Intake estimates pesticides

Methyl parathion is approved only for use on crops. The maximum amount of methyl parathion residue allowed by the Food and Drug Administration (FDA) and EPA on crops used as food is 0.1-1 ppm. The FDA has monitored the food supply for pesticides for a number of years. FDA purchases many kinds of foods through Market Basket Surveys and analyzes them for residue levels of pesticides. These FDA studies allow scientists to estimate the daily intake of pesticides. Generally, the FDA monitoring studies conclude that the U.S. food supply contains only very small amounts of pesticides that are not a concern. However, there have been some reports of the illegal use of methyl parathion inside homes. For more information, see Section 1.7 and Chapter 6. 

Hamilton DJ, Holland PT, Ohlin B, et al. 1999. Optimum use of available residue data in the estimation of dietary intake of pesticides. Pestic Sci 55(2) 220-221. 

Methodology for Estimating the Dietary Intake of Pesticide Residue... 

Darnerud, P.O., Atuma, S., Aune, M., Bjerselius, R., Glynn, A., Grawe, K.P., Becker, W., 2006. Dietary intake estimations of organohalogen contaminants (dioxins, PCB, PBDE and chlorinated pesticides, e.g. DDT) based on Swedish market basket data. Food Chem. Toxicol. 44, 1597-1606. 

PSD (1999) Guidance on the estimation of dietary intakes of pesticides residues. Pesticides Safety Directorate UK. 4 November 1999. 

To date, JMPR has evaluated 240 pesticides, many of them repeatedly. JMPR establishes ADIs (based on chronic toxicity) and acute reference doses (based on acute toxicity) on the basis of the toxicological data and related information available on the substances that are being evaluated. In addition, JMPR reviews pesticide use patterns, data on the chemistry and composition of pesticides, and methods of analysis of pesticide residues. It recommends MRLs for pesticides that occur in food commodities following their use according to Good Agricultural Practice. The potential intake of pesticide residues is compared with the ADI and acute reference dose to estimate the potential dietary risks associated with the adoption of the MRLs. 

The quantity of suspended dust inhaled and the intake of pesticides adsorbed to it may be calculated rather exactly, and the intake of pesticides from deposited dust via oral pathways may at least be roughly estimated. But data supporting the amount of chemicals absorbed through dermal contact of contaminated house dust and through direct contact to contaminated surfaces are still lacking. Semivolatile pesticides like chlorpyrifos will accumulate not only in house dust but also on toys and on sorband surfaces [134]. Data from the NHEXAS of Arizona support the importance of dermal penetration of semivolatile pesticides like chlorpyrifos and diazinon as a route of residential human exposure [116]. 

The Guidelines and Criteria for the Preparation and Presentation of Complete Dossiers and Summary Dossiers for the inclusion of Active Substances in Annex I of Directive 91/414/EEC (Article 5.3 and 8.2) (Document 1663/VI/94) require that an estimate is made regarding the theoretical intakes of pesticide residues by consumers. Consumer risk assessment is a vital part of the approval process and it is in the applicant s interest to estimate potential intakes since intake estimates can assist in assessing whether further information is required. 

Thus the ADI in mg per kg per day is an estimate of the daily pesticide dietary intake that appears to be without risk over the entire human lifetime. ADI values are estabHshed and periodically reviewed by joint committees of the Eood and Agricultural Organization (EAO) and WHO of the United Nations. 

C. Soler, K. J. James, and Y. Pico. Capabilities of Different Liquid Chromatography Tandem Mass Spectrometry Systems in Determining Pesticide Residues in Food Application to Estimate Their Daily Intake. J. Chromatogr., A1157(2007) 73-84. 

To illustrate the application of 2nd-order Monte Carlo analysis, we estimated exposure of Carolina wrens to a hypothetical pesticide in cotton fields in the southwest United States. For this case study, the pesticide is assumed to be persistent, and the goal is to estimate chronic exposure (i.e., total daily intake) at the local field scale. The input data are representative of the kinds of data available during reregistration but, for this case study, are entirely hypothetical. 

The Carolina wren is primarily an insectivorous bird (94% of diet). It is nonmi-gratory and common in the cotton belt area of the southeastern United States. This species has been frequently observed foraging in or near cotton fields. Total daily intake of the hypothetical pesticide was estimated using the equation... 

The estimation of the Actual Daily Exposure assuming a person consumes a large portion of food. If this one-day exposure exceeds the Acceptable Daily Intake, then this use of the pesticide could be denied. 

The maximum value is 217 g but since this survey is based on a sample of only four days it is unlikely that this level of consumption would be sustained over a longer period. A better estimate of high-level intake over the longer term might be the 97.5th percentile, which is 150 g. Nevertheless, for organophosphate pesticides the concern relates to possible inhibition of the cholinesterase... 

Herrera, A., Arino, A., Conchello, P., Lazaro, R., Bayarri, S., Perez-Arquillue, C., Garrido, M., Jodral, M., Pozo, R., 1996. Estimates of mean daily intakes of persistent organo-chlorine pesticides from Spanish fatty foodstuffs. Bull. Environ. Contam. Toxicol. 56, 173-177. 

Stefanelli, P., Di Muccio, A., Ferrara, F., Attard Barbini, D., Generali, T., Pelosi, P., Amendola, G., Vanni, F., Di Muccio, S., Ausili, A., 2004. Estimation of intake of organochlorine pesticides and chlorobiphenyls through edible fishes from the Italian Adriatic Sea during 1997. Food Control 15, 27-34. 

The Australian Market Basket Survey (AMBS) was set up to monitor pesticides and contaminants in food and estimate their intakes in diets of Australians (ANZFA, 1998). The first total diet survey was conducted by the NHMRC in 1970 and surveys have occurred regularly since then. Currently, it is a biennial survey organised and published by the Australia New Zealand Food Authority (ANZFA, 1998). 

From the selection of specific population groups as identified above, it was clear that the risks from being exposed to OCPs can vary for different groups of individuals in the community. In 1996 a variation of a HI of 3.3 for dieldrin for a hypothetical group of high intake seafood consumers to a small fraction for the other pesticides was estimated. Many persons... 

Pesticide Period Persons Daily intake (pg kg bw day-1) ADI (pg kg bw day-1) Hazard index Lifetime risk estimate... 

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