Siloxanes facing test in Canada
The Canadian government has announced a plan to investigate the possible
elimination of several chemicals, including D5, the main ingredient in
GreenEarth drycleaning solvent.
The proposal comes as part of the Chemicals Management Plan of Environment
Canada and Health Canada and launches a process that could take years to reach
a conclusion. The May 17 announcement included preliminary findings for 16 chemical substances identified as high
priorities for action under Batch 2 of the Chemicals Management Plan.
“Our initial assessment shows that four of these chemicals should be kept out of
our environment and as a result we will be working with stakeholders to stop
the release of these substances at the source,” said John Baird, Minister of the Environment.
In addition to GreenEarth, D5 (deca-methylcyclopentasiloxane) is used as an
ingredient in beauty and personal-care products. In fact, its use in
drycleaning is “a drop in the bucket” compared to its other uses, said Timothy Maxwell, vice president of GreenEarth
Cleaning Solutions. He said there are about 25 GreenEarth machines operating in
Canada out of approximately 3,000 drycleaners throughout the nation.
In drycleaning, very little D5 is released into the environment, he said, but
its widespread use in other products may be one of the reasons the ministers of
Environment and Health want, in their words, “to initiate discussions with stakeholders on the development of a risk
management approach.”
The Canadian officials said their concern was not based on risk to human heath
but rather on the fact that D5 is persistent in air, water and sediment, and “has a high potential to accumulate in aquatic organisms and some potential to
biomagnify in terrestrial food-chains.”
“Sediment toxicity data and mammalian studies also suggest that exposure to D5
may cause long-term adverse effects on sediment-dwelling organisms and
organisms in the terrestrial compartment,” Canadian officials said.
GreenEarth’s Maxwell said there will initially be a 60-day comment period to respond to the
Canadian government’s concerns but that he could foresee a process of up to ten years before the
issue is resolved.
“I’m confident that the questions are being answered and cooler heads will prevail,” Maxwell said.
The Silcones Environmental, Health and Safety Council responded to the Canadian
government’s announcement with a press release that said, “The available science shows that D4, D5 and D6 can be safely used in appropriate
applications when used in accordance with accepted health and safety
principles.”
“We are concerned that the draft screening assessments for D4, D5 and D6 propose
environmental conclusions that do not accurately reflect the large amount of
data on these substances,” SEHSC said.
That data, SEHSC said, “do not support the proposal that D4, D5 and D6 are persistent, bioaccumulative,
toxic, and CEPA Toxic. Nor does the available science support the suggestion
that these materials may behave like persistent organic pollutants and may have
an immediate or long-term harmful effect on the environment or its biological
diversity.”
SEHSC noted that more than 130 studies have been performed on the health and
environmental impacts of silicones, concluding that they do not pose an undue
risk to the environment and are safe for use in appropriate cosmetic,
industrial, and consumer product applications when used in accordance with
accepted health and safety principles.
SEHSC said it is conducting additional studies on the environmental fate of D4,
D5, and D6 and it “will continue to work with Canadian government agencies to ensure that questions
relating to silicon-based materials are answered.”
Environment Canada and Health Canada have added 85 chemicals, or chemical
groups, including perchloroethylene, to the list of toxic substances since
1999. Of these, only ten substances have been targeted for virtual elimination.
All other listed chemicals have been subject to full life cycle management.
