While a “functional barrier” may effectively prevent migration of uncleared substances into food from the outside surface of packaging,

what are the FDA considerations when there is potential transfer into food via set-off to the food contact side in the reel or stack of printed material? Is there a certain "migration limit" for substances not cleared under FDA CFR 21 and for which no toxicological data is available?

The migration limit requirements for FDA cleared materials are specified in each corresponding 21 CFR listing and in the individual FCNs. However, the "functional barrier" exemption applies only to the design of the food package, with the reasonable expectation that the barrier prevents migration of substances from the outside of the barrier into food.
However, packaging materials often are rolled up or stacked one inside the other, so that there can be offset between a printed/coated side of the packaging material and the other, food contact side. If the migrating substance is cleared under an existing FDA regulation, then the specified migration limit must be respected. This can be confirmed by appropriate testing (see below).
If the front-to-back migrating substance is not cleared under an existing FDA regulation, and if it is not a carcinogen or reproductive toxin or other problematic substance, then it still can be used in food packaging if it can be shown by test data or calculations that it would be present "in the diet" at a concentration of 0.5 ppb or less. Below this de minimis concentration the substance is not considered to be a food additive under the "threshold of regulation" principle. Calculations to determine the concentration in the diet can be found in section IIE of FDA Guidance for Industry: Preparation of Premarket Submissions for Food Contact Substances: Chemistry Recommendations at http://www.fda.gov/Food/GuidanceComplianceRegulatoryInformation/GuidanceDocuments/FoodIngredientsandPackaging/ucm081818.htm. In general, if the concentration of the migrating uncleared substance in food is below 50 ppb, then the eventual concentration in the diet normally will be less than 0.5 ppb.
Highly cross-linked coatings over printed surfaces can act to minimize such front-to-back migration. If a coating is not practical, then non-FDA inks should be UV/EB cured or heat set to "lock in" any potentially migrating substances.
In any case, if a printer is concerned about possible front-to-back migration, then appropriate testing of the food contact surface should be conducted to identify and quantify potential migrating substances. Test methods must be validated to assure that they are capable of detecting the target substance at the required low level of migration.

Source: Ron Golden, rgolden@focalconsulting.com

Note on skin irritation

The acrylates used in UV curing formulations may cause skin irritation, so nitrile gloves and protective clothing should be worn at all times when handling these materials. Simple latex gloves are not sufficient. Barrier creams may be applied before working with acrylates to facilitate complete skin cleansing during wash-up.
If unexpected or accidental contact occurs, the UV curing materials should be washed off of skin with soap and water when the skin contamination is discovered. Contaminated clothing should be laundered or discarded. The slowness for symptoms to develop and the relative mildness of the symptoms in most people can cause many to ignore or delay cleanup. In some cases, repeated exposure caused by poor hygiene practices ultimately can result in enhanced sensitivity to the chemistry.
In very rare cases for hyper-sensitized people, preventing direct contact with the liquid formulation no longer is sufficient to prevent the irritation reaction, and the only remedy may be to permanently remove them from areas where acrylates are in use. The best way to test whether someone is hyper-sensitized is to determine if they have a reaction after a few minutes just by walking into the UV/EB production area, even without handling or contact with acylate materials. If there is no reaction from just being present in the work area, protective equipment and more attention to good hygiene practices should be adequate to prevent irritation symptoms.

Congratulations to the Winners...

The RadTech Emerging Technology Awards. Awards will be presented Tuesday May 25, at the events special awards dinner (www.radtech2010.com):

Gillette-Procter & Gamble (P&G)
Innovative UV Curable Sustainable Packaging Solution Replacing Conventional Foil Lamination and Hot Foil Stamping

ReflecTech, Inc.:
UV-curable hardcoat to improve the abrasion resistance of reflective films used in concentrated solar energy systems.

Johnson County School District 1, Buffalo WY
Field Applied UV-Cured Gym Floor Finish.

Cambrios
UV curable coated nanostructured system as an alternative to ITO conductive films in flexible electronic applications

Are nitrile gloves adequate protection from exposure to UV light in the workplace?

With normal shielding of UV curing equipment, workers are exposed only to reflections of UV light, and normal work clothing provides adequate attenuation of UV radiation in the workplace. Most polymers and pigments are strong absorbers of UV radiation, so even a thin layer of pigmented nitrile rubber is very effective protection from UV light, which does not have much penetrating power. Even unpigmented gloves should provide adequate protection from reflected UV light.
Of course, worker training to use the correct protective equipment and to recognize the symptoms of over-exposure is essential. The symptoms of over-exposure to UV light are the same as sunburn, so workers will notice very quickly if their protective gloves or clothing are inadequate for conditions, and you can enhance the protection if necessary.

UV, EB, CO2

RadTech is increasingly being asked about the role UV and EB technology may play in efforts to develop cleaner technologies that reduce greenhouse gas emissions.
In 2005, the RadTech Technical Committee weighed-in on the issue with the following observations:

- UV/EB technology can be a “one-stop shop” for businesses to keep up with state, national and international requirements. Adoption of UV/EB processes can assist compliance with U.S. regulations as well as with those that businesses face abroad.
- The EPA and local air districts agree that UV/EB is good news for the environment. The overwhelming majority of UV/EB coatings, inks and adhesives contain little or no volatile solvent. Solvents, when incinerated, generate additional greenhouse gases from combustion.
- Emissions of VOCs, which are tropospheric (ground-level) ozone precursors, can be nearly eliminated with the use of UV/EB technology. Ground-level ozone is estimated by the EPA to be the third largest contributor to climate change.
- As one example of the savings that has already been achieved through the use of the technology, a major industry study of a UV process line found an over 65% reduction in greenhouse gas emissions. The study compared UV curing to a water-borne coating line equipped with incineration. There was also a documented 80% reduction in the total amount of energy used by the facility. As a result of these energy efficiency advances, the study noted that the energy savings offered by UV/EB technology translated into 62 billion BTU/year for the company, and achieved as much as a 55% reduction in capital and installation costs over thermal curing. While the benefits of UV/EB technology may vary depending on the particular facility and the intended use of the technology, this study and the experience of this industry demonstrate that EB and UV curing may be used to achieve meaningful voluntary reductions of greenhouse gas emissions.
- The use of UV/EB-curing processes can inherently reduce greenhouse gas emissions by reducing reliance on the burning of fossil fuels. UV/EB technology is highly energy efficient, utilizing equipment that is relatively cooler and smaller than that used for other drying methods. In addition, it can cure materials at or near room temperature in a matter of seconds or less. For these reasons, the total energy used in UV/EB-curing processes can be significantly lower than the energy needed for thermal drying, resulting in energy savings and reduced reliance on the burning of fossil fuels that contribute to greenhouse gas emissions.

We hope you may share your further information and data? For example, in one illustration offered by a RadTech member: Since much less material is used to coat a given substrate for many UV/EB applications, far less chemistry is trucked to manufacturing facilities--offering substantial savings on the energy used and emissions generated for transportation.

What are your thoughts?

Cross posted:
RadTech LinkedIn— http://www.linkedin.com/groups?gid=1799180&trk=hb_side_g
RadTech Blog— http://www.uveb.blogspot.com/

NYSERDA announces the upcoming release of Program Opportunity Notice (PON) 1641

Congrats to the UV & EB industries for NYSERDA support of our technology. Details will be released at uv.eb EAST (www.uvebeast.com). NYSERDA will have reps at the event to provide details...
NYSERDA announces the upcoming release of Program Opportunity Notice (PON) 1641: Ultraviolet Light (UV) and Electron Beam (EB) Process Innovation and Market Transformation. The solicitation will provide incentives for New York State industrial sites to adopt innovative UV and/or EB processes within their manufacturing process, or for New York State technology developers to produce an innovative UV/EB product, process or service that will provide an energy benefit to end users. The release of this solicitation will coincide with NYSERDA’s jointly sponsored conference with RadTech, entitled UV/EB East, which will be held at the Niagara Falls Conference Center, Oct. 20-21, 2009.
“PON 1641 demonstrates NYSERDA’s commitment to support the deployment of environmentally friendly technologies and will provide up to $2 million for research and demonstration projects within New York State,” said Francis J. Murray, Jr., NYSERDA President and CEO. “The increased adoption of ultraviolet light and electron beam curing technologies complements the vision of Governor Paterson’s energy efficiency agenda and will enable New York State manufacturers to remain competitive and create clean energy jobs for the future.”
NYSERDA has provided incentives for a number of notable UV and EB projects through funding opportunities that sought proposals covering a wide array of technologies. PON 1641 is NYSERDA’s first targeted UV/EB solicitation.

We are formulating inks for a label on the outside of a plastic cup.

The label reaches all the way to the top lip of the cup, so it is likely that the person drinking from the cup will physically have their mouth in contact with the label and will ingest some of the liquid contents that have come into contact with the outside of the printed label. Is this a direct food contact application, and must the printing on the label be cleared under the FDA regulations for direct food contact?

There are two possible answers, depending on the intended use for the cup.

1. If the labeled cup is used as food or beverage packaging, it is reasonable to expect that substances that have the potential to migrate from the label will be ingested by mouth contact along with the food, and any inks, coatings or adhesives used to manufacture the label must be FDA compliant. They must meet any applicable requirements for composition and extraction testing, or it must be shown that any migration of uncleared component substances is below the level of regulatory concern.
2. If the labeled cup is intended for use solely as a household container, it may fall under the “FDA housewares” exemption, which holds that materials used to manufacture empty containers, dinnerware, eating utensils or appliances sold to consumers for home use do not require food additives clearance.

In both cases, it is advisable to obtain legal confirmation that the inks, coatings or adhesives used to manufacture the label and the finished article comply with all regulations that apply for the intended use.