evaluation of certain food additives - libdoc.who.int - World Health ...

advances in scientific knowledge relevant to the nature or mode of action of
food additives;
changes in consumption patterns or level of use of a food additive; and
improved requirements for safety evaluation. This is made possible by new
scientific knowledge and the quality and quantity of safety data considered
necessary in the case of food additives and residues of pesticides and veterinary
drugs.
The Committee further noted that it is important to take existing assessments
into account in the re-evaluation of a food additive and that a process must
be developed by which the information needed for the re-evaluation can be
provided.
2.3.3 Data adjustment using food frequency questionnaires to better
account for long-term dietary exposure
Risk characterizations for long-term toxicity compare dietary exposure estimates
with the relevant health-based values established for a lifetime. In
previous meetings, the Committee often raised the fact that the use of shortterm
food consumption data to represent long-term dietary habits could lead
to an overestimation of the amount of food consumed per day, in particular
for foods consumed infrequently.
Typically, chronic dietary exposures are based on food consumption data
collected over a period of 1–7 days. The use of surveys of duration longer
than 1 day allows the averaging of the amount of food consumed per day to
give the amount usually consumed. This will reduce the overestimation of
the dietary exposure for chemicals occurring in foods consumed infrequently.
During the current meeting, the Committee examined a submission for an
additive for which the “usual” food consumption data collected over a period
of 2 days had been adjusted to better describe long-term dietary exposures by
the use of food frequency questionnaires that estimated the number of eating
occasions for each food over a period of 30 days for a comparable population.
In this case, data from the 2003–2004 National Health and Nutrition Examination
Survey (NHANES), which reports 2 days of food consumption, had
been combined with data from the NHANES III 30-day food frequency survey
for the population in the USA.
To better assess chronic dietary exposure, the Committee recommends the
use of food consumption data collected over a period of more than 1 day
with an averaging of the amounts of food consumed per day. Moreover, the
Committee recommends that food consumption data collected over a few
days be adjusted by using food frequency questionnaires on a comparable
population where these data are available. This approach would better
represent long-term consumption for foods consumed infrequently. The
7