Dear Ms Christene,

Julia mentions the size as from 20 micrometer to 5 millimeter.

The theme of this year's World Environment Day (5 June) is "Beating Plastic Pollution."

Can you please get me some publications on how we can stop the plastic pollution?
Canada must have developed some publications.

Regards,

F H Mughal

Dear Mr. Mughal,

I thought the range of microplastics had an even smaller upper threshold, but NOAA defines it as having a length smaller than 5mm.

It surprises me to hear about the different places where plastic and microplastics are found, it really underlines the extent of plastic use, plastic waste generation, and plastic disposal.

My masters' thesis focused on glaciology, and so I keep up with news about the cryosphere - and this field gets affected too, as microplastics were recently found in Arctic sea ice cores . This is another issue I will definitely keep up with.

Thank you again for this interesting exchange of resources,

Christene

Dear Ms Christene,

That was an interesting brief background of your work.

Moving on from microplastic (how do you define microplastic?) to just plastic, you must be aware that a plastic bag was found in Mariana Trench, 36,000 ft below the surface. Kindly see this link:
weather.com/science/environment/video/ri...s-of-plastic-bottles

Regards,
F H Mughal

Dear F H Mughal and Elisabeth,

I have never formally done any research in this area, however one of my friends did her thesis at the University of Waterloo on this topic (measuring the presence of microplastics, not only in water but also in the air); another friend of mine is training to work as a WWTP operator in Canada – this topic sometimes comes up in our conversations. I am generally interested in keeping up with water-related issues in Canada – I think although Canada houses about 7% of the world’s freshwater sources, we cannot ignore the challenges that could have a negative impact, and microplastics are one of them.

I have also only heard of membrane bioreactors (MBRs) before. Julia Talvitie also published a a paper in 2017 where 4 different removal methods were tested: MBR, rapid sand filter, dissolved air flotation and disc filter. In a recent conversation I was having, we talked about how incorporating MBRs into WWTPs would also require additional flow control – if the flow is too turbulent, there is the risk the membranes may get clogged. We don’t exactly know how the whole system is designed, but it could be a design consideration.

Thank you again for sharing this report and Julia Talvitie’s work!

A interesting doctoral dissertation is available at aaltodoc.aalto.fi/handle/123456789/30720
which, I'm sure Ms Christene would love to read. The title is Wastewater treatment plants as pathways of microlitter to the aquatic environment, and it is by Julia Talvite.

On a lighter note, Julia says in preface (last 3 lines), while thanking her husband:

Not only did you fund the final year of my PhD (you even put the gasoline in my car when I needed to go sampling!), but you were my loyal (and cheap!) research assistant whenever I needed one. I am forever in your debt (but never be able to pay back). I love you and promise never to do PhD again.

Though Julia promise never to do PhD again, I'm sure Ms Christene will do her PhD11:)

F H Mughal

Great responses, Christene! How come you know so much about this? Was it part of your Masters thesis perhaps?

Mughal: I would guess that membrane filtration would remove microplastics from wastewater. So membrane bioractors could be a suitable technology (see: en.wikipedia.org/wiki/Membrane_bioreactor). But it's expensive of course. The more advanced the treatment, the more expensive it gets.

Regards,
Elisabeth

Dear Ms. Christene,

Thanks for your enlightened response. Just one small point:

You say: "Possible solutions also include retrofitting WWTPs with technologies to remove microplastics." Could you kindly elaborate on those "technologies" for removal of microplastics.

Regards,
F H Mughal

Dear Mr. F H Mughal,
at the moment, there does not seem to be any manual/legislation or recommendations on how to deal with microplastics in Canada.

Control at the source has been highlighted as an important factor in limiting the inflow of contaminants into a WWTP (and into its effluent). The use of microbeads in toiletries and cleaning products, which was a source of microplastics, is gradually being banned : the regulation was first proposed in November 2016 and then officially published in June 2017. Since January 2018, the import and manufacture of toiletries containing microbeads have been prohibited. This upcoming July 2018, sales of such products will be prohibited. This has been happening in the past year and is still being implemented, and so it will still take time until the effects of this ban can be assessed, to explore further source control options. Other countries are at about the same stage as well . Other sources of microplastics include acrylic or polyester microfibers used in clothing (or other fabrics), however these have not undergone any control or been put under a ban of any sort yet.

From what I gather from this report, the WWTP operators, managers and researchers surveyed are all concerned about the presence of microplastics. Possible solutions also include retrofitting WWTPs with technologies to remove microplastics. However further regulations on a high level have yet to follow, as it seems we are still in the phase of understanding the extent of this problem. I think this will be an interesting issue to follow in the upcoming years, maybe in the likes of how we’ve followed the regulation of CFCs and BPA.

Dear Ms. Christene,

I'm glad that you brought up the topic of microplastic. I'm also interested in it as, here, the single-use plastic items have created nuisance.
As someone said, there are more plastics in the oceans than the stars in the Milky Way!!

Is there a Canadian manual/report on how to deal with this problem?

Regards,
F H Mughal

Thank you for sharing this new report. As a Canadian citizen, I am glad to see the Ministry of Environment and Climate Change invest in understanding the challenges in this domain, and to see concrete decisions and actions taken across the country to enhance the sustainability of our WWTPs.

From a policy perspective, it is interesting to see how decentralized Canada is when it comes to its water-related legislation. Indeed, treatment levels vary among provinces (as in Figure 1.1 of Supporting Document 2), as federally, there is no imposed level of treatment required, and everything is regulated provincially and executed municipally. It was furthermore interesting to compare it to the EU, which in contrast seems to have more unified requirements already. Another comparison with regards to treatment levels pertains to the minimum level to achieve – in the EU, the minimum level of treatment in 97% of the jurisdictions is the tertiary level, whereas in Canada, tertiary treatment is rare (it dominates in the provinces of Alberta and Saskatchewan, however in the rest of the country, ~10% of the jurisdictions will reach tertiary treatment). From my perspective, due to the population density, water stress is higher in Europe than in Canada, hence the more urgent need for stricter regulations regarding wastewater effluent quality.

I am also interested in the growing level of focus on microplastics, which have indeed gained more attention in the past 4 years. Surrounded by important water bodies, it is indeed in Canada’s best interests to have a close look at this issue, e.g.:

- On the Pacific coast, the federal Fisheries and Ocean department invested in research on microplastics in the Pacific ocean
- For the Great Lakes, researchers at the University of Waterloo performed up-to-date review of the state of research in this domain
- On the Atlantic coast, researchers at the Mount Allison University are keeping up with research across the rest of the country and investigating the presence of microplastics in freshwater systems

Canada has implemented bans on products that generate these microplastics, and so I look forward to observing what the results of these bans will be in the upcoming years.

Canada’s Challenges and Opportunities to Address Contaminants in Wastewater

Canadian Water Network recently conducted a national review of emerging contaminants in municipal wastewater and, how to address them. An expert panel was appointed and asked to consider three critical questions:

1. Which wastewater contaminants do we need to worry about most, now and in the future?
2. What are the options for Canadian communities to address these contaminants through wastewater treatment?
3. What are the important opportunities and trade-offs involved in treatment choices, including resource recovery, cost implications, socio-economic and cultural fit, and related issues like greenhouse gas emissions?

The expert panel consulted more experts across Canada, and produced an excellent report: Canada’s Challenges and Opportunities to Address Contaminants in Wastewater.

In the report, the expert panel:

1. Identifies where wastewater treatment represents a particularly effective approach to protecting human health and the environment
2. Articulates key opportunities and implications for future wastewater treatment in Canada
3. Provides a blueprint to inform government policy, regulations and funding

The report gives absorbing glossary. The term contaminant has been used to capture pathogens, nutrients, metals, chemicals and physical constituents generated or concentrated by society, which can potentially pose adverse effects on receiving environments and public health.

Contaminants of emerging concern refers to non-conventional contaminants that have been, or will be, detected in wastewater effluents, and for which the potential risks to public and environmental health are not yet fully understood. These contaminants have also been referred to in various sources as emerging contaminants, emerging substances of concern, trace contaminants, micropollutants or microcontaminants.

Trace organic contaminants refers to the diverse array of organic substances found in wastewater effluents at low concentrations, including endocrine disrupting compounds, pharmaceuticals and personal care products. Although some trace organic contaminants may be contaminants of emerging concern, the latter group also captures other new and uncertain substances, such as microplastics and nanoparticles.

This is interesting:

Wastewater treatment plant (WWTP) is used in this report, although this term is being replaced in some jurisdictions with water resource recovery facility (WRRF), in recognition of a more holistic approach to urban water management. Municipal WWTP refers to a local or regional government or utility, or provincial or Indigenous-owned facility which receives collected wastewater for treatment and release into the environment.

The report: Canada’s Challenges and Opportunities to Address Contaminants in Wastewater, is an excellent, useful and informative report.

The report can accessed at www.cwn-rce.ca/

F H Mughal