Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Ruined my home with charcoal dust!

I purchased this "air purifier" from a local retailer with the thought it would clean the air in my home. After the first week of using the product I began to notice a fine black dust around the rooms I was using it in. The BLACK DUST problem became worse and as it turns out it was from the carbon(charcoal) filter in this air purifier. The unit blows (exhaust) air straight up--about like a box fan on "High" setting. It does not clean off very easy as the dust particles are so fine and now I must repaint the rooms I used this in. I am returning this to the retailer tomorrow!