Zeolite, phosphor and titanium containing, crystalline, synthetic, non fibrous

Distribution modelling

Administrative data

Endpoint:

distribution modelling

Type of information:

calculation (if not (Q)SAR)

Remarks:

Migrated phrase: estimated by calculation

Adequacy of study:

other information

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Test procedure is in accordance with generally accepted scientific standards and described in sufficient detail. Due to incorporation of removal of Zeolite A in the wastewater treatment process, the predicted environmental distribution appears realistic, except for a significant underestimation of the fraction in the sediment which is compensated for by an overpredicted fraction in the water. Generally, the application of modelling calculations seems problematic for zeolites as many substance parameters have to be estimated for the model. In reality, it must be assumed that zeolites will settle rather fast to the bottom of aquatic systems, i.e. to the sediment.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Materials and methods

Model:

other: EUSES-exposure simulation according to the HERA scenario

Calculation programme:

EUSES

Model input parameters by user:

Molecular weight (g/mol): 2190
Log Kow: -1 c)
Water solubility (g/l): 0,001 a)
Vapor pressure (Pa): 1 x 10-6 c)
Melting Point (°C): 300 a)
Half-life in Air (d): 1000000 b)
Half-life in Water (d): 63 a)
Half-life in Soil (d): 1000000 b)
Half-life in Sediment (d): 4200000 b)
Temperature (°C): 12

a)=measured b)=default c)=estimated

Input data calculated by the model:
Henry Constant (Pa m³ /mol) 0.00219
Air-Water partitioning coeff.(dimensionless) 9.24E-07
Organic Carbon-Water partitioning coeff.(l/kg) 0.195
Soil Solids-Water partitioning coeff. (l/kg) 0.0039
Sediment Solids-Water partitioning coeff.(l/kg) 0.0098
Suspended Particles-Water partitit.coeff.(l/kg) 0.0195

Media:

air - biota - sediment(s) - soil - water

Test material

Test material information

Constituent 1

Reference substance name:

Zeolite, phosphor and titanium containing, crystalline, synthetic, non fibrous

Molecular formula:

M2/nO [TiO4/2]t [SiO4/2]x [AlO4/2]y [PO4/2]z * wH2O, n is the valence of the cation M, predominantly Na and H, and for both is n=1; x and z can range from 0.25 to 0.75, y and t can range from 0.05 to 0.3 and x+y+z+t=1, and w is the number of water molecules typically between 4 and 40. The composition based on the oxides present in the zeolite is typically: Al: 14-27 % K/Na: <5 % Si: 0.1-5 % P: 12-25 % Ti: 0.05-5 %

IUPAC Name:

Zeolite, phosphor and titanium containing, crystalline, synthetic, non fibrous

Results and discussion

Any other information on results incl. tables

The results obtained in the EUSES calculations are shown in Table 1.

Table 1: Concentrations and distribution of Zeolite A in the four dominant media based on Level III calculations
-----------------------------------------------------------
                                               Concentration (PEC)  Distribution
                                               [mg/l][mg/kg]                [%]
-----------------------------------------------------------
Natural soil (total)                       2.66E-03        0.08%
Agricultural soil (total)       1.1                  59.7%
Industrial/urban soil (total)               0.00266           0.01%
Surface Water (total)                          0.75                     39.9%
Sediment (total)                   0.45                     0.31%
atmosphere                                  1.02E-06 0.00%
-----------------------------------------------------------