Mosquitos are a pain no matter where you go. In many places in the world, the little pests can spread deadly diseases like malaria. As such, it is extremely important to have a good bug spray on hand.

But some traditional mosquito repellants, like DEET, can have harmful effects on the surrounding environment if not properly contained, and others have raised health concerns. Many people have looked to natural mosquito repellant alternatives, but do they work as well as the old stuff?

According to a press release from New Mexico State University, researchers put 10 commercially available bug sprays to the test. They published their results in the Journal of Insect Science.

Researchers tested Repel 100® Insect Repellent, OFF® Deep Woods Insect Repellent VIII, and Cutter® Skinsations Insect Repellent, which all contain DEET, Cutter® Natural Insect Repellent, EcoSmart® Organic Insect Repellent, Cutter® Lemon Eucalyptus Insect Repellent, and Avon® Skin So Soft Bug Guard, which did not contain DEET, and Avon® Skin So Soft Bath Oil, Victoria’s Secret® Bombshell perfume, and Mosquito Skin Patch®, which used vitamin B1 as the active ingredient.

The sprays were tested against two species of mosquitos known for passing on disease, the yellow fever mosquito and the Asian tiger mosquito. Both of these species can transmit dengue fever, chikungunya, and yellow fever, among other diseases.

According to the study’s authors, “The results of this study show that not all commercially available mosquito repellents are effective in repelling mosquitoes and that efficacy is also dependent on the species of mosquito that is repelled.

“Overall, the results from this study confirm that DEET repellents are the most effective mosquito repellents in the market. Although, based on the results from this study, a lemon-eucalyptus oil containing p-menthane-3,8-diol (PMD) [the active ingredient in Cutter Lemon Eucalyptus Insect Repellent] has similar efficacy to DEET repellents.”