPA. Moreover, the cost-benefit analysis is also important to include other environmental benefits may be broughtby the remediation (Forslund et al., 2010).4.1. Risk Assessment The main task of risk assessment is to determent the levels of arsenic exposure andtheir effects on the environment and human health when additional contaminant resourcesare present. The Swedish EPA classifies risk through estimating the contaminant level inthe site, site’s environmental sensitivity, and protection value (Swedish EPA, 2002). Theguideline values for contaminant are compiled in the soil for different for different typesof land use, to make the risk assessment more obvious. These are national values andmark the levels that should not be exceeded. The sub questions arise then are what humanhealth risks arise at a specific level of exposure and what the actual exposure is at aspecific site (Forslund et al., 2010). The health risk assessment could be estimated by referring to the tolerably dailyintake (TDI) that World Health Organization and other international bodies recommend. -5-
  • 9. The TDI refers to the daily amount of a chemical that has been assessed safe for humanbeing on long-term basis (usually whole lifetime) (Forslund et al., 2010). There are twocategories for the sensitivity of land use, sensitive and less sensitive. For sites with lesssensitive land use, the types of exposure or exposure pathways include dermal contactwith contaminated soil, direct intake of contaminated soil and inhalation of dust from thecontaminated site. The relevant exposure pathways for sites with sensitive land aredermal contact, direct intake of soil, intake of groundwater, inhalation and intake ofvegetables and fish. The Swedish EPA uses a precautionary principle to handle alluncertainties in the risk assessment. In order not to underestimate the risks, threeconsiderations are taken including: (1) the contaminant levels should represent a ‘bad butpossible scenario; (2) possible but less probable circumstances that could increase therisks are considered; and (3) conservative values should be chosen for the parameters inthe risk assessment (Swedish EPA, 2007). The Swedish EPA does not quantify the expected risk reduction, which leads to aneed to value the risk before and after the remediation in terms of relevant measure, forinstance the number of cancer cases avoided (Forslund et al., 2010). There are two main differences between guideline values approach, the SwedishEPA adopts, and the medicine approach. The later one assesses the health risk to a largerextent, but over shorter time period, two decades, while the Swedish EPA aims to strivesfor long-term sustainability and argues that 100–1000 years should be considered(Liljelind & Barregard, 2008). Another difference is that environmental medicine treatshigh concentrations of contaminants on the surface more seriously than contaminantsdeeper down that humans normally do not risk being exposed to, except for the case ofingestion of ground water (Forslund et al., 2010).4.2. Calculating the Number of Cancer Cases Avoided The analysis studies the exposure through pathways including ingestion of soil,inhalation of air, and skin contact, since the exposure through intake of vegetables is notrelevant for the contaminated sites, and the exposure through ingestion of groundwater islimited to two of the sites. The exposure through all pathways is considered forcalculations. Every pathway has different method of calculation. For skin contact case,the assumptions for skin absorption percentage when contacting an amount of soil guidesto draw calculations for the exposure to arsenic. The reaction between the type of soil and -6-
  • 10. the air is assumed and studied to estimate the concentration of arsenic in air particles. Foringestion of soil, the arsenic exposure is calculated based on assumptions of the amountof intake during the exposure time. The uncertainties are expressed about in intervals ofcertain factor so that the values of the intervals lead to the highest exposure, whichimplies that the calculations are conservative. Using different method, the number ofsaved cancer cases would be several times lower if mid-interval estimates are consideredinstead (Forslund et al., 2010). The calculations are done in two steps, as the number ofsaved cancer cases are calculated in case of the absence of the remediation for 30 years(Viscusi et al., 1997). Then the risk is estimated in case of the presence of remediation,according to the Swedish EPAs guideline values. The number of lives saved should beadjusted since not all cancer cases lead to death. Since the future cancer cases areunknown, they are not discounted (Hamilton & Viscusi, 1999). Table 4 shows thequantified cancer risks in terms of concentration for each exposure pathway.Table 4 - Quantified cancer risks, descriptions and sources (source: (Forslund et al., 2010)).5. RESULTS After doing the calculations to the 23 sites, the results illustrated in Table 5 showsthat the highest value of expected number of saved lives through the remediation are 0.03live, 0.12 lives in total SEK 881 million. The cost per life saved on the arsenic sites variesfrom SEK 287 million to SEK 1,834,000 million (Forslund et al., 2010). This widelyexceeds the value of a statistical life (VSL), which in Sweden is considered to be aboutSEK 21million (SIKA, 2005). One more significant note is that 72% of the health effectsoccur at three sites (Tvärån, Glasbrukstomten, Konsterud), where remediation costsamount to 13% of the total remediation costs, which clearly shows the priority concern in -7-
  • 11. the remediation work. The average cost is calculated as the quotient between the totalremediation cost and the total number of cancer cases avoided (or lives saved). Thenumber of individuals need to be exposed at each site in order for one life to be saved iscalculated as well, which results that of individuals exposed should increase from 10–1000 to 2850–620,000 individuals. Such populations exceed the number of inhabitants inthe municipality in some cases. The calculations also reflect that the ambition level inremediation is high, and in some cases unreasonably high. There may be other concernsassociated with the other risks arsenic may cause such as chronic diseases. Theenvironmental risks differ among sites and are very difficult to estimate and value. Thisanalysis explains why the cost per life saved varies so much between the sites.Differences in environmental risk reductions between the sites could be one of the mainreasons for variety (Forslund et al., 2010).Table 5 - Number of saved lives, costs and comparisons (source: (Forslund et al., 2010)). -8-
  • 12. 6. CONCLUSIONS The remediation of the contaminated sites is a complicated process and associatedwith many considerations. The Swedish EPA should adjust both the priorities given to thesites and the level of ambition. The most hazardous sited should be prioritized. The costper life for the examined sites under a 30 year period amounts varies between SEK 287million and SEK 1,835,000 million even though the calculations underestimate the cost.The statistical life value amount to SEK 21 million (SIKA, 2008), while the average costper life saved amounts to SEK 7200 million, which is very high. It is highlyrecommended to conduct a discussion about the allocation of resources across differentsectors to save lives. For the number of lives to be saved, the results shows that no morethan 0.12 lives will be saved during a 30 year period at a cost of SEK 880 million. Theapproach that the Swedish EPA adopts in risk assessment is setting guideline values andthen assesses whether the contaminant concentrations exceed these values, while theactual exposure at risk is not really taken into considerations. As there is absence ofestimating the reductions of remediations risk, it is not possible then to quantify theremediation benefits. This explains the low cost-efficient measures of remediation theSwedish EPA adopts, as they are more costly measures than needed to reach acceptablerisk levels. This justifies the need to use a new method for making risk valuations. -9-
  • 13. 1. REFERENCES IARC Working Group on the Evaluation of Carcinogenic Risks to Humans. (2004). Some drinking-water disinfectants and contaminants, including arsenic (Vol. 84). World Health Organization. IARC. (2008). Overall evaluations of carcinogenicity to humans. International Agency for Research on Cancer. Forslund, J. Samakovlis E. Johansson M., & Barregard L. (2010). Does remediation save lives? — On the cost of cleaning up arsenic-contaminated sites in Sweden. Science of the Total Environment. 408 (16), 3085-3091. Gov. Bill (2007). Budgetpropositionen för 2008. Hamilton, J. T., & Viscusi, W. K. (1999). Calculating risks?: The spatial and political dimensions of hazardous waste policy (Vol. 21). MIT Press. Liljelind I. Barregard L. (2008). Hälsoriskbedömning vid utredning av förorenade områden. Swedish Environmental Protection Agency Report (Vol. 5859). Ramsberg, J. A., & Sjöberg, L. (2006). The cost-effectiveness of lifesaving interventions in Sweden. Risk Analysis, 17(4), 467-478. Rosén, L. Söderqvist, R. Soutukorva, Å. Back, P-E. Grahn, L., & Eklund, H. (2006). Riskvärdering vid val av åtgärdsstrategi. Swedish Environmental Protection Agency Report (Vol. 5537). SIKA. (2005) Effektiva styrmedel för säkrare vägtrafik, 8. Swedish Institute for Transport and Communications Analysis PM 2005. Swedish EPA. (2002). Methods for inventories of contaminated sites. Swedish Environmental Protection Agency Report (Vol. 5053). Swedish EPA. (2007). Rapport riskbedömning av förorenade områden—En vägledningfrån förenklad till fördjupad riskbedömning. Swedish Environmental Protection Agency. - 10 -
  • 14. Swedish EPA. (2008). Lägesbeskrivning av efterbehandlingsarbetet i landet 2007 —Bilagor. Swedish Environmental Protection Agency official document.Tengs, T., & Graham, JD. (1996). The opportunity cost of haphazard social investmentsin life-saving. In: Hahn, RW. Risks, costs and lives saved. New York: Oxford UniversityPress.U.S. Department of Health and Human Services. (2007). Toxicological profile forarsenic. Public health Service, Agency for Toxic Substances and Disease Registry.Viscusi, W. K., Hamilton, J. T., & Dockins, P. C. (1997). Conservative versus mean riskassessments: Implications for Superfund policies. Journal of environmental economicsand management, 34(3), 187-206. - 11 -

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