Yam, Kit L. (ed.). The Wiley encyclopedia of packaging technology

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Pressure-Sensitive Labeling Machines

A pressure-sensitive adhesive is one that remains perma-

nently and aggressively tacky in the dry form and has the

ability to bond instantaneously to a wide variety of

materials solely by the application of light pressure. No

water, solvent, or heat is needed to activate these

materials.

Because the adhesive is permanently tacky, it would

stick to anything it contacted, so a backing sheet is

required to protect the adhesive layer until it contacts

the article to be labeled. The backing sheet is coated with a

release coating to prevent the label from sticking too

ﬁrmly to it (13).

There are many different types of applicators, but they

all have one thing in common: a means of peeling the

labels away from the backing (see Figure 6). This is

usually accomplished by unwinding a reel of die-cut labels

and then pulling them under tension around a stripper

plate. As the backing is bent around a sharp angle, the

front edge of the label peels away. Once the labels have

been detached from the backing, there are various ways of

feeding them forward and pressing them onto the contain-

ers in the correct position. Containers may be fed forward

to an applicator drum where the label is transferred to it

under light pressure created by an applicator drum and

pressure pad. Alternatively, the label may be held in

position on a vacuum box or drum and released onto the

article when it is in the correct position, or it may be blown

onto the container by releasing the vacuum and applying

air pressure. The backing paper is then rewound on a

take-up spool (12).

Comparatively simple systems have been devised to

apply the label to the product. The choice ranges from a

dispenser that releases a label for hand application up to

high-speed automatic labelers. Labeling machines for

applying pressure-sensitive labels vary in complexity

according to the nature of the package to be labeled, the

number of labels to be applied at one time, and the speed

of application. There are, of course, semiautomatic labe-

lers for single-product medium-volume application.

Although pressure-sensitive labelers are available as

standard machines, they are usually readily customized

to meet special requirements. Generally, they are only

about one-third to one-half the cost of most competitive

labeling systems.

The advantages of pressure-sensitive labels are said to

be numerous. They are cleaner than other methods, less

wasteful than wet glue, and more easily controlled be-

cause they come in roll form so that labels cannot be mixed

up. A wide variety of adhesives for different surfaces is

available, and clear acetate, vinyl, or polyester ﬁlm can be

used for ‘‘see-through’’ labels.

Heat-Seal Labeling Machines

Heat-seal labeling has most of the advantages of pressure-

sensitive labels but generally offers a lower label cost.

Heat-seal describes a plasticized paper which, when

heated by the machine, becomes sticky on its underside.

Labeling equipment for heat-seal ranges from simple aids

to automatic high-speed machines, giving the unique

advantage of being able to apply to many varied types of

surface labels that can be precision-placed, give allover

adhesion, and be perfectly clean when applied.

The machines free the user from mixing and adding

glue, selecting grades, controlling viscosity, and so on. The

absence of glue eliminates cleaning the machine, and

these savings give substantial increases in productivity

and reductions in maintenance expenses. The labels offer

a high degree of adhesion security that is useful, for

example, for bottles subjected to high humidity, or steam

of water saturation (14).

Of the two types of heat-seal paper, the delayed-action

type is best suited for machine operation. The ability of the

adhesive to remain tacky after removal of the heat source

allows the machine designer to separate the heat source

from the pressure application of the label. Thus the

heating plates can be simple whereas the pressure-apply-

ing devices can be of complex shapes, enabling a diverse

range of articles to be labeled, varying from ﬂat to round

or irregular shapes (10).

LABEL OVERPRINTING MACHINERY

For certain label applications there is a requirement

to have a plain paper or preprinted label or labels

Figure 6. A common type of self-adhesive label

applicator.

638 LABELS AND LABELING MACHINERY

overprinted with price, price/weight, bar code, or other

variable information just prior to or at the point of

application. A variety of mechanical, electronic, or compu-

ter-based overprinting systems are available for such

operations. These are now widely used by department

stores, the retail and wholesale trade, industry, and even

some label producers.

Mechanical overprinting systems range from small

hand-operated machines with one or two wheelsets and

two type channels, to hand-operated and electronic ver-

sions used for price/description labeling with either con-

ventional or EDP-readable fonts (10).

The current trend in overprinting is away from mechan-

ical to totally electronic overprinters, which can now print

labels and tags without any form of marginal or sprocket-

hole punching. Free formating and graphics, as well as

alphanumeric information and bar codes, are now possible

using such overprinting technology, the graphics being

keyboard entered and edited. Graphics suitable for repro-

duction include product outlines, such as shoes, laboratory

equipment, small hardware items, safety hazard designs,

and laundry symbols. Figure 7 shows examples of such

electronically produced and overprinted graphics.

BIBLIOGRAPHY

M. C. Fairley, ‘‘Labels and Labeling Machinery’’ in M. Bakker, ed.,

The Wiley Encyclopedia of Packaging Technology, 1st edition,

John Wiley & Sons, New York, 1986, pp. 424–430.

Cited Publications

1. A Guide to Legislation and Standards on Labelling (UK),

Labels & Labeling Data and Consultancy Services Ltd,

Potters Bar, Herts, UK, 1984.

2. D. G. N. Alder, ‘‘Label Papers and Their Uses,’’ Labels &

Labelling 14, 16 (1979).

3. ‘‘The Most Important Types of Paper for Beverage Labels,’’

Krones Manual of Labelling Technology, Hermann Kronseder

Maschinefabrik, Neutraubling, FRG, 1978, pp. 118–121.

4. A. Hildrup, ‘‘Review of the (UK) Gummed Paper Market,’’

Labels & Labelling Yearbook, 16, 23 (1981).

5. M. Fairley, ‘‘The Challenge for Water-Borne Adhesives,’’ La-

bels & Labelling, 19, 29 (1984).

6. M. Fairley and R. Brown, Thermal Labelling, Labels &

Labelling Data and Consultancy Services Ltd., Potters Bar,

Herts, UK, 1984.

7. M. Fairley, Bar Coding, Labels & Labelling Data and Con-

sultancy Services Ltd., Potters Bar, Herts, UK, 1983.

8. N. Henderson, ‘‘Trends and Developments in Heatseal Label

Materials,’’ Labels & Labelling Yearbook 16, 31 (1981).

9. M. Fairley, Label Printing Processes and Techniques, Labels &

Labelling Data and Consultancy Services Ltd., Potters Bar,

Herts, UK, 1984.

10. Labels—A Product Knowledge Book, National Business

Forms Association, Alexandria, VA, 1983.

11. Labelling Operations, Pira, The Research Association for the

Paper and Board, Printing and Packaging Industries,

Leatherhead, Surrey, UK, 1981.

12. E. Pritchard, ‘‘Labelling, and Labelling Systems,’’ Labels &

Labelling, 17, 16 (1982).

13. Labelling—Basic Principles, Pira, The Research Association

for the Paper and Board, Printing and Packaging Industries,

Leatherhead, Surrey, UK, 1980.

14. D. Miles, ‘‘Pre-adhesed Labelling,’’ Labels & Labelling, 16,20

(1981).

15. M. Noah, The Tadbik Group, personal communication (2008).

LAWS AND REGULATIONS, UNITED STATES

RALPH A. SIMMONS

Keller and Heckman

Washington, DC

There is no single body of law or regulations pertaining

to all aspects of the manufacture, distribution, and use

of packaging in the United States. Many different types

of federal, state, and even local laws and regulations

affect the packaging industry. These laws and regulations

can be separated into two broad categories: (a) those that

pertain directly to the packaging itself and (b) those that

pertain generally to manufacturing and commercial

transactions, including packaging among many other

products.

This article focuses on the former category of legal

requirements pertaining most directly to packaging.

These include health and safety regulations of packaging

materials, labeling requirements, and environmental laws

and regulations relating to the disposal of packaging.

FDA’S REGULATORY FRAMEWORK FOR PACKAGING

The Food and Drug Administration (FDA) has primary

regulatory authority in the United States over the safety

of packaging used for food, drugs, cosmetics, and medical

devices to the extent the products are in interstate com-

merce (which they almost always are).* The packaging for

these products is regulated by the FDA so that it does not

Figure 7. Electronically produced graphics are available on

electronic label overprinters.

* The U.S. Department of Agriculture (USDA) technically has

authority over packaging used in federally inspected meat and

poultry processing plants. However, in practice, USDA does not

independently evaluate the safety of packaging materials, defer-

ring to FDA on this issue.

LAWS AND REGULATIONS, UNITED STATES 639

cause the products themselves to become contaminated or

‘‘adulterated’’ in violation of the Federal Food, Drug and

Cosmetic Act.

The most extensive of FDA’s packaging regulations are

the ‘‘food-additive regulations,’’ which provide ofﬁcial per-

mission for the use of substances as food ingredients

(direct additives), and as components of food packaging

or other food-contact materials (indirect additives). The

FDA does not have regulations clearing speciﬁc materials

for use in packaging for drugs, medical devices, or cos-

metics. In the case of drugs and medical devices, packa-

ging materials are reviewed and approved by the FDA in

the context of approving the drug and medical-device

products themselves, if such approval is necessary. The

FDA does have a general requirement for tamper-resis-

tant packaging for over-the-counter (OTC) drugs. Suppli-

ers of packaging materials to drug and medical-device

manufacturers typically assist those manufacturers in

obtaining FDA approval by providing information on the

packaging to the FDA through a conﬁdential drug or

device master ﬁle. Neither cosmetic products nor their

packaging are subject to premarket clearance by the FDA;

it is up to the cosmetics manufacturer and its packaging

suppliers to ensure that the products and packaging are

safe for their intended use.

Deﬁnition of Food Additive. The FDA’s regulation of

food packaging is based on Section 201(s) of the Federal

Food, Drug and Cosmetic Act. Section 201(s) of the Act

deﬁnes a food additive, in relevant part, as follows:

[A]ny substance the intended use of which results or may

reasonably be expected to result, directly or indirectly, in its

becoming a component y of any food y if such substance is

not generally recognized y to be safe under the conditions of

its intended use; except that such term does not include y

(4) any substance used in accordance with a sanction or

approval granted prior to the enactment of this paragraph

pursuant to this Act (4)

Section 409 of the Act requires that a food additive, as

deﬁned above, must be the subject of an applicable food-

additive regulation.

Thus, substances used in food-

contact applications that, under their intended conditions

of use, may reasonably be expected to become components

of food are ‘‘food additives’’ and can be used only in

accordance with an applicable food-additive regulation

unless they are either (a) the subject of a prior sanction

or approval granted by FDA or the U.S. Department of

Agriculture (USDA) prior to the enactment of the Food

Additives Amendment of 1958 or (b) generally recognized

as safe (GRAS). If the substance is not reasonably ex-

pected to become a component of food under the intended

conditions of use, however, it is not a food additive within

the meaning of Section 201(s) of the Act, and may be used

as intended without the need for consultation with or prior

action by the FDA

The Food-Additive Regulations. The FDA’s food-additive

regulations, found in Title 21, Parts 170–197 of the Code of

Federal Regulations (CFR), cover both direct and indirect

additives. The term ‘‘direct food additive’’ commonly refers

to materials directly and intentionally added to foods to

perform a functional effect in the food. The term ‘‘indirect

food additive’’ generally refers to substances that are not

intended to, but nevertheless become, components of food

as a result of use in articles that contact food (e.g.,

substances used in packaging materials).

Over the years, indirect food-additive regulations have

been promulgated in response to individual food-additive

petitions with no overall structural scheme. This has led to

the existence of three general types of indirect food-additive

regulations: those that clear speciﬁc polymers (e.g., Section

177.1520, applicable to polyoleﬁns), those that clear sub-

stances categorized by function (e.g., Section 178.3400,

applicable to emulsiﬁers and surface-active agents), and

those that list substances that may be used in speciﬁc types

of packaging (e.g., Section 176.170, applicable to compo-

nents of paper and paperboard). F or this reason, a great

deal of overlap among different regulations has occurred.

A major limitation on the types of substances that may

be listed in the food-additive regulations is the so-called

Delaney Clause of the Federal Food, Drug and Cosmetic

Act. The Delaney Clause prohibits the FDA from issuing

regulations permitting the use as food additives of sub-

stances that are ‘‘found to induce cancer when ingested by

man or animals’’ (1).

The FDA has mitigated the impact of the Delaney

Clause, however, by interpreting it to apply to the ﬁnished

food ingredient or food-contact material itself, not to

constituents or components of the food additive (e.g., the

Delaney Clause applies to polymers used to make food

packaging but not to monomers used to make the poly-

mers). This ‘‘constituents policy’’ is not set forth in any law

or regulations but is applied by the FDA in evaluating food

additive petitions, was described by FDA in an Advance

Notice of Proposed Rulemaking, and has been upheld by

the courts (2).

Prior-Sanction Exemption. The Federal Food, Drug

and Cosmetic Act speciﬁcally exempts from the deﬁnition

of a food additive any substance that is ‘‘prior-sanctioned,’’

which means any substance permitted for its intended use

by an FDA or USDA letter or memorandum written prior

to the Food Additives Amendment of 1958. Unfortunately,

no authoritative master list exists for the materials cov-

ered (3).

If a company has any such letters in its ﬁles or

knows of any relevant ones elsewhere, they can be relied

on, but the FDA interprets such letters narrowly.

‘‘Generally Recognized as Safe’’ Exemption. Another ex-

emption from the food additive deﬁnition pertains to

Food that contains an uncleared food additive is considered

‘‘adulterated’’ and would be subject to adverse FDA regulatory

action.

The Food Chemical News Guide, commonly known in industry

as the ‘‘Knife and Fork’’ book, contains listings of both direct and

indirect food additives and their status under the Food and Drug

Regulations; the ‘‘Knife and Fork’’ book also documents public

‘‘prior sanctioned’’ status of substances. The Guide is regularly

updated.

640 LAWS AND REGULATIONS, UNITED STATES

GRAS substances. Section 174.5(d)(1) of the Food Additive

Regulations states that substances generally recognized

as safe ‘‘among experts qualiﬁed by scientiﬁc training and

experience to evaluate their safety’’ are permitted to be

used as components of articles that contact food. Parts

182, 184, and 186 of the Food Additive Regulations

provide a listing of some substances that are considered

by the FDA to be GRAS, but the substances actually listed

in the regulations by no means constitute all substances

that are GRAS.

Section 182.1 of the Food Additive

Regulations makes it clear that the GRAS listings are by

way of illustration and do not represent an all-inclusive

list. Furthermore, the absence of a substance from the list

does not preclude a company from making a self-determi-

nation that its products are GRAS, where such a determi-

nation is supported by the available information.

The FDA has codiﬁed requirements for the classiﬁca-

tion of food additives as GRAS under 21 CFR 170.30(a). As

stated in that provision, general recognition of safety must

be based on (a) scientiﬁc procedures or (b) in the case of a

substance used in food prior to January 1, 1958, through

experience based on common use in food. The general

recognition of safety requires a ‘‘common knowledge’’

about the substance throughout the scientiﬁc community

about the safety of substances directly or indirectly added

to food. For substances not widely used in food prior to

1958, general recognition of safety requires the same

quantity and quality of scientiﬁc evidence as is required

to obtain approval of a food additive regulation for the

ingredient. Unlike a food-additive petition, however, gen-

eral recognition of safety is ordinarily based on published

studies that may be corroborated by unpublished studies

and other data and information (4).

The exclusion of GRAS substances from the deﬁnition

of the term ‘‘food additive’’ means that such substances do

not require premarket clearance by the FDA. Any manu-

facturer who determines that a particular substance is

GRAS is free to market the substance without notiﬁcation

to, or approval by the FDA. Obviously, if the FDA should

consider the manufacturer’s determination of GRAS sta-

tus to be erroneous, then the Agency can take appropriate

regulatory action; in such a case, the burden of proof

would fall on the FDA to demonstrate that the substance

is not GRAS. This is an unlikely consequence unless a real

public-health problem is presented.

A manufacturer who pursues a self-determined GRAS

position for a substance can also ﬁle a GRAS Afﬁrmation

Petition (GRASP) with the FDA seeking the Agency’s

concurrence. In contrast to a Food Additive Petition, if a

GRASP is accepted by the FDA for ﬁling, then the peti-

tioner may market the product while the petition under-

goes technical review because FDA has been informed of

the manufacturer’s determination that the product is

GRAS and has raised no objection. However, unlike a

Food Additive Petition, all materials submitted in support

of the GRASP become immediately available in full to the

public, and even manufacturing details cannot be kept

conﬁdential. The requirements and type of information a

petitioner must supply for a GRASP are spelled out in 21

CFR y 170.35.

The ‘‘No-Migration’’ Exemption. One of the most impor-

tant means of establishing satisfactory FDA status for an

indirect additive is to establish a rational basis on which

to conclude that there is no reasonable expectation of the

substance becoming a component of food. If a substance is

not reasonably expected to become a component of food

under its intended conditions of use, it is not a food

additive by deﬁnition and, therefore, may be so used

without obtaining any FDA ‘‘approval.’’ Unfortunately,

the FDA has not provided deﬁnitive, objective criteria

for determining when a substance in a food-packaging

material may reasonably be expected to become a compo-

nent of food. Nevertheless, reliable guidance is available

from at least two different sources:

1. Ramsey Proposal. The ﬁrst source of guidance is a

proposal circulated by the FDA as its response to

widespread criticisms by the food-packaging industry

at the National Conference for Indirect Additives held

in Washington, DC in February 1968. This so-called

Ramsey proposal would have acknowledged in a

regulation the propriety of the use, without the prior

promulgation of a food-additive regulation, of sub-

stances that will transfer from packaging or other

food-contact articles to food at levels no higher than

50 parts per billion (ppb); components of articles used

in contact with dry, nonfatty foods; and components of

articles intended for repeated use in contact with

bulk quantities of food. This would have applied to all

substances except those known to pose some special

toxicological concern, such as a heavy metal, which is

a known carcinogen, or something that produces toxic

reactions at levels of 40 parts per million (ppm) or less

in the diet of humans or animals. Although never

formally adopted, the standards in the Ramsey pro-

posal were deemed scientiﬁcally acceptable and have

been generally honored by the FDA either explicitly

or by its having taken no enforcement action in cases

where the criteria are met.

2. Monsanto v Kennedy. The second source of clariﬁca-

tion of the ‘‘food additive’’ statutory deﬁnition is

provided by a U.S. Court of Appeals decision. In

Monsanto v Kennedy, 613 F.2d 947 (D.C. Cir. 1979)

the FDA argued that any contact of a packaging

material with food must result in some transfer of

the packaging constituent to the contained food. The

Court rejected this argument and stated:

Congress did not intend that the component requirement

of ‘‘food additive’’ would be satisﬁed by y a mere ﬁnding

of any contact whatever with food.y For the component

element of the deﬁnition to be satisﬁed, Congress must

have intended the Commissioner to determine with a fair

degree of conﬁdence that a substance migrates to food in

more than insigniﬁcant amounts (5).

Role of Extraction Studies. On the basis of the Ramsey

proposal and the Monsanto precedent, it is widely

Idem. The ‘‘Knife and Fork’’ book also documents ﬁlings and

status of petitions to FDA for listing of substances as GRAS in the

regulations.

LAWS AND REGULATIONS, UNITED STATES 641

accepted that if extraction testing properly simulating the

intended conditions of use for a potential additive does not

yield detectable migration of the additive or its compo-

nents at an appropriate analytical sensitivity, then the

substance is not reasonably expected to become a compo-

nent of food under these conditions and, thus, is not a food

additive within the meaning of Section 201(s) of the Act.

The industry generally considers a ﬁnding of ‘‘nonde-

tected’’ in a properly conducted migration study using

methods sensitive to the equivalent of 50 ppb of the

substance in contacted food to be a sound basis for

concluding that a substance is not a food additive. How-

ever, in some cases, it is necessary to make use of

analytical methodology that can detect as little as 10 ppb

or even 1 ppb to support a ‘‘no-migration’’ determination

because of the sensitive nature of the material being used,

such as a heavy metal or a substance for which there will

be a high level of use, such as milk or soda containers.

General Adulteration Provision. If the packaging mate-

rial is not reasonably expected to become a component of

food and is, therefore, not a food additive, it is still subject

to the nonadulteration provision of the Act. The FDA

sometimes refers to this as the general safety clause,

contained in Section 402 of the Act. This general prohibi-

tion against adulteration is the basis for the FDA’s ‘‘good

manufacturing practice’’ regulation, which requires that

‘‘[a]ny substance used as a component of articles that

contact food shall be of a purity suitable for its intended

use’’ (6). Fortunately, the same analysis that demonstrates

that a material will not become a component of food will

also satisfy the Act’s general safety requirements for food-

packaging material, speciﬁcally, that the packaging will

not adulterate the food by rendering it injurious to health.

The ‘‘Basic Resin Doctrine’’ Exemption. A signiﬁcant

characteristic of the Food Additive Regulations is that

the FDA clears substances on a generic rather than a

proprietary basis. In the case of resins and polymers, as

long as the basic resin is listed in a regulation, is manu-

factured in accordance with good manufacturing prac-

tices, and complies with applicable limitations such as

stated extraction requirements, it is covered by that

regulation even though different manufacturers may

make the resin by different processes and employ different

catalysts, reaction control agents, and the like.

A ‘‘basic polymer’’ is the material that comes out of the

polymerization ‘‘kettle’’ or reactor, that is, the product that

results when the polymerization process has been carried

to commercial completion. Substances such as catalyst

residues, chain-transfer agents, minor comonomers, and

other materials required to produce the basic resin are

considered a part of it and are not subject to independent

regulatory consideration. The FDA’s basis for this princi-

ple is that, where a substance is used only in a small

quantity and either becomes part of the resin during

polymerization, or is washed from the resin at the conclu-

sion of polymerization, its potential for signiﬁcant migra-

tion is minimal. In other words, there is no reasonable

expectation of migration, and therefore the substance is

not considered an independent food additive.

The basic polymer doctrine also reﬂects the practical

reality that the FDA cannot write generic regulations for

food-packaging materials that describe and speciﬁcally

clear every substance that might properly be a trace

component or contaminant of the packaging material as

a result of every manufacturing process that yields a

suitable resin. Because trace quantities of these ‘‘unregu-

lated substances’’ are not perceived to present a public-

health hazard, the FDA has wisely chosen not to subject

these substances to the burdensome preclearance provi-

sions of Section 409 of the Act that apply to food additives.

Generally speaking, it is reasonable to consider cata-

lysts and minor comonomers to be covered by the basic

polymer doctrine when used at levels of up to approxi-

mately 0.5%; between this level and 1%, the substance and

use in question must be evaluated on a case-by-case basis.

At levels above 1%, the basic polymer doctrine is not

considered applicable.

Even if a component of a food-contact material falls

within the basic-polymer doctrine, the ﬁnished food-

contact material must still satisfy the necessary purity

requirements of the Food Additive Regulations; that is, it

must be of a purity suitable for its intended use, as

required under 21 CFR y 174.5(a)(2). Obviously, if a

particular catalyst being used were to render a ﬁnished

food-contact material unsafe or unﬁt for its use, that

material would not satisfy the purity requirements.

The Housewares Exemption. The components of eating

utensils, receptacles, paper towels, or other kitchenware,

sold as such, are outside the scope of coverage of the Food

Additive Amendments of 1958, and therefore these pro-

ducts do not require premarket clearance by the FDA.

This has come to be called the ‘‘housewares’’ exemption.

This exemption is grounded on a declaration of intent in

the legislative history of the 1958 Food Additives Amend-

ment. The following statement appears in the ofﬁcial

record of the debate on the Amendment and was made

by the ﬂoor manager of the bill, The Honorable John Bell

Williams, Chairman of the House Subcommittee on

Health and Science:

I have been asked since the Committee report of the bill what

is meant by a substance ‘‘holding’’ food, as mentioned in the

bill. An example of what is meant by this would be a plastic

ﬁlm or paper wrapper which surrounds the package of food.

This bill is not intended, for example, to give the Food and

Drug Administration the authority to regulate the use of

components of dinnerware or ordinary eating utensils (7).

The FDA has written many letters afﬁrming this ex-

clusion. The exclusion of housewares from the need for

ﬁling foodadditive petitions is a recognition that such

products generally do not give rise to any public-health

concern. However, the FDA does take action against

products falling within the housewares exemption in in-

stances involving migration of a substance, such as lead,

which has been proven to pose a true public health

concern.

Threshold of Regulation. The exemptions from the

FDA’s premarket clearance authority discussed so far all

642 LAWS AND REGULATIONS, UNITED STATES

have one important characteristic in common—a company

is entitled to determine for itself whether the exemptions

apply and whether no consultation with or concurrence by

the FDA is required. The FDA recently has adopted an

additional exemption that only the Agency itself may

apply, which is called the Threshold of Regulation.

In 1995, the FDA published the ﬁnal rule establishing

the Threshold of Regulation, which is the FDA’s ‘‘process

for determining when the likelihood or extent of migration

to food of a substance used in a food-contact article is so

trivial as not to require regulation of the substance as a

food additive’’ (8). The ‘‘threshold’’ level is deﬁned as a

dietary concentration of 0.5 ppb or less. The threshold for

substances that have been cleared by the FDA as direct

additives is that the indirect or packaging use must be

limited to 1% or less of the acceptable daily intake

established by the Agency for the direct use of the

substance. To be eligible for the exemption, the food-

contact material must not be a carcinogen and must not

contain carcinogenic impurities that are more potent than

a certain level deﬁned in the regulation (the impurity

cannot have a TD

value of o6.25 mg/kg bw (body

weight) per day, with TD

deﬁned as the feeding dose

that causes cancer in 50% of the test animals.

The FDA has reserved to itself the authority to grant

ofﬁcial exemptions from regulation under the Threshold of

Regulation Rule. However, in proposing the Rule, the FDA

explicitly recognized the continuing right of a company to

determine on its own ‘‘that a particular use of a substance

does not meet the deﬁnition of a food additive’’ (9). There-

fore, companies continue to be entitled to determine for

themselves whether the ‘‘no migration’’ exemption or any

of the other exemptions from the deﬁnition of ‘‘food

additive’’ apply to a particular intended use of a food-

packaging material.

The Food-Additive Petition Process. If none of the ex-

emptions from the FDA’s premarket food-additive regula-

tory authority is available for a packaging material, then

regulatory clearance must be obtained from the FDA

through a food-additive petition. Section 409(b) of the

Federal Food, Drug and Cosmetic Act permits any person

to petition the FDA for a regulation prescribing the

conditions under which an additive may be safely used.

The Act delineates generally the type of information to be

submitted in support of a petition and the procedures and

substantive parameters to be followed by the FDA in

considering a petition. Additional detail on these informa-

tion requirements and procedures is provided in Part 171

of the Food Additive Regulations.

Reduced to its fundamentals, a food-additive petition

must describe the substance to be cleared, provide an

estimate of the quantity that will enter the diet, and

demonstrate that this quantity will be safe. The Act re-

quires the FDA to act on a petition within 90 days, with one

extension for an additional 90 days available to the Agency.

In practice, few petitions are acted on in 18 months or less,

and most are under review for at least 2–3 years.

In 1995, several industry groups representing food

manufacturers and their packaging suppliers revived their

efforts to reform the legal system for food-additive

regulation by the FDA. The basic goals of this effort are

to replace the Delaney Clause with a negligible risk stan-

dard based on sound science and to require the FDA to

accelerate the process of reviewing food-additive petitions.

With respect to packaging materials, the proposed reforms

would replace the petition process with a premarket noti-

ﬁcation system. The FDAwould have 120 days to review the

data on a new packaging material. The material would be

permitted for use at the end of the 120-day period unless

the FDA objected on the basis of real safety concerns.

FDA Regulation of Recycled Materials for Food Packaging.

A specialized area commanding much attention in the

early 1990s has related to the recycling of postconsumer

waste materials, which includes their use in some cases to

make food packaging. There is no legal requirement to

obtain any special or new FDA ‘‘approval’’ for the use of

recycled material in food packaging. The FDA has no

special regulations governing recycled materials, with

the exception of a regulation on recycled paper that merely

restates the universal FDA requirement that all food-

contact materials must be suitably pure for their intended

use (10). The Agency generally regulates food-contact

materials on the basis of their composition, not on the

speciﬁc process by which they are manufactured or the

source of the raw materials. Any food-contact material

(whether plastic, glass, metal, or paper and whether virgin

or recycled) must meet the safety requirements of the Act

and the speciﬁcations and limitations of any food-additive

regulations applicable to the generic type of material (11).

Although no FDA approval is required for recycled

content in food packaging, the requirements of food compa-

nies for assurance that recycled materials are safe has

resulted in a common industry practice of seeking an ofﬁcial

blessing from the FDA, particularly with respect to recycled

plastics. These blessings take the form of so-called no-

objection letters from the FDA. The Agency generally

applies the ‘‘Threshold of Regulation’’ analysis to requests

for these letters, requiring a showing that any potential

contaminants in the recycled material have been reduced to

the ‘‘threshold’’ dietary concentration of 0.5 ppb or below.

ENVIRONMENTAL LAWS AND REGULATIONS

The Federal Role: Environmental Protection Agency (EPA).

The EPA, which is the primary federal agency responsible

for regulating waste disposal, has broad authority over the

management of solid waste under the Resource Conserva-

tion and Recovery Act (RCRA) (12),

as well as the Clean Air

Act (13), the Clean Water Act (14), and the Comprehensive

Under the complex RCRA statute, Congress has divided waste

management into two discrete universes: hazardous waste, which

is regulated under subtitle C of the statute (42 USC 6901), and all

other waste, which is regulated under subtitle D. Most packaging

waste is subject to subtitle D, which governs MSW. During the

past decade, most of EPA’s resources have been directed toward

toughening standards for land disposal of subtitle C hazardous

waste to make them commensurate with pollution controls al-

ready in place for air emissions and water discharges under the

Clean Air Act and Clean Water Act.

LAWS AND REGULATIONS, UNITED STATES 643

Environmental Response, Compensation and Liability Act

(15) (commonly referred to as ‘‘Superfund’’). This authority

includes the power to set standards for the design and

operation of landﬁlls and incinerators and other modes of

waste disposal.

In general, EPA’s modus operandi for dealing with

solidwaste management issues, particularly issues con-

cerning packaging, has been to make recommendations,

such as on preferred options for waste disposal, but to

leave much of the actual regulation of waste to state and

local ofﬁcials.

At this time, the EPA has no speciﬁc rules

governing the disposal of postconsumer packaging waste.

State Regulation. A few states have adopted bans or

other limitations on packaging that does not meet certain

standards of ‘‘environmental acceptability.’’ The criteria of

environmental acceptability in these proposals are typi-

cally that the packaging be recycled at a speciﬁed rate, be

reusable, or be made from recycled materials.

California enacted a law in October 1991 that pur-

ported to ban, as of January 1, 1995, rigid plastic contain-

ers that (a) are not composed of 25% postconsumer

material; (b) do not have a recycling rate of 25% (55% in

the case of PET containers, if measured separately); (c) are

not source-reduced by 10%; or (d) are not reusable or

reﬁllable ﬁve times (16).

The statute contains signiﬁcant waiver and exemption

provisions. The state will waive the postconsumer mate-

rial content requirement if it ﬁnds that (a) the containers

cannot meet the content requirement and remain in

compliance with FDA regulations or other state or federal

laws or regulations or (b) the use of containers meeting the

content requirement is ‘‘technologically infeasible.’’ The

statute also exempts containers for food, cosmetics, drugs,

medical devices, medical food, or infant formula.

Oregon has a statute nearly identical to California’s

(17). The Oregon law has a permanent exemption for food

packaging, except for beverage containers.

Wisconsin has a law purportedly requiring 10% re-

cycled content in plastic containers (18). However, this

law will go into effect for FDA-regulated products only if

the FDA has ‘‘approved’’ the use of recycled content

through a ‘‘formal’’ procedure. So far, FDA’s ‘‘no-objection

letter’’ approach to permitting recycled materials has not

been recognized by Wisconsin as a ‘‘formal’’ procedure.

Wisconsin also has banned recyclable packaging from

landﬁlls and incinerators (19), but has been granting a

series of 1-year waivers for certain plastic packaging that

is not widely collected for recycling.

Nine states have deposit laws that place a surcharge

on certain beverage containers, and provide a refund

of the surcharge to consumers who return the containers

for recycling.** California has its own modiﬁed form of

deposit law, known as AB (Assembly Bill) 2020, under

which, in addition to collection and refund of deposits,

industry may be assessed fees on the basis of costs of

recycling.

CONTROL OF ALLEGED TOXIC SUBSTANCES IN

PACKAGING

State Restrictions on the Heavy-Metal Content of Packa-

ging. Eighteen states

have enacted statutes restricting

lead, cadmium, mercury, and hexavalent chromium in

inks, dyes, pigments, adhesives, stabilizers, and other

components of packaging. These laws are based on model

legislation developed by the Coalition of Northeastern

Governors (CONEG).

California’s Proposition 65. Perhaps the most far-

reaching state environmental law directly affecting packa-

ging and other consumer products is California’s Safe

Drinking Water and Toxic Enforcement Act,

which is

popularly known as ‘‘Proposition 65.’’ Proposition 65,

approved by California voters as an initiative in 1986, is

a right-to-know law that requires companies to either

establish that their products are not likely to expose

any individual to a ‘‘signiﬁcant’’ amount of any of over

400 chemicals, or to provide a ‘‘clear and reasonable’’

warning that the product contains a known carcinogen

or reproductive toxin. To avoid the warning requirement,

a manufacturer must establish that exposure to a chemi-

cal listed under Proposition 65 from a particular package

or other product presents ‘‘no signiﬁcant risk.’’ The

state has established ‘‘no signiﬁcant risk levels’’ for

some, but by no means all, of the substances listed under

Proposition 65.

LABELING

For most packaging, the requirements pertaining to label-

ing will depend on the nature of the product contained

within the package. Many products require only that the

labeling not be false or deceptive. This standard is en-

forced on a nationwide basis by the Federal Trade

Commission (FTC)

and by appropriate authorities in

each state, enforcing the so-called ‘‘Little FTC Acts.’’

EPA advocates, but does not mandate, an integrated waste

management approach based, in order of preference, on (a) source

reduction, (b) recycling and composting, (c) incineration, and

(d) land disposal (EPA, 1989).

The nine states with deposite laws are Connecticut, Delaware,

Iowa, Maine, Massachusetts, Michigan, New York, Oregon, and

Vermont.

The 18 states that have adopted versions of the CONEG heavy-

metals restrictions are Connecticut, Florida, Georgia, Illinois,

Iowa, Maine, Maryland, Minnesota, Missouri, New Hampshire,

New Jersey, New York, Pennsylvania, Rhode Island, Vermont,

Virginia, Washington, and Wisconsin.

California Health & Safety Code y 25249.5-.13.

The FTC regulates false, deceptive, or misleading advertising

pursuant to authority granted the Agency under section 5 of the

Federal Trade Commission Act [15 USC y 45(a) (1)], which

prohibits unfair or deceptive acts and practices affecting inter-

state commerce. The Commission has interpreted the act as

essentially requiring companies to be able to substantiate the

truthfulness of both express claims and any inferences a reason-

able consumer is likely to draw from the express claim.

644 LAWS AND REGULATIONS, UNITED STATES

Certain products, however, are subject to special label-

ing laws and regulations, frequently for health or safety

reasons.

FDA Regulation. The FDA regulates the labeling on

packaging for foods, drugs, cosmetics, and medical devices.

The Federal Food, Drug, and Cosmetic Act prohibits the

‘‘misbranding’’ of FDA-regulated products. A product is

‘‘misbranded’’ if its labeling is ‘ ‘false or misleading, ’ ’ or if it

violates other speciﬁc statutory or regulatory requirements .

The FDA has issued separate regulations pertaining to

the labeling of foods, drugs, cosmetics, and medical de-

vices. The food labeling regulations are the most extensive

of the group and now include a requirement for nutrition

labeling on most food packages.

Packaging and Labeling of Hazardous Materials. The U.S.

Department of Transportation (DOT) regulates the packa-

ging and labeling of hazardous materials for interstate

shipment (and has proposed extending its regulations

to intrastate shipments as well). The authorized types

of packaging and the required labeling vary according

to the degree of hazard presented by a particular

material (21).

ENVIRONMENTAL ADVERTISING AND LABELING

Federal and State Guidelines. Labeling and advertising

claims about the environmental attributes of packaging or

products are not subject to special laws or regulations at

the federal level or in most states. The permissibility of

particular claims generally is tested according to the ‘‘false

or deceptive’’ standard of the Federal Trade Commission

Act and similar state laws.

Both federal and state authorities have issued guide-

lines for applying the ‘‘false or deceptive’’ standard to

environmental labeling and advertising. In July 1992,

the FTC released its Guidelines for Environmental Mar-

keting Claims. The Guidelines address eight categories of

claims: general claims such as ‘‘environmentally friendly,’’

degradable claims, compostable claims, recyclable claims,

recycled content claims, source-reduction claims, reﬁllable

claims, and ozone-safe/ozone-friendly claims. The FTC is

currently reviewing its Guidelines to determine whether

they should be modiﬁed to be more effective. The Guide-

lines do not have the force of law but are considered

authoritative statements of the way in which the FTC

will exercise its enforcement authority. A task force of

the state attorneys general also issued guidelines in 1991,

known as the Green Report II, addressing the same types

of claims covered by the FTC Guidelines, but taking

a more restrictive approach. In the absence of formal

regulations issued by the FTC, states can enforce stricter

limitations on environmental claims than would the

FTC.

State Regulation. A few states have actually adopted

laws or regulations limiting environmental claims

for products and packaging. Two states, California

and Indiana, enacted laws governing environmental

advertising, including use of such terms as ‘‘recycled’’

and ‘‘recyclable’’ (22). California’s law was challenged

in court as an infringement on commercial free speech

(23). Although most of the law was left intact when the

United States Supreme Court declined to hear the case,

California subsequently repealed the essential provisions

of the law. Indiana’s law as enacted was similar to

California’s, but the state now defers to the FTC’s

Guidelines.

Some states, such as New York and New Hampshire,

speciﬁcally restrict use of the terms ‘‘recycled’’ and ‘‘re-

cyclable’’ (24). Both New York and New Hampshire re-

strict the use of the term ‘‘recycled’’ to products containing

a certain minimum percentage of postconsumer material.

They also require signiﬁcant levels of recycling for a

package or product to be labeled ‘‘recyclable.’’

BIBLIOGRAPHY AND NOTES

1. 21 United States Code (USC) y 248 (c) (3) (A).

2. 47 Federal Register 14464 (April 2, 1982); Scott v Food

and Drug Administration, 728 F.2d 322 (6th Cir. 1984).

3. Food Chemical News Guide, published by Food Chemical

News, Inc.

4. 21 Code of Federal Regulations (CFR) y 170.30 (b).

5. Monsanto v Kennedy, at 948; see also, C & K Manufacturing

& Sales Co. v Clayton Yeutter, 749 F. Supp. 8 (D.D.C. 1990).

6. 21 CFR y 174.5.

7. 104 Congressional Record 17,418 (1958).

8. 60 Federal Register 36582 (July 17, 1995).

9. 50 Federal Register 52720 (1993).

10. 21 CFR y 176.260.

11. A. Rulis, ‘‘FDA’s Current Thinking on Recycled Polymers for

Food-Contact Use,’’ presented at the GMA Environmental

Issues Conference on Solid Waste, Washington, DC, May 1,

1991.

12. 42 USC yy6901 et seq.

13. 42 USC yy7401 et seq.

14. 33 USC yy251 et seq.

15. 42 USC yy9601 et seq.

16. California Public Resources Code yy42300-42340.

17. Oregon Revised Statues yy459A.650-459A.665.

18. Wisconsin Statutes Annotated y 100.297.

19. Wisconsin Act 335 (1989).

20. Public Law Number 101-535, now found in 21 USC y 343.

21. See 49 CFR yy172.400-407 for the labeling requirements and

y 173.24 for the packaging requirements.

22. California Business and Professions Code y 17508.5; Burns

Indiana Code Annotated y 24-5-17-1.

23. The Association of National Advertisers, Inc., et al. v Lungren,

Docket No. C-92-0060, United States District Court for the

Northern District of California.

24. New York Environmental Conservation Law y 27-0717; New

Hampshire Revised Statutes Annotated y 149-N: 1.

The nutrition lableing requirement was added to the Federal

Food, Drug and Cosmetic Act by the Nutrition Labeling and

Education Act of 1990.

LAWS AND REGULATIONS, UNITED STATES 645

General References

A. Schmidt, ‘‘Ideas and Reality in Actual Regulatory Experience,’’

Regul. Toxicol. Pharmacol. (Sept. 1988).

J. Heckman, ‘‘Fathoming Food Packaging Regulations,’’ 42 Food

Drug Cosmetic Law J. 38 (Jan. 1987).

Food and Drug Administration, A Food Labeling Guide, Sept.

1994.

LEAK TESTING

GEORGE W. ARNDT,JR.

Schreiber Foods Inc., Green

Bay, Wisconsin

INTRODUCTION

The function of a package is to protect products from

changes brought about by the outside environment. Prior

to the development of packaging, food-borne diseases

caused by pathogenic microorganisms were one of the

most serious problems faced by humans. Microorganisms

excrete enzymes that break down materials releasing

nutrients that they can absorb. Packaging made from

synthetic materials are generally resistant to microbial

enzymes and thus can serve as a barrier preventing the

attach of microbes. During prolonged dry periods, many

microorganisms survive inactively as spores. Bacteria,

yeast, and mold require water to feed, grow, and repro-

duce, so packages need to be maintained in a clean and dry

condition. Packages are inspected before they are ﬁlled for

evidence of water stains, foreign materials, and contam-

ination. Then packages may be washed or blown with

compressed air to remove dust-containing spores. Ther-

mal processing and chemical preservatives kill vegetative

microorganisms and many, but not all, spores. During

ﬁlling and closure, care must be exercised to assure

minimal contamination of package seals that would create

defects. Package defects form a pathway for microbial

penetration and infection. The quality control aspects of

packaging by processors focus upon sanitation and closure

integrity (see also Testing, Permeation and Leakage).

There are many ways to assess the microbial barrier of

packages. Since package styles, closures, and materials

differ widely, there is no universal test method. It is

necessary to evaluate various methods to determine one

that is reliable under the conditions of use.

DESCRIPTIONS OF TEST METHODS FOR PACKAGE

INTEGRITY

Below are brief descriptions of some methods for package

integrity testing. For detailed descriptions, see the Bacter-

iological Analytical Manual, 7th edition, published by the

FDA.

1. Air-leak testing involves pressure decay or mea-

surement of airﬂow rates.

2. Biotesting uses solutions with concentrations

greater than one million nonpathogenic microor-

ganisms per milliliter. Individual packages are

immersed and pressure, vacuum, or mechanical

ﬂexing is applied to distort the package. Alterna-

tively, packages contained within a chamber

may be sprayed with an aerosol mist containing

microorganisms.

3. Burst testing may be used as a dynamic test where

the maximum force required to explode a package

is used as an index of seal strength, or as a static

test where packages are held at a ﬁxed pressure to

determine if the package will maintain pressure for

a speciﬁc period of time.

4. Chemical etching separates or dissolves over-

laying materials to expose the sealant layer of

packages. This is useful for visual examination of

contaminated seals of plastic and paperboard

packages.

5. Compression testing is a burst test using pressure

applied to the outside of a package. Weak packages

will crush or burst, while stronger packages should

not.

6. Distribution testing is a simulation of forces that

are likely to be incurred by packages during sto-

rage and distribution. Tests include vibration, drop

testing, and compression in a laboratory having

controlled temperature and humidity. Simulated

abuse testing is useful for side-by-side comparison

of two or more package designs in order to deter-

mine if one package design is more fragile than

another. Simulation testing is preferred over ship-

ping tests because there are fewer variables and

results from simulated distribution testing are

generally reproducible.

7. Dye testing is used to determine if holes in

packages are present or not present. Water-soluble

dyes should be used with plastics or paperboard

packages, and solvent-based penetrating dyes

should be used with glass or metal packages.

8. Electesting is a nondestructive method for liquid

foods that change viscosity as they spoil. A shock

wave is created by shaking the package. The

amplitude and wavelength of the shock wave is

a characteristic of the viscosity of liquids. When

the device detects a signal response outside the

normal range, the package is rejected. Other tests

may be used to examine rejected packages for

leaks.

9. The electrolytic test uses electricity to determine

whether holes are present in plastic ﬁlms, coatings,

and seals. The detector is an open circuit that uses

electrolyte or metal components of the package to

conduct electricity. Holes are indicated when the

circuit closes activating alarms. Liquid products

containing at least 1% salt, or a solution containing

1% table salt (NaCl) in tap water, may be used to

conduct electricity through very small holes in

packages having plastic layers. Breaks in the

646 LEAK TESTING

coatings of metal cans may be located using this

method. Porous coatings and breaks in coatings

expose metal to the product, and these are the

locations where corrosion can occur.

10. Gas leaks may be detected by mass spectrophot-

ometer or a gas chromatograph. Helium is a useful

tracer gas, because it moves readily through small

holes in packages. Sulfur hexaﬂuoride is inert like

helium and may be used to detect, locate, and

measure small holes in packages in a nondestruc-

tive manner.

11. Incubation is a test that encourages the growth of

microorganisms that are present within packages.

Packages that swell as a result of microbial fer-

mentation of the product may be identiﬁed by

visual inspection. The test can be performed on

large numbers of packages while they are held in a

warm warehouse.

12. Light may be used to spot holes in packages.

Visible light is used to backlight packages and

reveal small holes. Polarized light can reveal areas

within transparent plastic heat seals that are not

fused or have different amorphous or crystaline

compositions. X-rays are used to detect foreign

materials such as stones and glass shards within

sealed packages. Lasers are used to measure

very small differences in package dimensions

that indicate a leak has allowed packages to

change shape. Laser shearography may be used

to measure the effect of stress on packaging

materials.

13. Machine vision may be used to measure critical

dimensions of packages traveling rapidly along

conveyors. Strobe lights stop the action as the video

image is digitized. The picture is compared to

images stored in computer memory. Parallel net-

works enable rapid comparison of images to stan-

dards. Nonconforming packages are sidelined for

inspection by technicians using other tests for

integrity.

14. Eddy-current meters sense the position of metal in

packages. Concave ends indicate retained vacuum.

Flat ends indicate packages have lost vacuum. The

proﬁle of container ends is consistent when the

package, product, and ﬁlling conditions are rigor-

ously controlled. Proximity sensors may also be

used to measure the position of metal components

of packages when a force is applied. Those

packages that respond differently under stress

may be identiﬁed by this method.

15. Seam scopes are large-format low-power micro-

scopes. Mechanical or electronic measuring devices

may be used to measure critical dimensions. Spe-

cialized devices are designed for viewing cross

sections of metal can double seams. The dimen-

sions of very small holes may be measured using a

seam scope as a microscope.

16. Sound is a novel nondestructive testing method.

Rigid packages with internal vacuum may have

ends tight, like a drum. Tapping on a can end

reveals a difference in sound between a normal

can and one that has lost vacuum. Electromagnets

may be used to pull up can ends, which then snap

back. A transducer can register the sound for

analysis. Ultrasonics and laser acoustics may be

used to measure pressure within packages without

contact. Ultrasonic microscopy may be used to

evaluate defects between layers and stress pat-

terns in metals, and plastics.

17. Tensile testing is a term applied to laboratory

methods that stress packages or materials by pull-

ing to create tension. Plastic ends and metal pull

tabs on packages may be peel-tested. Composite

materials may be delaminated and the strength of

adhesion and cohesion measured. Glue bonds may

be evaluated using tensile tests. Pieces of metal or

ﬁlm may be pull-tested to determine elasticity,

stretching, and break strength.

18. Vacuum may be used to test packages in many

ways. Packages dipped in soapy water to coat the

surface before being placed within a vacuum jar

will exhibit bubbles revealing the location and

approximate size of a leak. If the vacuum chamber

is ﬁlled with water and the package held below the

surface, a steady stream of bubbles in the water

may reveal the location of the leak on the package.

Vacuum decay within a closed vessel is a useful

method for measuring small leaks over a period of

time.

19. Visual inspection is the most common method of

package inspection. Holes as small as 100 mm may

be seen with unaided normal vision under ideal

lighting conditions. Unfortunately, inspectors

quickly fatigue and the best visual inspection is

only 85% effective.

SELECTING THE RIGHT TEST METHOD

Some test methods are speciﬁc to materials and others are

speciﬁc to the design of the package closure. No single test

method will work for all applications.

First, begin by collecting as many different package

defects as possible and group them according to their

public health signiﬁcance. A three-class system for pack-

age defects is used in the United States:

1. Critical defect

a. Loss of the microbial barrier

b. Evidence of microbial growth within pack-

age holes, fractures, punctures, swelling and

leakage

2. Major defect

a. Might leak, but has not yet leaked

Testing is

needed to determine whether packages

will leak

c. Weak seals, deformed double seams, deep

scratches, cracks, creases

LEAK TESTING 647