Good News! Nature’s most unsettling house guest is getting stronger.

We’re getting deep into cockroach season here in Japan, where those nauseating little balls of disgust wake up and greet us in our homes with surprise visits. However, this year, there seems to have been an increase in people struggling more than usual to kill the beasts with sprays.

“So, there was a freaking huge cockroach but I didn’t have a GokiJet. I spent three hours fighting it with other, weaker spray, but what do you think?”

“If you keep spraying until the cockroach stops moving, you’ll be the one dying from overkill.”

“Cockroach VS Three Women: In the end Asuka killed it but it took an hour. It flew and we screamed. After flying, we kept spraying it until after it died. The spray made it jump and we thought it was alive and we screamed. We’re tired.”

It was enough to cause NHK News Web to look into what was happening with Japan’s cockroaches. They first asked insecticide manufacturers who constantly investigate the effects of a variety of substances on pests in an effort to improve their products.

While everyone assured that their sprays are still effective, a disturbing trend has been seen with certain German cockroaches (Blattella germanica). In collected samples found around Tokyo it would seem these roaches have an increasing tolerance to the neurotoxin permethrin, which is the most widely used pesticide in the world.

Some German cockroaches were found to be up to 200 times stronger against permethrin than average ones. Since roach sprays are combinations of ingredients, they’ll still work but this might explain why some people have to continuously spray a roach before they die…aside from their own terror that is.

▼ Many online see this as the beginning of Terra Formars, a sci-fi series in which highly evolved roaches set out to slaughter humans on Mars.

And their tolerance is only going to better over time. As roach expert Hideaki Tsuji told NHK, the German cockroach’s fast generational turnover allows them to evolve quickly. Thanks to natural selection, stronger roaches will survive until conventional sprays become useless in the not too distant future.

Luckily, cockroaches so far haven’t been able to adapt to my own personal insecticide: a spare block of wood by my front door that I whack them with. But when they do, god help us all…

Source: NHK News Web via Hachima Kiko (Japanese)
Top Image: Amazon 1, 2
Video: YouTube/Epicblargman