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>Sure, lets all just drink hydrogen peroxide.

I use hydrogen peroxide to disinfect contact lenses. It neutralizes into water and oxygen in the presence of a catalyst. It would do that over a long enough period when exposed to air. I linked a paper in the thread elsewhere that shows the same decay for the chicken washes.

Using peroxide as a lens disinfectant has advantages over other multi-purpose solutions which cause increased corneal staining and are at much higher risk of allergic reactions.




This is about something else. If you are allowed to clean meat that aggressively it usually means what passes as good enough to be sold has a lower standard. Or the other way around: because we in the EU can't use these methods the whole supply chain and quality control has to be much much stricter to deal with this. We can't just dip the thing in chlorine and assume it is clean now.


1. Chlorine isn't used anymore, it's dishonest to claim that it is just as it's dishonest to claim peracetic acid is dangerous or ends up in the end product.

2. Well aware of the problems and concerns with the supply chain in the US, but not treating and dealing with salmonella outbreaks would have measurably worse health outcomes. These problems don't get fixed overnight. I'm fine with those problems being attacked but don't spread FUD about what you don't understand.


1. No, chlorine is still widely used on processed poultry in the U.S. The latest data from the National Chicken Council suggests that it's used in around 10% of chicken processing facilities. This is not a small amount of chicken.

2. There is no evidence that the absence of antimicrobial treatment of chicken carcasses yields "measurably worse health outcomes", as you say. Data collected by USDA and the UK's Food Standards Agency use different criteria for their respective streams, and thus can't offer definitive conclusions, but there don't appear to be large differences in contamination between the American and British systems.

@atoav's comment accurately conveys the official position of EU and UK trade and food safety agencies. I see nothing here to indicate that you have any better understanding of the topic than @atoav.


>1. No, chlorine is still widely used on processed poultry in the U.S. The latest data from the National Chicken Council suggests that it's used in around 10% of chicken processing facilities. This is not a small amount of chicken.

Seems it is still used, I was under the prior understanding that farms were phasing it out as it's far more corrosive and incurs a larger maintenance cost. I can't find anything more on the topic other than that industry page claiming about 10% from 2015.

> 2. There is no evidence that the absence of antimicrobial treatment of chicken carcasses yields "measurably worse health outcomes", as you say.

I have been consistent in claiming that the US supply chain has issues EU/UK don't appear to have. Increased salmonella concentrations are absolutely a health risk and these treatments show large measurable reductions on the level of surface salmonella. There's more than a few studies published in recent years covering outcomes on on chlorine, lactic acid, peracetic acid, SBS, and other rinses. I've never claimed that it's a magic bullet, only that all the data says 'it helps'.


Obviously outbreaks are dealt with here, too.


Tell me more about contacts and corneal staining. This comment is the first I've heard about it.


So the thing you need to know is there's 2 categories of soft contacts that are currently on the market. Hydrogels and Silicone Hydrogels (SiHy). The latter are newer and have become much more common as they are in theory healthier for the eye (they allow more oxygen to pass through). There's some drawbacks though in that the material isn't inherently wettable because silicone is hydrophobic by nature. This means it's a bit more complex to formulate a material and there's some quirks to it, notably it's usually stiffer. This might affect how solutions interact with the surface.

Corneal staining is basically scratching of the outer part of your eye. It is usually asymptomatic but can result in a burning sensation. It was found that the surface of SiHy is affected by what material is used to clean them. This link includes some research and plenty of linked studies: https://contactlensupdate.com/2013/08/14/what-do-we-know-abo... I had a better link that compared various products on the market but I'm unable to find it as this time.


Interesting. That link seems to say they aren't even really confident what staining is, it could just be the fluorescin dye binding to the eye. My friend wears Night & Day (SiHy) and rarely takes them out at night, replaces them maybe every 1-2 months. Mostly no issues or burning, although he did get a corneal ulcer one time, and he has seen increased neovascularization.


Correct, by no means am I claiming it's dangerous to use standard MPS, but I understand the mechanism of action with hydrogen peroxide better and it seems extremely effective. I wear Cooper Biofinity's and rarely take them out, aside from a minor abrasion that caused me not to be able to wear contacts for a month a couple years ago, they've been drama-free.

However, peroxide solution does have some big drawbacks. The better two-stage systems where you add a neutralizing solution to the peroxide when you're about to put the lenses back in I haven't been able to find in the US, and this is the safest gold standard (as you're leaving max disinfection power until right before you get them in your eyes). All that's sold are 1-step systems with a catalyst disk/ring at the bottom of a special case.

While I haven't had issues with the catalyst wearing off of the Clear Care cases, some of the other brands seem to not work as well and if the lens case is left in a sub-60F room, it will not neutralize in time. Honestly, this wasn't something on their documentation and if I wanted to be a pain about it I could probably put a consumer safety claim in. Putting un-neutralized peroxide solution in your eyes is a pretty traumatizing experience, worse than hot sauce. I don't recommend it!

EDIT: I'm not an optometrist/opthamologist, but I'll tell you how I got the background on this stuff: I did a project with some dude on IRC that was like the human bat, he had severe photophobia. We studied quite a bit about the characteristics of various contact lens technologies in preparation for our project. He wanted to acquire tinted contacts and vary the % of opacity. (I'm aware J&J is selling transitions contacts now and unsure of their efficacy but at the time the only options were extremely expensive traditional hydrogels.)

Long story short: We downloaded a bunch of patents and he built a small lab and dyed his own hydrogels using their patented processes. It was a neat and very illegal project, but he got his own sun contacts so he didn't have to live in his cave anymore and I got a ton of semi-useless knowledge.




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