Your cell phone can be detrimental to your ocular health—and not just because of the blue light exposure and excessive near vision tasks. A new study shows that the phones of contact lens–wearing university students are highly contaminated with pathogenic bacteria and may act as carriers, eventually infecting eyes.

The Jordan-based investigators swabbed 63 patients’ conjunctivas, mobile phones and contact lens storage cases—a total of 189 swabs.

Altogether, the team found nine bacterial species: Staphylococcus aureus, Streptococcus pyogenes, Enterococcus faecalis, Shigella dysentery, Pseudomonas aeruginosa, Proteus mirabilis, Citrobacter spp., Klebsiella pneumoniae and Escherichia coli.

Nine of the mobile phones (26%) and seven (21%) conjunctival samples were contaminated with five different bacterial species. While the researchers suspect the phones act as a carrier of the bacteria, the highest level of contamination was detected in the contact lens storage cases. Eighteen (52%) bacterial isolates were detected in cases.