Is my breast milk safe?

fuck🖕🖕🖕🖕🖕🖕

So I'm out and about my daughter is breast fed. I took 12oz of breast milk with us...well my daughter gets hungry as I'm pouring a bottle for her I ask my 5 yr son to hold the cap to the storage bottle. When my son hands it back he licks the cap. Is the breast milk now contaminated?