This is not a recommendation to discard isothiazolinones or other allergenic preservatives; they are a necessity but should be used with caution.

Michael just lumps everything together is incorrect. Because the chloro is sold with the non-chloro versionat a 3 to 1 ratio, he assumes boith are the cause. As the pure chloro is not a commercial product, the test kist use the mixture. The pure methylisothiazolinone is a commercial product and is recommended for leave on applications. It needs a anti-fungal agent with it to give complete protection.

PS. Drowning is not caused by high level of exposure to water. Drowning is caused by increased CO2 levels in the blood that forces one to inhale water.

Here’s another link to the work related to the bacteria found growing in hairspray. It is not on the hair but in the concentrate. I have no idea how it survived the alcohol exposure. http://www.biomedexperts.com/Abstract.bme/18319473/Microbacterium_hatanonis_sp_nov__isolated_as_a_contaminant_of_hairspray

1. HA sucks water out of the air and becomes wet. If you put dry HA on a dish, in about 30 minutes you would have a puddle of water. It is a very hygroscopic material, one which attracts moisture from the atmosphere. If not protected from contact with the atmosphere (by being stored under vacuum or under a dry gas) some hygroscopic materials will eventually attract so much water that they will form solutions.

2. Then this water wets or hydrates the outer skin proteins. This weakens the proteins and loosens the protective skin barrier.

The weak skin barrier allows bacteria, viruses, and allergens to pass through the skin. Often famous young actors in their late 20s have a very spotted skin (you often see this on a large screen) from skin barrier damage from heavy use of make up and make up removers.

3. The wet proteins slow keratin production. The signal for the skin to send up new keratinocytes to the surface is a dryness in the proteins in the top of the skin. So skin is replaced slower and damage accumulates.

4. Many years ago, women used Cold Creams to keep their faces moist when they went to bed. If you have seen “I Love Lucy” or old movies, you have seem women with these white creams all over their face. But they ended up with horrible wrinkles as time went by because their skin had been keep too wet.

5. There is the idea of a limited cell life but many cell biologists doubt if this is correct. Many cells line that die in about 40 generations will live very long – such a 200 generations – as normal diploid, cancer-free cells if they are given supplemental growth factors such a fibroblast growth factor, GHK, and other hormones. No one knows how long cells can live because very long cell culture experiments are very expensive.

The body also makes stem cells – even in adults – that can keep setting up new cell lines.”

So is HA good or not for the skin?

Parabens also show weak activity against some Gram negative bacteria. They only function when dissolved in water. Exceeding the water solubility is a waste of money.

Formaldehyde donors rarely dissociate in water. What causes the release is the breaking of the Nitrogen to Carbon bond: -N-CH2-OH.They are weakest aginst molds. Gulteraldehyde does not breakdown to formaldehyde. It is a very strong skin senistizer and is almost never used in cosmetics due to this and is bad odor.

Quats function best above a pH of 7. Most are very more at any pH against pseudomonas.

Ther is a debate if propylene glycol is really anti-microbial or is it due to its lowering of water activity. Either way the levels that show inhibition are much higher than those used in cosmetics as above 10% it causes a “burning” feeling to skin.

Methyliosthaizoline is very weak against mold, the chloro is strongly anti-fungal. The mixture is not recommednded for leave on products.

Chloroacetamide has been found to be unsafe by the CIR. It causes chloroacne.
Zinc prithione do not kill bacteria they are strongly anti-fungal and yeast. The gunig cause dandruff- not bacteria.

As to the hairspray, I have these questions-did the bateria grow in the hair or in the actual spray? How much alcohol was in the hairspray?