Wikipedia:Reference desk/Archives/Science/2012 June 29

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June 29[edit]

Rat poison[edit]

I have a pretty severe rat infestation in my house. The rats seem to mostly live in my roof and just come down to eat food. I've tried using warfarin based poisons to kill them. I placed them inside the roof through the manhole. The baits get eaten completely, but the rats don't die. The amount of poison I have placed up there has been up to 1kg of 0.105% warfarin. Essentially all of it was gone within a week but the rats were not. It's possible that the rats are warfarin resistant, but there's no other options at the local shops here. I'm thinking of taking a cereal and potassium cyanide and mixing together with honey to bind it and placing that in the roof. I don't have any pets or children. Would this be an effective mixture for erradicating my rats? 112.215.36.172 (talk) 04:42, 29 June 2012 (UTC)[reply]

Try calcium phosphide, it isn't so much a poison really, but it works, unless the calcium phosphide is past it's best before date. On contact with acid, like stomach acid, it produces diphosphane, which is spontaneously combustable. Essentially, it turns a rat crispy on the inside. Plasmic Physics (talk) 05:27, 29 June 2012 (UTC)[reply]
Can I mix that with cereal and honey as I was going to do with the cyanide? 112.215.36.177 (talk) 06:11, 29 June 2012 (UTC)[reply]
Dealing with mice, I've found glue traps to be effective, although not at all humane (they rip their faces off trying to escape). If they make rat-sized glue boards, I'd try those. StuRat (talk) 05:32, 29 June 2012 (UTC)[reply]
Okay, why would you *want* to do something like that in the first place? Use another method. That sounds sadistic and wrong. (talk) 01:40, 2 July 2012 (UTC)[reply]
Rat glue is available here, but I don't really know how to dispose of a live rat glued to a plate. I checked the instructions and their silence on the matter is telling. 112.215.36.177 (talk) 06:11, 29 June 2012 (UTC)[reply]
I'm guessing a high-tech euthanasia device is the preferred solution to that (*ahem*) sticky situation. Evanh2008 (talk|contribs) 06:16, 29 June 2012 (UTC)[reply]
For mice, I used one of those grabber thingies to get hold of the edge of the glue board, then put it in the sink and drowned it (had to hold it under with the grabby thing). If the rat is too big for that, drag it into a trash bag, take it outside, and crush it with a cinder block. Then toss it in the trash, or bury it if dead animals aren't allowed in the trash. Or, you could just let it die and rot in the attic, the smell will likely mostly go up and out. StuRat (talk) 06:22, 29 June 2012 (UTC)[reply]
What if the bait in the rat glue is also poison? Then it will die and I can just throw it away. Would that work? I'm also having trouble imagining how I would get a plate with a rat down from in the roof. I don't have an attic, just a crawl space so no lighting and very little room to move. The man hole is only about 1.5sqr feet, no fixed stairs or ladder and the drop is about 3m to the floor.112.215.36.177 (talk)
You could also shoot it on the glue board, perhaps a BB gun would work. Once you have it in the garbage bag (you might want to double bag it), just tie it shut and drop it down. Note that with poison they often die in really bad places, like in the walls, where they smell up the entire house. Or, worse yet, they can stagger into your living area, bleeding profusely. StuRat (talk) 06:41, 29 June 2012 (UTC)[reply]
This word count on the posts so far shows infestation by rodents:
  • rat : 16
  • man: 3
DriveByWire (talk) 15:03, 29 June 2012 (UTC)[reply]

Do you have any access to sodium azide-based pesticides? In sufficient quantity, the water-dissolved form should kill essentially anything. But given that, there may be restrictions on its use in your area, due to the potential for environmental contamination. If you are legally permitted to use it, simply spraying it on the glued rat should kill it, of course being very careful not to get it on yourself. Someguy1221 (talk) 06:29, 29 June 2012 (UTC)[reply]

I don't know of any sodium azide containing products that I have at my disposal. There's litterally piles of cyandide at the gold mine where I work, so I thought that would be the obvious choice. I also don't know where I would get the calcium phosphide mentioned above, but it sounds like it would allow me to not bother getting the corpses out of the roof, which is an advantage. I suppose the most important question is whether mixing any of these things with honey is going to liberate a toxic gas and kill me, or will it remain solid until the rat digests it. 112.215.36.177 (talk) 06:47, 29 June 2012 (UTC)[reply]

This is why we have professionals.--Shantavira|feed me 11:47, 29 June 2012 (UTC)[reply]

The dangers of amateur poison warfarin' make one sigh an' hide. DriveByWire (talk) 15:15, 29 June 2012 (UTC)[reply]

Let me point out that the OP geolocates to Jakarta, Indonesia. I doubt that many people here are qualified to give advice on getting rid of rats in a place like that, especially not knowing the setting of the house in question. And in any case I certainly wouldn't give advice to anybody who starts talking about using cyanide. Looie496 (talk) 15:54, 29 June 2012 (UTC)[reply]

I would be interested to know which mining company would allow people to walk off site with cyanide in what looks like South Sulawesi. We live in a rat-rich tropical environment and our house sometimes has guests in the roof spaces. We don't do anything to control them other than figure out how they get up there and cut any tree branches etc they use, allow cats into the house and allow any rat snakes we see to stick around. It's pretty effective. Sean.hoyland - talk 17:15, 29 June 2012 (UTC)[reply]
I'm on holiday in Bali right now, but I live in Australia. Unfortunately, if rats are next door, which I'm pretty certain they are, then they will just walk accross the ground to my house. Mining companies that use cyanide for gold leaching do not keep it very secure as a general statement about the industry. Obviously I'm not going to say who I work for, but it's literally sprayed around the place in heap leaches. I don't know why me saying that I thought cyanide might work would stop people from giving me advice. Wikipedia lists it as a rodenticide, and if it really is a terrible idea, shouldn't you want to advise against it? 112.215.36.174 (talk) 03:41, 30 June 2012 (UTC)[reply]

Cheese with Polonium 210 Count Iblis (talk) 18:15, 29 June 2012 (UTC)[reply]

Yeah, right. Moon rocks are expensive. 112.215.36.172 (talk) 03:25, 1 July 2012 (UTC)[reply]
My experience has been that cheese is some sort of miracle rodent bait only in cartoons. Peanut butter is much more effective in real life. Evanh2008 (talk|contribs) 01:35, 30 June 2012 (UTC)[reply]
A rat trap with peanut butter, yes; or with a bit of bacon or some other meat firmly tied on to the trigger. ←Baseball Bugs What's up, Doc? carrots→ 04:49, 30 June 2012 (UTC)[reply]

Using cyanide doesn't seem like such a good idea. The rats will taste just a little bit of the food and notice they become sick. And if one of them dies shortly after having eaten from a new food source, the others might be smart enough to avoid eating from that same food source. That's the reason for using slowly-acting poisons like warfarin. Icek (talk) 09:06, 30 June 2012 (UTC)[reply]

I don't like all this poison stuff. If you end up killing yourself with it, it looks bad for humanity versus ratkind in the global intelligence ranking. Not to mention that you'll have dead rats in your walls, getting ... juicy. Why not use a good old fashioned rat trap? Or a glue trap - apparently they still work for rats, and it has the added benefit of often providing you the live rat for ... wherever your imagination takes you. Or countless other mechanical options. Wnt (talk) 18:14, 30 June 2012 (UTC)[reply]

That may be valid, but did you consider the ramifications for humanity's global intelligence ranking if I were to kill myself with rat glue? Generally, I'm much better with chemicals than I am with anything mechanical. 112.215.36.172 (talk) 01:52, 1 July 2012 (UTC)[reply]
Glue boards have another advantage, in that most rodents start squeaking when they get trapped, providing their own alarm. That allows you to dispose of them before they die and start to rot. StuRat (talk) 20:09, 30 June 2012 (UTC)[reply]

Resolution[edit]

Combining several of the above solutions with some externally sourced ingenuity, I've decided how I will proceed.

Calcium phosphide and sodium azide were determined to be too difficult to procure. Rat glue was rejected due to my squeamish side not wanting to handle live rats who are angry enough to have literally ripped their own faces off. This suggestion from a previous reference desk question was rejected on the basis of unreasonable cost. Allowing cats and snakes into my roof was considered, but not accepted since the goal is to reduce the number of pests in my house. As a request made under the Freedom of Information Act revealed, attempts to acquire polonium laced cheese resulted in my name appearing on a suspected terrorist watch list. The original idea of cyanide was determined to be so 1940's.

The ideal toxin and route of administration was determined to be remotely actuated direct subcutaneous plumbum injection. In the end, much greater weight was given to the level of satisfaction achieved over actual probability that it will result in my house not having lots of rats in it. The chosen method is as follows:

  • Clear the house of human occupants by fabricating a story about a sale at Guess.
  • Place a suitable backstop against the door from my kitchen to the dining room.
  • Make a mound of peanut butter laced with bacon bits on a paper plate.
  • Set up a hide ~5 meters away with my gamo at the ready.
  • Wait.
  • Aim for the fat one.
  • ?????????
  • Profit.

Thanks for your help everyone.

Your proposed solution is self-contradictory because injured rats will die and rot in the walls (and feed other rats and pests!) like poison would. I recommend rat traps plus nitrogen asphyxiation. 75.166.192.187 (talk) 19:50, 2 July 2012 (UTC)[reply]

Borrow a cat. --Dweller (talk) 14:54, 4 July 2012 (UTC)[reply]

Slaughtering rats is unlikely to solve your problem; they reproduce very rapidly and can quickly make up losses. If you do manage to kill every female (or every male), then their cousins from next door will move in. They will just keep coming, like in Space invaders. You need to deny them access to food (including waste food and anything remotely edible), by keeping everything in containers that can't be gnawed into and can't be smashed by knocking over. This will motivate the rats to spend their time in your neighbour's house instead of yours. You also need to deny them access to your house entirely; this is hard as they can get through very small holes. They are most likely gaining entry by ascending your downspouts, going under your eaves and then descending to the larder. Block any small holes with screwed-up chicken-wire (which can't be gnawed), packed in too tightly to be pushed out. Many cats are too useless to sort out a rat, but plenty of fresh cat-urine deters rats from loitering on the premises. --catslash (talk) 20:53, 4 July 2012 (UTC)[reply]
I've seen lion droppings for sale on the internet to deter all kinds of animals... might work on rodents. --93.96.36.99 (talk) 05:50, 5 July 2012 (UTC)[reply]

iodine reacting with titanium[edit]

A few months back I posted this

"I have a titanium mug/cup. After drinking some milk I forgot to rinse it out and it sat and became gross. I decided to add some tincture of iodine along with some water to help sanitize the cup. After adding this in letting it sit for about a minute it changed color and started a foul smell that made my nose sting. Is it possible it reacted with titanium to release some sort of harmful gas or substance? — Preceding unsigned comment added by 64.38.198.61 (talk) 00:08, 4 March 2012 (UTC)

The elemental iodine (I2) is probably reacting with the titanium in the same way it reacts with aluminium. The product of that reaction would be titanium iodide, which is a very soluble salt, but it would also generate heat which volatilises some of the remaining elemental iodine. That stuff's not very nice to breath in. 203.27.72.5 (talk) 00:55, 4 March 2012 (UTC)

According to the titanium alloy article, titanium is usually alloyed with aluminium anyway. The reaction between iodine and aluminium is very spontaneous and can result in iodine vapor. 203.27.72.5 (talk) 04:28, 4 March 2012 (UTC)

The thing is I didn't see any actual cloud of vapor rise from the cup I just smelled it is that normal for this type of reaction? — Preceding unsigned comment added by 64.38.197.212 (talk) 12:04, 4 March 2012 (UTC)

If there had been enough vapor for you to see it in the air it would have been at a lethal concentration. Tincture of iodine only contains a few percent of iodine and not all of it is elemental either. I can imagine it would have been enough to smell but not enough to see by several orders of magnitude. 203.27.72.5 (talk) 20:14, 4 March 2012 (UTC)"


I haven't used this cup since then but I liked it a lot and it was expensive so im wondering is it safe to drink out of it?--64.38.226.89 (talk) 05:04, 29 June 2012 (UTC)[reply]

Without giving medical advice, I can point out that the product of the reaction, titanium tetraiodide would be in low concentrations and is highly reactive with water, so a few good rinses should remove it all. Titanium metal in and of itself is nontoxic. Handschuh-talk to me 09:37, 29 June 2012 (UTC)[reply]

Glucosamine and tendonitis[edit]

Where can I find scientific studies on the effect of the supplement glucocamine on tendonitis?

Just to clarify I am not asking for medical advice. — Preceding unsigned comment added by 99.146.124.35 (talk) 20:43, 29 June 2012 (UTC)[reply]

Our glucosamine article contains a long and well-referenced section on health effects; that would be a good place to start. Looie496 (talk) 20:52, 29 June 2012 (UTC)[reply]