Tarantula toxicology

[TBONE]

I was wondering (based on a story I heard) about this.

Basically I know (unless you are severly allergic) a tarantula bite cannot kill a human. However if say a human being fell in to a container that contained let's say 100 T's and they all bit him or even just half did; what would be the outcome.

My opinion is it is venom volume so if he is bitten by 50/100 T's then that would be it game over.

The reason I ask is because I heard a story a few years ago (and it could be an urban myth) that a gangster in Manchester (UK) exacted revenge on someone by putting that person in a large cage with over 100 T's and that they were mexican red knees; somehow they were deliberately agitated and bit the person thrown in and he died a violent death. How true it is I don't know; I can say there are some very nasty and wierd peopel in UK and especially the northern parts. Just wanted your opinions.

Sean

 

[forrestpengra]

No laugh... just a chuckle. Anything can kill someone in quantity.

Please understand that Tarantulas are not malicious in nature and do not attacked unprovoked.

If you were talking dogs or cats, all it takes is one bite. There was an article in the Journal of Toxicology in which every dog tested died when bitten. I believe most of the T's were of the old world Selenocosmia genus.

 

[DrJ]

That story has to be myth. It makes no sense.

For starters, just because there are many spiders, snakes, etc in one small space, doesn't mean they will bite anybody. Animals are NOT out to get you.

However, in regards to toxicology, no spider (tarantulas included) or scorpion has EVER killed a fully developed adult, healthy human being. Perhaps that is a good start to your question.

 

[Bill S]

Sounds more like the plot of a grade B horror movie. If you put that many Brachypelmas (Mexican Red Knees) in a cage with a person, the first impact is that you will have is a lot of squashed tarantulas. The spiders will try to hide or flee, not attack. You'd probably get a lot of urticating hairs kicked up and I wouldn't want to have to breathe in that cage - but the person in the cage is not going to get bit.

If, however, someone were to extract venom from a large number of tarantulas and inject it in a person - you could get a pretty severe reaction. With some species, this could be fatal.

 

[LirvA]

If you were talking dogs or cats, all it takes is one bite. There was an article in the Journal of Toxicology in which every dog tested died when bitten. I believe most of the T's were of the old world Selenocosmia genus.

Damn I didn't know that. A T bite is lethal to cats and dogs? I'm new to the hobby and don't really know much about the different species so I don't know if that genus (?) has potent venom or not.

 

[brian abrams]

Nastiest T bites

Damn I didn't know that. A T bite is lethal to cats and dogs? I'm new to the hobby and don't really know much about the different species so I don't know if that genus (?) has potent venom or not.

Old World Tarantulas have potent venom. These are Tarantulas from Asia, Africa, Malaysia, South Pacific, Australia, etc. New World species bites are usually compared to a bee or wasp sting. These are from North, Central & South America. NW species DO carry irritating bristles on the back of their rumps called urticating hairs, that they will kick off in defense, to compensate for the lower potency venom.

 

[Harlock]

Yeah, if I was stuck in a room with 100 Ts, I wouldn't be worried about getting bit much. I'd be more interested to watch their numbers drop from cannibalism.

 

[jeryst]

I cant see a gangster spending a lot of money on a bunch of T's, then putting them in a room, then finding a way to agitate them, just to try and kill someone, only to maybe have it work.

Most gangsters are practical. A baseball bat is cheaper - lol.

 

[Mattyb]

That story has to be myth. It makes no sense.

For starters, just because there are many spiders, snakes, etc in one small space, doesn't mean they will bite anybody. Animals are NOT out to get you.

However, in regards to toxicology, no spider (tarantulas included) or scorpion has EVER killed a fully developed adult, healthy human being. Perhaps that is a good start to your question.

Huh? so your saying no one has ever died from a black widow or sydney funnel web bite? A sydney funnel web can kill an adult within 15min.

 

[Bill S]

Huh? so your saying no one has ever died from a black widow or sydney funnel web bite? A sydney funnel web can kill an adult within 15min.

Despite the popular myths about this, they are not that deadly. The bite can be serious, but the 15 minute death from spider bites goes right along with the "15 pacer" stories about tropical venomous snakes that deliver a bite that kills you by the time you run 15 paces.

 

[Mattyb]

Despite the popular myths about this, they are not that deadly. The bite can be serious, but the 15 minute death from spider bites goes right along with the "15 pacer" stories about tropical venomous snakes that deliver a bite that kills you by the time you run 15 paces.

Ok, but still people have indeed died from spider bites.

 

[Jackuul]

Actually the Atrax robustus has not killed people in years due to the development of antivenin. While they may not be as deadly to many animals, primates (us) are very susceptible to their venom, which contains robustotoxin which causes a rapid opening of sodium ion channels in the primate autonomous nervous system.

Source

The solution structure of robustoxin, the lethal neurotoxin from the Sydney funnel-web spider Atrax robustus, has been determined from 2D 1H NMR data. Robustoxin is a polypeptide of 42 residues cross-linked by four disulphide bonds, the connectivities of which were determined from NMR data and trial structure calculations to be 1–15, 8–20, 14–31 and 16–42 (a 1–4/2–6/3–7/5–8 pattern). The structure consists of a small three-stranded, anti-parallel β-sheet and a series of interlocking γ-turns at the C-terminus. It also contains a cystine knot, thus placing it in the inhibitor cystine knot motif family of structures, which includes the ω-conotoxins and a number of plant and animal toxins and protease inhibitors. Robustoxin contains three distinct charged patches on its surface, and an extended loop that includes several aromatic and non-polar residues. Both of these structural features may play a role in its binding to the voltage-gated sodium channel.

It won't kill you in fifteen minutes.

Untreated, it will kill you within two hours - depending on where it bit you, the effects can take longer, or not so long, along with body mass. It causes neurons to fire and eventually leads to a total failure of your autonomous nervous system. Atrax robustus is notorious for full envenomations as well, and is actually the only spider considered "aggressive" as they will chase you short distances, and become agitated easily.

So the statement that "no spider (tarantulas included) or scorpion has EVER killed a fully developed adult, healthy human being" is absolutely false.

"Despite the popular myths about this, they are not that deadly." I invite you to test this thesis with a full envenomation of the Atrax robustus, a stop watch, and without medical intervention using antivenin.

The Atrax robustus, and related funnelwebs, make OBTs look like kittens. This is a species that you don't mess with, you don't harass, and you don't take chances with. Of all the species of spider on the planet, this single species is the one that will destroy you if left untreated, and within hours, if not less than an hour.

Then again, A. robustus is not a tarantula. It is true that no tarantula on record has every killed a human being, regardless of medical status of being healthy or unhealthy, or even pre-existing conditions. Tarantulas have a venom that, while potent in many old world species, is very different in many respects and does not produce the effects on human biology that are seen from Atrax and the other FWS.

 

[Bill S]

From "Spider Myths Site" http://www.washington.edu/burkemuseum/spidermyth/myths/downunder.html:

According to the Australian Museum spider page, the number of human deaths from authentic spider bites of any kind in Australia since 1979 has been zero. A recent published medical study followed 750 genuine Australian spider bite cases with identified spiders over 27 months (1999-2001). Only 44 bites (6%, mostly redback spider bites) had significant effects. Only 6 redback bites and 1 Atrax bite were serious enough to need antivenom. In no case was there any sign of allergic response to spider venom, and I have only seen one such case in North America in 35 years.

Atrax robustus, the Sydney Funnelweb Spider, is often publicized as the "world's deadliest." Authentic medical information (click here for details) suggests otherwise. There have been no deaths (out of 30-40 bites per year) since antivenom was introduced in 1980. During the 53 year period 1927-1979 there were 13 or 14 known deaths, which would be a death rate of under 1%! Although one child died in 15 minutes, adult fatalities typically took 2-3 days. 90% of Atrax bites are judged not serious enough to need antivenom.

 

[Arachnethegreek]

The Sydney funnel web (Atrax Robustus) has earned it's fearsome reputation through the following; 1) over popularized media programs such as "worlds deadliest" and dramatization of news reports. 2) the potentcy in children, as many of the bite reported as causing death or hospitalization areto do with children under the age of 10. 3) the class of venom. Atrax venom (as previously noted on this thread) is developed as a vertebrate defense mechanism, possibly against wild dogs, dingos etc. This also has the detriment of cause primates a problem with our own body structure being similar (to the degree of mammalian, and similar size) comparing a human response to a canine response the effect is much different, a cannine will last meteomenta before visible signs are present and mere hours if lucky before death. Anti venin is available because of sheer potentcy, a rarity among arachnids. Their attitude also present an issue for reputation as when males mature an seek a mate just after the rainy season the males become hyper aggressive, attacking and envenomating anything in reach.
Personally, I wouldn't go near these guys with a nine and a half foot pole.

 

[ArachnoYak]

Despite the popular myths about this, they are not that deadly.

So the 12-14(numbers vary depending on your source) deaths attributed to Atrax robustus before the introduction of antivenin would imply that this spider is "not that deadly"? The term "myth" would imply an untruth. The truth is these are deadly spiders.

Quoting a website that offers general information from an American museum is hardly convincing.

I've consulted many sources rather than just one(books included), and I would encourage others to do the same.

More importantly the potency of venom differs between the male and the female of the species, with the added component of robustoxin only present in the venom of the male. The presence of robustoxin increases the lethality of the venom.

The fact that the venom is primate specific renders any toxicity tests done on other mammals pointless.

 

[DrJ]

I will be honest and say that I am not all that familiar with the funnel-webs. However, a death to a fully-developed healthy adult I'd have to see evidence of. I can tell you without hesitancy that such an incidence has never occurred due to a widow bite. My evidence/proof is the lack of it. If there's never been a report, it must not have happened. If this has happened with the funnels, let's see it.

 

[BigJ999]

Funnel Web's are dangrous very dangrous but i hear they have anti -venom around now. Still its not the most venomus spider i the brazilan wondering spider is

 

[Arachnethegreek]

Also @OP the possibility of an allergic reaction had been discussed on these boards before, and from the chemisty/medical analysis present by another poster it seems legit. It stated that tarantula venom lack a certain protein present in bee venom. It's that protein that causes anyphylactic (sp?) reactions. I'm not a chemistry buff so I can't explain in true detail, as it wassnt my post nor my knowledge.

 

[Mattyb]

I will be honest and say that I am not all that familiar with the funnel-webs. However, a death to a fully-developed healthy adult I'd have to see evidence of. I can tell you without hesitancy that such an incidence has never occurred due to a widow bite. My evidence/proof is the lack of it. If there's never been a report, it must not have happened. If this has happened with the funnels, let's see it.

http://en.wikipedia.org/wiki/Australian_funnel-web_spider


27 deaths within the past 100 years. I understand now a days its very rare to die from a spider bite, but my point is, it has happened.

 

[DrJ]

http://en.wikipedia.org/wiki/Australian_funnel-web_spider


27 deaths within the past 100 years. I understand now a days its very rare to die from a spider bite, but my point is, it has happened.

But! Even your source states that "most victims were young, ill or infirm." So, validation that a funnel-web has the capacity to kill a healthy adult has yet to be seen.