Roaches are building immunity to bug spray

How cockroaches are becoming invincible

(CNN) - You've probably heard cockroaches can survive a nuclear bomb.

While that’s not scientifically proven, scientists at Purdue University discovered German cockroaches are becoming resistant to insecticides.

Even more horrifying: They can become cross-resistant to chemicals to which they haven’t even been exposed.

They pass those immunities onto their offspring, creating new generations of evolved super-roaches.

Researchers worry this will some day make it difficult - or impossible - to control the bugs with chemicals alone.

They say the best thing to do is combine preventative measures like sanitation and physical methods like traps with insecticides.

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