There is actually no scientific evidence to prove the age-old claim that petroleum jelly boosts lash growth, but countless people claim to have had success with it. Many people believe the lash-growth effect is due to the petroleum jelly providing a protective barrier, which can make your lashes stronger and thus less likely to break before reaching their full length potential. Petroleum jelly (also known as petrolatum) is generally considered safe, however, concerns have recently been raised about the risks of contamination from cancer-causing chemicals that are found in the oil from which the petrolatum is sourced.  Some people avoid petrolatum not out of health concerns, but out of ethical ones, as it is sourced from oil, which is a non-renewable resource.  Allergic reactions to petroleum jelly are rare but possible, so use with caution. In addition, as petroleum jelly is greasy, there is also the risk that applying it to your lashes could cause the pores on your eyelids and lash lines to become clogged, causing irritation or styes. You should be able to find both of these things at drugstores, beauty supply shops, and dollar stores.  If you’d prefer a wand but don’t want to buy one, you can even go to a store that sells makeup and request one of the disposable wands used for testing out products and applying makeup during in-store makeovers. If you get a disposable wand, be sure to clean it after each use with a gentle cleanser (baby shampoo will work) and lukewarm warm water. Use a gentle, unscented cleanser to wash your eyelids and lashes, being sure not to rub them or apply too much pressure. This will ensure that they are free of debris such as residual makeup. Use a gentle cleanser to wash the petroleum jelly completely off your lashes and lids. You need to give your eyelids and lashes a break, otherwise you’ll risk getting clogged pores, which could make lashes fall out or at least stop them from growing.  If you’re wearing it in place of mascara, don’t wear it at night. If you wear it at night,...

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Write a summary of the previous text in Vietnamese:
Biết vì sao sáp dầu có hiệu quả trên lông mi. Biết về các rủi ro. Mua cọ chải mascara hoặc tăm bông. Rửa mí mắt và lông mi. Đảm bảo rửa thật sạch mí mắt và lông mi. Không thoa sáp dầu suốt ngày. Chờ đợi sự khác biệt trong 2-4 tuần.