In vitro effects of preservatives in nasal sprays on human nasal epithelial cells.
BACKGROUND
The preservatives benzalkonium chloride and potassium sorbate are widely used in nasal drops and sprays. Recently, side effects resulting from mucosal damage caused by benzalkonium chloride and potassium sorbate were reported.


METHODS
We investigated the toxicity of benzalkonium chloride and potassium sorbate on human nasal epithelial cells in vitro. Using primary human nasal epithelial cells, different concentrations of benzalkonium chloride, potassium sorbate, or phosphate-buffered saline (PBS; control group) solutions were cocultured with nasal epithelial cells for 15 minutes. Then, the viability of the cells and the cell morphology were assessed.


RESULTS
Nasal epithelial cells were more severely damaged with use of clinical preparations or higher concentrations of benzalkonium chloride than in the control group. In addition, nasal epithelial cell membrane lysis was seen on electronic microscopy in the benzalkonium chloride groups. In contrast, there was no significant cell damage seen in the potassium sorbate groups compared with the control group, even with higher concentrations than clinically used.


CONCLUSIONS
Potassium sorbate appears to be a relatively safer preservative than benzalkonium chloride for use in nasal sprays and drops in vitro study.
Ho
Ching-Yin
CY
Department of Otolaryngology, Veterans General Hospital-Taipei and National Yang-Ming University, Taipei, Taiwan.
Wu
Meng-Chuan
MC
Lan
Ming-Ying
MY
Tan
Ching-Ting
CT
Yang
An-Hang
AH
D001548:Benzalkonium Compounds / Q000633:toxicity*; D006801:Humans; D066298:In Vitro Techniques; D009297:Nasal Mucosa / Q000187:drug effects*; D011310:Preservatives, Pharmaceutical / Q000633:toxicity*; D013011:Sorbic Acid / Q000633:toxicity*
D001548:Benzalkonium Compounds; D011310:Preservatives, Pharmaceutical; D013011:Sorbic Acid