How to get people to eat bugs and drink sewage



Disgust may be an impediment to many of us adopting more sustainable lifestyles, from considering alternative foods to drinking recycled water
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Nathan S Consedine, University of Auckland

In wealthy societies we’ve become increasingly picky about what we eat. The “wrong” fruits and vegetables, the “wrong” animal parts, and the “wrong” animals inspire varying degrees of “yuck”.

Our repugnance at fruit and vegetables that fail to meet unblemished ideals means up to half of all produce is thrown away. Our distaste at anything other than certain choice cuts from certain animals means the same thing with cows and other livestock slaughtered for food. As for eating things like insects – perfectly good in some cultures – forget about it.

Disgust has its advantages. Its origins likely lie in the basic survival benefit of avoiding anything that smells or tastes bad. But disgust may also be an impediment to many of us adopting more sustainable lifestyles – from eating alternative sources of protein to drinking recycled water.




Read more:
Eating insects: good for you, good for the environment


Can anything be done about this? The fact that disgust varies between cultures and across ages implies it can. But how?

We set out to answer this by getting a better grip on how disgust works, focusing on disgust in everyday food choices, rather than aversions to the unknown or unfamiliar.

Our research suggests some disgust responses, once set early in childhood, are hard to shift.
But responses involving culturally conditioned ideas of what is “natural” may be modified over time.

Don’t eat that!

Disgust likely began as a powerful “basic” emotional reaction that evolved to steer us away from (and literally eject) potential contaminants – food that smelled and tasted bad. You can think of it as originally being a “don’t eat that” emotion.

The disgust system tends to be “conservative” – rejecting valid sources of possible nutrition that have characteristics implying they might be risky, and guiding us towards food choices that are ostensibly safer. Research by University of British Columbia psychologist Mark Schaller and colleagues suggests people who live in areas with historically high rates of disease not only have stricter food preparation rules but more “conservative” cultural traditions generally.

Is is unclear exactly how or when individual templates for what is disgusting are set, but generally what is seen as “disgusting” is set relatively early in life. Culture, learning and development all help shape disgust.

It’s just not natural!

In our study, we showed 510 adults pairs of “normal” and “alternative” products via an online survey, and asked them how much they would be willing to pay for the alternatives. We also asked them to rate which product was tastier, healthier, more natural, visually appealing and nutritious. Product pairs included:

  • shiny and typically shaped fruits and vegetables vs knobbly, blotchy, gnarled and multi-limbed examples.
  • plant protein foods vs insect-based foods
  • standard drinks vs drinks with ingredients reclaimed from sewage
  • standard medicines vs medicines with ingredients extracted from sewage.
Out of shape: using common fruits and vegetables meant the study’s results were not muddied by responses affected by fear of the unknown.
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Our results show that, even after statistically adjusting for obvious factors like pro-environmental attitudes, those with a greater “disgust propensity” are less willing to consume atypical (weird-looking) products.

This may seem rather obvious but most prior studies have muddled a food’s “novelty” with its possible disgusting properties (by asking people, for example, whether they’d eat bugs). By asking about really common fruits and vegetables, our study shows just how far disgust may reach in influencing what we consume.




Read more:
Neigh-sayers: why we won’t agree to eat a dead horse


As importantly, our results suggest evaluations of a product’s perceived naturalness, taste, health risk, and visual appeal “explains” about half of the disgust effect.

In particular, lack of perceived “naturalness” was a frequently reason for unwillingness to pay for product alternatives. This result was in line with previous studies that have looked attitudes to eating insects or lab-grown meat. This is a promising area for social marketing.

Therapeutic responses

Given evidence about how much of what we consider disgusting is cultural and learned, marketing campaigns could help shift attitudes about what is “natural”. It has been done before. Consider this advertisement to naturalise sugar consumption.

Thinking differently about emotion-eliciting stimuli is termed “reappraisal”. Reappraisal has been shown to reduce disgust effects among those with obsessive compulsive disorder. Desensitisation (repeated exposures) seems less effective in reducing disgust (versus fear) among people with diagnosed phobias, but it may work better among the general population.




Read more:
From disgust to deceit – a shorter path than you might think


Of course, such speculations remain untested and their ultimate success remains unclear.

But it wasn’t so long ago that Western consumers turned their noses up at fermented foods, and the notion of “friendly bacteria” made as much sense as “friendly fire”. More than a decade ago the residents of a drought-stricken Australian town voted against recycling sewage for drinking water. Now the residents of an Australian city accept recycled sewage being pumped back into the city’s groundwater.

Given time, circumstance and a little nudging, a future meal at your favourite Thai restaurant may well involve ordering a plate of insects.The Conversation

Nathan S Consedine, Professor of Health Psychology, University of Auckland

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Australia’s pristine beaches have a poo problem



Raw sewage from 3,500 people in Sydney’s affluent eastern suburbs is discharged directly into the ocean.
Will Turner/Unsplash

Ian Wright, Western Sydney University; Andrew Fischer, University of Tasmania; Boyd Dirk Blackwell, University of Tasmania; Qurratu A’yunin Rohmana, University of Tasmania, and Simon Toze, CSIRO

Australians love our iconic coastal lifestyle. So many of our settlements are spread along our huge coastline. Real estate prices soar where we can catch a view of the water.

But where there are crowded communities, there is sewage. And along the coast it brings a suite of problems associated with managing waste, keeping the marine environment healthy, and keeping recreational swimmers safe.




Read more:
Sewerage systems can’t cope with more extreme weather



Sewage is not a sexy topic. People often have an “out of sight, out of mind” attitude. But where does sewage go, and is it treated and disposed of in the waters that we Australians love?

The bigger the coastal community, the bigger the volume of sewage. Disposal of human waste into the ocean might solve one problem, but we now realise that the “waste” is as precious as the ocean it pollutes.

We should be treating and recycling sewage to a drinkable level.
shutterstock

Understanding the problem from a national perspective

Such problems play out continuously along our coastline. Each isolated community and catchment issue arises and is resolved, often in ignorance of and isolation from similar issues somewhere else.

At present, places where sewage impacts are generating community concern include Merimbula, Warrnambool and, perhaps most bizarrely, Vaucluse and Diamond Bay in Sydney’s affluent eastern suburbs.

It’s hard to believe this location has raw and untreated sewage from 3,500 people discharged directly into the Tasman Sea. Sydney Water pledged in 2018 to fix this unsightly pollution by transferring the flow to the nearby Bondi sewage treatment plant.

Community group Clean Ocean Foundation has worked with the Marine Biodiversity Hub to start the process of viewing outfall pollution – where a drain or sewer empties into the sea – as part of a bigger picture. It’s a first step towards understanding from a national perspective.




Read more:
Curious Kids: Where does my poo go when I flush the toilet? Does it go into the ocean?


Together they have produced the National Outfall Database to provide the first Australia-wide comparison.

The best and worst offenders

Previously the information available to the public was sketchy and often not easily accessed. The database shows how differently Australia manages coastal sewage with information on the outfalls.

Clean Ocean Foundation CEO John Gemmill said:

Water authorities in the main do a great job with severe funding constraints. But they can be reticent to divulge information publicly.

One authority, suspicious of the research project, initially refused to give the location of the outfall, claiming it would be vandalised by enraged “surfies and fishermen”.

Sydney has Australia’s biggest outfall. It provides primary treatment at Malabar, New South Wales, and serves about 1.7 million people. The outfall releases about 499 megalitres (ML) per day of treated sewage, called “effluent”.

That’s about eight Olympic-sized swimming pools of effluent an hour. It is discharged to the Pacific Ocean 3.6 kilometres from the shoreline at a depth of 82 metres.

The cleanest outfall (after sustained advocacy over decades from the Clean Ocean Foundation) is Boags Rock, in southern Melbourne. It releases tertiary-treated sewage with Class A+ water. This means the quality is very suitable for reuse and has no faecal bacteria detected (Enterococci or E.coli).

Recycling sewage

Treated sewage is 99% water. The last 1% is what determines if the water will harm human and environmental health. Are we wasting a precious resource by disposing of it in the ocean?

As desalination plants are cranking up in Sydney and Melbourne to extract pure water from salty ocean, why shouldn’t we also recycle sewage?




Read more:
More of us are drinking recycled sewage water than most people realise


Clean Ocean Foundation has released a report showing it would pay to treat sewage more thoroughly and reuse it. This report finds upgrading coastal sewage outfalls to a higher level of treatment will provide tens of billions of dollars in benefits.

Industry analysis suggests that, for a cost outlay of between A$7.3 billion and A$10 billion, sewage treatment upgrades can deliver between A$12 billion and A$28 billion in net benefits – that is, the financial benefits above and beyond what it cost to put new infrastructure in place.

Then there are non-economic benefits such as improved ecological and human health, and improved recreational and tourism opportunities by use of suitable recycling processes.

What the rest of Australia can learn from WA

Clean Ocean Foundation president Peter Smith said Australia’s key decision-makers now, more than before, have a “golden opportunity” to adopt a sea change in water reform around coastal Australia based on good science and sound economic analysis.

In the context of the drought of southeast Australia, recycling water from ocean outfalls is an option that demands further debate.




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Finally facing our water-loo: it’s time to decolonise sewerage systems


As expensive desalination plants are switched on, Sydney proposes to double the size of its desalination plant – just a few kilometres from massive ocean outfalls that could provide so much recycled water. And to our shame, NSW ocean outfalls are among the lowest in standards of treatment.

Western Australia, on the other hand, leads the push to recycle wastewater as it continues to struggle with diminishing surface water from climate change.

In fact, in 2017 the Water Corporation announced massive investment in highly treated sewage being used to replenish groundwater supplies. Perth now sources 20% of its drinking water from groundwater, reducing its reliance on two desalination plants. A key factor was successful engagement with affected communities.

The discharge of poorly treated sewage to rivers, estuaries and oceans is a matter of national environmental significance and the Commonwealth should take a coordinating role.

Our oceans do not respect state boundaries. The time is ripe for a deliberate national approach to recycling sewage and improved systems to manage outfalls.The Conversation

Ian Wright, Senior Lecturer in Environmental Science, Western Sydney University; Andrew Fischer, Senior Lecturer, University of Tasmania; Boyd Dirk Blackwell, Adjunct Researcher, University of Tasmania; Qurratu A’yunin Rohmana, Research Analyst, University of Tasmania, and Simon Toze, Senior Principal Research Scientist, CSIRO

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Don’t believe the label: ‘flushable wipes’ clog our sewers



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Don’t believe the wipe hype: they can’t be flushed down toilets, not matter what the label says.
SIM Central and South East Asia Follow/Flickr, CC BY-NC

Ian Wright, Western Sydney University

The manufacturer of White King “flushable” wipes has been fined A$700,000 because these are not, in fact, flushable. The wipes, advertised as “just like toilet paper”, cannot disintegrate in the sewerage system, and cause major blockages.

The Federal Court found Pental Products and Pental Limited, which manufacture the wipes, guilty of making false and misleading representations. In particular, Pental claimed that the wipes would break down in the sewerage system, like toilet paper does.




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Ten ‘stealth microplastics’ to avoid if you want to save the oceans


So-called flushable wipes, now sold for everything from make-up removal to luxury toilet paper, are a growing hazard to public health. Sydney Water says 75% of all sewer blockages in the city’s waste-water system involve wipes.

Don’t trust the label

While wipes might look a bit like toilet paper, there are major differences. Wipes are made from a very tough material called “air-laid paper”, and are often impregnated with cleansing chemicals, disinfectants and cosmetic scents.

Air-laid paper behaves very differently in sewers to toilet paper and does not readily disintegrate in water.

A CHOICE demonstration comparing wipes with toilet paper over 20 hours.

When in sewer pipes the resilient wipes have a tendency to entangle with other wipes and create blockages. This is a bit like the knot of tangled clothing sometimes found in the washing machine. Sewerage system managers around the globe seem powerless to prevent the problem.

Sewer blockages caused by wipes look grotesque. Unpleasant work in confined places is required to remove the blockages (some of which is done by hand!). In 2016 Newcastle’s Hunter Water removed an ugly seven-metre snake of wipes and assorted sewage debris, weighing roughly a tonne, from its sewers.

Wither do you wipe?

Wipes become very popular in the 1990s to help in cleaning babies’ bottoms while changing nappies. Since then, many similar products (“wet wipes”, “baby wipes” and “face wipes”) have proliferated well beyond the baby aisle.

Wipes may be advertised for personal hygiene, removing makeup and cleaning hands. Others are marketed for cleaning bathroom surfaces, toilets and other household areas. The marketing of wipes often boasts how easy they are to dispose by simply flushing them down the toilet.

More recently, a booming adult market is expanding their use as a luxury alternative to toilet paper, buoyed by endorsements from celebrities like Will Smith and Will.i.am. Research by Sydney Water found that males in the 15-44 bracket particularly preferred to use wipes rather than toilet paper. The same market survey estimated that a quarter of Sydney Water’s 4.6 million customers flush wipes down the toilet rather than putting them in a bin.

The three Ps

The fine imposed on Pental Products and Pental Limited for their “flushable” wipes is an important signal to others in this growing market.

However, wipes are not the only waste item that people should not flush down the toilet. This issue gained international notoriety in 2017 when Thames Water in London removed a 130-tonne monster sewer blockage, in a difficult and laborious three-week operation. The blockage was an accumulation of solids called a fatberg – a nightmarish combination of wipes, congealed fat, nappies, female sanitary products, and condoms.




Read more:
To fight the fatbergs we have to rethink how we treat sewage waste


Have we forgotten what toilets are for? The Australia Water Association reminds us that they are for the three Ps: pee, poo and paper (toilet paper only).

Perhaps people should visit an Irish website called think before you flush. It lists other common waste objects that should not be flushed, such as cigarette butts, cotton buds, dental floss, hair and unwanted medication. It also advises that a bin be placed in each bathroom.

The ConversationHopefully, packets of wipes will now carry warning labels to advise users not to flush them down the toilet. Just because you can flush something down the toilet does not mean it is good for the environment or society to do so.

Ian Wright, Senior Lecturer in Environmental Science, Western Sydney University

This article was originally published on The Conversation. Read the original article.

More of us are drinking recycled sewage water than most people realise



File 20180307 146650 1v2p3a9.jpg?ixlib=rb 1.1
The Hawkesbury’s waters look beautifully natural but treated sewage makes up to 20% of the river flow where the North Richmond Filtration Plant draws its water.
Karl Baron/flickr, CC BY

Ian Wright, Western Sydney University

The world is watching as Cape Town’s water crisis approaches “Day Zero”. Questions are being asked about which other cities could be at risk and what can they do to avoid running dry. In Perth, Australia’s most water-stressed capital, it has been announced that the city is considering reusing all of its sewage as part of its future water supply.




Read more:
Cape Town is almost out of water. Could Australian cities suffer the same fate?


Drinking recycled sewage is a very confronting topic. But what many people don’t realise is that we already rely on recycled sewage in many Australian water supplies. Even in Australia’s biggest city, Sydney, it is an important part of the water supply. This is because many large towns discharge their treated sewage into the catchment rivers that supply the city.

But Perth is now looking to recycle all of its treated sewage. At the time of writing, the city’s water storages were at a low 35.3%. Cape Town’s reserves, by comparison, are at a critical low of 23.5% – but Perth was close to that point just a year ago when it was down to 24.8%.

Perth has been progressively “drought-proofing” itself by diversifying the city water supply. River flow and storage in dams accounts for only 10% of this supply. Desalination and groundwater extraction provide about 90% of the city’s supply. Only about 10% of Perth’s sewage is recycled, through advanced treatment and replenishment into its groundwater supplies.




Read more:
Is Perth really running out of water? Well, yes and no


Justifiably, many people have concerns about drinking recycled sewage. This reflects long-standing concern about hazards of contaminated water. An example is the devastating waterborne disease of cholera, which claims the lives of more than 100,000 people a year. Cholera is rare in many countries, but is endemic in waters across Africa and much of Southeast Asia.

As wastewater treatment technologies improve and urban populations grow, however, interest in using treated sewage in drinking water supplies has been increasing. No Australian urban water supply currently uses “direct potable reuse” of treated sewage, but the concept is being seriously considered.




Read more:
This is what Australia’s growing cities need to do to avoid running dry


So how is treated sewage being indirectly reused?

There is, however, indirect reuse when water is drawn from rivers into which recycled sewage is discharged upstream. For instance, the catchment of Sydney’s giant Warragamba Dam has a population of about 116,000 people. This includes the large settlements of Goulburn, Lithgow, Moss Vale, Mittagong and Bowral. These communities discharge their treated sewage into the catchment rivers.

Several large towns discharge treated sewage into rivers supplying Warragamba Dam, which holds 80% of Sydney’s water reserves.
popejon2/flickr, CC BY-NC-ND

The New South Wales Environment Protection Authority regulates these discharges, which form a small part of the total annual catchment inflow to the dam. Such recycling of sewage is termed “indirect potable reuse”.

Residents in some parts of northwestern Sydney also drink water that is partly supplied by another form of indirect reuse of treated sewage. The North Richmond Water Filtration Plant extracts and treats water drawn directly from the Hawkesbury-Nepean River. A major contributor to the river flow is treated sewage discharged from upstream treatment plants.

These include plants in the Blue Mountains (Winmalee), St Marys, Penrith, Wallacia, and West Camden. The largest individual discharge of treated sewage to the river in recent weeks is from St Marys Advanced Water Recycling Plant, one of the biggest in Australia. This plant uses advanced membrane technology to produce highly treated effluent before it is discharged into the river.

St
Marys Advanced Water Recycling Plant, one of the biggest in Australia, treats sewage and discharges the water into the Hawkesbury-Nepean River.

Ian Wright, Author provided

Available data are limited, but in the very low river flows in the recent dry summer I estimate that treated sewage comprised almost 32% of the Hawkesbury-Nepean flow in the North Richmond area for the first week of January. The water is highly treated at the Sydney Water-owned North Richmond plant to ensure it meets Australian drinking water guidelines.

Every year the river receives more and more treated sewage as a result of population growth. This is certain to continue, as Greater Sydney is forecast to gain another 1.74 million residents in the next 18 years. Much of this growth will be in Western Sydney, one of the most rapidly growing urban centres in Australia. This will result in more treated sewage, and urban runoff, contributing to the Hawkesbury-Nepean River flow.




Read more:
As drought looms again, Australians are ready to embrace recycled water


Paying for desalination while water goes to waste

However, most of Sydney’s sewage is not recycled at all. Three massive coastal treatment plants (at North Head, Bondi and Malabar) serve the majority of Sydney’s population. These three plants discharge nearly 1,000 million litres (1,000ML) of primary treated sewage into the ocean every day. That is roughly an Olympic pool of sewage dumped in the ocean every four minutes!

Perhaps if Sydney was as chronically short of water as Perth there would be plans to recycle more of its sewage. Instead, Sydney has adopted desalination as a “new” source of drinking water, rather than treating larger volumes of sewage for any form of potable reuse.

Sydney’s desalination plant sits idle about 10 kilometres south of the Malabar treatment plant. It has a capacity for supplying 250ML a day. Even though it isn’t supplying water now, it is very expensive. In 2017, the privately owned plant, sitting on standby, charged Sydney Water A$194 million.

Only when Sydney’s storages fall below the trigger of 60% will the plant supply drinking water. With storages at 76.5%, the plant will not operate for a while.


The Conversation


Read more:
The role of water in Australia’s uncertain future


Ian Wright, Senior Lecturer in Environmental Science, Western Sydney University

This article was originally published on The Conversation. Read the original article.