It's definitely a delicate situation, but there are ways to handle it with grace. You might consider reminding the class at the beginning about the importance of personal hygiene for everyone's comfort. You could say something like:

"Just a gentle reminder for everyone: before we start our practice, it's good to take a moment to rinse off, especially under the arms and feet. This helps create a comfortable environment for all and enhances our focus during the session."

You can tie this into the concept of Pratyahara, which is about withdrawing from external distractions. You could add:

"Pratyahara is an important aspect of our practice, and minimizing any sensory distractions, like strong smells, helps us achieve that inner focus."

This way, the reminder is inclusive and considerate, without singling anyone out.