Consumer Reports tests safest, most effective bug sprays

Mosquitoes and ticks spread diseases like West Nile and Lyme. Some are now carrying new diseases such as Chikungunya and Powassan.

Applying a bug repellent is important but most contain harsh chemicals. So Consumer Reports went in search of safer yet still effective alternatives.

Consumer Reports testers reached into a cage filled with 200 hungry mosquitoes.

All the insects are certified-disease free, but they're still ferocious.

Others expose their arms to ticks with one area treated and one untreated. If the repellent is effective, the ticks make a U-turn at the line. A repellent fails if two ticks cross over into the treated area.

Consumer Reports tested 15 different spray-on formulas, some containing the active ingredient deet.

"Deet is an effective repellent but it can sometimes come with some serious side effects like rashes, disorientation and even seizures, so our experts say you should avoid products with more than 30% deet," says Sue Byrne from Consumer Reports.

Consumer Reports also tested several non-deet alternatives. These contain oils like citronella, lemongrass and rosemary.

"We found that the natural and herbal repellents were not very effective at all. But we did find some non-deet products that really work," said Byrne.

One of the best repellents was Repel with Lemon Eucalyptus.

They also top=rated Sawyer Fisherman's Formula. It contains 20% picaridin, which is similar to a compound found in black pepper plants.

Both are safer than deet and Consumer Reports tests found they protect against mosquitoes and ticks for at least seven hours.

Oil of lemon eucalyptus and picaridin are chemically synthesized in a lab.

Make sure to keep lemon eucalyptus away from your eyes because it can cause temporary, severe eye injuries.

Also, don't use it on children under three. A safer choice is picaridin - although it can cause minor irritation to the eyes as well as the skin and lungs.