Healthier adhesives: Always adhere to best practice


Healthier adhesives:
Always adhere to best practice 

Users of chemical fasteners, sealants and fillers often overlook the hazards of toxic compounds, but it is possible to identify safe alternatives, writes JOHN POWER.


Adhesives and similar products in the sealant-filler family are often taken for granted by both professional and DIY users; after all, application is often swift – just one aspect of a larger and more complex set of tasks – and there is a twin assumption that dangers cease to exist once products have cured. Besides, there must be some agency that blocks dangerous products from entering the market in the first place, right? Wrong.

The reality is that adhesives and related products can pose significant health hazards both during and after application, despite the best intentions of authorities like the Australian Building Codes Board (ABCB) to uphold rigorous safety standards. Imported products, in particular, are not always easy to scrutinise or check at a chemical level. And there is an extra layer of complexity: we’re not just talking about tubes or tubs of branded adhesives and similar families of products; toxic adhesives may be present ‘within’ a huge array of building products where the offending compounds have been used in the actual fabrication process of the material. For instance, plasterboard, MDF and laminate timber products are good examples of products that might contain dangerous levels of toxic chemicals, potentially releasable into the atmosphere by users when cutting or sanding, or if the material is exposed to moist conditions. In other words, dangers from adhesives exist even if a builder is only using mechanical fasteners (nails, screws, etc) on a particular project.
Trying to keep on top of the potential sources of chemical hazards from adhesives (or related solvents or hardening agents) in building materials and liquid fasteners is a nightmare, made all the more difficult in a marketplace full of non-compliant or poorly labeled product. Oftentimes, a user only becomes aware of a problem when noticing foul odours, or suffering from sore eyes, itchy skin, or some other physical irritation – a clearly unsatisfactory quality control process.

A worthwhile aid, thankfully, is the newly released Good Environmental Choice Australia (GECA) Adhesives, Fillers and Sealants Standard (AFSv4.0-2014). Though a new version of an existing Standard, this Standard is in effect a new document, comprising an array of additional safety and performance criteria and benchmarks.

List of dangers
The document highlights the myriad health risks associated with this category: “Adhesives, fillers and sealants can contain a large range of chemicals that ensure superior binding strength for a large range of applications. The chemical components of adhesives, fillers and sealants can include binders, solvents/thinners, plasticisers, fillers/bulking agents, thickeners, anti-foaming agents, preservatives and a large range of other chemical additives whose respective functions add to the products intended purpose.”
As a means of combating such problems, the Standard requires adherents to address overt dangers by ensuring, among other things, that certain substances (listed as Hazardous by Safe Works Australia) must not be used in a given product. Furthermore, products “must not be classifiable as dangerous according to the Australian Dangerous Goods (ADG) code, including classification as an Environmentally Hazardous Substance”.
Crucially, the Standard expressly forbids the intentional use of Isocyanates; Bisphenol A; Toluene and Toluene compounds; APEO – Alkylphenolethoxilates and other Alkylphenol derivatives; persistent, bioaccumulating and toxic organic compounds (PBTs); or Substances of Very High Concern (REACH Candidate List).
Formaldehyde, one of the most toxic substances often associated with non-compliant adhesives, is also forbidden from intentional use according to the terms of AFSv4.0-2014 [with the exception of newly produced polymers, when a small concentration of no more than 250 ppm (0.025 weight %, 250 mg/kg) is permitted, provided that the content of free formaldehyde in the toughened product does not exceed 10 ppm (0.001 weight %, 10 mg/kg)].
Heavy metals and Volatile Organic Compounds (VOCs) are also singled out for special mention in the Standard. Toxic heavy metals and its compounds, or ingredients containing heavy metals and their compounds, including lead (Pb), cadmium (Cd), mercury (Hg), chromium (Cr), arsenic (As), selenium (Se), cobalt (Co), tin (Sn) and antimony (Sb), must not be deliberately added or used.
Similarly, VOCs must be limited to small stipulated concentrations (65–250 g/L, depending on the class of product).
A range of additional clauses exists to ensure best practice in relation to reduced energy wastage during manufacturing processes; protection from biocides; and the absence of Crystalline Silica (Quartz) or Mica (or the use of effective controls to prevent breathable hazards).

First accredited company
The first accredited adherent to AFSv4.0-2014 is Australian plasterboard manufacturer CSR Gyprock, which recently gained accreditation for the bulk of its range of adhesives, fillers and sealants. By holding this voluntary accreditation, Gyprock can reinforce claims that its products have been independently assessed to meet environmental, human health and ethical impact criteria.
In a recent announcement to the industry, CSR Gyprock stated that by satisfying the new Standard across the majority of its compound range, “customers can now expand on their environmental choice, enabling contractors, builders and designers to confidently comply with global best practice in product certification and eco-labelling for the Australian market.”
In a nutshell, products that comply with the AFSv4.0-2014 Standard feature minimised VOC content; no known carcinogens, mutagens or reproductive toxins; and measures in place to prevent the inhalation of crystalline silica and mica.

Codes & standards matter
While authorities such as the ABCB play a vital role in setting and formulating safety thresholds for products and building systems used in Australia, enforcement is another issue.
The building industry is ripe with inordinate quantities of imported building materials and products. Given the sheer volumes of materials, even mandatory Standards have little force in ensuring that all products are correctly labelled, or that claimed properties and characteristics are truthful.
In reality, the only way to distinguish between compliant safe adhesive products and non-compliant products is to rely on quality assurance schemes like GECA, which act as independent umpires and champions of high-quality items. The next best quality control system is to rely on the integrity of reputable brands.
Retailers offering adhesives (or materials fabricated using adhesives) to the marketplace should have a good working of knowledge of Standards such as AFSv4.0-2014, which are often the only barometers a customer has to inform safe purchasing decisions.

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