Everything natural decomposes. It rots and/or grows mold, and eventually returns to the earth in the universe’s greatest recycling plan. This is awesome for long-term sustainability, but not so great when you want to make something now and use it later or kill something now (plant or animal) and eat it later. Hence humans have been working on preservative methods since ancient man. Good preservation inhibits mold and stops microbes from decomposing your goods–whether it’s food or the wood siding of your house. (Paint is a preservative for wood.)

There are several actions we can take to stop or slow biodegradation. The most common everyday preservation method is chilling by putting something in the refrigerator (short term) or freezer (long term). Smoking (jerky), drying (raisins), vacuum-sealing (i.e. eliminating air contact, like canning), pasteurization (heating to kill microbes and yeast), and fermentation (beer) are also actions taken to make something keep without spoiling.

Because natural beauty products aren’t smoked, dried or vacuum sealed (at least after they’re opened), it’s recommended to use them up quickly, just like you would any food product. In fact, if they contain water or dairy you need to use them within a few days. (If a friend gives you homemade liquid/cream lotion as opposed to lotion bars, ask them how long you have before it goes bad as these are water based!) Products composed of shelf-stable oils can last longer, but, again, not indefinitely–just like your olive oil; it can sit in the pantry for awhile, but not for the next five years. Like food, you can keep natural cosmetics in the refrigerator to slow decomposition.

If you want a little more flexibility (or security), you need preservatives! It’s important to ensure your preservatives are antifungal (prevent fungus), as well as protect against a wide range of mold and bacteria. Most preservatives don’t do all these things, hence a product needs more than one kind to stay shelf-stable. I’m not going into which of these preservatives does what as that’s way above my knowledge-base.

Natural Preservatives

  • Salt (sodium chloride)

  • Alcohol

  • Sugar

  • Vitamin E

  • Rosemary

  • Vinegar

  • Castor Oil

  • Vitamin C

  • Citric Acid – Citric acid was first discovered in the 8th century from citrus fruit. Now it’s typically made by feeding sugar to a mold called Aspergillus niger, so it’s sort of synthesized. Then again, alcohol and vinegar aren’t exactly pulled off a tree, either. Most manufacturers will still claim these as natural ingredients.

  • Sulfites – (Sulfur dioxide, Potassium bisulfite, potassium metabisulfite, sodium bisulfite, sodium metabisulfite, or sodium sulfite) Wine-making naturally creates these, but winemakers almost always put more in to give wines a longer shelf life. (So called “sulfite free wines” are not truly sulfite free, they just don’t have additional sulfites added.) Sulfites are also added to dried fruit and some fishing vessels add it to their shrimp on the boat–a way of using sulfites that doesn’t have to be listed on an ingredient label. I had a hard time deciding whether to put sulfites here or on the synthetic list, but since it does naturally occur in wine-making I left it here. But sulfites are an example of how natural is not always a guarantee that it’s safe. Sulfite sensitivity is a common problem, estimated at affecting up to 1% of the population.

  • Grapefruit Seed Extract – I’ve read some questionable things about this, including whether or not it should be considered natural. It’s made from grapefruit seed and pulp combined with glycerin (a soap byproduct<LINK>), but apparently is regularly contaminated with parabens and other synthetic preservatives.

Sometimes natural won’t cut it. If you need a product to make it across the world by freight and then sit on a grocery shelf for six months before people buy it and store it in their pantries for a year or more, that’s a lot of preservation. Enter synthetics. These are frequently the things you hear about being pulled from market for cancer-causing properties or general bizarre health concerns that only happen after regular use. Like I’ve mentioned before, a lot of the problems with these come not with one use–our bodies are pretty good at handling a one-off–but with daily showering, shampooing, toothbrushing, deodorant wearing, makeup applying, lotion slathering,  “oh and then I ate some in my food today” habits.That’s a lot of preservatives.

  • Parabens – named things like methylparaben (E number E218), ethylparaben (E214), propylparaben (E216), butylparaben, heptylparaben (E209), etc. You might’ve gotten a chain email or seen headlines about how these are going to kill us all. That has not been scientifically proven. They have been found in breast cancer tumors. Some react with UVB causing skin damage. They all have estrogenic properties, leading some scientists to think they can cause early onset puberty in young girls. The FDA however, while acknowledging that parabens are estrogenic and show up in tumors, thinks they’re fine. To be fair, here’s an alternate viewpoint well argued by a cosmetic company who seems quite ethical.

  • Propylene glycol – also a solvent and de-icer. The big danger with this is that it inhibits your skin’s protective abilities, allowing more gunk past your natural defenses and into your bloodstream. Things that normally your skin would keep out are suddenly able to penetrate in the presence of propylene glycol.

  • EDTA - ethylenediaminetetraacetic acid; also used as a food preservative. EDTA comes in several varieties, with a chemical name in front of the EDTA to tell you what kind it is. It is cytotoxic (damaging to cells, like snake venom) and genotoxic (damaging to genetic material, i.e. might turn you into an X-Man! Not really. But it is genotoxic). It’s also been shown to cause reproductive and developmental effects when taken orally. WebMD has a fun list of side effects. Despite this, researchers say that the level of exposure through cosmetics is still below the toxic threshold, so I suppose it’s okay that we put EDTA in everything from food to soap. Add to that, they’re not entirely biodegradable.

  • Isothiazolinones – like methylchloroisothiazolinone. From what I can tell, these are not that bad. They can be a skin irritant, but you have to be allergic. They are harmful in large doses, but apparently they take a very small dose to be effective. They also biodegrade, although they can be bad for aquatic ecosystems. Others disagree with me, but if you’re going to go synthetic and you’re not allergic, these seem far less offensive than most. Plus they’re fun to say, so bonus points in my book! ;)

  • Formaldehyde – if it’s good enough for a dead body…Actually, these preservative chemicals release formaldehyde, which, as we all know, preserves things. Unlike a lot of other ingredients which have names that sound alike, these names are all over the map. For example: quaternium-15, imidazolidinyl urea, diazolidinyl urea, DMDM hydantoin and hydroxymethylglycinate are all formaldehyde releasing preservatives. As you can probably tell, I have a hard time separating my association with dead things from this preservative, so I’ll leave you to research these on your own and determine if you want it in your daily regime.

  • BHA and BHT – (butylated hydroxyanisole and butylated hydroxytoluene) – Again these don’t have definitive yay/nays, but (also again) they are one of the ones used not only in cosmetics but in food so you can bombard your body in multiple ways. These have been possibly linked to endocrine disruption (hormone disruption) and tumor increases. The United Nations lists it as bioaccumulative in marine life and OSPAR considers it a harmful substance to aquatic ecosystems, although they believe it is currently adequately controlled, at least from an environmental perspective. Canada has it on its list of chemicals to reevaluate the status of, California requires it to be listed as a possible carcinogen on product labels, and the European Union does not allow its use under the “fragrance” label.

  • Triclosan – This one is used in many things, including hand sanitizers, and is suspected of contributing to the evolution of “super-bacteria” that resist antibiotics. In addition to cosmetics, it’s used in plasticware and textiles. Triclosan is easily absorbed through the skin, and a 2004 study by the CDC found it in the urine of 74.6% of the over 2000 people tested. It’s considered toxic to aquatic life as well as bioaccumulative and persistent–it doesn’t biodegrade. The ubiquity of this chemical is what has most people worried, as it’s found in everything from mouthwash to hand sanitizer to deodorants to dishwashing soap to socks and underwear.

  • Nitrites/Nitrates – These are almost guaranteed to exist in cured meats, as without them meats turn gray instead of that nice pink we’re used to. Nitrites are mildly toxic, which is why curing salts (which are fortified with nitrites) are dyed pink so people don’t accidentally use them in regular cooking. Nitrites have been added to cured meats since the early 1900s. The biggest concern regarding them is usually carcinogenic nitrosamines. These are created from nitrites either when the meat is burned or they can be converted with the introduction of acid…like you have in your stomach. Ascorbic acid (Vitamin C) stops this conversion from happening. Since the 1970s, ascorbic acid has been included in meat manufactured in the US. Nitrites can trigger migraines in some people.

This is only a small listing of all the preservatives out there (particularly food preservatives), but I tried to discuss the most prevalent ones–particularly those causing the most controversy over safety. As I said at the beginning, preserving food and cosmetics is necessary for our health–unless you plan on concocting your own makeup, shampoo, deodorant, and everything else you use from scratch every morning. I’m not that dedicated. ;)

What are your thoughts on preservatives?

~ Featured Image: Autumnal Leaf by ceridwen