REACH, the European Union’s chemical safety regulation, is now becoming increasingly complex and expensive for coatings suppliers, both for those based in Europe and those exporting into the region.
The  strategy behind  REACH—an acronym for the Registration, Evaluation and Authorisation of  Chemicals—is that producers and importers register with safety dossiers all chemicals with a sale of above one ton a year and then the information in the dossiers will be passed downstream to formulators and end-users.

The legislation, first introduced in 2007 to be enacted over an 11-year period to 2018, is now at a stage where what is called exposure scenarios are being drawn up from the dossiers by both chemical suppliers and formulators to be distributed along the supply chain.  They detail what users need to do to control hazardous chemicals.

“Exposure scenarios are one of the main innovations of the REACH regulation,” said the European Chemicals Agency (ECHA), Helsinki, Finland, in a guidance document for downstream users issued in December.  The agency is responsible for administering the legislation.

Although the legislation has now been in operation for nearly seven years, there are still uncertainties about how to introduce and implement exposure scenarios.  They have turned out to be far more intricate than expected.
They describe how people and the environment may be exposed to a hazardous chemical or substance during its entire life cycle – from its use in the manufacture of a coating or other product, its application and disposal.   More importantly, the scenarios recommend how exposure to the substance should be controlled to ensure its safe use.

The big challenge for coatings companies and distributors is that their products can comprise more than 20 different chemicals each of which has its own REACH safety profile and exposure scenario.  Under the legislation the coatings producer or distributor has the responsibility of providing a exposure scenario covering  the chemicals in a single product.

For exporters of chemicals, coatings and other formulated products,  the exposure scenario requirement  reinforces a widely held view outside Europe that REACH is a barrier to trade. The Society of Chemical Manufacturers and Affiliates (SOCMA), representing U.S. speciality chemical producers, reckons that REACH compliance is equivalent to a tariff of more than 20 percent.

To help sort out the problems with exposure scenarios, ECHA has set up a task force of regulators and industry representatives – the Expert Network on Exposure Scenarios (ENES).  It is in the process of deciding how the risks of mixtures or formulations containing hazardous chemicals should be assessed.  It also investigating how the content of exposure scenarios, particularly the advice on how to manage risks, should be best communicated down the supply chain through extensions to a product’s Safety Data Sheet (SDS).

A major difficulty dealing with the risks from mixtures in coatings and other products is that toxicologists and other experts still cannot agree how to measure the dangers from chemicals in mixtures.
“We have been identifying (in ENES) at least 15 methods for evaluating mixtures but there are clearly others as well,” said Erwin Annys, REACH and chemicals policy director at the European Chemistry Industry Council (Cefic), representing chemical, including formulation, producers.

Another complication with exposure scenarios is the information on uses has to be passed upstream to the chemical and formulation producers for conversion into exposure scenarios.

Scenarios for individual chemicals are drawn up  by producers or importers both to be included in their REACH registration dossiers and to passed on to formulators. But those for mixtures are put together by coatings companies and distributors or other suppliers of formulated products mainly by relying on the information in the exposure scenarios provided by the suppliers of individual chemicals.
Critics of the exposure scenario concept claim that, due to the remoteness of chemical manufacturers and even formulators from end-users, information in scenarios on the risks of  individual chemicals is likely to be inconsistent with specific working conditions and processes.

The numbers of uses and processes covered in a typical exposure scenario could extend into double figures.  They include details of indoor and outdoor conditions, modes of application, types of packaging and delivery, mixing equipment, substance concentrations and task durations.  In addition the scenarios list recommended rick management or control measures, such as ventilation equipment and protection clothing and accessories.
To ensure that exposure scenarios are kept short and easy to understand, a system of generic exposure scenarios has been developed so that the scenarios can be drawn up by sector trade associations for distribution to the majority of their members.  This is a strategy which is being adopted by the European Council of Paints, Printing Inks and Artists Colours Industry (Cepe)—the main European coatings trade association.
“We believe that generic exposure scenarios will cover around 80 percent of normal uses of coatings and printing inks,” said Janice Robinson, Cepe’s director of product relations. “Providing exposure scenarios which apply to specific uses other than generic ones would be outside our responsibility.”

Within a consortium of formulator sectors—the Downstream Users of Chemicals Co-ordination Group (DUCC), which in addition to coatings companies embraces manufacturers of detergents, adhesives, crop protection products and construction chemicals – Cepe is working on the harmonization of information from chemical producers. This should help to prevent different exposure scenarios being provided for the same individual chemical.
“With the help of consistency in the information on substances, we can then ensure that the generic exposure scenarios match the risk data provided by the suppliers of hazardous chemicals,” said Robinson.
The big task facing DUCC and other individual or consortia organizations is the development of relatively uniform methods for assessing risks from chemical mixtures.  One key question is how inclusive the mixtures exposure scenarios should be.

“For mixtures there is no legal obligation to provide complete exposure scenarios of all substances but (this is) information which may be needed by some companies,” explained Ophelie Roblot, health, safety and environment director of the European Association of Chemical Distributors (FECC), at a recent ENES meeting.

Currently members of ENES are concentrating on developing an assessment system which would focus on gauging the impact of potentially the most hazardous substances within mixtures.
“Our intention is to find the overlaps between the different methods and to try to combine them in an approach which covers all the aspects of mixtures evaluation as much as possible so that it can be used virtually for every mixture,” said Annys.

The toxicology  of mixtures, however, is a relatively young science with issues like the reactivity of some hazardous chemicals within them still unclear.  Coatings formulators are likely to be still updating and refining the exposure scenarios of their products well beyond  2018 when the implementation of REACH is due to be completed.