They are lots of fun, seem harmless and, unlike corrective lenses, are available without a doctor’s prescription. But looks may deceive according to a recent report by Japan’s National Institute of Technology and Evaluation (NITE). Colored contact lenses, says the report, have damaged the eyes of at least 167 people since 2005.

The research results are far from conclusive. Some 13,000 Japanese opticians were surveyed, yet only 145 took the trouble to fill out the questions. Nonetheless, 21 people showed serious damage and 146 showed minor damage due to wearing colored contacts. The reality could be even worse than this research indicates.

NITE also found some serious quality problems among colored contact lenses in regards to thickness, diameter and curvature.

As a result, the Japanese Health, Labor and Welfare Ministry plans to place colored contact lenses under similar regulations used for corrective lenses. According to the new regulations, permission would be required for shops selling colored contact lenses, and customers would have to be educated about the risks in wearing these lenses. It is not yet known when these regulations will become activated.

See some photos of people with colored contact lenses.