A reader responds to a recent column on peanut allergies: 

Q: My children, 3 years and 21 months, both have a severe peanut allergy as well as allergies to tree nuts.

I feel it is important to point out an error in the column, which stated, “food labels should specify whether a food contains peanuts or peanut products, and whether it has been processed in a factory where peanuts may be present.”

Unfortunately, the Food Allergen Labeling and Consumer Protection Act of 2004 (FALCPA) does not require the declaration of allergenic ingredients introduced through cross-contact.

I certainly wish it did. I cannot begin to tell you the countless hours I have spent on the phone with various manufacturers trying to determine the level of risk posed through potential cross-contact. I found that a spaghetti sauce we had been using is made in a facility that also produces peanut butter. That was not on the label, and was only uncovered after contacting the manufacturer.

Many companies have recently chosen to include “may contain” labels, but it is not required by FALCPA, and is also the exception from what I have seen. — Via email

A: Thank you for your informative response. Food labels should (as in “ought to”) specify whether foods have been processed in facilities where any of the major food allergens are present. But they are not required to do so.

The Food Allergen and Labeling Consumer Protection Act requires that labels specify whether any of the major food allergens are ingredients, but not whether they may have inadvertently come into contact with the food you bought.

Cross-contact can occur during harvesting and storage or processing and packing. Bits of peanut butter or peanut flour may contaminate equipment also used for preparing other foods.

Peanuts are used in many processed foods and so may be found in many food-processing plants. Small amounts may be present in foods where peanuts are not listed as an ingredient.

For some highly sensitive children and adults, a tiny bit can produce a big — even potentially fatal — reaction.

Many parents and teachers have worried that these allergic reactions could be set off simply by being exposed to peanut butter “fumes” or by absorbing peanut butter through the skin. This worry has caused havoc in schools where allergic children may be exposed to other children’s peanut-butter sandwiches.

But peanut proteins that set off allergic responses are not present in peanut-butter vapors, and they are unlikely to be absorbed through the skin into the bloodstream.

But hand-to-mouth exposure remains a risk and a concern for schools, especially preschools.

What are the solutions for children with peanut allergies?

At many schools, no-food-sharing policies have become a necessity. An “allergen-aware” table for children with peanut allergies and friends who avoid peanuts too can be reassuring without being ostracizing.

Cross-contact during food processing is a tougher issue. It’s commendable that you called up the manufacturers. Some companies label their foods with cross-contact information. A few go to the trouble to process their foods in peanut-free facilities. The most reliable solution may be to buy as few processed and packaged foods as possible.

For more information, visit www.fda.gov/ForConsumers/ConsumerUpdates/ucm089307.htm.

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