"While consumers are aware that bug bites may affect their health, many people are also concerned about the possible drawbacks of common repellents such as DEET," David Andrews, senior scientist at EWG, said in a statement. "It is hard to find objective scientific evaluations of the many different repellents on the market."
Andrews said the researchers at the EWG found picaridin, IR3535, DEET and oil of lemon eucalyptus, or its synthetic derivative PMD, were the most effective and safest, CBS News reported
Different bug repellents might be better than the others depending on the situation, but these four ingredients provided both the longest protection with the fewest health concerns.
Some might be surprised to see DEET listed because it was linked to nervous system impairment, Andrews said, but it requires high doses to cause a reaction, and there is very little scientific evidence to link health problems with limited use, CBS News said.
The EWG report also said bug repellents of any kind should not be used on children age 6 months or younger.
Outdoor "fogger" insecticides, candles and aerosol sprays in pressurized containers may release toxic fumes or ingredients that could make people sick, the report said.
Repellent mixed with sunscreen may overexpose people to repellents, because sunscreen needs to be reapplied every 2 hours or sooner, and bug zappers and treated wristbands simply don't work, the EWG report said.