Hämeenkyrö MSWI risk assessment: Dioxin
See the main page of this assessment: Hämeenkyrö MSWI risk assessment: General
Contents
Dioxin emissions in Hämeenkyrö
Virpi
| Focus: | Dioxin emissions in Hämeenkyrö |
| Scope: | Annual dioxin emissions in the area of Hämeenkyrö municipality from the relevant sectors (involving both current sources, as well as the possible future sources considering the different decisions on the MSWI). |
| Description: | The name dioxin is used for the family of structurally and chemically related polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF), and certain polychlorinated biphenyls (PCBs). Some 419 types of dioxin-related compounds have been identified, and about 30 of these are considered to have significant toxicity.
Dioxins are produced unintentionally as by-products of many chemical industrial processes and of all combustion processes. Sources include metal industry, power plants, industrial combustion plants, small combustion units (mostly domestic), waste incineration, road transport and mineral products production. Total dioxin emissions are usually reported in toxic equivalency values (TEQ), which enables comparison of the toxicity of different combinations of dioxins and dioxin-like compounds. A TEQ is calculated by multiplying the actual grams weight of each dioxin and dioxin-like compound by its corresponding toxic equivalency factor (TEF) and then summing the results. The number that results from this calculation is referred to as grams TEQ. (Comment: The emissions sources of dioxin are known pretty well. Although it is unlikely that these factories have direct dioxin measurements, emission estimates for the sources of this size should be available. You should ask Juhani Ruuskanen (KuY) or Päivi Ruokojärvi (KTL)). Possible dioxin sources in Hämeenkyrö: Currently: the local gas power plant, traffic, domestic combustion (cardboard factory, sawmill) D↷ Future: Municipal solid waste incinerator, biofuel power plant
Low technology combustion, no APC system: air 3500, fly ash 0, bottom ash 75 Controlled combustion, minimal APC: air 350, fly ash 500, bottom ash 75 Controlled combustion, good APC: air 30, fly ash 200, bottom ash 7 High technology combustion, sophisticated APC system: air 0.5, fly ash 15, bottom ash 1.5
Natural gas fired power boiler: 0.5 Mixed biomass fired power boiler: air 500, residue 0 Clean wood fired power boiler: air 50, residue 15
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| Inputs: | Kyro gas power plant, MSWI in Hämeenkyrö, biofuel power plant in Hämeenkyrö, landfills, fires on landfill areas, waste transport |
| Index: | |
| Definition: | |
| Unit: | g I-TEQ/a |
| Result: | |
| References: | UNEP (1999). United Nations Environment Programme. Dioxin and furan inventories, National and regional emissions of PCDD/PCDF, May 1999.
SYKE 2004. Finnish Environment Institute. Air pollutant emissions in Finland 1990-2002. National inventory report. http://www.ymparisto.fi/download.asp?contentid=13512#search=%22dioxine%20emissions%20from%20traffic%22 |
Intake fraction for dioxin emissions from Hämeenkyrö
| Focus: | Intake fraction for dioxin emissions from Hämeenkyrö |
| Scope: | Emission from a high stack in Hämeenkyrö, exposed population anywhere in Europe. Long-term exposure, includes accumulation in food chain. 'Dioxin' means TEQs of all 17 toxic congeners, not only TCDD. |
| Description: | Intake fraction (iF) means the fraction of an emission that is finally inhaled or ingested by a target population. The exposure to dioxins occur after a multistep process. First, dioxins are emitted into the atmosphere often due to a combustion process. Dioxins are persistent molecules and can transfer hundreds or thousands of kilometres before depositing to water, vegetation, or soil. It absorbs tightly onto surfaces, and therefore it is rather inert if adsorbed to soil. However, when dioxins deposit to water, they enter the aquatic food chain and end up to fish. When they deposit on grass fields or crop, they typically enter the cattle feed and then milk or meat. Because of this long process including accumulation in food chain, the dioxin exposure of a population is mostly derived from other than local sources.
Margni and coworkers have estimated an iF for Western European sources. The iF is approximately 3.5.10(-3) for emissions of dioxin in Western Europe. This iF compares well to the traditional non-spatial multi-media/-pathway model predictions of 3.9.10(-3) for the same region and to 2.10(-3) for the USA. Approximately 95% of the intake from Western European emissions occurs within the same region, 5% being transferred out of the region in terms of food contaminants and atmospheric advective transport. (Margni et al., 2004) However, when the emission source is in the North-Eastern corner of Europe like Hämeenkyrö is, the population exposed is likely smaller than on average, especially because the predominant wind direction is from southwest and away from densely populated areas. Therefore, the published value is likely an overestimate. |
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| Unit: | - |
| Result: | 3.5*10-3 |
| References: | Margni M, Pennington DW, Amman C, Jolliet O. Evaluating multimedia/multipathway model intake fraction estimates using POP emission and monitoring data. Environ Pollut. 2004;128(1-2):263-77. Bennett DH, Margni MD, McKone TE, Jolliet O. Intake fraction for multimedia pollutants: a tool for life cycle analysis and comparative risk assessment. Risk Anal. 2002 Oct;22(5):905-18. |
Baseline dioxin exposure in Hämeenkyrö
Marjo
| Focus: | Baseline dioxin exposure in Hämeenkyrö inhabitants |
| Scope: | The daily intake and the adipose tissue concentration of polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/Fs) and biphenyls (PCBs) in Hämeenkyrö population |
| Description: | Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs, "dioxins") are ubiquitously present, stable and persistent environmental contaminants. They are fat soluble and thus tend to bioaccumulate in tissue lipid and in the food chain. More than 90 % of the average human intake of dioxins originates from food, especially food of animal origin. In Finland the main source is fish, whose contribution is 72-94 % of the total PCDD/F intake via food.
Here we will use the daily PCDD/F intake estimated for the Finnish population in average as a starting point. In addition, the other variable in this model, "Dioxin emissions in Hämeenkyrö", may affect the estimate of baseline dioxin exposure in Hämeenkyrö. For the adipose tissue PCDD/F concentration the value estimated for the general population living in Finnish inland is used. It is noteworthy, that some subgroups within society, such as nursing babies and people consuming lot of fish may be more highly exposed to dioxins than the average people. PCBs, another group of persistent environmental contaminants, were included as they behave similarly in the food chain and have partly similar health effects as dioxins.D↷ |
| Inputs: | Dioxin emissions in Hämeenkyrö
Intake fraction for dioxin emissions from Hämeenkyrö |
| Index: | |
| Definition: | |
| Unit: | 1) Daily intake: WHO-TEQ pg/kg body weight
2) Adipose tissue concentration: WHO-TEQ pg/g fat |
| Result: | Average daily intake of PCDD/Fs 0.79 pg/kg bw
Average daily intake of PCBs 0.74 pg/kg bw Average adipose tissue PCDD/F concentration 26.4 pg/g Average adipose tissue PCB concentration 18.1 pg/g Note: During the nursing period, the PCDD/F intake of a child can be 1-2 orders of magnitude higher than that of an adult. |
| References: | Holtta P, Kiviranta H, Leppaniemi A, Vartiainen T, Lukinmaa PL, Alaluusua S. Developmental dental defects in children who reside by a river polluted by dioxins and furans. Arch Environ Health. 2001 Nov-Dec;56(6):522-8.
Kiviranta H, Ovaskainen ML, Vartiainen T. Market basket study on dietary intake of PCDD/Fs, PCBs, and PBDEs in Finland. Environ Int. 2004 Sep;30(7):923-32. Kiviranta H, Tuomisto JT, Tuomisto J, Tukiainen E, Vartiainen T. Polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls in the general population in Finland. Chemosphere. 2005 Aug;60(7):854-69. Tuomisto et al. 1999. Synopsis on dioxins and PCBs. Publications of the National Public Health Institute B17/1999. |
Dioxin exposure due to MSWI in Hämeenkyrö
Martin
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Health effects caused by dioxin exposure
Sanna
| Focus: | Determine health effects caused by dioxin exposure D↷ |
| Scope: | General population average considered. Accidental local releases excluded
(Comment: This would rather go to the variable Dioxin emissions in Hämeenkyrö). |
| Description: | Dioxins are persistent environmental contaminants which accumulate and their elimination half life in the body
is rather high (~7 years). In the exposure low doses and high doses cause totally indifferent effects. Most probable exposures for humans from MSWI are low dioxin exposures for a long period of time, which may affect the population "background exposure levels" by increasing them. The most susceptible subgroups among human population are children and young females (women at the childbearing age and before) in addition to the subgroups in the occupational hazard or those who may get high exposures via the food (fishermen).
of accidental exposure is low; only if the burning process is working improperly the amount of dioxin emissions will increase.
and dioxins are probably quite weak carcinogens in humans. Data exist which supports the hypothesis of hormesis type of dose-responses (Tuomisto et al., 2004) in cancer.
daily intake (TDI) is set in a range of 1-4 pg TEQs/kg bodyweight/day.
study by Alaluusua et al. (1996). In a study by Miettinen et al. (2005) exposure to 0.5 μg TCDD/kg body weight on GD 15 resulted in maternal adipose tissue concentration 2185 pg/g fat. In that study linear extrapolation of the data predicts a maternal adipose tissue concentration of 100-120 pg/g fat after exposure to 0.03 μg TCDD/kg body weight. This estimated maternal adipose tissue concentration which is sufficient to induce developmental dental defects in rat offspring, is similar to the highest values measured in the Finnish average population (PCDD/F 145.5 pg WHO-TEQ/g fat, Kiviranta et al. 2005). |
| Inputs: | *Dioxin emissions and in Hämeenkyrö (Comment: This is not actually an input, but [[#Dioxin exposure due to
MSWI in Hämeenkyrö]]
demographic data (Comment: This background variable is actually missing: Anne knows about the population size, but does someone know about the background disease rates?) |
| Index: | |
| Definition: | |
| Unit: | increased developmental defects/ pg/kg body weight/ year,
increased cancer per pg/kg body weight OR per adipose tissue concentration (Comment: units are good for exposure-response function (as this variable used to be) but not for health effect (as it currently seems to be) |
| Result: | |
| References: | Tuomisto JT et al. Int J Cancer. 2004 Mar 1;108(6):893-900.
Tuomisto et al. 1999. Synopsis on dioxins and PCBs. Publications of the National Public Health Institute B17/1999. van Leeuwen FX et.al. Chemosphere. 2000 May-Jun;40(9-11):1095-101. Alaluusua et al. Eur J Oral Sci. 1996 Oct-Dec;104(5-6):493-7. Miettinen HM et al. Toxicol Sci. 2005 Jun;85(2):1003-12. Kiviranta et al. Chemosphere. 2005 Aug;60(7):854-69. |