Chemicals have understandably been the subject of increasing regulation in recent years, with high levels of focus brought on to subjects of emission levels, toxicity and hazards to health and the environment.
The raw materials used in the chemical compositions used for wood products adhesives have also been hit by high inflation and the Ukraine conflict, leading to large increases in costs for wood-based panels producers.
At the European Wood-based Panels Symposium (see pp24-28) Professor Rainer Marutzky, managing director of the Association for Technical Wood Issues (iVTH) tackled the national and European requirements for VOC emissions from construction products – focusing on the current situation for wood-based panels.
Prof Marutzky had some warnings for delegates in the wood-based panel industry to be vigilant of regulators finding new ways of implementing restrictions.
He started his presentation with a quote from former British prime minister Winston Churchill: “If you make ten thousand regulations you destroy all respect for the law.”
Setting the scene, Prof Marutzky shared how since about 1980, analytical test methods and evaluation procedures were developed for the measurement of VOC emissions in Europe. Since 1995, voluntary and legal VOC testing and evaluation systems were introduced in some European states.
Legal VOC evaluation schemes exist in Belgium, France and Germany. The Belgian and German schemes are based on the EAC scheme. They both include VOC, SVOC and some VVOCs. They are both pass and fail schemes.
The French system is based on EN ISO 16000. It includes the TVOC value and 10 selected VVOCs and VOCs. It is an informative system with four emission classes (A*, A, B and C). You cannot sell your product if you exceed those values.
GERMAN AGBB SCHEME
The AgBB scheme in Germany has five parameters, two of which are important for wood products – TVOC and R-value (risk). Since 2019, the AgBB scheme has included two wood products, OSB and particleboard, basically limiting emissions of these boards used in the German market under federal building regulations.
Two large European panels manufacturers filed lawsuits against the German regulations, with two legal procedures brought before administrative courts in Baden-Württemberg and Bavaria.
Both courts declared the VOC regulations for the two panel types “invalid” from a hazard prevention perspective. An appeal of the judgements was not allowed. But despite this clear decision, Prof Marutzky said there were no changes made to the regulations.
“But VOC regulations in particleboard and OSB on the basis of the AgBB scheme should be missing in the future,” he added.
“I believe that towards the end of the year [2022], the problem building regulations will no longer contain it.”
He said VOC regulations for OSB and particleboard according to another scheme should require new building regulations.
Prof Marutzky warned the panels industry that regulators may focus on other areas. “But we hope it will not focus on particleboard and OSB.”
He said regulators would risk “strong arguments” if they attempted to reintroduce similar regulations. He advised that regulatory activities should be “tracked” at national and European level, with contact and co-operation made with responsible committees and related associations.
“Be cautious and observe them with open ears and open eyes,” he said.
Prof Marutzky also advised that the climate protection advantages of woodbased panels should be promoted, as well as the results of health-related projects and existing findings.
MELAMINE UNDER THE SPOTLIGHT
Dr Manfred Dunky, of XYLO Technologies Ag, outlined some of the challenges facing wood-based panel producers over recent years, including high costs for raw materials, chemicals, energy and transport, with availability issues for raw material.
He listed the environmental challenges and burdens, including ongoing restrictions for various chemicals – formaldehyde, melamine, PMDI (isocynatates) and VOCs.
The development of bio-refineries has also created additional pressure on raw materials, as they sometimes use wood, food waste and crop residues.
One new bio-refinery in Leuna, Germany, developed by UPM, has a 220,000t annual capacity, producing glycols, lignin based fillers and industrial sugars.
Dr Dunky also identified the increasing trend of burning wood as adding pressure on the wood raw material availability stream.
Moving to wood adhesives specifically, he estimated total demand of wood adhesives in Europe to be six million tonnes/year. He listed the main changes in the last decades for aminoplastic adhesive resins for PB and MDF/HDF were higher reactivity, better crosslinking and stringent quality control of raw materials and their influence on the chemical reactions, in order to keep resin quality consistent.
Formaldehyde emissions have also been reduced, and there is the addition of a catcher (eg urea) in different form and at different stages of the production process. Mr Dunky highlighted a potential threat to widely-used melamine.
The German Federal Institute for Occupational Safety & Health (BAuA) published a summary of its Risk Management Option (RMOA) analysis on melamine.
This includes melamine meeting the criteria to be identified as a substance of very high concern (SVHC) having probable serious effects to the environment.
The RMOA proposes to address the reproductive toxicity of melamine through a harmonised classification for Reprotoxicity 2 with Hazard Statement H361f (suspected of affecting fertility) under the Classification, Labelling and Packaging Regulation.
An indicative occupational exposure limit value for the workplace as human exposure limits to hazardous substances shall be established.
BAuA submitted its case to the European Chemicals Agency (ECHA) on August 4, 2022. ECHA started 45 days of public consultation on September 2 (lasting until October 17), when stakeholders could challenge the basis for SVHC identification of melamine.
Based on the results of this public consultation, ECHA will decide on the further procedure: most likely evaluation in the ECHA Member State Committee followed by a decision by the EU Commission. But why precisely is melamine under observation?
Dr Dunky reminded delegates about the 2008 infant milk scandal in China, when melamine in the milk product led to severe health problems for thousands of infants. BAuA estimated that melamine fulfils the PMT criteria – Persistent, Mobile and Toxic.
Traces of melamine are found in surface and ground water in Germany and The Netherlands, as well as microplastic levels in the River Rhine but there is no clear picture.
Mr Dunky said there was no clear evidence of melamine leaking from waste wood-based panels (eg landfilling), with the content of melamine in panel consumer products such as kitchen worktops of MF-laminated particleboards far below any actual and future limit.
So, consequences for the wood-based panels industry in the case of SVHC classification of melamine are: discussion with customers and end-users; the risk of downgrading/excluding panels in building rating schemes; negative consumer perspective so substitution to less sustainable materials; and no real substitutes available. Natural adhesive replacements are starting to be used, but currently only in niche products.
Mr Dunky outlined five concepts of biobased adhesives in the future:
- Original idea of fully naturally-based adhesives, eg “lignin-adhesive”
- Partial replacement of synthetic raw materials by naturally-based chemicals, eg phenol partly replaced by methylolated lignin
- New: Use of green chemicals (as new monomers) from bio-refineries, then following established synthesis ways: either (i) purified and well-defined chemicals or (ii) “in situ” mixtures as just achieved in various steps of the bio-refinery process, such as 5-hydroxymethylfurfural (5-HMF) (+)
- New: Well-established formaldehyde based resins, but using “green hydrogen” instead of natural gas to produce methanol and urea
- New: bio-gas (mainly methane) instead of fossil natural gas to produce methanol and urea
Dr Dunky said there were several obstacles for these new concepts, including costs and prices, with the comparison depending on the price of natural gas.
Availability was also a question, as millions of tons were needed just for wood adhesives, alongside many other possible applications.
Lastly, is the question of the quality of the various intermediate products – is bio-methanol suitable for formaldehyde production due to possible impurities?
