Why does Roach Spray kill Roaches but is not harmful to humans?

Question

Being that the Cockroach is one of the hardiest creatures. They can resist Radiation at 15 times the level a human can tolerate, they can live headless for a week and can hold their breath for 45 minutes, they can go without food for five weeks and still survive-so what exactly is in roach spray and shouldn't that be extremely poisonous to us?

Answer 1

Actually, the poison in the roach spray IS harmful to humans, but our internal chemistry is different, so it takes a MUCH larger dose to kill us than a cockroach.

Most roach sprays use carbamate insecticides. They are cholinesterase inhibitors -- the action is very similar to the chemical nerve agents used by Saddam against the Iranians (1980-88), and that Aum Shinri-kyo used in the Tokyo subway attack (1995). They interfere with the nervous system by blocking the action of acetylcholinesterase -- overstimulating and preventing the muscles from relaxing.

Carbamate insecticides are toxic to humans at the following LD50s (LD50 = Lethal dose to 50% of the exposed population):

Aldicarb -- 2.5 mg/kg body weight (skin absorption)
Carbofuran -- 120 mg/kg
Aldoxycarb -- 1000 mg/kg
Carbaryl -- 4000 mg/kg

Compare those toxicities to these for the nerve agents:

Tabun (the first nerve agent, invented by the Germans before WW2) -- 0.3 mg/kg
Sarin (the stuff used by Aum Shiri-kyo) -- 0.01 mg/kg
Soman -- 0.02 mg/kg
VX -- 0.5 mg/kg

Then we'll compare these to some REALLY toxic materials -- biotoxins:

Saxitoxin (a shellfish toxin) -- .01 mg/kg
Ricin (from Castor beans) -- .000001 mg/kg
Botulism toxin -- .0000003 mg/kg

See the link below for more details on tthe carbamates.

Answer 2

Some chemicals affect different animals in different ways.

For example, PCP (angel dust) is a highly addictive drug for humans, and someone who's on it can go berzerk, the cops come in, hit him with a tazer several times, and he'll keep fighting.
But the drug has a legit use as a horse tranquilizer.

Now imagine the resources of a major R&D operation being directed to finding the right chemical that kills roaches but is safe for humans.

Answer 3

Actually it is toxic to humans, but you have to take into account the relative sizes. If you hit a human with the same amont in relation to their size, the perosn would drop dead faster than the roaches.

It's just size of critter and amount. It's all poison, both to us and the bug.

Answer 4

Boric acid , it is very effective when used properly for killing
cockroaches and most other insects.

More information at http://tinyurl.com/ofxkk

Answer 5

It is harmful to humans, that why you spray it and do not touch it or eat it...the bugs climb, eat and live in the amount you spray on them..thats why they die.

there must be something in there worse than radiation..scary!

Answer 6

4 species that are not harmful to humans.. please provide here.. thanks