Fall 1993 (v5n5)
Committee on Pesticides in the Diets of Infants and Children, National Academy of Sciences
National Academy
of Sciences, National Academy Press, washington, DC. 1993
This National Academy of
Sciences (NAS) study was congressionally mandated in 1988. Its purpose
was to examine the scientific and policy issues faced by government agencies
in regulating pesticide residues in foods consumed by infants and children.
The report concluded that the federal government should change some of
its scientific and regulatory procedures to give infants and children
greater protection from possible adverse health effects of pesticides
in their diets.
The NAS report found age-related
differences in susceptibility, toxicity and exposure to pesticides between
adults and children. Children may be more or less sensitive than adults,
depending on the pesticide to which they are exposed. Due to rapidly changing
processes in infants and children, there is no simple way to predict the
sensitivity to these chemicals from data derived entirely from adults.
The NAS committee found, however, that quantitative differences in toxicity
between children and adults are usually less than a factor of 10. Lack
of data on pesticide toxicity in developing organisms was a recurrent
problem for the committee, so they had to rely mostly on incomplete information
derived from studies of adult animals and on chemicals other than pesticides.
Differences in exposure to
pesticides were generally more important than were age-related differences
in toxicological vulnerability. The committee found that infants differ
both qualitatively and quantitatively from adults in their exposure to
pesticide residues in foods. Children consume more calories of food per
unit of body weight and much more of certain foods, especially processed
foods, than do adults. Water consumption, both as drinking water and as
a food component, is very different between adults and children. Unfortunately,
information on pesticide residues and the effects of processing on residue
concentrations is inadequate for foods eaten by infants and children.
To characterize potential
risks to infants and children, the committee used a statistical technique
that took into account variations in food intake and pesticide residue
levels. The committee applied this technique to determine health risks
under three different scenarios-acute toxic effects, chronic toxic effects,
and simultaneous exposure to several pesticides.
On the basis of its findings,
the committee recommends that changes be made in current regulatory practices.
Estimates of total exposure to pesticide residues should reflect the unique
characteristics of the diets of infants and children and should account
also for all nondietary intake of pesticides. The committee also recommends
that the Environmental Protection Agency (EPA) modify its decision-making
process for setting tolerances so that it is based more on health considerations
than on agricultural practices. Now, although tolerances establish enforceable
legal limits for pesticide residues in food, they are not based primarily
on health considerations and do not provide a good basis for inference
about actual exposures of infants arid children to pesticide residues.
The committee states that "Children should be able to eat a healthful
diet containing legal residues without encroaching on safety margins."
Specifically, six areas should be addressed:
Toxicity testing. Laboratory
tests should be developed for studying toxicity in immature animals to
evaluate the sensitivities of infants, children, and adolescents.
Uncertainty factors. Currently,
if animal tests show no adverse effects at a certain exposure level, an
uncertainty factor of 100 is used to establish guidelines for human exposure.
EPA uses an additional factor of 10 if studies have shown effects on the
developing fetus. The report recommends expanding the use of this additional
uncertainty factor when there is evidence of postnatal toxicity or when
data from toxicity testing relative to children are incomplete.
Food consumption data. The
committee recommends that additional data on the food consumption patterns
of infants and children be collected within narrower age groups. This
would include at every one-year interval up to age 5, between ages 5 and
10, and between ages 11 and 18. These narrower groupings would result
in a more accurate portrayal of the ways children's diets differ from
those of adults.
Pesticide residue data. The
committee recommends the use of comparable analytical methods and standardized
reporting procedures and the establishment of a computerized database
to collate data on pesticide residues from different labs.
Risk assessment. All exposures
to pesticides- dietary and nondietary-need to be considered when evaluating
the potential risks to infants and children. Nondietary environmental
sources of exposure include air, dirt, indoor surfaces, lawns and pets.
Estimation of cancer risk.
The committee recommended the development of new methods that account
for changes in exposure and susceptibility that occur as a person matures.
In summary, the NAS committee's
recommendations support the need to improve methods for estimating exposure
and for setting tolerances to safeguard the health of infants and children.
Pesticides in the Diets
of lnfants and Children is available for $47.95 plus $4.00 shipping
from the National Academy of Sciences, Office of News and Public Information,
2101 Constitution Avenue NW, Washington, DC 20416. Tel. (202) 334- 3313
or (800) 624-6242.
(GWF.012)
Contributed by Gail
Feenstra
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