Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Do NOT purchase this item...

Ozone is a severe pollutant. Ozone in the upper atmosphere is naturally occurring and environmentally beneficial; it shields the Earth's surface from the sun's harmful ultraviolet light. It is important not to confuse this with the fact that ozone in the Earth's lower atmosphere, where we live and breathe, is a harmful air pollutant. Ground-level ozone is regulated by Federal and State Clean Air legislation.Exposure to ozone can irritate the eyes, nose, throat, and lungs. It's especially harmful for those with asthma and studies show that it can cause serious and permanent damage in the lungs.If you're not convinced, please read more at the EPA's website.