With the crazy smog going on in China, businessmen are now ready to grope for your wallet. "Smog economy" is stimulating a shopping _ on certain products against the terrible weather. Now let's see what we have on the list to help us through the crisis. 1. Masks Well, I would say you had better stay indoors to save your lives. PM 2.5 just surged up to 750 in Beijing recently. 3M just sold 220,000 masks of a kind. No.1 best-selling products! 2. Air purifiers This kind of products is rarely seen in Chinese households in the past. They have become a necessity now. I do like these little gadgets, but they are just too expensive. 3. Oxygen inhalers I didn't realize oxygen inhalers also get a cut in the smog economy. As a matter of fact, your oxygen uptake has nothing to with relieving   the impact of smog. It might even lead to oxygen poisoning when you inhale too much oxygen. So don't get greedy. 4. Salt lamps Compared to oxygen inhalers, salt lamps are even worse. Some stores are selling the products at several hundred yuan, saying that they can release negative ions , reduce radiation levels and purify the air. The lamps mainly contain sodium chloride. The boiling point of sodium is about 800 degrees centigrade and that of candle is 500. So how on earth can negative ions be released at only 500 degrees? 5. Plants that absorb smog Yeah, right. Plants Vs Smog. It is scientifically justified   that some plants do absorb pollutants from the air. Money plants and calla lilies are among the best-sellers in the market. Even if they don't work, it's good to have some plants in the house anyway. How many ways does the author think are useful?
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