What is a Persistent, Bio-Accumulative and Toxic (PBT) Assessment?

Within the EU, there is an obligation for anyone who places chemicals onto the commercial market to comply with R.E.A.C.H. This stands for Registration, Evaluation, Authorisation and Restriction of Chemicals and is designed to provide a high level of protection for human health and the environment from the use of chemicals.

ECHA guidelines for manufactures

The European Chemicals Agency (ECHA), based in Helsinki, have issued guidelines which help manufacturers (or ‘registrants’ as they call them) negotiate and comply with the assessment process for R.E.A.C.H.  This assessment process is extremely rigorous and falls under the acronym PBT, which stands for Persistent, Bio-accumulative and Toxic and can be done at any registered testing facility. ECHA outlines the testing process at the following link: ECHA

PBT Assessment and Environmental Concerns

Essentially, toxic substances that persist for long periods of time in the environment have a high potential to accumulate in biota (plant and animal life of a particular region) and are of particular concern because their long-term effects are rarely predictable. Once they have entered the environment, exposure to such harmful substances is often very difficult to reverse. Forest/woodland sites are particularly vulnerable, so focusing attention on the PBT assessment is so important.

Following Brexit, EU R.E.A.C.H.  regulations were incorporated into UK law in 2021 and are known as UK R.E.A.C.H.  They cover materials manufactured in the UK and imported, including diverse items from car parts to clothes. They also apply to biodegradable tree shelters.

PBT and biodegradable tree shelters

So far, the UK manufacturers of biodegradable tree shelters have yet to talk much about PBT. ISO 17556 soil biodegradability has been the focus of much attention, along with standards such as TUV OK biodegradable SOIL (essentially the same thing). However, standards such as ISO 17556 were designed to cover the inappropriate disposal of packaging waste or the safe incorporation of short-life mulches into soil. They were not intended to cover products such as tree shelters, which must fulfil a protective function in an unpredictable, natural environment for several years before degrading into that same environment without any detrimental effects. There is currently no standard for such a long-term and variable process, which is why PBT assessment is so important.

NexGen and PBT compliance

When it comes to NexGen, the constituent elements have either already passed PBT assessment or are classed as naturally occurring low-hazard substances, which are exempt. This is why we can be confident that NexGen material is neither persistent, bio-accumulative, or toxic, giving customers the ultimate protection and knowledge that what they’re putting onto forest or landscape sites will not harm the environment in any way.

Of course, proving that your product passes the PBT assessment is no guarantee that it will function effectively as a tree shelter; that it will blend sympathetically into the natural surroundings; that it will ameliorate the detrimental effects of ever hotter summers; or that the manufacturing process will provide much needed revenue for hard-pressed sheep farmers. Only NexGen can tick all of those boxes.



NexGen. Protect your young trees. Protect the environment.

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