Wikipedia:Reference desk/Archives/Science/2015 June 10

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June 10

Evidence that organic food can be unhealthy/health hazard?

In the article for Sewage see reuse in agriculture. Is this evidence that organic food poses a serious health hazard? Please address the context of this subject. No need to try and badlash preservatives/processed food stuffs. Agent of the nine (talk) 14:45, 10 June 2015 (UTC)

The main risk from organic food comes from the use of manure instead of chemical fertilizers. (While chemical fertilizers are often derived from manure, the processing ensures that they are sterilized.) Thus bacterial contamination from the manure is a possibility. There's also a risk to nearby water supplies. StuRat (talk) 14:51, 10 June 2015 (UTC)

So with your comment in mind (StuRat) do you think that wastewater along with "non processed" manure increases the health risk even more? And perhaps in times of drought (like the one in california right now) since the demand for water is always high and the supply is now low maybe farmers might resort to using wastewater at higher frequencies? what do you think?Agent of the nine (talk) 15:53, 10 June 2015 (UTC)

What Stu (or me, or any of us) thinks is irrelevant; we shouldn't be offering un-sourced opinions here. I for one am very skeptical of the claims Stu has made above. If you want a reliable scientific source on food safety of organic foods (including the use of manure), see this recent review article, A Comparison of the Nutritional Value, Sensory Qualities, and Food Safety of Organically and Conventionally Produced Foods [1]. In contrast to what Stu says above, the authors conclude that "There is no evidence that organic foods may be more susceptible to microbiological contamination than conventional foods. "

As for wastewater, here's an entire book: Wastewater irrigation and health [2] - wastewater can indeed be used safely in agriculture, but there are additional risk factors that need to be mitigated, relative to fresh water irrigation. On WP, see Agricultural_wastewater_treatment, Reclaimed_water, and greywater. SemanticMantis (talk) 16:17, 10 June 2015 (UTC)

@semanticmantis. As always thank you for your references. But I dislike EVERYTIME you mention "what anyone thinks is irrelevant". Irrelevant to you maybe but there's nothing wrong with honest conversation in the desire to learn. I care what people think because gaining different perspectives is a part of learning. In no way did I represent my speculation as scientific evidence. Again I look forward reading your references. So you admit because additional steps must be taken to ensure safety of wastewater treatement there is a greater potential health hazard? As long as those steps are taken no problem. But the more steps in a process the greater chance something can go wrong. Your first reference also requires that I download a file to view the contents.. References should not require addtional action to view them let alone downloading something Agent of the nine (talk) 17:05, 10 June 2015 (UTC)

Semanticmantis is quite correct. As it says in the Wikipedia:Reference desk/Guidelines "The reference desk is not a chatroom, nor is it a soapbox for promoting individual opinions. Editors should strive to accurately and fairly represent significant views published by reliable sources" Unfortunately, providing references from reliable sources is something StuRat consistently fails to do. Richerman (talk) 17:31, 10 June 2015 (UTC)

(warning, on preview, my language may seem opinionated and snarky - I don't mean to be rude but I also don't want to re-type the whole comment.) Ok, I think that composted manure is perfectly safe. I think manure is much less damaging to agroecosystems than N fertilizers made from fossil fuels and the Haber process, which, together with the chisel plow, have had catastrophic effects on the soil carbon reserves throughout the corn belt of the USA, and also contributed to atmospheric carbon dioxide increases and climate change. I think that my references back up my assertions. I think it is irresponsible to post opinions here that are not backed up by reliable sources. I think that wastewater probably needs more safety measures than freshwater irrigation, but I'm not sure how that comes in to total risk assessment, and I have not yet read the book I linked to. I think that there are many highly educated experts that respond here, and I also think that there are many people who suffer from the Dunning–Kruger_effect. Since we are not in the business of appealing to authority, I think we should be skeptical of claims that are not presented with supporting evidence :)

Now, on the subject of that reference - that is an article in an academic journal, it has been peer reviewed, and is a Review_article. It's about the most trustworthy and expert type of scientific findings we have, and it also appears in a prestigious journal dedicated to comprehensive reviews in the field. The other link is a freely downloadable PDF published by a non-profit scientific research association. Both of these are far more reliable than any WP article or science blog, but you will have to download them. In fact the first article is behind a paywall, but feel free to email me (use talk page link) or ask at WP:REX if you'd like a copy to read yourself. There is absolutely no requirement here or in any scientific discussion that a reference must be freely available on the internet with just one click from anywhere in the world (I agree that it is preferable, but I was not able to find any good, reliable scientific reviews of the topic that are available via open access publication). Just be glad you don't have to actually physically go to an academic library (and be a member), or pay ~$35 per article to read it! I think Academic publishing is a total mess these days, and it is making a few people rich while preventing dissemination of results to the public and to other scientists, but that's a topic for another day... Finally, I might also think that an invisible pink unicorn is out to get me, so please be wary of un-sourced claims by pseudonymous internet people! SemanticMantis (talk) 17:43, 10 June 2015 (UTC)

Well done! quite a retort indeed. I was just hesitant on downloading is all. I'm glad you shared what you THINK =) Since there is so many people in the world would it be reasonable to produce food only organically? Or because there are so many people to feed synthesizing ammonia and other methods you mentioned are the only reasonable way to produce enough food? (so far) AND if you do believe that an invisible pink unicorn is out to get you we can all learn something special about you Agent of the nine (talk) 18:09, 10 June 2015 (UTC)

And without downloading anything it tells you in the abstract "There is no evidence that organic foods may be more susceptible to microbiological contamination than conventional foods". Richerman (talk) 18:14, 10 June 2015 (UTC)

To answer your new question you should read Will Organic Food Fail to Feed the World? the summary of which says "A new meta-analysis suggests farmers should take a hybrid approach to producing enough food for humans while preserving the environment" Richerman (talk) 18:25, 10 June 2015 (UTC)

Additional WP articles at Food_security and sustainable agriculture. These are essentially open questions, and experts in the field still disagree on some issues. Many scientists believe that current agricultural practices cannot be sustained in the long run. Many believe that agronomy research will continue to increase food supply. Many believe that political and social solutions are most apt, as about 1/3 of global food is currently wasted [3]. Here are a few recent science articles that discuss the root of the issue, namely net primary productivity, and how much the world can make [4] [5]. See also the first few refs in each article. First article is paywalled, same deal as before, ask at WP:REX or email me if anyone wants a copy. Also @Agent of the nine:, please have a look at and follow WP:INDENT - this thread has gotten pretty confusing to follow, and it will be easier if you use our indentation style conventions. SemanticMantis (talk) 18:46, 10 June 2015 (UTC)

• What counts as inorganic food? Pop Rocks, Tums, and seltzer water? μηδείς (talk) 18:29, 10 June 2015 (UTC)

Yes, this is a regrettable problem in nomenclature. "Conventional" produce now means "produced with intensive reliance on synthetic pesticides and fertilizers", while "organic" is described at the link below. SemanticMantis (talk) 18:46, 10 June 2015 (UTC)

If you read the intro paragraphs from this page that should answer your question.Agent of the nine (talk) 18:34, 10 June 2015 (UTC)

• Note that if the question is how to best feed the world, avoidance of meat production is key, as it wastes lots of resources. An exception is places unfit for farming, where grazing animals can still survive. StuRat (talk) 18:40, 10 June 2015 (UTC)

I think you mean "unsuitable for arable farming", Stu. Dbfirs 06:58, 11 June 2015 (UTC)

"Arable farming" seems to be British English. I've never heard the phrase used in the US. To me, that's just "farming". We might use the word "farming" to apply to raising animals, but then would make that fact clear, by saying "I own a dairy farm", for example, rather than just "I own a farm". StuRat (talk) 14:51, 12 June 2015 (UTC)

• Here's an article on the risks of manure fertilizer to those living nearby: [6]. And as to the argument that "risks can be handled if the proper steps are taken", of course that's true, but it's also predictable that those steps won't always be followed. Most food poisoning cases would be avoided if the food was prepared correctly, but that doesn't mean we shouldn't try to keep salmonella, listeria, E. coli, etc., out of the food chain, to begin with. And E. coli, in particular, comes from manure. Here's some of the additional safety steps to take when using manure: [7]. StuRat (talk) 21:29, 10 June 2015 (UTC)

That's an article about the risks of living near a (not organic) pig farm, or living near fields where pig manure is used. It is not about the risks of using manure as a fertilizer to grow organic foods. The manure isn't treated properly, and the pigs are fed high doses of antibiotics, leading to antibiotic-resistant bacteria. As a side note, many organic farms do not use manure of any sort, and I've never heard of any using pig manure - it's nasty stuff, here's a guideline saying pig manure should not be used for organic crop production [8]. And none of these finding change the quote I put in bold above - there are plenty of ways to get E. coli and other bugs in conventional crops. Anyway, that is a good ref and an important concern for the safety of conventional pig farming and using pig manure on conventional crops, so thanks for posting. If you had posted that ref in your first post, I wouldn't have given you a hard time. That wasn't so hard, was it? :) SemanticMantis (talk) 14:53, 11 June 2015 (UTC)

In my experience, the word "organic" means "more expensive". Plus you can get some deadly bacteria as a bonus. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:22, 10 June 2015 (UTC)

If Bugs read Poison on a Plate: Dangers in the Food We Eat and How to Avoid Them he will realize that the potential for dangerous Bugs (no pun intended) are in our supermarkets -regardless of origin. Despite home refrigerators and food and hygiene laws, food poisoning is on the increase because people believe the food they buy is totally safe before the eat by date and so don't abide by there grandmothers simple advice.--Aspro (talk) 23:36, 10 June 2015 (UTC)

So it's just a question of how much you want to pay for that risk. ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:49, 10 June 2015 (UTC)

I would say that it was wiser to invest some time in learning how to mitigate the risk in the first place. Clientèle eating in high-class Michelin star restaurants can and do still suffer food poisoning from time to time. So price doesn’t come into it. --Aspro (talk) 13:10, 11 June 2015 (UTC)

I would note that whether you are reading wikipedia online or a webpage online, you are by definition downloading something. A PDF is not HTML, but it's such a common part of the web that some browsers come with built in PDF viewers and many others have PDFs viewer plugins as standard. Realisiticly the nature of scientific publishing (or really a lot of non ebookj publishing on the web) means that if you are truly interested in science, you really need to learn to deal with PDFs. Nil Einne (talk) 21:32, 11 June 2015 (UTC)

• I am sorry if I missed it, but what is this "grandmother's simple advice" to which you refer, Aspro? My neighbor's grandmother was infamous for advising "just eat around the green parts" while my own father's mother said adding sugar will "take care of it." μηδείς (talk) 04:42, 12 June 2015 (UTC)

@μηδείς. A few memories are still etched into my failing and ossified mind: Don't store cooked food with raw nor prepare them together. Wipe down and scrap chopping boards after you use them and leave to dry (rapid desiccation kills bacteria before they can become dormant spores). Always wash hands between tasks. Wash hands frequently with coal tar soap AND a nail brush. Wash your hands always after going to the loo. Don't allow anyone in the kitchen with a whitlow. Lime wash the inside of ones larder each year (these where rooms we used before refrigerators and lime wash is a steradent ) . Pluck and eviscerate chickens and other animals out in the outhouse -not in the kitchen. If fish and chicken are prepared at the same time and the fish start to smell off – don't eat the chicken. (I only found out recently that the bacteria that give the off smell to fish is not pathogenic but the chicken stored at the same temperature will more than likely be teeming with dangerous bug. Yet, not smell off) Etc... If I broke any of these rules I would have got get a clip round the lughole. 'You' may know that they make sense yet I see people today (in this modern world of antibiotics ) demonstrably brake these rules every day, only to then blame the food suppler if they fall ill. Ready prepared and sliced salad vegetables, is another daft innovation, as far as food hygiene goes. I am not saying organic food don't have any health hazards at all. After all a sack of organic spuds dropping on one's head from a great height may give one a server headache.--Aspro (talk) 14:06, 12 June 2015 (UTC) --Aspro (talk) 14:06, 12 June 2015 (UTC)

Thanks, Aspro but I am actually a trained head cook, as well as well versed in biology. The stories above were not advice, but scary/funny anecdotes. I find dealing with other people's cooking habits difficult. For example, my father will make ham and bean soup, boil the pot all day, then take off the lid to let it cool on the stove for six hours before putting it in the fridge so that he doesn't heat the refrigerator up.

Not only does he leave it uncovered, he pours unused soup back in. I have told him repeatedly that allowing it to sit open until it achieves room temperature simply allows germs to colonize it. I have told him repeatedly food comes out of the cookware, it never goes back in, and that if he left the pot covered when it was still at a boil the insides would be sterile until he removed the lid. He could safely leave the covered pot on the stove over night to cool. (See perpetual stew, not the most helpful of sources, though.)

My mother, on the other hand, automatically throws out all food that's two days old, including pickled items and chinese mustard and hot peppers, which are in effect self-preservatives, and milk that's not gone bad. That is part of her nesting regimen which requires her to throw out heirlooms and to get new carpeting and furniture every 2-5 years.

@μηδείς Agree that is not a recommended bean and ham soup method for today but as he is still making it and not pushing up the daisies it might come back to biology again. The obvious thing that springs to mind to explain why he has gotten away with it so long is that he adds the unused soup whilst the main pot is hot enough to bring it up above 65°. Also, the sort of bacteria laden mots floating about in the kitchen are also more likely to only inoculate it with bacteria that produce heat liable toxins which will be destroyed on reheating. I don't know if cooked garlic and herbs have the same antimicrobial effect when raw but they may also have an effect. If the ham is not lean and a layer of fat floats on the surface that can also act as a bacterial barrier. Fat and aspic as you will know, was often used to preserve food for the short term. Potted shrimps ( in butter) keep for days. Oh gosh. All this is making me feel I'm hungry. The OP question was about organic food and my point is: That 'anything' that supports bacterial growth has to be treated with respect and a few simple rules mitigate almost all of them. Of the remainder, food hygiene practices prevent anthrax and other nasties form getting into the food chain.--Aspro (talk) 20:55, 12 June 2015 (UTC)

I get "server headaches" all the time. :-) One of the most common sense pieces of advice which now seems to be ignored is "examine your food before you cook it or eat it". People now seem to rely exclusively on the date on the package, and if the date is good they are sure it's fine, whether it smells or tastes bad, has gone cloudy, changed color, grown fuzz, or is teeming with maggots. StuRat (talk) 14:40, 12 June 2015 (UTC)

Yes, Stu. My mother is the opposite side of that coin. She throws everything out on the expiration date. I have tried to convince her that spoiling a physical change, not a magical hour at which your coach changes back into a pumpkin. μηδείς (talk) 15:11, 12 June 2015 (UTC)

Same here. I can't convince her that the date is almost meaningless, as the conditions under which the item is stored make it last 10 times as long or 1/10th as long. Although she does have the bad habit of taking the lids off of anything she might use for the meal, and leaving them off the the entire meal, ensuring they get a proper dose of airborne bacteria. If I am going to use spaghetti sauce, for example, I open it, immediately pour out what I need, then the lid goes right back on. StuRat (talk) 15:53, 12 June 2015 (UTC)

I think it's funny that certain posters (usually admins) say that WP is not a chat room or a soap box. however that rule seems almost entirely uninforced. oh the LOLZ just look at what my post turned into!! Agent of the nine (talk) 16:15, 12 June 2015 (UTC)

Arabian desert

If the outflow of the Jordan river, Euphrates and Tigris was diverted towards the Arabian desert, could a majority of the desert eventually turn green? 84.13.148.183 (talk) 18:27, 10 June 2015 (UTC)

The question would be whether the outflow would exceed the evaporation rate. In reality, it would certainly exceed the evaporation rate until the lake formed had a large enough of a surface area to equal the flow rate. So, you would get a terminal lake of some size which would become saltier and saltier until the salts started to precipitate out of solution, ending up with something very much like the Dead Sea. StuRat (talk) 18:38, 10 June 2015 (UTC)

In other words, it is impossible to turn the Arabian desert green. 84.13.148.183 (talk) 19:51, 10 June 2015 (UTC)

If all of humanity were willing to set this as our top priority, I'm sure we could get it done. So, in that sense it's possible. But practical, no. See Salton Sea for an example of how something similar happened accidentally. StuRat (talk) 21:14, 10 June 2015 (UTC)

It's not impossible. THIS could be used to turn the arabian desert green. Agent of the nine (talk) 20:06, 10 June 2015 (UTC)

It may be possible with a proper irrigation system - but it takes a lot of work see [9] Richerman (talk) 21:28, 10 June 2015 (UTC)

This is not a purely hypothetical question and it does not require speculative answers. The science of hydrology exactly quantifies how much water flows out of a river. In particular, the Tigris, Euphrates, and Jordan rivers have been extensively studied.

• Here is a summary study from Professor James Lee of American University: the Tigris-Euphrates River Dispute at the website for The Inventory of Conflict & Environment.
• From the same department, the Jordan River Dispute,including a political history summary, and a quantitative review of water use, population requirements, and river outflow.
• The water from the Jordan River has been diverted since the 1967 War. In fact, many historians consider the National Water Carrier of Israel, which diverted water into Israeli-occupied territory, to be a causative precursor to the war. There is barely enough water to keep the Jordan River valley and the Sea of Galilee at their present levels.
• Here is a study from the Yale School of Forestry and Environmental Studies on engineering impacts: Restructuring of Water Usage in the Tigris-Euphrates Basin: The Impact of Modern Water Management Policies. This provides a good scientific overview.

Diversion of the outflow from these rivers would not supply enough water to irrigate the entire Arabian desert. Not only is this an impracticality from a quantitative, civil engineering standpoint - it's also a complete no-go from the perspective of political science and international relations. The users of water from these rivers have actually gone to war repeatedly over small engineered changes in flow rates of the water. Multiple horrific wars have been fought over lesser rivers.

Nimur (talk) 23:11, 10 June 2015 (UTC)

Will the Great Attractor beat Dark Energy?

I.e. will we implode into the Laniakea Supercluster, or be torn from it by Dark energy? Hcobb (talk) 23:12, 10 June 2015 (UTC)

Yes. ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:49, 10 June 2015 (UTC)

The dark energy can be thought of as an acceleration of Λ·r where Λ ≈ 4·10⁻³⁶ s⁻² (I think—I may be off by a factor of 2 or 3). Taking 5·10¹⁶ M_Sun as the mass of the great attractor and 200 MpcMly as the distance, that gives an acceleration of 8·10⁻¹² m/s² (outward) from dark energy and 2·10⁻¹² m/s² (inward) from the great attractor. -- BenRG (talk) 12:17, 11 June 2015 (UTC)

Sorry, my numbers were wonky—now improved. I doubled the acceleration from Λ because it applies to both objects equally, whereas the Great Attractor's attraction is one-way (it being much more massive than the Milky Way). -- BenRG (talk) 18:39, 11 June 2015 (UTC)

Laniakea Supercluster is not gravitationally bound, it is clear from the discovery paper. Ruslik_Zero 17:35, 11 June 2015 (UTC)