Children in a private kindergarten in Hangzhou, Zhejiang province, were found to have problems with their fingernails, but the exact cause or reasons for the defects are still unclear, according to Hangzhou Daily.

The kindergarten confirmed 17 children had problems with their fingernails and the parents of 12 children had withdrawn them from the kindergarten.

Parents claimed more than 50 children suffered from nail problems and said that indoor decorations may be to blame.

The kindergarten opened in June and indoor decorations were completed in Sept 2012.

Reports from the local authority showed that indoor air quality met national standards.

Doctors from local hospitals were examining the children to find the cause.?

Contact the writer at tangzhihao@chinadaily.com.cn