Environmental Engineering Reference
In-Depth Information
The San Antonio Statement on Brominated and Chlorinated Flame
Retardants (DiGangi et al., 2010), agreed upon at the
30th International
Symposium on Halogenated Persistent Organic Pollutants
(DiGangi et al.,
2010), in San Antonio, Texas, summarizes the concerns of expert scientists
onPBDEs.About145scientistsfrom22countriesdevelopedareasonedplea
from the scientific community to consider impacts of the use of halogenated
flame retardants both at present and for the future.
7.4.2 Environmental Sustainability and PBDE
The regulatory process for PBDEs appears to be on track with significant
steps already been taken to phase out their use, as demanded by
environmental sustainability. The decabromo- congener is expected to be
voluntarily phased out in 2014. As with phthalates and BPA, the next step
would be the identification of safe and viable alternatives. Some of these are
already being developed. Again, ensuring the safety of available alternatives
needs to be the critical focus in material substitution. For instance,
hexabromocyclododecane (HBCD) is widely used (23,000 MT in 2011) as
an unregulated flame retardant in polystyrene and EPS foam products
including some food-contact products (at 0.7-2.5% w/w) (Alaee et al.,
2003). It is bioaccumulative and, based on animal studies, is a highly toxic
additive that is listed under the Stockholm Convention on Persistence
Organic Pollutants to be banned for future production and use (Rani et al.,
2014).
Halogen-free flame retardants that can substitute for deca-BDE are
presently available. A 2009 report (Morgan and Wilkie, 2014) identified
several phosphate-based flame retardants well suited for electronic
equipment applications. Adopting these has to be approached with caution
as organophosphorus compounds can also be potentially carcinogenic,
genotoxic, or neurotoxic. As these are also used in other applications
including as plasticizers, their environmental concentrations are already
high (µg/g range in dust (Van den Eede, 2011)).
7.5 ALKYLPHENOLS AND THEIR ETHOXYLATES
(APE)
Worldwide production of APEs is about 390,000 tons, and about 80% of
it is used to produce octyl- or nonylphenol ethoxylate (NPE) nonionic
