Input data for NORMTOX
Standards and ADIs
The table below lists the standards and ADIs/TDIs used to test the coherence of chlorfenvinphos, mercury and nitrate, including their original sources.
Chlorfenvinphos / Mercury / Nitrate / Units / Source(s)Oral ADI/TDI (ADIoral) / 5,00E-01 / 7,20E-01 / 3,40E+03 / µg/kg body.dag / 1,2,3
Inhalatory ADI/TDI (ADIinhalatory) / not available / 3,00E-01 / not available / µg/m3 / 1,2,3
Soil quality objective (EQOsoil) / 6,00E-05 / 1,00E+01 / not available / mg/kg / 4
Water quality objective (EQOw) / 2,00E-03 / 1,20E+00 / not available / µg/l / 4
Air quality objective (EQOair) / not available / 9,00E-02 / not available / µg/m3 / 4
Drinking water quality objective (EQOdw) / 1,00E-01 / 1,00E+00 / 5,00E+01 / µg/l / 5
Food quality objectives* (EQOfp)
potatoes (EQOpotatoes) / 5,00E-01 / 2,00E-02 / not available / mg/kg product / 6,7
vegetables (EQOveg) / 1,99E-01 / 2,79E-02 / 5,11E+02 / mg/kg product / 6,7
fruit (EQOfruit) / 2,60E-01 / 1,00E-02 / not available / mg/kg product / 6,7
grain (EQOgrain) / 5,00E-02 / 3,00E-02 / not available / mg/kg product / 6,7
meat (EQOmeat) / 2,00E-02 / 5,00E-03 / not available / mg/kg product / 6,7
eggs (EQOeggs) / 5,00E-02 / 3,00E-02 / not available / mg/kg product / 6,7
milk & milk products (EQOmilk) / 8,00E-03 / 1,00E-02 / not available / mg/kg product / 6,7
cheese (EQOcheese) / 5,00E-02 / not available / not available / mg/kg product / 6,7
fish (EQOfish) / 5,00E-02 / 6,00E-01 / not available / mg/kg product / 6,7
nuts & seeds (EQOnuts) / 5,00E-02 / 3,00E-02 / not available / mg/kg product / 6,7
sweets (EQOsweets) / not available / not available / not available / mg/kg product / 6,7
oils & fats (EQOoils) / 5,00E-02 / 3,00E-02 / not available / mg/kg product / 6,7
* EQOs for specific food products (e.g. beans) were converted into concentration data for the corresponding food categories (e.g. vegetables) using the relative amount of the product in the food category derived from the food consumption survey (Hulshof et al. 1998); Sources: 1 = FAO/WHO 1998; 2 = JECFA 1989; 3 = Janssen et al. 1995; 4 = VROM 1997; 5 = Van Dijk-Looijaard 1993; 6 = Staatscourant 1984; 7 = Staatscourant 1993
Food intake
Food intake is variable and uncertain. Interindividual variability is assumed to follow a lognormal distribution. This choice was confirmed by fitting this distribution type to the raw dataand performing a Kolmogorov-Smirnov goodness-of-fit test.The parameters of the lognormalvariability distribution are given below. The uncertainty in these parametersis defined by the number of individuals that consumed the product (n), whichis therefore also given below. Data originates from Hulshof et al. (1998).
Food categorySymbolUnitMeanaVariancea,bn1cn2d
Drinking waterIodwl/kgbwday9.800.1845 5889
PotatoesIopotatomg/kgbwday7.900.182629 2325
VegetablesIoveg“7.700.231845 3669
FruitIofruit“7.840.34295911
CerealsIocereal“8.040.1789 5845
MeatIomeat“7.460.141059 4664
EggsIoeggs“6.360.402364 508
Milk & MilkproductsIomilk“8.530.61511 5204
CheeseIocheese“6.320.241758 2755
FishIofish“7.360.33810 95
Nuts & SeedsIonuts“6.630.612134 1317
Sweets Iosweets“6.340.57870 4455
Oils & FatsIooil“6.460.294145425
aIn the lognormal domain (natural logarithm)
b The uncertain standard deviation was restricted to values between 0 and 10
cNumber of individuals that consumed the product on one day
dNumber of individuals that consumed the product both days
Food consumption frequencies
Food consumption frequencies are variable and uncertain. They are described by beta distributions. This choice is based on literature (Slob and Bakker 2004, Slob 2006). Parametersfor each food category are given below.
Food categoryp0p2SD of SD of
Potatoes0.16580.39427.97010.710.0610.085
Vegetables0.07070.62125.9164.0660.0330.024
Meat0.03740.78623.5661.2320.0150.006
Eggs0.51590.086011.95446.6770.2731.075
Milk & Milkproducts0.03810.87681.2380.2230.0040.001
Cheese0.23560.47051.0171.1140.0020.003
Fish0.84350.01680.6517.9160.0040.049
Nuts & Seeds0.42400.21991.1512.7720.0030.008
Sweets 0.10680.74620.8110.3240.0020.001
Oils & Fats0.01740.91362.2240.2840.0100.001
Soil intake
The intake of soil particles (Isoil) in mg/day is variable as well as uncertain.The parameters of the lognormal variability distribution are given below. Theuncertainty distribution depends on the number of individuals (n), which istherefore also given in the table below. Data is obtained from Table 3 in Stanek
et al. (1998).
ParametersAge groups (years)
0 – 11 – 6 6 – 1212 – 75
n64 646464
Meana2.0192.5301.1440.227
Standard deviationa,b0.5820.5820.5820.582
a In the lognormal domain (natural logarithm)
b The uncertain standard deviation was restricted to values between 0 and 10
Intake of swimming water
The intake of swimming water is calculated using 2 parameters: (1) the water intake per time unit while swimming and (2)the time spent swimming. Values for bothparameters are given below (US-EPA 1997a; Kim & Weisel 1998).The intake of swimming water per time unit is uncertain as well as variable and follows a lognormal distribution, assumed on the basis of expert judgement. The time spent swimming is relatively easy to measure and an extensive database is available Therefore, it is assumed that this parameter is variable only. On basis of the raw data a lognormal distribution is chosen to describe the variability.
Parameter UnitsAge groups (years)
1 – 5 5 – 12 12 – 18 18 – 65 65 – 75
Intake of wateraml/min
Meanb-0.478 -0.478 -0.478-0.478 -0.478
Varianceb,c0.380 0.380 0.380 0.380 0.380
Time spent swimmingdmin/day
Meanb0.608 0.859 0.817 0.321 0.342
Varianceb0.527 0.335 0.367 0.545 0.446
a The lognormal intake distribution was restricted to values below 200 ml/min.
bIn the lognormal domain (natural logarithm)
c The uncertain standard deviation was restricted to values between 0 and 10
c The lognormal time distribution was restricted to values below 720 min/day
Bodyweight
Bodyweight, in kg, is variable only and follows a lognormal distribution. Data originates from CBS (1999).
BodyweightAge groups (years)
0-1 1-2 2-3 3-4 4-5 5-6 6-7 7-8 8-99-10 10-11
Mean 7.73 11.65 14.06 16.37 18.76 21.27 24.11 27.12 30.3833.82 37.45
SD 1.45 2.20 2.70 3.28 3.95 4.74 5.73 6.80 8.169.59 11.21
Age groups (years)
11-12 12-13 13-14 14-15 15-16 16-17 17-18 18-1919-20 20-30 30-40 40-50 50-60
41.77 46.93 52.31 57.27 61.40 64.47 66.66 68.2769.54 71.93 74.10 75.05 75.75
12.88 14.39 15.34 15.81 16.08 16.13 16.29 16.3216.31 11.16 12.14 15.76 13.69
Age groups (years)
60-70 70-75
75.25 72.22
11.50 9.90
Reclassification of food categories
NORMTOXOriginal food categories (Hulshof et al. 1998)
Drinking water (Nalcdrw/Nalctotal)· Non alcoholic drinks + (Alcdrw/Alctotal)· Alcoholic drinks + Soupsa
PotatoesPotatoes + Potato part of the Mixed meals
Vegetables Vegetables + Legumes + Vegetable and Legume partof the Mixed meals
Fruit(Nalcfruit/Nalctotal)· Non alcoholic drinks + (Alcfruit/Alctotal· Alcoholic drinksa
Cereals Bread + Cakes & Cookies + Cereals & Thickenings + Cereal part of the Mixed meals
Meat Meat, Meat products & Poultry + Meat part of the Mixed meals
EggsEggs
Milk & Milk productsMilk & Milk products
CheeseCheese
FishFish + Fish part of the Mixed meals
Nuts & SeedsNuts, Seeds & Snacks
SweetsSugar, Candy, Sweet sandwich fillings & Sweet sauces
Oils & FatsFats, Oils & Savoury sauces + Oils & Fats part of the Mixed meals
a Nalcdrw = Intake of water based non alcoholic drinks, Nalctotal = Total intake of non
alcoholic drinks, Alcdrw = Intake of water based alcoholic drinks, Alctotal = Total intake of
alcoholic drinks
b Nalcfruit = Intake of fruit based non alcoholic drinks, Alcfruit = Intake of fruit based
alcoholic drinks
The beta distribution
The consumption frequency of food products can, according to Slob & Bakker (2004), be described by a beta distribution. The beta distribution has four input variables: a minimum, maximum and two shape parameters; α and β. Because the distribution describes a fraction, all values have to be between 0 and 1, which are therefore the minimum and maximum value. and can be obtained from the consumption frequencies of the surveyed population. In the 2 days VCP-3, there are three possibilities for the consumption frequency:
- p0, when an individual consumed not at all
- p1, when an individual consumed one of the days
- p2, when an individual consumed both days
Given that p is generated by the beta distribution, the probabilities for p0, p1 and p2 are:
The mean and variance of the beta distribution are given by Equations 1 and 2 (Abramowitz and Stegun 1965).
(1)
(2)
Substitution of p and p2 in the expressions for the consumption frequencies with equations in terms of and , results (after rewriting) in equations for and in terms of consumption frequencies (Equation 3 and 4).
(3)
(4)
The beta distribution is used to calculate the consumption frequency as a life long average. Because the data reflects the consumption frequencies of different age groups weighted values have to be taken into account. The weight of each data point can be obtained by Equation 5.
(5)
In which wj is the weight of the data of individual j, ai is the number of years in age group i, where i representsthe age group of individual j, ni is the fraction of individuals in age group i (CBS 1999) and life is the life expectance of the population of interest.
Uncertainty in the parameters of the beta distribution
To estimate the uncertainty in the and , a covariance structure for hasto be obtained. This covariance structure gives the variances of and on thediagonal. The consumption frequency of each individual can be either p0, p1 orp2. In another notation consumption frequencies are given by:
yj=(1,0) if the jth individual gives data (0,0)
yj=(0,0) if the jth individual gives data (1,0) or (0,1)
yj=(0,1) if the jth individual gives data (1,1)
The parameters (p0, p2) can be estimated by Equation6.
(6)
The covariance structure of this estimate is given by Equation A.7.
(7)
The so called Delta method (Rao, 1965) tells us that the covariance structureof and can be obtained by Equation 8.
(8)
1 and 2 are the equations for and which are given by Equations 3 and4 respectively.D stands for the Jacobian matrix which contains the partial differentialequations of 1 and 2 to p1 and p2, according to:
Using this matrix, Equation 8 results in the covariance structure for and, from which the variance in those parameters can be obtained.
References
Abramowitz M, Stegun IA. Handbook of mathematical functions with formulas, graphs, and mathematical tables. Dover publications, New York, 1965.
CBS. Vademecum Gezondheidsstatistiek Nederland 1999. Centraal Bureau voor de Statistiek,Ministerie van Volksgezondheid, Welzijn en Sport, Voorburg/Heerlen, The Netherlands (in Dutch),1999.
FAO/WHO. Inventory of IPCS and other WHO pesticide evaluations and summary of toxicological evaluations performed by the Joint Meeting on Pesticide Residues (JMPR) through 1998.Geneva, Switzerland, 1998.
Hulshof KFAM, Kistemaker C, Bouman M. De consumptie van groepen voedingsmiddelen door Nederlandse bevolkingsgroepen, Voedselconsumptiepeiling 1997-1998. TNO-report v98.804, Netherlands Organisation for Applied Scientific Research TNO, Zeist, The Netherlands (in Dutch), 1998.
Janssen PJCM, Apeldoorn van ME, Koten-Vermeulen van JEM, Mennes WC. Human-toxicological criteria for serious soil contamination: compounds evaluated in 1993 and 1994. Report nr. 715810009, National Institute of Public Health and the Environment, Bilthoven, The Netherlands, 1995.
JECFA. Toxicological evaluation of certain food additives, twenty-sixth report of the joint FAO/WHO expert committee on food additives. International program on chemical safety, FAO/WHO, Food Additives Series 24. Geneva, Switzerland, 1989.
Kim H, Weisel CP. Dermal absorption of dichloro- and trichloroacetic acids from chlorinated water. J Expo Sci Environ Epidemiol1998; 8(4):555–575.
Rao CR. 1965. Linear statistical inference and its applications. Wiley & Sons. New York, US p. 357
Slob W. Probabilistic dietary exposure assessment taking into account variability in both amount and frequency of consumption. Food Chem Toxicol2006; 44:933–951.
Slob W, Bakker MI. Probabilistische berekening van inname van stoffen via incidenteel geconsumeerde voedingsproducten. Report 320103003/2004. National Institute of Public Health and the Environment. Bilthoven, The Netherlands (in Dutch), 2004.
Staatscourant. Beschikking residuen van bestrijdingsmiddelen. Nederlandse Staatscourant 54 (in Dutch), 1984.
Staatscourant. Warenwetregeling normen zware metalen. Nederlandse Staatscourant 40:21 (in Dutch). 1993.
Stanek EJ, Calabrese EJ, Xu L. A caution for Monte Carlo risk assessment of long term exposures based on short term exposure study data. Human and Ecological Risk Assessment 1998;4(2):409–422.
U.S. EPA.Exposure factors handbook, Volume III, Activity Factors. EPA/600/p-95/002fc. U.S. EPA, Office of Research and Development,Washington, DC, 1997.
Van Dijk-Looijaard AM. Herziening normen waterleiding besluit. Swo 93.340, KIWA, Nieuwegein, The Netherlands (in Dutch), 1993.
VROM. Integrale normstelling stoffen. Milieukwaliteitsnormen bodem, water, lucht. Netherlands ministry of housing, spatial planning and the environment,The Hage, The Netherlands (in Dutch),1997.