Maria F Poças
email: mfpocas@esb.ucp.pt

Jorge C Oliveira

Henrique J Pinto

Maria E Zacarias

Timothy Hogg

Pinto

Poças 1&4•

M F F ; Oliveira

J C ; Pinto

H J ; Zacarias

M E ; Hogg

Characterization of Patterns of Food Packaging Usage in Portuguese Homes

Keywords: prob modelling, Exposure assessment Additives/Contaminants: Food contact materials, Migration

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Introduction

Exposure, in a dietary context, is defined as the amount of a certain substance that is consumed and is usually expressed as the amount of substance per mass of consumer body weight per day [START_REF] Holmes | Dietary exposure to chemical migrants from food contact materials: a probabilistic approach[END_REF]. When applied to food contact packaging, exposure can be expressed in terms of the concentration of the substance that migrated from the material in contact and the amount of food contained in the package consumed per day (1). In order to assess the exposure to packaging chemicals, it is necessary to know what type of food (chemical and physical nature) is packaged in what type of material, as this determines the presence and concentration of the chemical and influences the potential for migration into the type of food [START_REF] Poças | Exposure assessment of chemicals from packaging materials in foods: a review[END_REF].

=

(1)

The concentration data (C) may be obtained by analysing real food/packaging systems collected from the market (monitoring real food systems) or through migration experiments carried out under controlled conditions of time and temperature of contact between the materials and a food simulant instead of the food itself. Mathematical models may also be used to estimate migration data [START_REF] Poças | A Critical Survey of Predictive Mathematical Models for Migration from Packaging[END_REF].

The food consumption term (FW) represents the amount of food eaten that was in contact with a packaging material from which migration occurred. Therefore, this term is linked to the packaging usage -the amount of packaging used to pack the food that the consumer eats. Packaging usage data are very scarce and most consumption surveys have been designed to gather information on the food, regardless of their packaging systems. Thus, adequate information of packaging usage, usable to assess exposure to migrants from packaging, is not readily available.

Data on almost all aspects of food packaging in Portugal are virtually nonexistent. A report with market data collected through statistics of national and trade associations and through interviews to major food companies and packaging suppliers was published in 1995 [START_REF] Poças | Portugal Food Packaging Trends and Market[END_REF]. However, this report lacks obvious updating, as well as the detail required for this specific purpose. The Euromonitor Report provides data The methods for estimating consumer exposure can and should follow a hierarchical, stepwise approach, proceeding from the level of more conservative assumptions and lower accuracy, often corresponding to point estimates, to the more refined probabilistic approaches. When the less exact, first level, results do not rule out the possibility of non-compliance with the relevant food safety objective, then more refined approaches are required. Different levels of refinement may be achieved depending on the type and quality of data available for each term of equation ( 1) and the scenarios behind. An approach between the simplified point estimates based on worst-case assumptions for both the concentration and food intake terms of the exposure equation and the elaborated probabilistic approaches considering variability and uncertainty of the inputs in the exposure equation, may consist in the adoption of a similar approach to the one followed by the official agencies of the US [START_REF] Poças | Exposure assessment of chemicals from packaging materials in foods: a review[END_REF]. The FDA defines a consumption factor (CF) that describes the fraction of the daily diet expected to contact specific packaging materials and a food-type factor (FTF) that accounts for the variable nature of food contacting each type of packaging material (USFDA, 2007). This corresponds to a more refined first-step approach when compared to that applied in the EU. The application of this approach here would require the development of a framework, bringing together CF and FTF derived and adapted to the European consumption patterns of packaged food. An application of this FDA concept to the exposure of Irish children to packaging migrants was reported by [START_REF] Duffy | Estimation of exposure to food packaging materials. 3: Development of consumption factors and food-type distribution factors from data collected on Irish Children[END_REF].

The focus of this paper is on the use of consumption and food-type factors derived from data collected at consumer level. The data collected allow for a probabilistic approach as an example provided, and was collected in the scope of a national funded research project MIGRAMODEL. One of the objectives of the project was the development of a framework for exposure assessment of packaging migrants. The project focused on the collection of updated and more complete data on packaging usage enabling the refinement and possible correction of current EU assumptions to exposure estimations and to assist on prioritization of market surveillances. The data include packaging usage data collected at consumer level complemented by data

Materials and Methods

The collection of data within the project scope was performed in three trials that took place during 2007 and 2008: the first during 1-week period from a sample of consumers connected to the project; the second during 1-week period from a sample of consumers participants in a scheme of door-to-door collection of packaging waste in Porto city; and the third during a 1-month period from a second sample of consumers connected to the project. The data from this latter trial were used in the work presented here. Packages used domestically by the consumer sample were collected during 30 subsequent days and analyzed in the laboratory. This collection period was selected because in previous work a one-week period proved to be insufficient.

The elements of the consumer sample were members of MIGRAMODEL project team, relatives and faculty members. The sample was composed of 34 households, accounting for a total of 105 persons. Separate collection of those packages used by children under 12 years only was requested. The household was characterized through a short questionnaire, considering: number of persons, weight, age and gender of each household member and level of household annual income. The household member responsible for package collection was instructed by the project team as to which packages and food contact materials should be considered. Consumers tend to disregard items such as wrapping film, bread or fruit bags as packaging. Persons were encouraged to include any item in the case of doubt. A leaflet with pictures of examples was distributed and a phone contact with the project team was available during the collection period.

The packaging materials and systems used (consumed) by each household were brought into the laboratory and analyzed for the characteristics bellow described. A total of 6 297 packaging items were handled.

Type of package: each package or material was classified as bottle, jar, can, cup/lid, tray/lid, tray/wrap, flexible, liquid carton, box, and folding carton. Packaging material: the packaging materials were segmented as: glass, tinplate, aluminium, all-plastic multilayer, multilayer (multi-material), paper, coated paper (wax or PE coating), carton board and plastics. The latter were further segmented into different major types of plastics: PET, PP, HDPE, LDPE, PS. Material identification was, in most cases, based on previous knowledge and experience and confirmation, when required, was done by DSC.

Closures for glass packages were not accounted for. Nevertheless, their amount can be estimated from data on the type of package. The data on polymeric coatings of tinplate and aluminium packages are associated to the data on these metal packages, not to the plastic class. All-plastic multilayer included laminates used mainly in flexible packaging and lids of rigid packages, made exclusively from several plastic layers.

Multilayer group of materials, included liquid cartons (board, plastic and aluminium; board and plastic) and flexible packaging composed of plastic, paper and metal or metalized film. The differentiation between the major plastics was performed taking into consideration the major plastic component of the package. Polyethylene was divided into two major groups only, corresponding to high and low densities. No other differentiation between different grades of a plastic was performed.

Packages characteristics:

-Geometry -the packages were classified according to their general geometry as rectangular, cylindrical, pyramid truncated, cone truncated, sphere or flexible for non rigid packages;

-Capacity -the nominal amount of food product according to the labelling information was recorded; when it was not possible to know the amount of food contained/in contact with the material, the surface area was determined and the EU conventional ratio between the surface area of the package and amount of food -6 dm 2 /kg -was assumed;

-The weight and surface area in contact with food of package was measured and ratio package surface area/mass of food was calculated for all packaging items handled in the laboratory; All materials considered were in direct contact with the food products, except carton board, which was in all samples, a non-direct contact material. However, because migration can also occur from non-direct contact materials, carton board was also considered in the consumption factors estimation.

Food items were grouped according to the list presented in Table 1. The list was based on the list prepared under the scope of the European FACET project [START_REF] Oldring | Exposure to substances from food contact materials and an introduction to the FACET project[END_REF]. This list is still in draft form and a simplified version of it was used here. The authors of the present article employed a compatible coding of food-types in order to allow for future integration if so desired.

Each food item was assigned into a food type, corresponding to food simulants, according to European food contact legislation (Council Directive 85/572/EEC and Commission Directive 2007/19/CE): A -water, B -3% acid solution, C -10% ethanolic solution, D -olive oil, E -50% ethanolic solution to mimic milk and some other dairy foods. In the case of food items requiring more than one testing simulant, the fattier simulant one was considered. A "None" was assigned for the cases in contact with dry, solid, non-fatty foods, like bread or flour.

The data were used to estimate:

-The global amount of used packaging material: this was calculated as the sum, for all food items, of the package surface area and weight. The total amount (all materials together in kg) were averaged by the 30 days period and by the total number of persons ( 2 (3)

-The amount of food weight of each household, per body weight of the household, was calculated as above but using the FW mj in equation ( 3);

-The ratio -package surface area/mass of food for each type (4) of packaging material (distribution of values):

[ ] [ ] [ ] m ij m ij m FW S FW S = / , dm 2 /kg (4)
-The estimates of consumption factors (CF) that represent the fraction of the daily diet expected to contact specific packaging materials (USFDA, 2007) was calculated as indicated in equation ( 5):

- ∑∑∑ ∑∑       = m i j mij m i j ij m FW FW CF (5)
-The estimates of food type factors (FTF) that reflect the fraction of all food contacting each material m which nature is according to the types t of foods: aqueous, acidic, alcoholic, fatty, dairy or dry (6). This corresponds to an adaptation of the USFDA approach to the simulants foreseen in the European legislation.

m t i j tij tm i j ij tm FW FW FDF             = ∑∑∑ ∑∑ (6)
Food eaten out of the home was not accounted for in this analysis, which obviously contributes to underestimation of the absolute values for consumption.

Example of an exposure calculation

The exposure of the Portuguese consumer to 2-aminobenzamide (2-ABA; CAS 88-68-6) was estimated using the data gathered in this study. 2-ABA may be used as a scavenger for acetaldehyde in PET bottles. In European legislation it is authorised for PET for water and beverages with a SML=0.05 mg/kg food (Commission Directive 2002/72/CE). USFDA limit the use of 2-ABA subject to the restriction of levels in the finished container not to exceed 500 mg/kg in bottles intended for water and levels not to exceed 250 mg/kg in bottles intended for non-water, aqueous, acidic and low-alcohol food applications. Information from the safety evaluation [START_REF] Scf | Opinion of the Scientific Committee on Food on the 21st additional list of monomers and additives for food contact materials[END_REF] indicates that the migration of 2-ABA from PET bottles containing 500 mg/kg of the substance to water, 3% acetic acid, and 10% ethanol was found to be maximum 0.04 mg/kg food in 10% ethanol after 30 days at 40ºC. For the exposure calculation examples a single estimate of the concentration of 2-ABA was set at the SML value. The exposure is estimated under the conditions foreseen by different scenarios: i) USFDA, ii) European conventional assumptions, iii) using the CF and FTF derived in the present work and iv) using a partially probabilistic approach by combining the single-point estimate for the concentration as above described but considering the whole distribution of values found for the food intake per kg bw in the sample of consumers. The software Crystal Ball 7.2.2. (Decisioneering, Inc.) was used to fit the probability distributions to the values of the food intake FW (in kg food /kg bw .day) and to perform the probabilistic simulation.

Monte Carlo was used as sampling method with 10 000 trials for each run.

Results and discussion

Characterization of the consumer sample

The data collected through the questionnaire were used to characterise the consumer sample. Average results for bodyweight and age are presented in Table 2. Results for the children are presented separately. Figures 1 and2 respectively, and a lower percentage of elderly people, 4% whereas the national average is 17%. The differences in terms of distribution by gender are not relevant with values around 50% of each gender in both cases.

Global amount of food consumed and packaging material used

The average amount of food consumed at home and the packaging materials used by adults and children together and by children alone, are presented in Table 3. The average value for daily intake of packaged food of all consumers is close to the value assumed for the EU (1 kg/day.person) for the assessment of safety of substances intended to be used in the production of plastics packages. The value found for the average daily intake when expressed per kg body weight is the same as the value typically assumed: 17g/kg bw [START_REF] Efsa | Food contact materials note for guidance[END_REF]. However, these values are most probably underestimated because the packaged food consumed out of the home was not accounted for, as explained above. Figure 3 presents the distribution of values found that range from 5 to more than 35 g/kg bw . The types of food according to the simulants foreseen in the EU, accounted as the percents of food taken at home are: 18% aqueous, 10% acidic, 5% ethanolic, 25% milky and 14% fatty.

The values found for the children's sample only are considerably lower than the results found for Irish children between 5 and 12 years old. [START_REF] Duffy | Estimation of exposure to food packaging materials. 2: Patterns of intakes of packaged food in Irish Children aged 5-12 years[END_REF] estimated a mean daily consumption of packaged food, by these children, of 1.2 kg/day, corresponding to 39 g/kg bw , compared to the 21 g/kg bw found in this study for Portuguese children. The value found in this study for food intake per child -0.483 kg food /day.child -is also low when compared to the value found for British children -0.823 kg food /day.child [START_REF] Fsa | Measurement of packaged food intake by children, by kilogram body weight, to include type of packaging and foodstuff[END_REF]. The way of data gathering followed in this study, does not account for the fact that in each household some of the packages items collected are in fact shared by both adults and children although ending on the adult bin, thus contributing to lowering the values found for children. The value found in this study for the whole sample data (0.947 kg food /day.person) is higher than for the children, as was to be expected. weight. The results obtained in this study confirm the values previously found in a oneweek study, and show values ranging from lower than 0.1 dm 2 /day.kg bw , which corresponds to the value assumed in European legislation, to values around 0.6 dm 2 /day.kg bw , a much higher value. The average value is 0.2 dm 2 /day.kg bw (standard deviation = 0.11 dm 2 /day.kg bw ). This value is lower than the European average value estimated by ILSI of 20.1 dm 2 /person/day that corresponds to 0.34 dm 2 /day.kg bw [START_REF] Brown | Food consumption and packaging usage factors[END_REF]. ILSI estimates indicated a value of 12.4 dm 2 /person/day for plastics that compare to the value found in this study -8 dm 2 /person/day.

Ratio -packaging surface area per amount of food in contact

The ratio of packaging surface area to the amount of food in contact (S/FW) was calculated for each material (Table 4). Packages made from glass and tin plate present average ratios around 10 dm 2 /kg food and relatively low standard deviation. This could be expected because the range of formats and shapes in these packages do not vary as much as in the case of other materials. In the aluminium group are included rigid cans for foods and beverages, semi-rigid shallow trays and wrapping foil. This variation in the formats, shapes and sizes originates a higher average and spreader ratios. A large proportion of PET is used in beverage packaging and in capacities as large as 5 L. Trays for confectionery and cakes, products with low density, contribute to the higher range of the distribution of values for the ratio S/FW found for PET. These light products, including bread, are major applications for flexible PP, thus yielding high values of ratio S/FW. PP secondary packaging and paper for tea bags present values around 600 dm 2 /kg food . PS entries in the data base include cups for solid yogurts and other dairy products, cakes and baked products as well, and trays for meat, fresh cheese and some fruits. Average ratio values of S/FW=12.6 dm 2 /kg food (σ=7.3) were found. Liquid cartons (aseptic and non-aseptic) are included in the group of materials referred to as Multilayer. The S/FW of milk and juice liquid cartons ranges from 5.75 dm 2 /kg food for packages of 1.5L to ca. 13 dm 2 /kg food for smaller packages of 0.2L. Although many other types of flexible packages, made from metalized materials and combinations of paper, aluminium foil and plastic, are included in this group, liquid cartons account for 94% of total package surface area and 97% of the food weight of this group. Paper is the material presenting the highest values of S/FW due to its use for dry, powder and light in weight products. Figure 5a These results emphasize conclusions drawn before by other authors that the assumption that packages geometry may be described, for safety assessments, as a cube of surface area 6 dm 2 , containing 1 kg of food, is inappropriate today, because globally packages sizes tend to decrease which leads to an increase in contacting surface area per kg of food [START_REF] Dionisi | Estimates of per capita exposure to substances migrating from canned foods and beverages[END_REF][START_REF] Grob | European legal limits for migration from food packaging materials: 1. Food should prevail over simulants; 2.More realistic conversion from concentrations to limits per surface area. PVC cling films in contact with cheese as an example[END_REF][START_REF] Poças | Exposure assessment of chemicals from packaging materials in foods: a review[END_REF]. In a similar study performed in The Netherlands values for the S/FW ratio varying from 6 to 95 dm 2 /kg food were found [START_REF] Bouma | Domestic use of food packaging materials in the Netherlands[END_REF].

Estimates of consumption factors (CF)

CF represent the ratio of the weight of all food contacting a specific packaging material to the weight of all food packaged consumed. CF was calculated with equation ( 5), according to the procedure followed by FDA [START_REF] Cassidy | USFDA's revised consumption factor for polystyrene used in food-contact applications[END_REF]. of the food intake, but this material is almost not found in the case of children's consumption. Plastics all together account for more than 50% of the daily diet. PET accounts for 26% of the food (mostly drinks). The remaining plastics split among themselves ca 33% of the food. The plastic PS has a higher relative importance (10%) in children's diet, as compared to the importance when adults are also considered ( 4%). This may be explained by the expected higher consumption of dairy products by children and the fact that these products are typically packaged in PS packages in Portugal.

The percentages of the food consumed contacting specific materials are compared to the USFDA CF in Table 5. In order to allow a comparison between the results of this study and the USFDA CF, some grouping of the classes of materials was made: consumption factors of aluminium and tinplate in this study were added together and compared to the sum of the factors for metal coated and metal uncoated in FDA; plastics and all-plastics uncoated paper and carton board were compared directly. USFDA segments of adhesives, retort pouch and microwave susceptors were not considered. The comparison shows a lower usage of glass and metal in Portugal as compared to USA and a higher percentage of plastics and multimaterial. The CF of some specific plastics are also presented in Table 5. After appropriate manipulation to conversion into the same base, the values found for HDPE, LDPE and LLDPE together, and PS are very similar to the FDA values for these plastics. The value for PET, however, is very different. Results in this study show that ca 26% of the food consumed at home was packaged in PET, while the correspondent CF for USA is only 7%. Since a large proportion of the PET entries in the study database is for drinks, this difference is coherent with the lower values found for Portuguese usage of the other materials very much used for drinks -glass and metal, as a certain compensation between materials used for drinks may occur.

The results for CF obtained in this 1-month study are presented for adults and children together and for children only. The latter are compared with the results presented by [START_REF] Duffy | Estimation of exposure to food packaging materials. 3: Development of consumption factors and food-type distribution factors from data collected on Irish Children[END_REF]. Unfortunately, due to the use of a different fragmentation between the packaging materials, it is only possible to compare glass, paper and board classes.

Estimates of food type distribution factors (FTF)

The FTF for the different packaging material are presented in Table 6. The results presented indicate that:

-Glass is used 64% for alcoholic products and the remaining is distributed for the different types of products and fatty products account for 8%; -Tin plate is used in mainly 3 type of products/simulants: aqueous, acidic and fatty;

-PET, as expected, has a major application in aqueous and acidic products, related to soft drinks; -PP is apparently used in significant proportions in dry products, as well as in fatty foods;

-HDPE is primarily used in dairy products for which simulant E is defined; -Multilayer (multi-material) packages have a significant proportion of liquid cartons, used for milk and juice, as the food type factors reflect; -Carton board, is mainly used for non-contact applications thus no simulant is specified.

The results are not directly compared with the FTF from FDA since the classification of foods followed is different, according to the food simulants foreseen in Europe.

The use of the CF and FTF require the complete understanding of the classification behind the factors derived. For example: if the factors are to be used to estimate the exposure to an additive migrating from the LDPE family of films, the following must be taken in consideration:

-the percentage of daily food intake packaged in LDPE single-layer material is 5% (Table 5) from which ca 75% is for dry food and 25% is for fatty food (Table 6); -PE based films are likely to be the contact layer in the Multilayer and Plasticsmultilayer classes; the percentage of daily food intake in contact with Multilayer is 22% (Figure 6) from which 12% is acidic foods and 85% is milky food (Table 6); the percentage of daily food intake in contact with Plastics-multilayer is 6% (Figure 6) from which 54% are fatty foods, 28% are dry foods and 14% are ethanolic (BIB,s for wine); these contributions should all be accounted for.

Example of exposure calculation

The results from the exposure calculations with the different assumptions and scenarios are presented in Table 7. In all cases the concentration of the migrant is the same single value set at the maximum migration limit. The USFDA scenario yields an exposure of 4.8 µg/person.day that is 10 times lower than the scenario from EU conventional, i.e., without considering the CF and FTF -50 µg/person.day. When the CF and FTF obtained in the study are considered and combined with the food intake data for the studied sample, the value is closer to the USFDA value -11 µg/person.day.

For the probabilistic approach, all values of the consumer's food intake FW in kg food /kg bw were considered, instead of the average value only. The distribution of

Conclusions

The results achieved contribute to a refinement and possible correction of current EU assumptions for exposure assessment when applied to a particular population, in this case largely Portuguese urban families of working age, in which concerns migration of substances from the package into the food. For any particular section of the population, Portuguese consumption patterns may reasonably be expected to be similar to those in other southern European countries with globally similar dietary habits and lifestyles.

Therefore results of this pilot-study may have significance beyond the strict national scope. The data collected on consumption and food-type factors, in spite of the limitations inherent to the resources required to conduct such a study, allow for the adoption of a more realistic and more refined approach than the worst-case estimates, combining a probabilistic approach to model variables for which the distribution of values are known. The amount of packaging (in terms surface area) that the consumer uses and the food intake can be combined with migration data for a certain and specific substance that is present in the packaging material in question, and used in equation ( 1) to estimate the exposure. The major limitation may be the size of the sample.

Nevertheless the number of packaging items was similar to other studies. For example the study conducted in British children handled 6500 items [START_REF] Fsa | Measurement of packaged food intake by children, by kilogram body weight, to include type of packaging and foodstuff[END_REF]. The sampling method followed proved to be sufficient to gather data for the adults and children together, but not to consider the children only. This consumer segment should be further investigated. In any case the data framework will be complemented with analyses of data obtained from the industry sources.

F

  value) on Packaged Food in Portugal but it does not give details on the packaging systems used(Euromonitor, 2008).

  level (packaging and food associations were contacted in order to gather statistic national data).

--

  The global amount of food (in kg) consumed by the population sample was calculated as above but using the item food weight FW imj in equation (2); The packaging usage of each household i, per body weight of the household, for all materials together, was calculated as (3):

  represent the distributions of weights and ages, respectively of the whole sample population, adults and children together, which is evident from the bimodal shape of the distributions. The national statistics for population indicators was used to assess how representative the consumer sample is of the whole Portuguese population. The consumer sample used in this work was taken from the Metropolitan Porto area which represents 12% of the total population, 45% of which is classified as urban. The national average household size is 2.8 members which can be compared to the 3.1 of the present sample. The Portuguese population as a whole presents an age distribution with 15% individuals younger than 14 years and 56% in the range of 24 to 64 years old. The sample in this study had a relatively higher percent of consumers in these two ranges of age, 24 and 66%

Figure 4

 4 Figure4presents the distribution of values found for the packaging usage, in terms of surface area of all packaging materials that a consumer uses per day and per kg of body

  presents the distribution of values of S/FW when all together, and Figure5bpresents the distribution of values for the PS, as an example.

Figure 6

 6 Figure 6 and 7 represent the consumption factors for adults and children together and for children alone, respectively. A comparison between the two Figures show that multilayer materials (mostly liquid cartons) have a lower use as compared to the value found when children only is considered. In the whole sample, glass accounts for ca 6%

  together and compared to plastics from FDA; coated paper and multilayer multimaterial together were compared to coated paper values from FDA;

-

  PS finds its major application in products for which simulant E (dairy foods) and D (fatty) are assigned;

  found to be better described by a Lognormal distribution. The distribution function was truncated at the minimum and maximum values found on the study data base. The estimates for the exposure are presented in Figure 8. The distribution of estimated values is better fitted to the Weibull probability distribution function. The values range from 0.059 to 0.426 µg 2-ABA/kg bw .day. From the Figure the different percentiles can be read out if required.

Figure 1 .Figure 3 .

 13 Figure 1. Weight distribution of person in the sample 270x185mm (300 x 300 DPI)

Figure 4 .Figure 5 .Figure 6 .Figure 7 .Figure 8 .

 45678 Figure 4. Packaging (all materials) surface area the consumers are exposed to, per day and per kg of body weight. Adults and children together. 270x192mm (300 x 300 DPI)

  consumption patterns from this type of population can be best represented in exposure assessments and consequent risk assessments.

	Key words: food packaging, migration, packaging usage, exposure assessment
	Abbreviations and symbols
	A, B, C, E, D, None	Food simulants
	BIB		Bag-in-box
	BW F C CF o DSC r Body weight, kg bw Concentration of migrant in food or food simulant, mg/kg food Consumption factors Differential scanning calorimetry E Exposure mg/person.day or mg/kg bw .day
	FTF FW LDPE HDPE	Food type factors Food weight, kg food /person.day or kg food /kg bw .day P Low density polyethylene e High density polyethylene
	Max Min N		Maximum e Minimum r Number of household members
	PET PP PS PW S SML µ σ Indices		Polyethylene Terephthalate Polypropylene R Polystyrene Packaging weigh, kg e Packaging surface area of contact, dm 2 v Specific migration limit mg/kg food i Average e Standard deviation w
	i j m n t		Household Packaged food item Packaging material Member of household Type of food: aqueous, acidic, ethanolic, dairy, dry O n l
	bw		Body weight	y

Table 1 .

 1 Food groups

	o r
	P
	e
	e r
	R
	e
	v i e
	w
	O n l
	y

Table 3 .

 3 Global results averaged by day, person and by average person body weight

			Food weight, kg	Package surface area, dm 2	Package weight, kg
		Total	2 982	34 341	303
	Children plus adults	Total/day.person Total/day.kg bw	0.947 0.017	10.9 0.192	0.096 0.002
		Total/day.child	0.483	5.9	0.027
	Children only Total/day. kg bw	0.021	0.249	0.001

Table 4 .

 4 Statistics for the distribution of values of the ratio surface area/ food amount (dm 2 /Kg food ) for each packaging material.

		µ	σ	Min.	Max.
	All materials together	24.89	48.62	0.13 700.00
	Glass	9.81	4.55	4.72	70.40
	TinPlate	10.64	4.16	1.67	21.90
	Aluminium	49.98	23.60	3.81	72.00
	PET	9.97	9.35	3.20	80.00
	PP	34.32	47.66	1.00 700.00
	HDPE	15.35	12.06	3.43 105.26
	LDPE	16.56	15.58	2.33	92.11
	PS	12.60	7.26	4.17	80.00
	Plastic Multilayer	35.48	42.54	2.84 646.15
	Multilayer	13.13	42.91	2.22 646.15
	Paper	104.01 163.34	0.13 686.67
	Coated Paper	45.02	41.15	2.22 142.86

Table 5 .

 5 Comparison between estimates of consumption factors and USFDA values

		FDA	PT	PT	IE
		Adults &	Adults &	Children	Children
		Children	Children	1-12 years	5-12 years
	Glass	10	6	1	2
	Metal (coated+uncoated)	20	4	2	6
	Plastics	40	56	41	80
	PS	4 +	4	4	-
	PET	7 +	26	14	-
	HDPE	5 +	5	4	-
	L(L)DPE *	7 +	5	1	-
	Multimaterial	20	23	43	-
	Paper and board	10	12	16	13
	* LDPE and LLDPE were not distinguished
	+ PET is 16% of plastics; PS is 10% of plastics; HDPE is 13% of plastics; plastics are
	40% of diet

Table 6 .

 6 Food type distribution factors for each packaging material

	A	B	C	E	D		None
	Glass	13	14	64	0	8	1
	Tinplate	8	53	4	3	22	10
	Aluminium	1	7	9	0	80	3
	PET	73	18	0	1	5	3
	PP	4	2	0	0	19	75
	HDPE	0	5	0	47	11	37
	LDPE	1	1	0	0	25	73
	PS	1	1	0	34	50	14
	Plastics multilayer	3	0	14	1	54	28
	Multilayer	0	12	0	85	2	1
	Paper	1	0	0	0	12	88
	Coated paper	0	0	0	0	92	8
	Carton board	0	0	1	3	9	87

Table 2 .

 2 Characteristics of the consumers' sample: adults and children *

		Food Additives and Contaminants	Page 26 of 35
		Parameter	Value
		Nº of persons in sample	105
	Adults and children	Nº of homes Average weight, kg (± St.dev.)	34 56.6 ± 23.1
		Average age, years (± St.dev.)	30.2 ± 17.8
		Nº of children	20
	Children only	Average child weight, kg (± St.dev.)	23.6 ± 10.1
		Average child age, years (± St.dev.)	6.7 ± 3.4

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Table 7 .

 7 Exposure estimation of 2-ABA with origin in PET bottles packaging materials.

	Page 27 of 35		Food Additives and Contaminants
	Assumptions/ scenario	USFDA	EU conventional	PT deterministic	PT probabilistic
					LN distribution
	FW	3 kg food /person.day	1 kg food /person.day	0.95 kg food /person.day	µ=0.017 kg food /kg bw .day σ=0.008
					Min=0.005
					Max=0.036
	C 2-ABA	0.05 mg/kg food	0.05 mg/kg food	0.05 mg/kg food	0.05 mg/kg food
	BW	--	60 kg bw	57 kg bw
	FTF PET	0.01 Aqueous 0.97 Acidic	--	0.73 A 0.18 B	0.73 A 0.18 B
	CF PET	0.082 PET/Polymers 0.40 Polymers/All	--	0.26 PET/All	0.26 PET/All
					Weibull distribution
	Exposure	4.8 µg/person.day	50 µg/person.day 0.8 µg/ kg bw .day	11 µg/person.day 0.2 µg/ kg bw .day	µ=0.20 µg/kg bw .day σ=0.081 Min=0.059
					Max=0.426

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Acknowledgments

Migramodel -Mathematical modelling for exposure assessment and compliance of safety requirements (Contract number ADI/2006/V4.1/0036) -Project financed by Agência de Inovação under the Programme IDEIA TRUEFOOD -Traditional United Europe Food (Contract number: FOOD-CT-2006-016264) -Integrated Project financed by the European Commission under the 6th Framework Programme for RTD.