Tolerance reassessment

The Act established the Tolerance Reassessment Advisory Committee (TRAC), composed of individuals with a variety of backgrounds and interests to consult and make recommendations to both the EPA and USDA. When this committee went out of existence in 1999, the EPA and USDA established a new advisory committee, the Committee to Advise on Reassessment and Transition (CARAT) to provide strategic advice on issues raised by this Act. 

USEPA (2006a). Memorandum. Atrazine Finalization of Interim Reregistration Eligibility Decision and Completion of Tolerance Reassessment and Reregistration Eligibility Process. 

Reevaluation of tolerances EPA establishes a tolerance reassessment program and lays out a schedule to reevaluate all tolerances that were in place as of August, 1996, within 10 years. 

The importance of U.S. tolerances stems from both the stringency of the scientific evaluation process upon which they are based and the important role of the U.S. in international food trade. Some countries actually defer to U.S. tolerances in lieu of their own legislation for export purposes (e.g., Costa Rica, Mexico). It is expected that U.S. tolerances will be highly influential in future development of MRL policy within the NAFTA countries, particularly as regional harmonization efforts may some day lead to a system of NAFTA MRLs. The FQPA-mandated tolerance reassessment process has resulted in many changes in U.S. tolerances, particularly the loss or reduction of tolerances for some older products, and these changes have the potential to impact use and food export practices in U.S. trading partners. 

Example 31 In Table 2.5, the term under the root would increase from 0.264 to 1.264 this increase by a factor of 4.8 translates into CI( y) being 2.2 times larger than CI(T). The corresponding test at x = 125 (0.517 < y(x) < 0.547) shows the measured value in Table 2.2 (0.537) to be well within the tolerated limits. Only if the residual standard deviation (0.00363) was much larger than expected for the analytical method would there be reason to reassess this calculation. 

Propofol 5-20 mcg/kg/min continuous IV infusion (in patients who require frequent neurological assessment) Reassess goals daily and titrate/taper dose to desired response (as patients may accumulate the medication or become tolerant)... 

The efficacy of polysaccharide vaccine in preventing invasive pnenmococcal disease, pnenmonia, and death has been assessed in a donble-blind, randomized, placebo-controlled trial in 1392 HIVl-infected adnlts in Uganda (14). The vaccine was well tolerated. However, it was ineffective and is not recommended for nse in HIVl-infected indivi-dnals. Reassessment of recommendations for polysaccharide vaccine immunization may be necessary in some countries. The authors suggested that the vaccine causes destruction of polysaccharide-responsive B cell clones. 

Case Conclusion HP began methimazole therapy for her Graves hyperthyroidism. She also began propranolol to help control her tachycardia and tremor. During this time HP should avoid excessive exercise or other sympathomimetic drugs until her symptoms of tachycardia have subsided. HP will return to the clinic for follow-up in 4 weeks. At that time, methimazole dose, tolerability, compliance, and thyroid function tests will be reassessed. 

The new safety standard, provided in section 408(b) (2) (A) (ii) of the FQPA, is a reasonable certainty of no harm standard for aggregate exposure using dietary residues and all other reliable exposure information. When setting new or reassessing existing tolerances or tolerance exemptions under the new standard, EPA must now focus explicitly on exposures and risks to children and infants. EPA must explicitly determine that the tolerance, or exemption from tolerance, is safe for children consider the need for an additional safety factor of up to tenfold to account for uncertainty in the data base relative to children unless there is evidence that a different factor should be used and consider children s special sensitivities and often unique exposure patterns to pesticides. 

Reassessment, within 10 years, of all tolerances issued prior to enactment of EQPA to ensure they meet the new safety standard. 

Because the MRLs are derived from incurred residue concentrations resulting from approved uses, residue concentrations in excess of the MRL represent, by definition, uses outside the conditions on the label. Multiple reassessments of the MRLs may result in revised MRLs that exceed the incurred residue concentrations associated with the original evaluation, thus weakening their direct application to prosecution of label violations. Nevertheless, MRLs provide for a more direct linkage between regulatory decision criteria and the labeled conditions of use than do tolerances. However, because MRLs may result in exposure estimates that are significantly below the ADI, it can be difficult to conclude that residues in excess of the MRLs represent a direct public health concern. 

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