More fear than actual peanut dust swirls through the air concerning airborne peanut reactions. As I explain in earlier article, many people think that just sitting in a chair next to a peanut butter sandwich can cause a severe reaction. Although airborne peanut reactions are possible, the risk is actually lower than you may think.

Concern over peanut exposure is justified, because peanut is so pervasive, but only by establishing a realistic risk assessment can you identify the true risks and let down your guard in low-risk situations. The truth is that an airborne peanut reaction from peanut butter, candy bars, and even peanut butter crackers is very unlikely.

Here’s why:

• Peanut butter and candy bars tend to bind the peanut dust with other stuff like chocolate or caramel, so rarely does a sufficient amount of peanut protein escape into the surrounding air to cause a reaction.

• Even though you can smell the peanut from these foods, evidence shows that the odor emanating from peanut butter or candy bars does not contain the protein that could cause a reaction when someone handles or eats these foods.

You could experience an airborne peanut reaction if the peanut eater was in your face, talking and laughing, and essentially spraying small droplets of peanut at you. Aside from this kind of situation, however, the risk is nearly negligible and identifying cases of peanut reactions from this kind of exposure is very difficult.

Is your child’s lunchroom permeated with peanut? Does your child need to sit at a peanut-free table? Should the entire school ban peanuts of any kind from the premises? These are all valid questions, but you can safely say that we have no universally correct answers to these questions.

Parents, students, and school administrators often hold opposing views. Even different doctors can be in total disagreement. I’m quite certain that prior to 1990, the peanut-free table was unheard of. Considering peanut-free tables since then has often been thought to be borderline un-American.

Now peanut-free tables are the norm in most schools, and some schools ban peanut products altogether. So who’s right? Following is the approach I recommend:

• Designate peanut-free zones up to the third or fourth grade. Preschool-age children are much more likely to be tempted to share food, to have lots of peanut on their hands, and have difficulty keeping their hands to themselves. As children grow older, these risks lessen.

• Phase out peanut-free zones in higher grades. I am not convinced that peanut-free zones provide any additional safety for older students. In fact, I now write many more letters to get kids out of peanut-free tables than I do to get kids seated at peanut-free tables.

This typically occurs in older children who have become fed up with being isolated at a peanutfree table and whose parents accept that the risk of eating at regular table is incredibly small.

My recommendations may seem too safe for some and too risky for others. You, your child, and your school must work together to establish an acceptable level of safety that keeps kids safe without emotionally isolating them or preventing them from fully experiencing their school years.

Among the places where airborne reactions do occur are bars and restaurants where peanuts are being served as a snack. In these settings, peanuts are usually served in the shell, and the process of cracking shells leads to small amounts of protein becoming airborne, sometimes in high enough concentrations to trigger a reaction.

This may be a further exacerbated when the peanut shells accumulate on the floor and patrons and servers kick up the dust, especially in an enclosed area. When you’re allergic to peanuts, you’re best bet is to avoid restaurants and bars that serve peanuts in their shells, even if that means leaving your friends behind at the local pub.

The worst reactions I’ve seen in these situations occur when the airborne peanut protein is combined with large doses of alcohol and denial, so that the reaction gets out of hand before the person experiencing the reaction has a chance (or inclination) to leave. Otherwise, simply leaving the area usually leads to a rapid cessation of symptoms, especially when combined with medication.

What would a baseball game be without shelled peanuts? For someone who suffers from peanut allergy, the game would be a heck of a lot more enjoyable. By the third or fourth inning, the stadium floor is carpeted in peanut shells, and people with peanut allergies often begin to spend more time looking at the exit signs than at the scoreboard.

In the open-air venue of a baseball field, however, the risk of an airborne peanut reaction is relatively low. In fact, most people with peanut allergy experience no symptoms in an outdoor stadium, even when surrounded by a crowd of peanut shelling fans.

So, can you safely take Junior to see his favorite baseball team in action? Well, that depends on whether Junior is old enough to sit in his seat and enjoy the game. Taking young children who are prone to picking up things off the ground, including every peanut shell in sight, is just not worth it.

Unlike peanuts, which are really legumes (in the bean family), tree nuts are really nuts. Tree nuts include almonds, Brazil nuts, cashews, hazel nuts, hickory nuts, macadamia nuts, pecans, pine nuts, pistachios, and walnuts. As opposed to peanuts, which grow in the ground, tree nuts, as their name implies, grow on trees.

In food allergy circles, most people lump together peanuts and tree nuts. Botanically speaking, associating peanuts with tree nuts is absurd. Allergically speaking, however, the association makes a lot of sense. Following is a list of similarities:

• Like peanuts, tree nuts can cause severe allergic reactions.
• Tree nuts are capable of causing severe reactions with minute exposures.
• Peanuts and tree nuts tend to travel in the same circles — baked goods, ethnic foods, candies, and ice creams are the most common causes of accidental tree nut exposures.
• Tree nut oils and extracts all contain the allergenic proteins, so you must avoid the oils and extracts, too.

In studies of fatal food allergic reactions, tree nuts rank second only to peanuts. Even though tree nuts and peanuts are botanically unrelated, people with tree nut allergy often have peanut allergy, and vice versa. Several studies show that 30 to 40 percent of people with peanut allergy also develop tree nut allergy.

We allergists used to struggle to explain the link between peanut and tree allergy, and we thought it was most likely due to the fact that peanuts and tree nuts are both just very potent allergens. New research, however, has uncovered actual structural similarities between peanut protein and many of the tree nut proteins.

At this point, you’re probably wondering, “If I have a peanut allergy, should I avoid tree nuts?” The short answer is “Yes.” For a longer answer, discuss with your doctor the pros and cons of avoiding tree nuts. In my clinic, we recommend that patients with peanut allergy avoid tree nuts for the following three reasons:

• Peanuts and tree nuts are all too often processed together or at least near enough to one another to pose sufficient risk.

• Manufacturers often use peanuts as a substitute for tree nuts, because peanuts are cheaper.

• In young children with peanut allergy, staying away from tree nuts may help prevent the child from developing a tree nut allergy.

For those with a tree nut allergy, many forms of peanut can be safe, especially major brand peanut butter and some candies. Be careful though; dry roasted peanuts are often tree-nut contaminated, and a gourmet peanut butter may have shared equipment with almond or cashew butter.