בבא קמא קטו, ב
והתניא מים שנתגלו הרי זה לא ישפכם ברשות הרבים ולא יגבל בהן את הטיט ולא ירבץ בהן את הבית ולא ישקה מהם את בהמתו ולא בהמת חבירו
It was taught in a Baraisa: water that was left uncovered should not be spilled out in a public area, nor should one knead clay with it, nor should one lay in the dust with it, nor should one give it to his animal, nor the animal of his friend, to drink. (Bava Kamma 115b)
Don't Drink That Water!
The rabbis of the Talmud were very worried indeed about the health effects of water that had been left uncovered. This concern was codified by Maimonides, and later by Ya'akov ben Asher (d. 1340) in his famous halakhic work called the Arba'ah Turim.
טור יורה דעה הלכות מאכלי עובדי כוכבים סימן קטז
דברים האסורים משום סכנה
יש דברים שאסרום חכמים משום סכנה כגון משקין שנתגלו שיש לחוש שמא שתה מהן נחש והטיל בהן ארס אפי' אם שתו מהן אחרים ולא הוזקו אין לשתות מהן שיש נחש שהארס צף למעלה ויש שארס שלו מפעפע עד אמצעית המשקה ויש שהארס שלו שוקע לשולי הכלי לפיכך אפי' שתו ממנו אחרים ולא הוזקו אין לשתות מהן דשמא ארס של הנחש ששתה מהן שוקע ואלו המשקין שיש בהן משום גילוי מים יין חלב ודבש ושום כתוש
Tur, Yoreh De'ah 116. Things that are Prohibited Because they are Dangerous
There are things that the rabbis of the Talmud prohibited because they are dangerous. For example, liquids that were left uncovered, because of the possibility that a snake drank from the water and expelled some of its poison into them. Even if others had drunk from the liquid, and not been injured, one should not drink from them. For some snake venom floats on the surface, and some sinks to the middle and some moves to the edges of the vessel. Therefore, even if others had drunk and had suffered no harm, one should not drink from them, for perhaps the venom from the snake that had drunk the water had sunk to the bottom. The following liquids should not be drunk if they were left overnight in an uncovered vessel: water, wine, milk, honey, and crushed garlic...
The normative Code of Jewish Law, the שולחן ערוך agreed, but added an important caveat:
שולחן ערוך יורה דעה הלכות מאכלי עובדי כוכבים סימן קטז סעיף א
משקים שנתגלו, אסרום חכמים דחיישינן שמא שתה נחש מהם והטיל בהם ארס. ועכשיו שאין נחשים מצויים בינינו, מותר
The rabbis forbade drinking from liquids that were left uncovered,. They were concerned that a snake may have drunk from them and expelled some of its poison into them. But now that snakes are not commonly encountered, this is permitted. (Shulchan Aruch Yoreh De'ah 116:1)
So today it is permitted for us to drink from an uncovered pot, but only in a place that does not have a problem with poisonous snakes. Which is not helpful. There are poisonous snakes in nearly every state in the US, resulting in about 2,000 human envenomations each year, and we have noted before that Israel has its own problem with snakes, including the Palestinian Viper. The World Health Organization estimates that snakes kill between 20,000 and 94,000 people per year. So exactly where this leniency of the Shulchan Aruch might apply is not clear.
But is drinking snake venom indeed dangerous? Maybe not. In 2012 India Today reported that police in New Delhi had seized about half a liter of snake venom to be used "in high-end raves planned for Valentine's Day in and around the national capital." Apparently the venom, when ingested, produces a euphoric state. Who knew?
Video evidence - Drinking Cobra Venom
It is really hard to find any peer-reviewed scientific studies about people drinking snake venom, because, um, it's a silly thing to do. But that doesn't mean it hasn't been done. So where could we turn to find people doing silly things? YouTube of course. (Warning. This video involves spitting. Not by the snakes.)
Want more? Ok then. Here's another one. This time it involves drinking the venom directly from spitting snake. Apparently, these kind of human interest stories are popular in India.
Why it is safe to drink snake venom
If you are a diabetic and take insulin, or know someone who does, you may have wondered why the drug has to be injected. It would, after all, be much less bothersome to swallow an insulin pill than to inject insulin several times a day. The reason is that insulin is a protein, and like all proteins, it is easily broken down by heat and, more importantly, by the acid environment in the stomach. Our gastrointestinal tracts evolved to break down proteins into their building blocks - and they perform a wonderful job doing precisely that.
Like insulin, snake venom is a complex protein. And so, like insulin, it too is easily broken down in the very acidic environment of your stomach. Of course, if intact venom gets into your bloodstream, it could kill you. But if you drink venom, then the intact protein never does get into your bloodstream. You don't need to be an Indian snake charmer to safely drink snake venom. You just need a working digestive system.
HOW SNAKES DRINK
The Talmud was concerned that snakes leave venom in water from which they drank, and that a person drinking from that water would then suffer from envenomation. As we have seen, this concern has no biological basis, although theoretically, if there was an open cut or ulcer in the mouth, ingested venom could get into the bloodstream and then cause its havoc. But there is another reason why the talmudic concern is overstated. Snakes, you see, don't leave any venom when they drink water. As you may have noted from watching the first video, it takes a lot to get a snake to expel its venom - like sticking a blue pen in its mouth. Venom is a snake's most precious commodity, and it has evolved to protect that commodity. Snakes only release venom when they are in danger, or ready to strike their prey, and not otherwise. Want a great example? The venomous rattlesnake. That species has evolved a warning rattle to tell would-be predators that if they get any closer, they will be bitten. This only makes evolutionary sense if it was in the snake's best interest to do everything possible to conserve its venom.
In a fascinating article on how snakes drink published in The Journal of Experimental Biology, David Cundall notes that a snake's tongue does not carry or move water, and that "in many snakes, the tongue does not visibly move during drinking." That leads to the conclusion that snakes are suction drinkers. And that makes them even less likely to leave any venom behind in the water.
So let's put this all together:
- Snakes don't release their venom unless they are threatened or hunting.
- Snakes use suction when they drink water. Their mouths are not open, which is needed when they are expelling venom.
- Snake venom is not dangerous when drunk.
- (If somehow venom did get into the water, it would be greatly diluted.)
So there is no danger if you were to drink from water from which a venomous snake had drunk. None.
Rashi's Two Explanations of Today's Passage
In today's page of Talmud, we are warned not to drink water left standing, because of the danger of a venomous snake having drunk from it. That danger, as we have seen, does not exist. But the Talmud also warns us not to use this water to sprinkle on a dirt floor to keep the dust down. According to Rashi, the concern is that a person might cut her foot on a sharp stone left on the floor, which would then allow the venom that was in the water that was sprinkled on that floor to enter the bloodstream. Now that is an incredibly unlikely event, but it is certainly possible, and Rashi's point is absolutely correct. The danger is only if there is an open wound that would allow the venom to enter the blood stream. (שלא יעבור עליהם אדם יחף ויכנס ארס של נחש ברגלו ע"י מכת צרור וימות.) It is fascinating to compare Rashi's explanation here with his explanation of the the identical passage found in Avodah Zarah (30b).
לא ישפכם: שמא יעבור אדם יחף ויעמוד הארס בין קשרי אצבעותיו וכיון שנכנס מעט ונוקב בבשר שוב אין לו רפואה. רשי, עבודה זרה ל, ב
There, Rashi notes that if "venomous" water was sprinkled on the floor, a person might step on it and absorb the venom through the skin of his toe joints. Once that happens, "שוב אין לו רפואה" - there is no medical treatment. What Rashi may not have known is that snake venom is not dangerous if it gets on your skin, because it is not absorbed from there into the bloodstream. So his explanation in Avodah Zara is not correct, unlike his explanation of the passage in today's daf.
Bye Bye Bava Kamma
And that brings us to the end of Talmudology on Bava Kamma, which we will finish learning next Tuesday. We've discussed all kinds of topics:
And more besides. Now it is time to turn to the next tractate. I'll see you on the opening page of Bava Metziah, when we will discuss game theory and the work of the Israeli Nobel prize winner Robert Aumann.