Could commonly used cookware and dishware be contaminated?

[kenny1999]

There is a long story behind but since it is not related to either Chemistry or science so I am not going to explain it here. Fact is, I have a pile of dishware and cookware made of all kinds of materials commonly used for dishware/cookware e.g. ceramic, stainless steel, polypropylene, wood etc. but these dishware and cookware were dirty and had not been cleaned for at least 1 year. Some of them were soaked in dirty water and some of them were left dry but you can imagine that all kinds of bacteria and household insects should have stayed around these dishware and cookware for a long time.

My question is - By common sense, I think it's still safe to use them after cleaning them up with kitchen detergent or boiling water thoroughly. But is it true? Could bacteria or dirty water or anything unwelcome be slowly absorbed into these materials because of the long time? Are these dishware and cookware still safe to use after they are cleaned?

Thanks.

[Sensei]

50 minutes ago, kenny1999 said:

But is it true? Could bacteria or dirty water or anything unwelcome be slowly absorbed into these materials because of the long time? Are these dishware and cookware still safe to use after they are cleaned?

Generally speaking, yes.
The only thing that can make them dangerous is radioactivity.
A few hand-wash cycles, then put them in the dishwasher for a few hours and they will be clean.

High temperatures are lethal to most organisms. Basically, their organic compounds decompose or degenerate..

https://en.wikipedia.org/wiki/Extremophile

 

Edited October 26, 2023 by Sensei

[exchemist]

2 hours ago, kenny1999 said:

There is a long story behind but since it is not related to either Chemistry or science so I am not going to explain it here. Fact is, I have a pile of dishware and cookware made of all kinds of materials commonly used for dishware/cookware e.g. ceramic, stainless steel, polypropylene, wood etc. but these dishware and cookware were dirty and had not been cleaned for at least 1 year. Some of them were soaked in dirty water and some of them were left dry but you can imagine that all kinds of bacteria and household insects should have stayed around these dishware and cookware for a long time.

My question is - By common sense, I think it's still safe to use them after cleaning them up with kitchen detergent or boiling water thoroughly. But is it true? Could bacteria or dirty water or anything unwelcome be slowly absorbed into these materials because of the long time? Are these dishware and cookware still safe to use after they are cleaned?

Thanks.

Agree with @Sensei. In fact I have read that wood in particular is a curiosity. Studies have apparently been done comparing synthetic and wooden chopping boards and worktops which show, counterintuitively, that wood, irregular, absorbent and grainy thought it is,  retains fewer bacteria and fungi on the surface than synthetic surfaces. This is attributed to natural antiseptic properties of the material. The takeaway from the article I read was that rather than worrying too much about worktops and boards, which you can just wipe down each day, the places to watch in your kitchen for pathogens are the dishcloths and the sponges and cloths used for washing the dishes. Change and wash those very regularly. 

 

[mistermack]

1 hour ago, exchemist said:

Change and wash those very regularly. 

I don't get the logic behind this sort of advice. I never change the old rags I use to wash dishes, nor do I wash them. 

If you wash dishes and then rinse them with clean water, and leave them to drain dry, how do bugs on the washing cloth matter? In any case, the human body is equipped to cope with small numbers of bacteria etc. It's when they are allowed to multiply that they begin to become a threat. You need a certain amount of encounters with bacteria to keep your immune system ticking over. If you are immune compromised, it might be more important to avoid small amounts of bacteria.  

I like a wooden chopping board. For some reason it's much more satisfying using wood than plastic etc, even though I have both kinds. I think the wood is easier on the knife blade, especially softwood. 

[kenny1999]

Thanks all above. Is it true that dishware or cookware made of wood is more likely to be unsafe after being left uncleaned, dirty (or even soaked in dirty water) for a very long time because they look like to be more porous than other materials?

[exchemist]

10 hours ago, mistermack said:

I don't get the logic behind this sort of advice. I never change the old rags I use to wash dishes, nor do I wash them. 

If you wash dishes and then rinse them with clean water, and leave them to drain dry, how do bugs on the washing cloth matter? In any case, the human body is equipped to cope with small numbers of bacteria etc. It's when they are allowed to multiply that they begin to become a threat. You need a certain amount of encounters with bacteria to keep your immune system ticking over. If you are immune compromised, it might be more important to avoid small amounts of bacteria.  

I like a wooden chopping board. For some reason it's much more satisfying using wood than plastic etc, even though I have both kinds. I think the wood is easier on the knife blade, especially softwood. 

OK fair enough I wrote that badly. The changing and washing I intended to refer to dishcloths, not to the utensils used to wash the dishes in the sink. If those utensils are absorbent they need to be allowed to dry, or they will grow bugs and stink. 

[mistermack]

4 hours ago, exchemist said:

OK fair enough I wrote that badly. The changing and washing I intended to refer to dishcloths, not to the utensils used to wash the dishes in the sink. If those utensils are absorbent they need to be allowed to dry, or they will grow bugs and stink. 

Ah right. We call those tea towels in Gloucester. 'Dishcloths' is reserved for the wet washing-up cloths. I know lots of people will dry dishes with a tea towel, rather than letting them drain dry,  but I've never seen the point, unless you have a too-big pile of wet washing up and need the space. If a few bacteria is a worry, then the used tea towel is the less hygienic option. But I'm sure it's not that critical. You need a certain dose of bacteria to make you ill, and I'm sure you'll never get that from a plate that looks reasonably clean. And cooking pots and pans are even less critical, as you will generally be heating them up and killing any bacteria that are lurking on the surface. 

[Sensei]

15 hours ago, mistermack said:

I don't get the logic behind this sort of advice. I never change the old rags I use to wash dishes, nor do I wash them. 

..and you don't change your socks..

 

[mistermack]

4 minutes ago, Sensei said:

..and you don't change your socks..

I don't need to, I wash my feet every month. 

[Sensei]

15 minutes ago, mistermack said:

I don't need to, I wash my feet every month. 

..anti-Russian agents have an easy job.. they just have to follow the dogs.. following the smell..

 

https://en.wikipedia.org/wiki/Footwrap

 

Edited October 27, 2023 by Sensei

[mistermack]

4 minutes ago, Sensei said:

.anti-Russian agents have an easy job.. they just have to follow the dogs.. following the smell..

They can try, but your spoilt western dogs are too fat and slow to keep up.  

[Sensei]

1 minute ago, mistermack said:

They can try, but your spoilt western dogs are too fat and slow to keep up.  

..to a certain level, I agree..

ps. I appreciate the sense of humor..

 

[mistermack]

4 minutes ago, Sensei said:

ps. I appreciate the sense of humor..

As I always say to Americans, you don't need to be able to spell humour to appreciate it. 😄

[Sensei]

Just now, mistermack said:

As I always say to Americans, you don't need to be able to spell humour to appreciate it. 😄

..the last time I saw an American IRL it was at the Casino and it was 10+ years ago..

We played black jack. It was a fun time, not like today..

[exchemist]

1 hour ago, mistermack said:

Ah right. We call those tea towels in Gloucester. 'Dishcloths' is reserved for the wet washing-up cloths. I know lots of people will dry dishes with a tea towel, rather than letting them drain dry,  but I've never seen the point, unless you have a too-big pile of wet washing up and need the space. If a few bacteria is a worry, then the used tea towel is the less hygienic option. But I'm sure it's not that critical. You need a certain dose of bacteria to make you ill, and I'm sure you'll never get that from a plate that looks reasonably clean. And cooking pots and pans are even less critical, as you will generally be heating them up and killing any bacteria that are lurking on the surface. 

Sure, a lot depends on how many people have been fed and how much dirty crockery and pans have been created. Like you, I let things drain and dry on the rack, when there are only one or two of us. If it’s a big group that may not be feasible, esp. if there are glasses as well - they really do need drying or they get streaks.  But the tea towels or dishcloths also get used for other purposes in my kitchen, e.g for wiping damp hands while cooking. 

[kenny1999]

Hi, I thought about starting a new thread but I think it's the best to continue my question and the discussion here because it's very much related.

I just happen to know that everything, even if it's logically considered to be resistant to water, e.g. polypropylene, chances are it would absorb some water over time. In that case, suppose I have got some very dirty water (e.g. filled with all kinds of dirty stuff, rotted food, bacteria, or even urine etc) that stays in a polypropylene container for a very long time, would the container absorb some of those dirty water over time and make it less safe to use even if the container is later on thoroughly cleaned, washed and rinsed with kitchen detergent and water? The same question applies to other commonly used materials for dishware and cookware e.g. ceramic, stainless steel, etc.

[Externet]

Hi.

Metallic wares will be safe for food use after visiting an oven at 200C+.  Then boiling water poured in wooden/plastic wares for a while should produce same results.  Discard whatever makes you feel uncomfortable. 

Nothing survives in plain gasoline either, with no need for a match... Odor would take several days to fade.

[StringJunky]

On 10/27/2023 at 1:56 PM, mistermack said:

Ah right. We call those tea towels in Gloucester. 'Dishcloths' is reserved for the wet washing-up cloths. I know lots of people will dry dishes with a tea towel, rather than letting them drain dry,  but I've never seen the point, unless you have a too-big pile of wet washing up and need the space. If a few bacteria is a worry, then the used tea towel is the less hygienic option. But I'm sure it's not that critical. You need a certain dose of bacteria to make you ill, and I'm sure you'll never get that from a plate that looks reasonably clean. And cooking pots and pans are even less critical, as you will generally be heating them up and killing any bacteria that are lurking on the surface. 

'Tea towels' here too, East Midlands. IIRC you shouldn't dry them with a cloth if hygiene is imperative; cross-contamination risk. 

Edited November 16, 2023 by StringJunky

[exchemist]

On 11/11/2023 at 8:17 PM, kenny1999 said:

Hi, I thought about starting a new thread but I think it's the best to continue my question and the discussion here because it's very much related.

I just happen to know that everything, even if it's logically considered to be resistant to water, e.g. polypropylene, chances are it would absorb some water over time. In that case, suppose I have got some very dirty water (e.g. filled with all kinds of dirty stuff, rotted food, bacteria, or even urine etc) that stays in a polypropylene container for a very long time, would the container absorb some of those dirty water over time and make it less safe to use even if the container is later on thoroughly cleaned, washed and rinsed with kitchen detergent and water? The same question applies to other commonly used materials for dishware and cookware e.g. ceramic, stainless steel, etc.

No. Bacteria are too large to penetrate into the material. But it may smell, from chemical compounds absorbed or adsorbed on the plastic. I find plastic food containers do pick up a taint if used for anything with strong smell. And colour, sometimes: tomatoes and turmeric especially. 

[kenny1999]

On 11/17/2023 at 2:17 AM, exchemist said:

No. Bacteria are too large to penetrate into the material. But it may smell, from chemical compounds absorbed or adsorbed on the plastic. I find plastic food containers do pick up a taint if used for anything with strong smell. And colour, sometimes: tomatoes and turmeric especially. 

I understand, but for the material that we know that they are highly impermeable to water, e.g. plastic, glass, but they still have very low water absorption rate, how do those water molecules penetrate into the material?

[exchemist]

1 hour ago, kenny1999 said:

I understand, but for the material that we know that they are highly impermeable to water, e.g. plastic, glass, but they still have very low water absorption rate, how do those water molecules penetrate into the material?

Who mentioned water molecules?

[mistermack]

Certain plates that look impermeable might not be. Plates and cups that are glazed china can look ok, but the glaze has micro cracks that allow penetration, and liquids can stain the originally white china. Some older china is a maze of cracks on the surface, especially if you look under a microscope. 

I don't think it matters in the slightest, apart from a  staining and presentation point of view. The quantities you are likely to encounter are so tiny. 

But if you're worried you can buy glass plates, cups and saucers, or coloured glass that looks just like china. 

[kenny1999]

11 hours ago, mistermack said:

Certain plates that look impermeable might not be. Plates and cups that are glazed china can look ok, but the glaze has micro cracks that allow penetration, and liquids can stain the originally white china. Some older china is a maze of cracks on the surface, especially if you look under a microscope. 

I don't think it matters in the slightest, apart from a  staining and presentation point of view. The quantities you are likely to encounter are so tiny. 

But if you're worried you can buy glass plates, cups and saucers, or coloured glass that looks just like china. 

Nope, I am not talking about cracks or imperfect surface, I mean scientifically there is also a very low absorption rate for kinds of impermeable materials e.g. polypropylene, glass, even if it's made and finished perfectly. How could that happen?

[exchemist]

1 hour ago, kenny1999 said:

Nope, I am not talking about cracks or imperfect surface, I mean scientifically there is also a very low absorption rate for kinds of impermeable materials e.g. polypropylene, glass, even if it's made and finished perfectly. How could that happen?

You state this as if it were a fact. What is your source for this idea? 

[kenny1999]

1 hour ago, exchemist said:

You state this as if it were a fact. What is your source for this idea? 

Plenty of such information if you simply do a search on Google with keywords, "water absorption rate polypropylene".

One example:

https://omnexus.specialchem.com/polymer-properties/properties/water-absorption-24-hours#Values

 

Edited November 20, 2023 by kenny1999