Chlorine free products, by themselves, are not guaranteed to be free of old growth fibers. However the bleaching process used to whiten products, particularly paper, paper products, and tissue products, is another critical environmental factor to consider when measuring the environmental credibility of a given product.

Chlorine used in manufacturing processes is damaging to the environment and to human health. As early as 1985, the U.S. Environmental Protection Agency (EPA) labeled dioxin "the most potent carcinogen ever tested in laboratory animals."

Chlorine bonds chemically with carbon-based compounds (such as lignin in trees, the cellular material that creates the tree's structure) to produce dioxins and toxic pollutants. When released into water, they do not break down. Dioxins, even when released in miniscule amounts, bio-accumulates as it moves up the food chain, reaching its highest concentration in humans, where it is increasingly linked to cancers as well as endocrine, reproductive, nervous and immune system damage.

There are four bleaching terms that are important to understand. Two describe processes to avoid, and two describe processes to encourage.

Action Acronym Bleaching Process Description
Avoid   Elemental Chlorine A gas that brightens paper fibers and removes lignins. It binds with carbon-based compounds (such as trees) to produce dioxins and toxic pollutants.
Use only if better alternatives are not available ECF Elemental Chlorine Free Uses one of several chlorine compounds, most often chlorine dioxide but also sodium hypochlorite and others, that significantly reduce dioxins but do not eliminate them. Paper companies using ECF often say that dioxin is 'nondetectable' in their wastewater. This refers only to the sensitivity of prescribed tests, and does not necessarily mean there are no dioxins. State-of-the-art tests are often able to detect dioxins when prescribed tests find them nondetectable.
Prefer TCF Totally Chlorine Free Uses only non-chlorine bleaching processes, including oxygen and ozone bleaching systems. Eliminates dioxins and chlorinated toxic pollutants by not producing them in the first place.
The Best PCF Processsed Chlorine Free Uses totally chlorine free processing and includes recycled content. Both the recycled fiber and any virgin fiber must be bleached without chlorine or chlorine compounds.

Source: Susan Kinsella & Associates