Newspaper Composting: Which Inks Are Safe Today

For decades, the gardening advice was clear: don’t compost newspaper. The inks contained lead and other heavy metals that would contaminate the finished compost. Generations of gardeners learned to avoid newsprint in the pile.

That advice is now significantly out of date. Newsprint inks have changed substantially since the 1990s. Today, the vast majority of US daily newspapers use soy-based or vegetable-based inks that are safe to compost. The lead-pigment warning is a historical artifact, not current concern.

But the situation is more nuanced than just “compost away.” Glossy inserts use different inks. Tabloid free papers sometimes use the cheaper formulations. Color newspaper sections are more complex than black-and-white. Let’s walk through what’s actually safe today.

What modern newspaper inks are made of

US daily newspapers — the New York Times, Washington Post, Boston Globe, USA Today, Los Angeles Times, regional metros, and the long tail of mid-size dailies — almost uniformly use soy-based black inks for their main news sections. The American Soybean Association’s industry tracking showed that by 2010, over 90% of US daily newspapers had switched to soy-based black inks; that figure is now over 95%.

The soy-based ink composition is:

Pigment: Carbon black (essentially ultra-fine soot) as the main coloring agent. This is the same carbon black used for centuries; it’s not chemically problematic. Carbon black makes up roughly 15-20% of the ink by weight.

Vehicle (the liquid that carries pigment): Soybean oil derivatives, mostly soybean oil esters with small amounts of resins. About 70-80% of the ink. Soy oil replaces the petroleum-based mineral oils that were standard before 1995.

Drier and additives: Small amounts of metallic soaps (typically calcium and zinc) and surfactants to control drying and viscosity. These are present at less than 5% of total ink weight and are food-contact-safe at those concentrations.

Color newsprint inks — the inks used for color photos and ads in the daily news section — also moved to soy or vegetable oil bases starting around 2005-2010. Most US daily newspaper color sections today use soy-based four-color process inks (cyan, magenta, yellow, black). The pigments in CMY inks are organic dyes (azo, phthalocyanine families) that are non-toxic at the concentrations present.

What’s gone from modern newsprint: lead-based pigments (essentially eliminated in US printing by 1985 under federal regulation), petroleum mineral oils (largely phased out by 2000-2010), and most concerning heavy metals (vacated by industry voluntary standards by the early 2000s).

What’s still in glossy inserts and magazines

The picture changes when you look at glossy inserts — the colorful coupon booklets, real estate listings, and ad supplements that fall out of Sunday newspapers. These are printed on coated paper using different inks than the main news section.

Glossy insert inks:

More likely to be petroleum-based. Coated paper requires different ink chemistry than uncoated newsprint. Many glossy inserts still use petroleum-derived ink vehicles because the printing process at high speeds with coated paper benefits from the petroleum’s flow characteristics.

May contain UV-cured polymers. High-end glossy printing uses UV-curable inks that polymerize under UV light during printing. The cured polymer is essentially inert plastic — it won’t biodegrade in compost the way ink should.

Often have heavier metal content. Bright “metallic” colors in glossy inserts may use aluminum or bronze powder pigments. While these are usually food-safe in finished products, the concentrations in inserts are higher than in regular news.

Coating on the paper itself. Glossy paper is coated with kaolin clay, calcium carbonate, or polymer coatings to create the smooth printable surface. These coatings can be either compostable (clay and calcium carbonate are fine) or not (polymer coatings persist).

The composting recommendation for glossy inserts is: avoid. Not because they’re acutely dangerous, but because the chemistry is variable, the coatings may not break down, and you have no way to know what’s in any specific glossy insert.

Real-world composting recommendations

Based on the chemistry above, here’s a practical guide:

Compost without concern:
– Main news section, black and white text pages (US daily newspapers)
– Color news section pages with color photos and graphics
– Sports section, op-ed pages, classified ad pages
– Local newspaper editorial pages

Compost with mild caution (chop or shred to speed breakdown, mix with other browns):
– Magazine pages that are matte-finish (not glossy), printed on uncoated paper
– Some weekly tabloid free newspapers (depends on the publisher; check if you’re uncertain)
– Black-and-white pages from glossy publications (the ink is still primarily soy-based, but the paper coating may not break down well)

Don’t compost:
– Glossy magazine pages with full color (covers, photo spreads)
– Glossy newspaper inserts (coupon booklets, real estate listings)
– Catalogs printed on coated paper
– Junk mail with metallic colors or shiny coatings
– Receipts printed on thermal paper (BPA concerns separate from ink)
– Pages with extensive metallic colors (gold, silver, copper) — these use metal-powder pigments

How to actually use newsprint in a compost pile

Newsprint is a useful brown (carbon-rich material) for compost piles. It serves three functions:

Bulking agent. Shredded newsprint fluffs up wet kitchen scraps and prevents the anaerobic mat that forms when wet greens compact. A 4-inch layer of shredded newsprint between layers of kitchen scraps keeps a pile breathable.

Moisture moderation. Newsprint absorbs excess moisture from over-wet piles. If your compost is too wet (sour smell, anaerobic feel), adding shredded newsprint will pull moisture out and restore aerobic balance.

Weed barrier. Sheets of newsprint laid as a weed barrier under mulch composts in place over a single growing season, suppressing weeds while breaking down.

To prepare newsprint for composting:

1. Sort out glossy inserts. Toss those in regular recycling.
2. Shred or tear the news section. Strip shredders work; so do scissors, so does just tearing into 1-2 inch strips by hand.
3. Add to the pile in moderate volumes — newsprint shouldn’t be more than 20-25% of the brown layer. Mix with other browns (dead leaves, cardboard, straw) for variety.
4. Water lightly. Newsprint is very absorbent and pulls moisture from the surrounding pile if added dry; pre-wetting prevents this.

For compost liner bags used in household collection bins, BPI-certified bags break down at similar rates to newsprint and can be added to compost piles whole without removing the bag.

How long newsprint takes to decompose

In a hot pile (130-150°F), shredded newsprint breaks down in 4-8 weeks. In a cold pile, 4-8 months. In a worm bin, 2-4 months (worms eat newsprint readily, especially when wet).

Whole sheets of newsprint break down much slower — sometimes 12-18 months. The slower breakdown is because the paper fibers are still in sheet form; shredding exposes more surface area and accelerates microbial attack.

If you find unbroken-down newsprint in finished compost, it’s not a problem. Just toss it back into the next pile. The lignin and cellulose in newsprint are entirely compostable; they just take longer than kitchen scraps.

What about color photos?

A common worry: “the color photos in newspapers have lots of ink — is that a problem?”

Color photos in daily newspapers use four-color process (CMYK) inks. Even at full ink coverage (a saturated full-color photo), the ink weight is about 0.5 grams per page maximum. In a typical newspaper, the average ink coverage including all photos and text is around 0.2 grams per page. The remaining mass of a typical newspaper page (about 5-7 grams) is paper fiber.

So even if every ink in a newspaper were toxic, the contamination potential is small relative to the paper bulk. With modern soy-based inks, the contamination potential is essentially zero. Color photos don’t pose a meaningful different concern than text pages.

What changed in the ink industry

The transition to soy-based inks happened because of three things:

Iowa farm-state political advocacy. The American Soybean Association lobbied for soy inks starting in the 1980s, both as an environmental story and as a domestic crop demand booster.

Petroleum price volatility. Newspaper economics are tight; ink costs matter. When petroleum prices spiked in the late 1990s and again in 2008, soy-based ink looked relatively more attractive.

Environmental regulation. The US EPA‘s pollution prevention initiatives encouraged ink manufacturers to reduce volatile organic compound (VOC) emissions. Soy-based vehicles emit much lower VOCs than petroleum vehicles, and the regulatory pressure accelerated the transition.

By the mid-2000s, soy-based inks were the standard for black newsprint. By 2015, soy was dominant for color newsprint too. The transition is essentially complete for daily news; it’s incomplete for high-end glossy printing where soy-based inks don’t yet match the optical and durability properties of petroleum-based inks.

A few specific edge cases

Comic strips printed in color: These are typically printed in the daily news section using the same four-color process inks as photos. Safe to compost.

Sports scores pages: Same printing process as the rest of the news section. Safe.

Sunday inserts that look matte rather than glossy: Sometimes these are printed on standard newsprint paper rather than coated paper. If the paper feels like regular newsprint (not slick or shiny), it’s almost certainly safe to compost.

Magazines from libraries or doctor offices: Usually glossy. Recycle rather than compost.

Children’s coloring books or activity pages: Usually matte newsprint, soy inks. Safe to compost.

Crossword puzzle books: Newsprint paper, soy ink. Safe.

Pages with your handwriting in pen or pencil: Pen ink (Bic, Pilot, etc.) and pencil graphite are present in tiny amounts and don’t change composting suitability.

What this means in practice

If you’ve been avoiding all newspaper composting because of old advice about lead inks, you can change that habit. Modern US daily newspapers are safe to compost in any home or municipal compost system. The black-and-white news section, the color photos, and the editorial pages all use soy-based inks at this point.

What to keep avoiding: glossy inserts, magazine covers, catalog pages, and anything that has a slick coated paper feel. These haven’t transitioned to soy inks and the paper coatings are unpredictable.

For most households, this means shredded newspaper is now a legitimate brown to add to the compost pile. It’s free, it’s absorbent, it’s available in large volumes after a Sunday paper, and it composts in 6-8 weeks under good conditions. The old gardening advice can be retired; the chemistry has moved on.

For B2B sourcing, see our compostable supplies catalog or compostable bags catalog.

Verifying claims at the SKU level: ask suppliers for a current Biodegradable Products Institute (BPI) certificate or an OK Compost mark from TÜV Austria, and check that retail-facing copy meets the FTC Green Guides qualifier requirement on environmental claims.