Slash Period Product Carbon Footprint in 6 PFAS Safe Washing Steps
Menstrual cups carry the lowest carbon footprint of any period product, with period underwear and reusable pads close behind, all landing well below single-use tampons and pads over a year of use. The gap comes down to a handful of kilograms of CO2e annually for reusables against far higher totals for disposables, though washing habits and a recent PFAS concern in some reusable items complicate the picture. The practical path to a lower-impact period involves choosing a reusable option and pairing it with smarter laundry habits.
TL;DR:
- Menstrual cups have the lowest carbon footprint, with estimates around 0.066 kg CO2e per user annually, due to their durability and minimal washing needs.
- Reusable period underwear and cloth pads rank second and third, with their environmental impact mainly from manufacturing and laundering, but they break even quickly with efficient washing.
- Washing habits significantly affect the footprint of reusables, with cold water, full loads, and line-drying reducing emissions substantially.
- About one-third of tested period underwear and a quarter of reusable pads contain PFAS compounds, prompting the need for brand transparency and cautious washing practices.
- Switching to reusables offers meaningful climate benefits, but choosing products from brands that disclose life-cycle data and minimizing wash frequency further enhances sustainability.
Table of Contents
- How life-cycle assessments measure a period product’s carbon footprint
- Comparing the carbon footprint of cups, underwear, pads, and tampons
- How your laundry routine changes the footprint of reusables
- What PFAS testing found in reusable period products, and what to do about it
- A simple checklist to lower your period’s carbon footprint
- Why we see reusable underwear as the practical lower-carbon choice
- Start your switch to lower-carbon period underwear
- FAQ
- Sources
How life-cycle assessments measure a period product’s carbon footprint
A life-cycle assessment, or LCA, tracks the environmental cost of a product from raw material extraction through manufacturing, transport, use, and disposal. It is the right tool for comparing cups, pads, tampons, and underwear because it captures impacts that a sticker price never shows, like the energy spent growing cotton or running a washing machine.
For single-use products like tampons and pads, raw material sourcing and manufacturing dominate the footprint since each item is made once and thrown away. For reusables like cups and period underwear, the use phase, mainly washing, becomes a bigger share of lifetime emissions because the product is cleaned repeatedly over months or years.
Figures vary between studies for a few consistent reasons: some LCAs assume a longer or shorter product lifespan, some use regional electricity grids that are cleaner or dirtier, and some assume more frequent or more efficient washing than real users practice. That is why a UNEP LCA meta-study pooling multiple assessments gives a more reliable picture than any single paper.
Comparing the carbon footprint of cups, underwear, pads, and tampons
Menstrual cups sit at the bottom of the emissions scale, with some LCA estimates putting them around 0.066 kg CO2e per user per year, according to the UNEP meta-study. Their footprint stays small because one cup can last several years and requires only brief sterilizing between cycles, not a full wash cycle.
Period underwear typically ranks second, reflecting the choice of organic and recycled materials that support sustainable comfort. Its footprint comes mostly from manufacturing (the fabric layers and construction) plus the energy used in repeated laundering, but since the garment doubles as underwear and absorbent layer in one piece, it carries a lighter manufacturing burden than owning separate underwear and a reusable pad, a point raised in cross-country LCA comparisons. Reusable cloth pads rank third, with a similar mix of manufacturing and laundering emissions but typically less fabric efficiency per use than underwear.
Tampons and disposable pads sit at the top of the scale. Their impact is driven almost entirely by raw material and manufacturing, since every single item used over a lifetime has to be produced and shipped once each. A 2024 peer-reviewed review estimates that disposable menstrual products, roughly 12 billion units used globally each year, contribute about 245,000 tonnes of CO2 annually worldwide.
Break-even math favors reusables quickly. A BBC Future explainer notes that menstrual cups often offset their own production emissions within about a month of typical use, while period underwear and reusable pads break even faster when owners wash efficiently and keep the product in rotation for its full lifespan.
How your laundry routine changes the footprint of reusables
Washing is where reusable products can lose their environmental edge if done carelessly. Hot water washes, partial loads, and tumble drying all push up the electricity and gas used per cycle, and UNEP guidance on washing practices identifies laundering choices as the single biggest source of variation in reusable product footprints.
A few habits make a real difference:
- Wash in cold water whenever your underwear or pads are not heavily stained.
- Run full loads instead of washing a few pieces at a time.
- Choose an energy-efficient machine where you have one available.
- Line-dry instead of tumble-drying to cut electricity use substantially.
- Sterilize a menstrual cup with a kettle, small covered pot, or microwave method per the manufacturer’s instructions rather than boiling large volumes of water.
Pro Tip: Pair a menstrual cup with a backup pair of period underwear on your heaviest flow days so you wash less often overall, without adding a disposable product to the mix.
A reader doing cold, full-load washes with line-drying will cut the use-phase emissions of their underwear or pads dramatically compared to someone running small hot loads through a dryer every time.
What PFAS testing found in reusable period products, and what to do about it
A 2025 screening covered in reporting on PFAS in period products found that about one-third of tested period underwear and one-quarter of tested reusable pads contained fluorine at levels suggesting PFAS, with some samples showing fluorine concentrations above 1,000 parts per million. That is a meaningful share, and it raises a legitimate question for anyone switching to reusables for health as well as environmental reasons.
The likely exposure routes are skin contact during wear and PFAS entering wastewater during washing. Public-health guidance from NASPAG calls for more brand transparency and further research, while noting that food and water remain the largest sources of PFAS exposure for most people.
Until testing becomes standard across the category, look for brands that publish lab results for fluorine or PFAS, favor products marketed as PFAS-free with evidence to back it up, and follow the washing guidance above, since reducing wash frequency and using cooler water may also limit how much leaches out over a product’s life. The climate benefit of switching from disposables remains real even as this chemical question gets sorted out.
A simple checklist to lower your period’s carbon footprint
- Start with a menstrual cup for your lowest-impact option, or pair one with period underwear for backup on heavy days.
- Wash cold and in full loads rather than running small, hot cycles after every use.
- Line-dry instead of tumble-drying whenever your schedule allows it.
- Repair small issues like loose seams instead of replacing a product early.
- Choose brands that publish LCA data or PFAS lab results so your purchase decision has real numbers behind it.
- Advocate for washing infrastructure at school, work, or shared housing if lack of laundry access is what is pushing you toward disposables.
Why we see reusable underwear as the practical lower-carbon choice
We think period underwear earns its place as a realistic lower-carbon choice for most people, even with the laundering caveat and the PFAS questions raised by recent testing. The data favor cups first, but underwear fits daily life more easily for many, and a garment that lasts years beats one used once.
Our own stance: test one piece, learn your wash routine, and decide from there rather than committing to a full wardrobe swap immediately.
— Tiera
Start your switch to lower-carbon period underwear
We built our Period Underwear collection around the idea that one reusable piece should outlast a box of disposables, with options for heavy, moderate, and light flow days plus dedicated lines for teens and postpartum recovery.
If you want the laundering details that keep a lower footprint intact, our guide on how to wash period underwear and make it last walks through cold-wash and drying steps, and our care guide covers stain removal without harsh treatments. We also publish our own testing transparently in our PFAS lab results so you can check materials before you buy.
- Browse Heavy Flow Protection for high-absorbency days.
- Try Moderate Flow Days for everyday wear.
- Check For Teens or Postpartum Care for those specific needs.
FAQ
What are the most environmentally friendly menstrual products?
Menstrual cups carry the lowest carbon footprint among period products, with LCA estimates putting them around 0.066 kg CO2e per user per year. Period underwear and reusable cloth pads follow close behind, both well below single-use tampons and pads.
Why don’t they use tampons in Japan?
This is a cultural and market preference rather than an environmental policy, and pad use has historically been more common than tampon use in some countries for reasons tied to habit and product availability rather than any carbon-footprint comparison. The sustainability differences between product types come down to life-cycle factors like manufacturing and laundering, not geography.
Do period cups leach microplastics?
Current public research on period products has focused more on PFAS in some reusable pads and underwear than on microplastic leaching from cups specifically. Medical-grade silicone cups are generally considered a low-risk material, though ongoing chemical-safety research continues to call for broader testing across reusable product categories.
Are tampons or pads more environmentally friendly?
Neither single-use option has a clear environmental edge over the other since both are driven by raw material sourcing and one-time manufacturing, according to the 2024 peer-reviewed review on menstrual product impacts. Reusable alternatives like cups, underwear, and cloth pads outperform both on a per-year carbon basis.
Sources
- Environmental impact of menstrual hygiene products (PMC)
- UNEP LCA meta-study on menstrual products
- Pads, pants or cups: Which period product is the most climate-friendly? (BBC Future)
- Research update: PFAS found in several reusable period products (EurekAlert!)
