 Hey everybody, Dr. O. This video we're going to talk about the heavy metals and how they chemically control microbial growth. So here we see the heavy metals. We have mercury, silver, copper, nickel and zinc. So how they actually work is first of all you're going to see a term often used that says they have an oligo dynamic action. Oligo basically means a few or several. So what that means is a very small amount of heavy metals can have an antimicrobial activity. Oligo dynamic activity just tells you just takes up little tiny bit of these metals to actually accumulate in microbial cells and end up killing them. So how they work, the ions of these metals will actually bind to proteins, specifically the sulfur containing amino acids of these proteins. So by binding to these proteins they can either denature them, which will cause them to unravel and lose their shape or can inhibit their functions which would inhibit enzyme activity. So basically turning off enzymes, binding up proteins and denaturing them, that's how they work. So they work very, very effectively. All right. So here we just see the periodic table. And again you can see mercury, silver, copper, nickel and zinc being your heavy metals. All right. So let me give you some examples. So let's go down the list here. So first we have mercury. I mean mercury used to be used a lot in the past until we realized how neurotoxic it was. Like if you ever want to see a neuron die, shrivel up quickly, just put some mercury on it. So mercury, maybe you've heard the term mad as a hatter, you know, people being exposed to mercury having neurological disorders. So mercury super effective, but you're not going to see many uses because it is so neurotoxic, like extremely neurotoxic. Mercury chloride would be one example though. It can prevent mildew in paint. So that would still be one example. Silver, silver's probably my favorite example. You've got silver nitrate or like drops that can be put in baby's eyes to prevent eye infections, especially if mom has gonorrhea. Silver has a huge history. You know, they used to put like silver coins in milk containers to preserve the milk for a while. People talk about being warmer, the silver spoon in your mouth and potentially actually being exposed to the silver from true silverware. Could have had some antimicrobial activities. Some people even say this is why people in wealthy families were less likely to die during the plagues, but obviously they were less likely to be malnourished. And I think the main reason that less of them died was when these plagues started they got out of town and went to their cottages and stuff like that. But it doesn't take anything away from silver. So silver nitrate drops, your silver sulfidiazine that can be used on burns that you have wound dressings with silver in them and these types of things. Silver can also be combined with antibiotics and make them way more effective. So silver, super important example. So silver nitrate, silver sulfidiazine, silver all over the place. Specifically, I was talking about the eye infection with newborns. That would be ophthalmoneonatorum, which is an eye infection that a baby can get if they get a gonorrheal infection from their mom during delivery. All right. So that's silver copper. So copper sulfate is used primarily as an algaecide, so you're going to see like fish tanks and these types of things. So copper is effective. Then nickel and zinc, not as many examples with nickel, but with zinc you've got zinc chloride is going to be found in some of your mouth washes. Zinc oxide, like I know like the stuff we used on Oliver's hind hem when he was a baby had zinc oxide in it. I think some of your dandruff shampoos have zinc oxide in it. And I believe like calamine lotion does as well. So those are some examples of the heavy metals and they're very antimicrobial because of how they bind up to proteins and stop enzymes from functioning. So I hope this helps. Have a wonderful day. Be blessed.