Pads, liners and tampons are made from a mix of absorbent fibers, plastics and adhesives, layered to soak up fluid, keep it away from the skin and hold their shape for a few hours at a time. The core absorbent material is usually cellulose (wood pulp) or cotton, sometimes blended with superabsorbent polymers similar to those used in diapers, while the outer layers, liners and packaging are typically polyethylene, polypropylene or rayon. What varies between brands and product lines is the ratio of these materials, whether the fibers are organic cotton or conventional wood pulp, and which finishing chemicals – fragrances, dyes, adhesives – are added on top.
This matters because period products sit directly against sensitive skin and mucous membranes for hours at a stretch, several days a month, for decades. Understanding the layers of a pad or the fibers inside a tampon helps you compare products on something more useful than marketing copy, and it gives you a starting point if you are trying to work out why a particular brand causes irritation while another doesn't.
The layers inside a typical pad
A disposable pad is built like a small sandwich, and each layer has a specific job:
- Top sheet – the part that touches the skin, usually a soft, perforated nonwoven material made from polypropylene or polyethylene. Its job is to let fluid pass through quickly while staying dry to the touch.
- Absorbent core – a mix of fluffed wood pulp (cellulose) and, in most mainstream pads, superabsorbent polymer beads or fibers that lock moisture in and prevent it from shifting or leaking sideways. Cotton-based pads replace some or all of the wood pulp with cotton fiber.
- Distribution layer – a thin layer that spreads fluid across the pad so the whole core is used rather than just the center.
- Back sheet – a leak-proof plastic film, typically polyethylene, that keeps fluid from soaking through to underwear.
- Adhesive strips and wings – pressure-sensitive glue that holds the pad in place, plus a release paper that is peeled off before use.
Overnight and heavy-flow pads simply add more absorbent core and a longer back sheet; the basic construction stays the same. Reusable cloth pads swap the disposable layers for washable fabric – often cotton, bamboo viscose or a synthetic wicking layer – stitched together with a waterproof backing, closed with a snap instead of adhesive.
Panty liners: a thinner version of the same idea
Liners follow the identical layered logic as pads but scaled down – a thin top sheet, a light absorbent core (sometimes just a few sheets of tissue-like pulp), and a slim plastic backing, all designed for light spotting, discharge, or as backup with a tampon or menstrual cup rather than for menstrual flow on its own. Because the absorbent core is so thin, liners rely more heavily on the top sheet material for comfort, which is part of why fragrance-free, breathable options are worth looking for if you notice any irritation with scented versions. If itching or unusual discharge shows up alongside liner use, it is worth reading about what a pH test shows before assuming the liner itself is the cause, since vaginal pH shifts have several possible triggers.
What tampons are made of
Tampons are compressed cylinders of absorbent fiber with a withdrawal string sewn or bonded through the center, and usually an applicator made of plastic or compressed cardboard.
The absorbent fiber itself falls into a few categories:
- Cotton – either conventional or certified organic, used alone or blended with rayon.
- Rayon (viscose) – a fiber manufactured from wood pulp cellulose. It absorbs fluid efficiently and is common in mainstream tampon blends, often mixed with cotton.
- Cotton-rayon blends – the most common construction in mass-market tampons, balancing absorbency with cost and manufacturing consistency.
Applicators are either plastic (smooth, sometimes with a rounded tip), compressed paperboard (a cardboard-style applicator, often marketed as a lower-plastic option), or absent altogether in digital (non-applicator) tampons that are inserted with a finger.
One detail worth understanding is the bleaching process used on cotton and rayon fibers. Older elemental chlorine bleaching could leave trace dioxin residues; most manufacturers today use elemental chlorine-free or totally chlorine-free processes, which significantly reduce that concern, though it is reasonable to check a brand's own disclosures if this matters to you rather than assuming every product uses the same method.
Comparison table: materials at a glance
| Product | Core material | Outer/backing layer | Common additions | Typical wear time |
|---|---|---|---|---|
| Disposable pad | Wood pulp cellulose, sometimes with superabsorbent polymer, or cotton | Polyethylene back sheet, polypropylene top sheet | Adhesive strips, wings, fragrance (optional) | 4–6 hours, longer overnight |
| Panty liner | Thin wood pulp or cotton layer | Polyethylene film backing | Adhesive strip, fragrance (optional) | Variable, changed as needed |
| Reusable cloth pad | Cotton, bamboo viscose, or synthetic wicking fabric | Waterproof fabric laminate (e.g., PUL) | Snap closure | 4–8 hours, then washed |
| Applicator tampon | Cotton, rayon, or a cotton-rayon blend | Plastic or compressed paperboard applicator | Withdrawal string, sometimes a light coating | Up to 8 hours, per label guidance |
| Digital tampon | Cotton, rayon, or a cotton-rayon blend | None (finger-inserted) | Withdrawal string | Up to 8 hours, per label guidance |
Figures for wear time are general label conventions, not fixed rules – always follow the specific product's own instructions and change tampons and pads as flow requires, not by the clock alone.
Organic and "chemical-free" claims: what they actually mean
"Organic cotton" on a label refers to how the cotton was farmed – without most synthetic pesticides or fertilizers – and, depending on certification, how it was processed afterward. It does not automatically mean the finished product has no plastic backing, no adhesive, or no fragrance; many organic-cotton tampons and pads still use a plastic applicator or a polyethylene back sheet for leak protection. Reading the full ingredient or material list on the packaging, rather than relying on a single front-of-box claim, is the only reliable way to know what you're getting.
"Chemical-free" is not a meaningful claim in a strict sense, since every material – including organic cotton – is made of chemical compounds. What manufacturers usually mean is that the product is free of a specific list: chlorine bleach residues, added fragrance, dyes, or certain plastics. Look for the specific exclusion named on the package rather than the vague phrase itself.
Certifications worth recognizing
A handful of certification marks show up repeatedly on period product packaging, and each one covers a different, fairly narrow claim:
- Organic certification (such as GOTS or a national organic seal) – verifies the cotton was grown and processed under organic standards.
- OEKO-TEX or similar textile certifications – indicate the finished textile has been tested against a defined list of substances of concern, at set limits.
- Fragrance-free / dye-free labeling – a manufacturer claim rather than a third-party certification in most cases, but still useful information to compare across brands.
- FDA registration (in the US) or equivalent regulatory listing – tampons and pads are regulated as medical devices in several countries, which sets baseline manufacturing and labeling requirements, though it does not amount to an endorsement of any particular brand.
None of these certifications is a guarantee of safety or superiority on its own; they each narrow down one variable. If a specific material sensitivity is your concern – say, a known reaction to a particular adhesive or dye – the certification that addresses that exact substance is the one worth prioritizing, not the certification with the most recognizable name.
What testing has and hasn't found
Independent laboratory testing of period products over the years has looked for a range of substances, including trace heavy metals, phthalates, and volatile organic compounds, largely because these products are used internally or against mucous membranes. Some published testing panels have screened well over a hundred different substances in a single batch of samples – figures in that general range (roughly 117 in one commonly referenced review, though exact counts vary by lab, product line and year) come up in discussions of this kind of testing. It is worth being cautious about how these results get summarized in headlines: detecting a trace amount of a substance is not the same as demonstrating a health effect at that exposure level, and testing methodologies, sample sizes and thresholds vary considerably between studies. For a topic this consequential, it is best to look at findings from established regulatory bodies and peer-reviewed research – bodies such as the US NIH or a country's own health regulator (for example COFEPRIS in Mexico) publish more measured summaries than most consumer news coverage does, and they are a better starting point than a single viral article.
Toxic shock syndrome and tampon safety
Toxic shock syndrome (TSS) is a rare but serious bacterial illness that has been associated with tampon use, particularly with higher-absorbency tampons left in for extended periods. The mechanism involves certain strains of bacteria that can proliferate under specific conditions inside the vagina. This is not a reason to avoid tampons altogether, but it is the reason every tampon package carries the same core guidance: use the lowest absorbency that manages your flow, change tampons regularly (package instructions typically specify a maximum wear time), and never leave one in overnight beyond that window. If you develop a sudden high fever, rash, dizziness or fainting while using a tampon, remove it and seek medical attention promptly rather than waiting to see if symptoms pass – this is a genuine medical emergency, not a case for self-monitoring.
Skin reactions, irritation and vaginal health
Contact dermatitis from pads or liners – itching, redness, mild swelling along the area where the product sits – is usually linked to fragrance, adhesive, or a specific material rather than the core absorbent fiber itself. Switching to an unscented, cotton-topsheet product is a reasonable first step if this happens repeatedly. Recurrent irritation, unusual odor, or discomfort that doesn't resolve with a product switch is worth discussing with a doctor rather than working through every brand on the shelf, since these symptoms can also reflect an infection or a vaginal pH imbalance unrelated to the product itself. The vaginal microbiome is sensitive to a number of inputs beyond period products, and if you're troubleshooting recurring discomfort it may help to also look at what separates a women's probiotic from a standard one, since gut and vaginal flora are sometimes discussed together in that context. For persistent irritation or suspected infection, a doctor's assessment is the right next step before trying at-home remedies such as boric acid suppositories, which carry their own specific cautions and are not appropriate for every situation. Never use a home remedy of this kind without first checking with a healthcare provider, since misuse can worsen symptoms rather than resolve them.
Buying criteria that actually matter
With so many product lines making overlapping claims, it helps to compare pads, liners and tampons on a short list of concrete factors rather than on branding:
- Form and fit – pads and liners come in different lengths, widths and wing designs; tampons come in a range of absorbencies (light, regular, super, super-plus) and applicator styles. The right form depends on your flow and body, not on which product is most heavily advertised.
- Absorbency matched to flow – using the lowest absorbency tampon that comfortably manages your flow reduces both the TSS risk discussed above and the dryness or micro-abrasion that can come from an oversized tampon on a light day.
- Material composition – check whether the core is cotton, wood pulp, or a blend, and whether the product uses a plastic or cardboard applicator, particularly if you are trying to reduce plastic use or have a known sensitivity.
- Certifications relevant to your concern – an organic certification matters most if pesticide exposure is your worry; a textile safety certification matters more if you're concerned about dyes or finishing chemicals. Match the certification to the actual concern rather than collecting the most badges.
- Price per unit or per cycle – rather than comparing box prices, work out the cost per pad or per tampon, since pack sizes and absorbency mixes vary widely between lines. Store pages and price-comparison tools are more reliable for this than any figure quoted in an article, since prices shift regularly – check the current price at the retailer before buying.
- Fragrance and dye content – unscented, dye-free options are generally the safer default choice if you have any history of sensitivity, since fragrance chemicals are a leading cause of contact irritation with these products.
None of these factors override personal comfort and trial. Many people find that the product that works best for them is discovered through a bit of direct comparison rather than through any single specification on a label.
A note on reusable and alternative products
Menstrual cups, reusable cloth pads and period underwear are built from different materials again – medical-grade silicone for cups, layered absorbent fabrics for underwear and cloth pads – and each comes with its own care instructions, wear-time guidance and cleaning requirements. They are not covered in depth here since the construction differs enough from disposable pads and tampons to deserve separate treatment, but the same basic principle applies: check the material list, follow the manufacturer's cleaning and replacement guidance, and stop using anything that causes persistent irritation.
When to talk to a doctor
Period products are simple in construction but they interact with a part of the body that can reflect broader health signals. See a doctor if you notice: irritation that persists after switching to a fragrance-free, cotton-topsheet product; unusual odor or discharge that doesn't track with your normal cycle; a fever, rash or dizziness during tampon use (treat this as urgent); or if your flow, cramping or spotting pattern changes in a way that feels unusual for you. None of the material information in this guide is a substitute for a clinical evaluation, and self-diagnosing based on product materials alone is not a safe shortcut when symptoms are involved.
FAQ
Are organic tampons safer than regular ones? "Safer" isn't quite the right framing – both organic and conventional tampons sold through regulated retailers are manufactured under baseline safety and labeling requirements. Organic tampons are grown without most synthetic pesticides, which is the main documented difference; whether that translates into a measurable health benefit for the wearer hasn't been firmly established in large-scale research, so treat organic labeling as a farming and processing claim rather than a general safety upgrade.
Do scented pads cause infections? Fragrance in pads is more strongly linked to contact irritation and dermatitis than to infection directly, though irritated skin and disrupted local flora can make some people more prone to discomfort. If you notice itching, redness or unusual discharge after switching to a scented product, switching back to unscented is a reasonable first step, and persistent symptoms are worth a doctor's visit.
How long can I safely leave a tampon in? Follow the maximum wear time printed on your specific product's packaging, and never exceed it, even overnight. Using the lowest absorbency that manages your flow and changing regularly are the two most consistent pieces of guidance across brands for reducing toxic shock syndrome risk.
What's the difference between rayon and cotton tampons? Rayon is a manufactured fiber derived from wood pulp cellulose; cotton is a natural plant fiber. Both are used, often blended together, in mainstream tampons. Neither material has been shown to be categorically unsafe when manufactured to standard regulatory requirements, but some people prefer cotton-only products for personal or sensitivity reasons.
Is it normal for pads or tampons to cause dryness or discomfort? Mild dryness with a highly absorbent tampon on a lighter flow day is common and usually resolves by switching to a lower absorbency. Persistent discomfort, pain, or a sensation of dryness that doesn't improve with a product change is worth mentioning to a doctor rather than working through it alone.
Do period product materials affect fertility or hormones? Claims connecting period product materials to hormonal or fertility effects circulate widely online, but robust, peer-reviewed evidence establishing such a link in typical consumer use is limited. This is an area where it's worth relying on regulatory body summaries and peer-reviewed research rather than anecdotal claims, and raising any specific concern directly with a doctor.
