Assessment of dietary exposure

The Committee estimated potential exposure on the basis of the residual concentrations of chlorite and chlorate, as reported in the submitted data for raw products of three food categories (meat and meat products, including poultry fish and fish products and fruits and vegetables) that had been treated with ASC solution. The treatment was at the proposed use level of 1200 mg sodium chlorite/ I and under optimum conditions to fulfil the technological purpose (with sufficient time of spray or immersion and drip with water wash and holding time). The available data showed that residues of chlorite and chlorate in most foods treated with ASC declined to levels below the limits of detection with time (after treatment, rinsing and a holding period). 

The occurrence data used in the calculation of dietary exposure estimates were as follows for meat and meat products, 0.1 mg/kg for both chlorite and chlorate for seafood and freshwater fish, 0.01 mg chlorite/kg and 0.1 mg chlorate/ kg for fruits and vegetables, 0.01 mg chlorite/kg for all fruits and vegetables except for leafy vegetables (0.23 mg chlorite/kg) and 0.01 mg chlorate/kg. 

The Committee noted that the estimates were highly conservative, as it was assumed that all the treated foods would be consumed daily over a lifetime and that all treated foods consumed contain the maximum residual levels of chlorite and 

1 Assessmen t of per capita dietary exposure based on data from food balance 

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One common objective of an LSMBS is to refine the estimates of actual exposure of consumers to ingredients or impurities in one or more products. For example, study results might be intended to determine a realistic human dietary exposure to pesticide residues in fresh fruits and vegetables. The advent of the Food Quality Protection Act of 1996 (FQPA) has produced an enhanced focus on the exposure of children to pesticides. A well-designed and implemented LSMBS would afford the opportunity to delineate better the exposure and risk to children and other population subgroups. The LSMBS would provide consumer-level data at or near the point of consumption, allowing the refined, relevant, and realistic assessments of dietary exposure. 

Buckland, S., Scobie, S., Hannah, M., Heslop, V., 1998b. Concentrations of PCDDs, PCDFs and PCBs in New Zealand retail foods and an assessment of dietary exposure. Organohalo. Compd. 38, 71-74. 

Muntean, N., etd. Assessment of Dietary Exposure to Some Persistent Organic Pollutants in the Republic of Karakalpakistan of Uzbekistan, Environmental Health Perspectives, iii 10(2003)... 

DG HCP, Assessment of dietary exposure to organotin compounds of the population of the EU member states. DG Health and Consumer Protection SCF/CS/CNTM/TBTC. 2003. 

Chan HM, Kim C, Khoday K, Receveue O and Kuhnlein HV (1995) Assessment of dietary exposure to trace metals in Baffin Inuitfood. Environ Health Perspect 103 740-746. 

The results of the project of National Institute of Public Health, Prague, The Health Risk Assessment of Dietary Exposures to the Selected Chemical Substances (Total Diet Study), Czech Republic, 1994 are presented in Table 14 (National Institute of Public Health in Prague, 1995b). In this study 552 composite food samples were analyzed representing 1920 individual commodities from 12 sites of the Czech Republic. No statistically significant difference was found between individual sites with a different environmental pollution level. The estimated exposure dose for the Czech Republic ranges between 28 and 41% of the PTWI. 

National Institute of Publie Health in Prague, 1995b. The Health Risk Assessment of Dietary Exposures to the Selected Chemical Substances in the Czech Republic. Prague. 

For the assessment of dietary exposure, the authors used the full distribution of the contamination for all commodities combined with the frequencies and amounts consumed and estimated an average dietary exposure below 5 ng/kg bw and high percentiles of exposure below 15 ng/kg bw. Because of the methodological choice of a probabilistic exposure assessment, cut-off points on the right of the distribution curve to simulate enforced MLs have an impact on dietary exposure when the cut-off points are located in the tail (e.g. at the level of 5 pg/kg). On the contrary, a cut-off point at a level above most of the observed values of contamination (e.g. 20 pg/kg) is ineffective. 

Gilbert, J., Brereton, P. MacDonald, S. (2001) Assessment of dietary exposure to ochratoxin A in the UK using duplicate diet approach and analysis of urine and plasma samples. Food Addit. Contam. 18, 1008-1093. 

On the assessment of dietary exposure to PFC, it is worth noting again that there are some limitations. First, a conservative estimation of PFC s dietary exposure is used because the analyzed food represents only a portion of the average diet and the dietary habits for the different groups of populatimis are not cmisidered. Second, most studies do not consider precursor compounds that could be taken up and converted to PFOS or PFOA within the human body. Factors contributing to these limitations will be addressed in future studies. 

Bemrah, N., J. C. Leblanc, and J. L. Volatier. 2008. Assessment of dietary exposure in the French population to 13 selected food colours, preservatives, antioxidants, stabilizers, emulsifiers and sweeteners. Food Addit. Contam. Part B Surveill. 1(1) 2-14. 

Bemrah, N., K. Vin, V. Sirot et al. 2012. Assessment of dietary exposure to annatto (E160b), nitrites (E249-250), sulphites (E220-228) and tartaric acid (E334) in the French population The second French total diet study. Food Addit. Contam. Fart A 29(6) 875-885. 

EFSA. 2011. Overview of the procedures currently used at EFSA for the assessment of dietary exposure to different chemical substances. EFSA J. 9 2490-2522. 

Rasmussen LG, Winning H, Savorani F, Ritz C, Engelsen SB, Astrup A, et al. Assessment of dietary exposure related to dietary G1 and fibre intake in a nutritional metabolomic study of human urine. Genes Nutr 2012 7 281-93. 

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