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Exposure Assessment by Multi-media modelling. Cause-effect chain for ecosystem and human health as basis for exposure assessment by multi-media modelling (Fairman et al., 1998). CalTOX CalTOX is a multimedia, multiple pathway exposure, transport and transformation model.

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Exposure Assessment by Multi-media modelling

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Exposure assessment by multi media modelling

  • Exposure Assessment by

  • Multi-media modelling


Exposure assessment by multi media modelling

  • Cause-effect chain for ecosystem and human health as basis for exposure assessment by multi-media modelling (Fairman et al., 1998)


Exposure assessment by multi media modelling

  • CalTOX

  • CalTOX is a multimedia, multiple pathway exposure, transport and transformation model.

  • Applications Limitations

  • Site-specific: local

  • Time scale : from one year to decades.

  • Substances assessable : non-ionic organic chemicals, radionuclides, fully dissociating in-/organic chemicals, solid-phase metal species, partially dissociated in-/organic species,

  • Available together with information and documentation via the Internet through page:

    (http://www.eetd.lbl.gov/ied/era ( version4.0):


Exposure assessment by multi media modelling

The eight compartment model of CalTOX


Exposure assessment by multi media modelling

Compartments considered in the model:

  • air

  • plants

  • ground-surface soil

  • root-zone soil

  • vadose-zone soil

  • ground water

  • surface water

  • sediment


Exposure assessment by multi media modelling

The structure of the CalTOX model with the multimedia transport, the intermedia transfer and its exposure pathways


Exposure assessment by multi media modelling

23 pathway human exposure scenario:

  • All inhalation exposures indoors active

  • All inhalation exposures indoors resting

  • Inhalation exposure in shower/bath

  • Inhalation exposures outdoors active

  • Inhalation of air particles indoors

  • Transfer of soil dust to indoor air

  • Transfer of soil vapors to indoor air

  • On-site inhalation by animals


Exposure assessment by multi media modelling

Water

  • Use of ground water as tap water

  • Use of surface water as tap water

  • Ingestion of tap water

  • Use of ground water for irrigation

  • Use of surface water for irrigation

  • Use of ground water for feeding animals

  • Use of surface water for feeding animals


Exposure assessment by multi media modelling

Plants

  • Contaminant transfer, air to plants surfaces

  • Contaminant transfer, ground soil to plant surfaces

  • Contaminant transfer, root soil to plant tissues

  • On-site grazing of animals

    Human Ingestion

  • Ingestion of home-grown exposed produce

  • Ingestion of home-grown unexposed produce

  • Ingestion of home-grown meat

  • Ingestion of home-grown milk

  • Ingestion of home-grown eggs

  • Ingestion of locally caught fish

  • Direct soil ingestion


Exposure assessment by multi media modelling

Dermal

  • Soil contact exposure at home or at work

  • Dermal exposure during shower/bath

  • Dermal & ingestion exposures while swimming

    Infants

  • Breast-milk ingestion by infants.


Exposure assessment by multi media modelling

  • Input data of CalTOX

  • Data describing the substance

  • Physico-chemical properties

  • Measured emissions into the compartments

  • Background concentrations of the contaminant

  • Toxicological properties, consisting of a cancer and a non-cancer potency for human beings, since only human risk is considered in CalTOX.


Exposure assessment by multi media modelling

Data characterising the area:

  • Geographical data like the contaminated area size

  • Meteorological and hydrological data, e.g. the average depth of surface water, the annual average precipitation, wind speed or environmental temperature

  • Soil properties, like the organic carbon fractions

  • Data about the human population, e.g. the average body weight or daily intake rates for different kinds of food.


Exposure assessment by multi media modelling

  • Output data of CalTOX

    Predicted concentrations in:

  • breast milk

  • fish

  • milk

  • meat

  • eggs

  • tap water

  • swimming water


Exposure assessment by multi media modelling

Estimated exposure media concentrations

  • indoor air

  • outdoor air

  • bathroom air

  • tap water

  • swimming water

  • un-/exposed produce

  • meat

  • milk

  • eggs

  • fish and seafood

  • household soil


Exposure assessment by multi media modelling

  • Some properties like fugacity capacities or boundary layer thickness in different media are also calculated.

    Daily human doses by:

  • inhalation,

  • ingestion (breast milk, water, milk, meat, fish, soil)

  • dermal uptake


Exposure assessment by multi media modelling

Final results:

  • Individual human lifetime Risk for developing cancer

    Risk = chronic daily intake * slope factor

  • Hazard ratio for non-carcinogenic effects attributable to exposure over a certain period which can be defined by the user.

    Hazard ratio = intake/reference dose


Exposure assessment by multi media modelling

  • Inputs used in CalTOX

  • Physico-chemical properties

  • Molecular weight

  • Melting point

  • Vapour pressure

  • Water solubility

  • Henry's law constant

  • Octanol-water partition coefficient (KOW)

  • Organic carbon-water partition coefficient (KOC)

  • Degradation rates

  • Half-life time in air

  • Half-life time in water

  • Half-life time in sediment

  • Half-life time in soil

  • Emission to regional air

  • Emission to regional surface water

  • Regional emissions to soil


  • Exposure assessment by multi media modelling

    Time

    - Averaging time

    - Exposure duration

    Area description

    - Area

    - Average wind speed

    - Average annual precipitation

    - Average environmental temperature

    Humans description

    - Egg intake

    - Grain intake

    - Fruit and vegetable intake

    - Milk intake

    - Fish intake

    - Meat intake

    - Body weight


    Exposure assessment by multi media modelling

    Accumulation behaviour

    - Bioconcentration factor for fish

    - Cancer potency factor

    - Non-cancer ADI


    Exposure assessment by multi media modelling

    Predicted concentrations in environmental media:

    airair (gases)

    air (particles)

    (annual) average in air (total)

    soilground soil

    root zone soil

    vadose zone soil

    off-site surface soil

    ground water

    surface water

    annual average in surface water

    sedimentsediment

    aquifer


    Exposure assessment by multi media modelling

    • Predicted concentrations in exposure mediaCalTOX

      • plants/grass

      • fish/seafood

      • meat

      • milk

      • drinking water

      • eggs

      • breast milk

      • swimming water

      • indoor air

      • bathroom air

      • outdoor air

      • household soil


    Exposure assessment by multi media modelling

    • DosesCalTOX

    • Daily human doses through intake of

      • drinking water

      • air

      • fish

      • meat

      • milk

      • total

      • eggs

      • soil

      • breast milk (infants)

    • daily inhalation by humans of

      • surface soil

      • root-zone soil

      • ground water

      • surface water

      • total


    Exposure assessment by multi media modelling

    • Daily dermal uptake by humans from

      • surface soil

      • root-zone soil

      • ground water

      • surface water

      • total


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