
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?”
https://twitter.com/am8_01/status/739885037567410177▼ “If you keep spraying until the cockroach stops moving, you’ll be the one dying from overkill.”
https://twitter.com/O9nishi21stst6/status/743733316419870720▼ “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.”
https://twitter.com/asuka_0114/status/743401952646569986It 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

Japan’s “strongest roach killer” is frighteningly effective… We mean FRIGHTENINGLY effective
Japan approves foreign resident visa renewal fee increases of up to 967 percent, starts soon
Japan tripled its departure tax to fund tourism but is using the money on cherry blossoms and bears
Tokaido Lumière Express: Stay overnight inside the Shinkansen from Osaka to Tokyo
McDonald’s Japan reveals exclusive new Tsukimi moon viewing collection for 2026
Godiva Japan hops into tsukimi season with bunny and moon-themed chocolate assortments
Ministop brings bulked up Okinawan-style rice balls to mainland Japan for one week only
Nike x One Piece collection brings Devil Fruits to sneakers and streetwear in Japan
Nephew of Studio Ghibli director Hayao Miyazaki serves up Totoro Shaved Ice in Tokyo
Domino’s puts a new spin on moon viewing with Tsukimi dango-inspired tarts in Japan
Starbucks Japan adds new Customisation Bar to stores, with free ways to hack your food and drink orders
7-year-old boy left behind on Mt. Fuji by his own dad
Sushi Bus: Japan’s first conveyor-belt bus lets you eat sushi while sightseeing around Tokyo
Studio Ghibli unveils new interactive stationery dioramas that bring anime movies to life on your desk
Anime fans can now wear a Seiko watch inspired by Japan’s One Piece Shinkansen
7-Eleven Japan brings back best-selling flat croissant that became a hit on social media
Studio Ghibli composer Jo Hisaishi just set three Guinness Records
Foreign hiker on Mt. Fuji loses consciousness and dies, becoming climbing season’s second fatality
We recommend not buying one pack of Japan’s new convenience store corn soup-flavor fried chicken
12-year-old British girl who went missing in Tokyo found safe after visiting anime sites around Yokohama
Air-conditioned dress shirts arrive in Japan to save working professionals from sweltering heat
Pokémon Center Online designates first Pokémon items that will require Japanese ID card to buy
Japanese toilet aims to attract foreign tourists but not everybody is happy about it
Tokyo’s newest viral dessert is like a Japanese parfait inside a bread bun [Taste test]
New Japanese vending machine at Shinkansen station sells cups of ice on platform
Study finds hundreds of people in Indonesia legally named after Naruto, Inuyasha, other anime stars
Japanese vending machine sells freshly squeezed lemon juice with a futuristic light show
Japan announces sudden 400-percent increase in visa fees for foreigners entering the country
Japan’s human washing machines will go on sale to general public, demos to be held in Tokyo
Studio Ghibli has a new anime out, and there’s only one place in the world where you can see it
Starbucks Japan releases new drinkware and goods for Valentine’s Day
Starbucks Japan releases new sakura goods and drinkware for cherry blossom season 2026
Japan’s newest Shinkansen has no seats…or passengers [Video]
Tokyo subway installing new ticket gates that don’t accept payment through Suica or other IC cards
Japanese ninja certification exam attracts 131 candidates from Japan and abroad
Salomon releases Japan-exclusive Mt. Fuji hiking gear that doubles as an amazing souvenir
Put sesame oil in your coffee? Japanese maker says it’s the best way to start your day【Taste test】