1: "What is Christmas tree syndrome?"

2: "Pine, mold, and dust can trigger it."

3: "Runny nose? Check your Christmas tree."

4: "Dry air irritates nasal passages."

5: "Indoor allergens spike in winter."

6: "Pets can worsen winter allergies."

7: "Humidifiers help combat dry air."

8: "Regularly clean air filters."

9: "Consult a doctor for severe symptoms."