Hay 23, 196*

Jerome H. Heckman, Esq.
Keller and Heckman
1712 N. Street, N.W.
Washington, D.C.
20036

Dear Jerry:
The following merely points up oar interpretation of the
proposed 8121.2500 (d)(5) and is not intended to provoke
controversy.
It may, nevertheless, suggest posible points worthy
of discussion at our next meeting.
As we read the opening paragraph of subsection (d)(5),
substances which fail the heavy metals test or which are known
to be toxic at diet feeding levels of 40 ppm or less are not
acceptable under this regulation. Presumably, if the material
is not known to be toxic at stated level there is no need to
demonstrate lack of toxicity at higher level.
However, if any
demonstration of lack of carcinogenicity is a requirement, chronic
feeding studies may still be needed.
With respect to sub*subpar. (i) of the proposed regulation,
we agree that actual analysis of food would involve great
difficulty and the 0.05 ppm tolerance is of little value if
100% migration is assumed. Therefore, only the question of what
constitutes "appropriate extraction studies" remains. While
this is certainly less difjtcult than with food, I can visualize
substantial difficulty in analyses for many organic migrants
even with use of simulated solvents, because frequently several
components migrate to a greater or lesser degree. More on this
below.
In (li), free oil on finished food-contact article is
prohibited, except where otherwise permitted. To my limited
knowledge, the only place where surface lubricants are permitted
is on metallic surfaces in 8121.2531. However, I think it is

ASI-PR 0000744

J. H. Heckman, Esq,
Washington, D.C.

2

5/23/1969

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possible, if not probable, that so-called internal lubricants’
in plastics may migrate to surface and yield very thin oily
films on the surface. Thus, as I interpret this paragraph, if
the lubricant is permitted by other regulations it is acceptable
here, but any new substance that may 'bleed' at the surface is
not acceptable.
With respect to (iii), I personally believe that the repeated
use surface should be cleansed with a solvent simulating the
type of food to be used in the container.
In (v), does this mean that only general provisions of
8121.2520 must be complied with or that substance must be listed
in 8121.2520 (c)(5)? Also, is this not the time to eliminate
8121.2520 or to delete the listings, excepting those known to be
toxic at the 40 ppm level, e.g., sodium fluoride.
As with the octyl tin regulation, analytical difficulties
may be encountered in determining whether additive is less than
0.05 ppm in food or even in simulating solvents. Since the total
extractable from many, if not most, food wrappings is greater
than that equivalent to 0.05 ppm in food, the extraction residues
must be analysed for the additive under study and this may not
be easy. Also, unless FDA agrees to a standard ratio of volume
(or weight) to surface area (e.g. 10 ml/sq.in.), package sire
must be considered. Finally, thickness of food contact material
will affect migration. Presumably, thickness could be specified
in same manner as volume to surface area ratio but if thick film
is specified, thin films usually used, will suffer.
In short,
my discussion here questions mathematics to be used with any
simulated solvents demonstration.
I find FDA proposal quite a bit removed from Jack Frawley's
idea.
Very truly yours.
Original Signed
I.. A. Knajp

W. A. Knapp
Consultant-Toxicology
WAK: dunk

cc: Mr. Robert M. Mill r, Hercules, Inc.Dels.
ASI-PR 0000745