This story is brought to you in part by Waterloo Biofilter Systems
TRICLOSAN: BAN OR REGULATE?
By Ronan O'Doherty
It's strange to think that something as innocuous as washing our hands can be considered environmentally damaging.
We're all taught from an early age that cleanliness helps halt the spread of disease. Is it possible that that same cleanliness instinct that's been drilled into us may be responsible for pollution that's detrimental to our wellbeing and the wellbeing of our water systems?
As of December 2016, the Government of Canada has added triclosan to a list of toxic substances on the Canadian Environmental Protection Act (CEPA).Triclosan is an anti-bacterial and anti-fungal agent. It was invented in the 1960s by CIBA, a chemical manufacturing company based in Switzerland. It came onto the market in the early 1970s for use as a surgical scrub.
For decades its use was restricted to hospital and laboratory environments, however in the late eighties and early nineties, its usage skyrocketed as it became a popular additive to many common household products like detergents, toothpaste, pesticides and hand soap.
Fear of germs like the H1N1 virus and SARS has dramatically increased demand for soaps that kill all microbes. Studies have shown however, that using products containing triclosan or similar chemicals is gross overkill. According to a 2005 Food and Drug Administration (FDA) panel, triclosan soaps are no more effective than washing hands with soap and water.
Fe De Leon is a researcher and paralegal at the Canadian Environmental Law Association. She's most active on chemical policy at all levels of government (municipal, provincial, federal and international). She started paying close attention to triclosan in 2012 when the Government of Canada started undergoing an assessment of the agent. Her firm highlighted it as one to watch and started conducting their own research concurrently; releasing a report of their own in 2014 that focused on the Great Lakes.
"We knew triclosan was a problem based on the government's assessment and we also knew that the problem with the process we continue to work within, was that the government was trying to manage the risk instead of just phasing it out," she said.
According to the government assessment," Triclosan is toxic to a variety of aquatic organisms, such as algae, macrophytes, invertebrates, amphibians and fish. Adverse effects that have been observed include reduction in growth, reproduction and survival, and there is evidence of endocrine-disrupting effects at environmentally relevant concentrations. Triclosan can also be highly bio-concentrated in fish, and there is evidence of bioaccumulation in algae and aquatic invertebrates."
It goes on to say that, "The use of triclosan in products used by consumers is the major contributor to releases of Triclosan into the environment in Canada, which results in the continuous release of the substance to aquatic ecosystems via publicly owned wastewater treatment systems."
Furthermore, it adds, "Given the widespread presence of triclosan in water bodies across Canada, including at levels at or near those that can harm aquatic organisms, it is concluded that the ongoing release of triclosan to the aquatic ecosystem is a source of concern to the environment in Canada."
As of publication of this article, the Government's solution to deal with Triclosan is to put in place a pollution prevention plan. De Leon's firm and many other environmental groups across Canada believe that's not nearly enough.
"All they're asking is that when Triclosan is leaving the plant and released into the environment like water, it doesn't exceed a particular concentration limit. What we're concerned about is that there's no call to reduce or eliminate these chemicals but simply to manage the discharge of these chemicals at the end of pipe," De Leon said.
GreenScreen is a tool developed by Clean Production Action in the US. It's used to determine or inform government agencies, industry and the public on the hazards of a chemical. Although not the case in Canada, in the US it's often used to inform policy decisions. According to the results of this tool, we should move away from Triclosan. In the GreenScreen approach, they benchmark the result with a higher mark determining that the product is safest. The scale is from one to four and Triclosan received a benchmark of one, making it very much unsafe. Its possible replacement, triclocarban, scored a two.
Ryan Prosser, a post-doctoral researcher with Environment and Climate Change Canada, doesn't think that it's quite time to panic about triclosan yet.
According to studies he's performed, triclosan isn't very water soluble, with a solubility level of only 1mg/100ml. Prosser says because of its properties, when it get to a wastewater treatment plant it typically ends up with the bio-solids, with only a small amount ending up in the water.
"Typically bio-solids are land applied. Farmers are part of a program where municipalities transport the bio-solids and apply them to (their) fields. Bio-solids have a lot of nutrients, so they improve the farmer's fields."
As concerns over possible contamination to the fields existed, Prosser tested the plants and soil and determined that triclosanwas degraded reasonably quickly by microbial communities within the soil and that plants didn't absorb it to any relevant degree.
"If we think about the best management practices we follow in Ontario and mimic it in a lab, we see very little movement offsite and it is degraded very quickly," Prosser said.
He went on to note that from a water perspective, even at its highest concentration of around 1mg/100ml (which would be rare in his opinion) the concentration needed to have adverse effects on fish, algae and aquatic invertebrates would need to be two to three magnitudes higher.
Prosser did say that one of the serious pitfalls of overuse of triclosan is the risk of bacteria building up antibiotic resistance. An article on Environmental Working Group's (EWG) website describes studies which have shown that some strains of bacteria have already acquired reduced susceptibility to triclosan and that exposing specific bacterial strains to triclosan appears to result in selection favouring bacteria that are resistant to multiple antibiotics.
According to Prosser, another major concern is its persistence. Compared to other PPCPs it doesn't break down quite as easily. That's why it's received more attention. It's not nearly as persistent as a chemical like DDT would be around for decades but it's more likely to stay around for month.
As far as its direct effect on humans goes, Prosser believes it's negligible, saying, "Our exposure from using hand soap for example is more of an issue than the triclosan that's released into the environment. It was present in certain mouthwashes. That's more of a concern than anything that might be in water or agricultural fields. Our exposure from what's been put through water treatment is almost non-existent."
For many environmental groups, triclosan is more of an example that typifies toxic chemicals that we're allowing into our waterways. Mark Mattson is the president of Lake Ontario Waterkeeper. His organisation has been working on triclosan for a while, and he's someone who thinks of the big picture.
"The Great Lakes are a massive experiment for the 44 million people living on its shores... and we have to be wary of how vulnerable it is to our consumer ways. "
As opposed to citizens of New York or Boston, who don't live on a body of water that they rely on for drinkable water, Mattson thinks Toronto and the other Great Lakes cities need to be extra careful with what they allow to be dumped as waste in a giant reservoir that doubles as their drinking water supply.
Mattson believes that the Great Lakes are a unique water body that require special laws. It represents a huge amount of the surface fresh water in the world and is integral to our life and economy.
"With chemicals being put directly into sewage that are going into our drinking water we should have the best sewage treatment plants in the world. But we don't. We instead have assumed that the Great Lakes isso large that they dilute the toxic substances, however dilution is not the solution to pollution."