It may not have ever occurred to you (as it really didn't to me) that health considerations could be a factor in choosing cloth or disposables, but it seems to be true. Parents of babies with extra-sensitive skin report reduced diaper rash with cloth in mild cases, and in some cases-- such as the founder of Dearest Diapers-- the baby might have serious skin conditions, like eczema or dermatitis, that nothing will help until the switch is made to cloth.
Why is this? Well, let's stop for a moment to consider the materials we're talking about. Cloth diapers typically have a layer of cotton, bamboo, or hemp (or blends thereof) up against baby's skin. Disposables may have paper or a layer of cotton so thin that it feels papery-- not terribly soft, if you ask me.
On top of that, disposables are often touted as being more absorbent than cloth-- and while this may be true, it's not necessarily an advantage. Because the diaper is more disposable, parents tend to wait longer in between changes, which means that baby is sitting in a diaper containing urine for longer. Even though the diaper absorbs the moisture, the ammonia remains on baby's skin and is another factor that can cause diaper rash or exacerbate other skin conditions, as are the bacteria that begins to form as soon as baby wets or soils the diaper. If left long enough, these can compromise the skin enough to risk serious infection.
So we have to consider chemical exposure-- not something you want to have to worry about for your baby! The majority of disposable diapers involve a number of chemicals in their manufacture. This includes the bleaching of paper pulp, which in turn produces dioxins, which are considered an environmental pollutant by the WHO:
Dioxins are highly toxic and can cause reproductive and developmental problems, damage the immune system, interfere with hormones and also cause cancer. [...] Short-term exposure of humans to high levels of dioxins may result in skin lesions, such as chloracne and patchy darkening of the skin, and altered liver function. Long-term exposure is linked to impairment of the immune system, the developing nervous system, the endocrine system and reproductive functions.Are the levels of dioxins in disposable diapers enough to cause these problems in babies? It's hard to know for sure, though I personally don't care to risk it. It's true that there are unbleached disposable diapers out there, such as Seventh Generation, but they tend to be more expensive than their bleached counterparts, and of course, both are more expensive than cloth diapers in the long run.
Consider, too, exactly why those disposables are so absorbent: a little something called sodium polyacrylate. This is the absorbent, granular polymer found inside disposables, that is capable of absorbing as much as 200-300 times its mass in liquid. You can often see the little gel "crystals" on a baby's skin when changing him out of a wet disposable. The problem here is that sodium polyacrylate can have an overly drying effect on baby's skin, leading to further diaper rash. It's also worth nothing that sodium polyacrylate was once included in tampons, but was removed from them in 1985 following links to toxic shock syndrome (TSS). No cases of TSS have been reported stemming from babies wearing disposable diapers (most likely due to the fact that the diapers are worn externally, while tampons are used internally) but again, it's still not something I'd really like to have against my baby's skin.
In addition, disposable diapers often incorporate dyes, fragrances, and plastics-- none of which I really want on my baby's most sensitive area. At least one study even links these things to an increased risk of asthma.
In the interest of fairness, let's look at the other side of the health question: do cloth diapers have any of these health concerns, or other ones? From the materials standpoint, the only concern I can think of would be the possibility of pesticides in non-organic cotton. However, the processing of cotton into fabric removes any pesticide residues.
It's true that poorly laundered cloth diapers can have a build-up of bacteria and ammonia which can lead to skin irritations for baby; it's also true that leaving a baby too long in a cloth diaper (just like with disposables) can lead to diaper rash. The bottom line is, if you change your baby as often as you should, and know how to wash your diapers, the incidence of skin irritations for cloth-diapered babies should be much lower.
So what's the takeaway? There are those who say that disposables are not worse for a baby's skin and health than cloth-- that the dioxin levels are negligible, that sodium polyacrylate has been proven non-irritating and safe, and so on. In my personal opinion, as with any case of a product with added chemicals vs a product without them, I prefer to err on the side of caution. Especially when it concerns my only son!
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