After a sampling survey of hair care products, China has ordered that eight hair gels be banned. The country’s Ministry of Health has also told consumers to stop using the products as well.

The sample revealed that the hair gels were found to contain high levels of methanol. Methanol is a type of alcohol that is not safe for human consumption. Repeated exposure to methanol can cause a number of health problems and result in severe headaches, optic nerve damage and diarrhea.

The companies that manufacture the products have now been blacklisted. The eight companies are located in Guangzhou and Tianjin Municipality.