Effect of individual parameter changes on the outcome of the estimated short-term dietary exposure to pesticides

ABSTRACT

In 2015 a scientific workshop was held in Geneva, where updating the International Estimate of Short-Term Intake (IESTI) equations was suggested. This paper studies the effects of the proposed changes in residue inputs, large portions, variability factors and unit weights on the overall short-term dietary exposure estimate. Depending on the IESTI case equation, a median increase in estimated overall exposure by a factor of 1.0-6.8 was observed when the current IESTI equations are replaced by the proposed IESTI equations. The highest increase in the estimated exposure arises from the replacement of the median residue (STMR) by the maximum residue limit (MRL) for bulked and blended commodities (case 3 equations). The change in large portion parameter does not have a significant impact on the estimated exposure. The use of large portions derived from the general population covering all age groups and bodyweights should be avoided when large portions are not expressed on an individual bodyweight basis. Replacement of the highest residue (HR) by the MRL and removal of the unit weight each increase the estimated exposure for small-, medium- and large-sized commodities (case 1, case 2a or case 2b equations). However, within the EU framework lowering of the variability factor from 7 or 5 to 3 counterbalances the effect of changes in other parameters, resulting in an estimated overall exposure change for the EU situation of a factor of 0.87-1.7 and 0.6-1.4 for IESTI case 2a and case 2b equations, respectively.

KEYWORDS:

• Acute dietary exposure
• IESTI
• large portion
• maximum residue limit (MRL)
• pesticide
• supervised trials median residue (STMR)
• highest residue (HR)
• unit weight
• variability factor

Acknowledgments

The experimental work described in this paper was conducted by Trijntje van der Velde-Koerts (RIVM), Christian Sieke (BfR), Nicolas Breysse (ANSES) and Lauriane Pattingre (ANSES). The co-authors of this article took part in the discussions for a thought-out work plan and provided constructive comments. In addition, the authors would like to acknowledge Eveline Adriaans, Jan Dirk te Biesebeek, Coline van den Boogaard, José Drijvers from RIVM for their valuable help in extracting the residue data from the JMPR reports, Jacqueline Siljee (RIVM) for her help in the calculations and Maarten Schipper (RIVM) for drafting most of the figures.

Supplementary Materials

 

Table 1S. Effect of replacement of HR or STMR by MRL (as MRLxCF/HR or MRLxCF/STMR).

Table 2S. Effect of change in large portion parameter (as LP_pers_calc/LP_pers).

Table 3S. Effect of changes in case 2a equations, when only one of the parameters is changed.

Table 4S. List of commodities where a shift from case 2b to case 2a or vice versa is observed.