A more general note about plastics.
I see three main issues:
(1) Do plasticizers leach out of plastics? Yes, I think there are strong evidence for this. Google around. What I've read so far makes sense.
(2) Are these plasticizers harmful? This is harder to answer. The amounts that do leach out are tiny, and probably not too harmful in the short term, though the jury's still out on possible harmful effects from long-term dosage. There is also the extent of harm to consider; toxicology studies examine the obvious and extreme effects of a toxic compound, for example, if a compound causes death or cancer, and the lethal dosage. But just because something doesn't kill you doesn't mean it can't make you chronically sick.
(3) Can plastics be avoided? The practical question. I think it's hard to completely avoid plastics, though some do, and I'd think it makes sense, and is much easier, to prioritize the plastics to avoid. Plus, plastics are really useful in many capacities.
Recently, I've been trying to minimize usage of plastics, especially as food containers. The rate of plasticizer leach is greatest when the plastic is heated, which makes sense, so while I'm still carrying my cold lunch to work in a plastic container, I've stopped microwaving my lunch in that same container but instead transfer it to a ceramic bowl.
I've also read that plasticizers leach best into high fat foods, which also makes sense. For example, pthalates are alkyl esters and are highly soluble in hydrophobic solvents. Finally, not all plastics are the same. Some either contain more toxic plasticizers or maybe higher concentrations (and hence a higher leach rate), and studies have looked into this (as soon as I can find the original research that showed this, I'd link it). Some plastics to avoid include #3 (PVC, or poly vinyl chloride), #6 (PS, or polystyrene), #7 ("other," often polycarbonate), where the numbers refer to the plastic recycling numbers in the tri-arrow triangle.
Along the lines of not all plastics are the same, specific plastic water bottles like Nalgene are better than those 'singe-use' plastic bottles. At work, I've thrown away the 'single-use' plastic bottle I re-used over and over again to hold water and now I use a glass juice bottle (free, after a seminar that provides refreshments). The latest fad now, after the reusable plastic Nalgene bottle (a little bling), is the aluminium Sigg bottle (even more bling-bling), but it's all pretty consumeristic I feel. Besides, I'm not sure aluminum is perfectly safe as well.
I still use a lot of plastic containers in the kitchen, such as yoghurt or ice-cream tubs to store dry foodstuffs. I would gradually make the transition to replace these plastic containers, but small steps first.
From an environmental viewpoint, it's good to also minimize use of plastics. Plastics that are not very recyclable include #3, #4 (LDPE, or low density polyethylene), #5 (PP, or polypropylene), #6 and #7. Given that there are only seven categories and that five of those seven are considered 'not easily recyclable', we should say that it is not easy to recycle plastic and stop patting ourselves on the back when we see that little plastic recycling triangle and 'properly' toss the plastic garbage into the recycling bin.
I see three main issues:
(1) Do plasticizers leach out of plastics? Yes, I think there are strong evidence for this. Google around. What I've read so far makes sense.
(2) Are these plasticizers harmful? This is harder to answer. The amounts that do leach out are tiny, and probably not too harmful in the short term, though the jury's still out on possible harmful effects from long-term dosage. There is also the extent of harm to consider; toxicology studies examine the obvious and extreme effects of a toxic compound, for example, if a compound causes death or cancer, and the lethal dosage. But just because something doesn't kill you doesn't mean it can't make you chronically sick.
(3) Can plastics be avoided? The practical question. I think it's hard to completely avoid plastics, though some do, and I'd think it makes sense, and is much easier, to prioritize the plastics to avoid. Plus, plastics are really useful in many capacities.
Recently, I've been trying to minimize usage of plastics, especially as food containers. The rate of plasticizer leach is greatest when the plastic is heated, which makes sense, so while I'm still carrying my cold lunch to work in a plastic container, I've stopped microwaving my lunch in that same container but instead transfer it to a ceramic bowl.
I've also read that plasticizers leach best into high fat foods, which also makes sense. For example, pthalates are alkyl esters and are highly soluble in hydrophobic solvents. Finally, not all plastics are the same. Some either contain more toxic plasticizers or maybe higher concentrations (and hence a higher leach rate), and studies have looked into this (as soon as I can find the original research that showed this, I'd link it). Some plastics to avoid include #3 (PVC, or poly vinyl chloride), #6 (PS, or polystyrene), #7 ("other," often polycarbonate), where the numbers refer to the plastic recycling numbers in the tri-arrow triangle.
Along the lines of not all plastics are the same, specific plastic water bottles like Nalgene are better than those 'singe-use' plastic bottles. At work, I've thrown away the 'single-use' plastic bottle I re-used over and over again to hold water and now I use a glass juice bottle (free, after a seminar that provides refreshments). The latest fad now, after the reusable plastic Nalgene bottle (a little bling), is the aluminium Sigg bottle (even more bling-bling), but it's all pretty consumeristic I feel. Besides, I'm not sure aluminum is perfectly safe as well.
I still use a lot of plastic containers in the kitchen, such as yoghurt or ice-cream tubs to store dry foodstuffs. I would gradually make the transition to replace these plastic containers, but small steps first.
From an environmental viewpoint, it's good to also minimize use of plastics. Plastics that are not very recyclable include #3, #4 (LDPE, or low density polyethylene), #5 (PP, or polypropylene), #6 and #7. Given that there are only seven categories and that five of those seven are considered 'not easily recyclable', we should say that it is not easy to recycle plastic and stop patting ourselves on the back when we see that little plastic recycling triangle and 'properly' toss the plastic garbage into the recycling bin.
2 comments:
Hi,
What about rubber?
Generally, the common practice is to sterilize the baby bottles through steam.
I don't think they sell glass baby bottles although that would be ideal.
I guess I could try to breast feed as much as possible.
With regards to rubber, I'm not fully certain but I think it's fairly safe. In the sense that, yes, while stuff like sulfur is added to rubber to 'cure' it (vulcanization), it's an irreversible process; sulfur is tightly bound (covalently bound) to the rubber strands. So the added sulfur would not leach out, it's not possible.
I think what you meant was the silicone used for baby bottle nipples. Again, I'm not fully sure. A quick google search shows no safety warning on silicone (or rubber), and in a way, it makes sense. The different properties of various kinds of silicone are achieved through the variation of functional groups or cross-linking, in short, processes that produces tight bonds.
The difference between rubber and silicone, and plastic, is that the first two are 'compounds', while plastic is a 'mixture'. In compounds, stuff added to the silicone or rubber changes the material by binding tightly to it and creating a new material. In plastics, the additives are not as tightly bound. It still changes the properties of the plastic, but does so in a way like lubricating the chain of a bicycle; it's not creating a new compound. After some time, the two components separate.
Yeah, breast feeding is usually better too. I wasn't really following the articles at that point, because I've no baby, but common advice was that there are some plastics that are safer, that do not contain pthalates or BPA. I'm sure there *are* glass bottles, but er, probably expensive and harder to get. Can't quite walk down to the neighborhood shop...
You can do a google search for glass bottles in Singapore (whenever I do a search I tend to get stuff in Canada), but for example, this is very pretty (and pricey).
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