What happens to the chemicals afterwards
Short answer: Some of the chemicals are recovered and reused, some are broken down in the treatment plant, and a small remainder can stay in the fabric until it is washed out in rinsing. Here is what happens in practice, and why a new garment should be washed before use.
Recovery where it pays
Some chemicals are expensive enough that collecting and reusing them pays off. That applies, for example, to the solvent in the lyocell process, which is kept in a closed loop. Other substances are so cheap or so hard to collect that they are rarely recovered, and go to treatment instead.
Breakdown in the plant
Organic substances are broken down by bacteria in a biological treatment stage. It is the same principle as in a municipal treatment plant, where bacteria consume what can be broken down. Some substances do not withstand it and need another treatment, for example with carbon or chemical oxidation. See bamboo dresses.
The rest is rinsed out of the fabric
After each chemical process the fabric is rinsed thoroughly, and the rinse water goes to treatment. Even so, a small remainder can stay in the fibres, and that remainder may follow into the finished item. So the last rinses are an important part of the process, and they are often checked separately.
Why new clothes are washed
A new garment should be washed before use. The wash removes residues from production and transport, such as dust, and softens the fabric so it feels better against the skin. It is a simple habit worth having, and it applies not only to viscose but to clothing in general.
Can there be residues in a garment
There may be traces. Certifications set limits for what may remain, and there are tests that measure the content of selected substances in finished clothing. That does not mean clothing is entirely free of traces, but that amounts are kept under set limits. See women's bamboo pants and JBS.
Who checks it
Checking happens in two ways. Testing institutes examine samples in connection with certification, and authorities take spot checks of goods on the market. Neither can check everything, so the system relies on producers documenting their own production and keeping track of their suppliers.
Why a label is not enough
A label says something about the requirements it stands for, but it does not cover everything. A certificate can, for example, apply to one stage of production or to one item. So read what a label covers, and check whether it applies to the garment you are considering buying.
What you can do
Wash new clothes before first use, use a mild detergent and rinse well. If you have very sensitive skin, an extra rinse can be a good idea. If you have questions about how your skin reacts to clothing, talk to your doctor, since the content of the clothing alone cannot decide it.
At the checkout
If you ask what is in a particular garment, start with the content label, which says which fibres it is made of. It does not tell everything about production, but it is the most reliable place to begin. If you are unsure, it is usually better to ask than to guess.
Frequently asked questions
Can there be residues in a finished garment?
There may be traces. Certifications set limits for what may remain, and there are tests that measure the content of selected substances in finished clothing.
Why is washing before use recommended?
To remove residues from production and transport and to soften the fabric. It is a simple habit that applies to all new clothing, not only viscose.
Who checks it?
Testing institutes in connection with certification and authorities through spot checks. Neither can check everything, so producers also have to document their own production.
You can find the full range at Bamboo-Clothing.com.
