Theoretical daily intake

The previous assumptions can be used to calculate maximum theoretical daily intake of levamisole equivalents if a consumer ate the standard meat diet containing concentrations of levamisole at the proposed MRLs. The maximum ingested residue of the parent drug and its equivalents is 397pgday, which consists of 14pgday of parent drug and 383pgday of levamisole equivalents. The calculation is shown in Table 1. 

To determine the possible exposure level via the food, the "theoretical daily intake" (TDl) was calculated. This figure was derived by utilizing data on the rate of disappearance of the food item in Canada, provided by Statistics Canada, and determining from these data, the consumption of the crop per capita (assuming disappearance rate and consumption to be comparable). It was assumed that the total crop could have residues present at about the level of analytical sensitivity of the method of detection. Thus based on the consumption level and the maximum residue level, an estimate of exposure from each crop can be calculated. The total exposure from all crops is the TDI. 

Although the main basis for proposing MRLs is the data from supervised trials, when considering the proposals Member States calculate the theoretical maximum daily intake that could occur if the proposed MRLs were adopted,... 

This maximum legal exposure, often referred to as the Theoretical Maximum Residue Contribution, or TMRC, is compared with established toxicological criteria such as the reference dose (RfD) or Acceptable Daily Intake (ADI) which represent, after analysis of animal toxicology data and extrapolations to humans, the daily exposure that is not considered to present any appreciable level of risk. When it is determined that the TMRC exposure is below the RfD or ADI, the EPA usually considers the risks from the pesticide in question to be negligible and approves the manufacturer s petition to establish a tolerance at or slightly greater than the maximum levels identified from the manufacturer s controlled field trials (Winter, 1992a). 

In chemicals regulation, NOAELs are combined with so-called safety factors to derive acceptable or tolerable daily intakes for humans (ADI, TDI), which denote exposures that can be tolerated for a lifetime without any effect. The question is whether this claim is tenable for chemicals when exposure is to a large number of substances, all at levels around their ADI. On the basis of the available experimental evidence as well as theoretical considerations, the possibility of combination effects cannot easily be ruled out. On the other hand, this possibility cannot readily be confirmed either. To decide the issue on a sound scientific basis, knowledge about relevant exposures, in terms of the nature of active chemicals, their number, potency, and levels, is essential. 

When calculating chronic dietary exposure, the deterministic models use point values for both food consumption and residue concentration, thereby yielding a point estimate of dietary exposure. In the US, the initial chronic dietary exposure estimate is the Theoretical Maximum Residue Contribution (TMRC) and is analogous to the Theoretical Maximum Daily Intake (TMDI) used to estimate chronic dietary exposure in the EU. Both the TMRC and the TMDI are relatively conservative estimates of dietary expostire. The TMRC is calculated as the product of the mean consumption value and the US pesticide tolerance [6]. In the EU, the TMDI is calculated as the product of the mean consumption value and the Maximum Residue Limit (MRL) [7]. The objective of both calculations is essentially identical to calculate an estimate of the central tendency of the dietary exposure. Both calculated values use the central tendency dietary exposure estimate as the estimate of chronic (long-term) dietary exposure and calculate it using mean consumption data and the maximum residue permitted on the commodity. 

LAMBE J., CADBEY P., GIBNEY M., (2002), Comparison of stochastic modelling of the intakes of intentionally added flavouring substances with theoretical added maximum daily intakes (TAMDI) and maximised survey-derived daily intakes (MSDI), Food Additives and Contaminants, 19, pp 2-14. 

The daily dietary intakes of BHA and BHT have been estimated in many countries. The daily intakes of BHA and BHT in Japan in 1998 were 0.119 and 0.109 mg/d/person, which reflect 0.5% and 0.7% of the acceptable daily intake (ADI), respectively (35). The estimates of theoretical maximum daily intake (TMDl) of BHA and BHT in Brazil published in 2001 were in the range of... 

Threshold limit value (ACGIEI) Theoretical maximum daily intake Time-weighted average Time-weighted average concentration... 

Pesticide Theore- tical Intake mg/day Actual Intake mg/day2 Relationship of Actual Intake to Theoretical Intake Accept- able Daily Intake mg/day3 Relationship of ADI to Actual Intake... 

On the basis of the food basket, the EU authority (EMA/CVMP) then requires applicants for MAs to estimate the theoretical maximum daily intake (TMDI) for persons weighing 60 kg, applying the equation ... 

TMDI (Theoretical Maximum Daily Intake) will be calculated as follows TMDI=X[MRLiXFJ... 

Leclercq, C., Arcella, D., and Turrini, A. Estimates of the theoretical maximum daily intake of erythorhic acid, gaUates, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) in Italy A stepwise approach. Food Chem. Toxicol. 38,1075, 2000. 

No allowable daily intake of atrazine in the human diet has been established, although 0.0375 mg/kg BW daily has been proposed -equivalent to 2.25 mg daily for a 60-kg adult, or 1.5 mg/kg diet, based on 1.5 kg food daily. In humans, the theoretical maximum residue contribution (TRMC) - a worst case estimate of dietary exposure - is 0.77 mg daily, assuming 1.5 kg of food eaten daily this is equivalent to 0.51 mg/kg diet, or 0.013 mg/kg BW daily for a 60-kg person. Another TRMC calculation is based on 0.233 mg daily per 1.5 kg diet, equivalent to 0.156 mg/kg diet, or 0.0039 mg/kg... 

Fig. 8. Theoretic course of accumulation for the total body burden of man at steady state after beginning of exposure to MeHg. A is the body burden of MeHg, a is the daily intake of MeHg and the fraction of body burden excreted daily (Berlin et al., 1975)...

Feeding of infants with formulas represents a considerable MRPs load. N -(carboxymethyl)lysine (CML) represents a chemically-defined MRP, and widely used indicator of the Maillard reaction in foods. Theoretical daily burden of dietary CML in 6-month-old breast-fed infants represents 0.01-0.03 mg/d, while in the formula-fed children 4.614.2 mg/d". In comparison with the breast-fed children, high dietary intake of CML in formula-fed infants results in significantly higher plasma CML concentration (+46%), and... 

As calories were reduced, the more elite athletes increased their protein intake to 2.5g per pound of bodyweight daily and begin trading some complex carb calories for MCT (medium chain triglyceride) oil calories (which is a fat that can not theoretically be stored as fat). MCT oil contains 8.5-9 calories per gram. 

When 7-day diet composites were collected during the four seasons of the year, Patterson et al. (37) found a mean intake of 3.0 mg Mn/day and a nutrient density of 1.6 mg Mn/1000 kcal. Based on this figure, a consumption of 1560 kcal would be adequate to meet the lower limit of the suggested safe and adequate range (63). However, in Fig. 1 the theoretical point of equilibrium is 3.55 mg and it appears that approximately 5 mg is needed to consistently maintain positive balance. These would require a daily consumption of 2250 and 3125 Kcal, respectively. Thus, it seems plausible that some individuals may be at risk for being in negative manganese balance. 

The dietary exposure is estimated as outlined in the EU Guidance Document SANCO 4145/2000 [1]. The estimated exposure is computed by multiplying the food intake of a focal species and the concentration of a particular compound in the diet. Several factors (PT, PD, see below) can be included into the calculation to model the theoretical exposure in a more realistic way. Exposure will be expressed as daily dose for all time scales based on the following equation ... 

The typical daily dietary AE intake is 10 to 100 mg (Campbell et al., 1957), although absorption is normally minimal. This quantity of dietary AE is more than enough to account for the entire increase of brain AE observed in patients with dialysis dementia. Among 22 such patients, the mean brain AE content was 22 mg/kg dry weight. The normal human brain weighs about 1500 gm and is about 80% water, or 300 gm dry weight. Thus, the total increase in AE content for the whole brain is less than 7 mg in patients with dialysis dementia. Therefore, the entire increase of brain AE in such patients can theoretically be accounted for by dietary aluminum. The increase in body aluminum stores may also be, in part, the result of AE contamination from other sources, such as Al" in dialysate water, dialysis system aluminum pipes, or aluminum leaked from anodes. 

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