No clear path for Golden Rice to reach consumers

by Washington University in St. Louis

Rice fields in the Cordillera mountains of northern Luzon, the Philippines. A new study based on surveys and interviews of more than 115 rice farmers in the Nueva Ecija region, part of the 'rice bowl' of the Philippines, finds that that most families at risk for Vitamin A deficiency can't grow Golden Rice themselves, and most commercial farmers won't grow it either. Credit: Glenn Davis Stone, Washington University in St. Louis

Heralded as a genetically modified crop with the potential to save millions of lives, Golden Rice has just been approved as safe for human and animal consumption by regulators in the Philippines. The rice is a beta carotene-enriched crop that is intended to reduce Vitamin A deficiency (VAD), a health problem in very poor areas.

But a new study finds that most families at risk for VAD can't grow Golden Rice themselves, and most commercial farmers won't grow it either.

"Many families with Vitamin A deficient kids don't even have rice land to plant it," said Glenn Davis Stone, professor of sociocultural anthropology and environmental studies in Arts & Sciences at Washington University in St. Louis and co-author of a new paper in the journal Technology in Society. "And those in the mountains won't plant it because it has been bred into the lowland varieties of rice known as IR-64 and RSC-82."

The regulatory approval in the Philippines is a landmark for the scientists who developed Golden Rice for nutritional purposes. It is the first such approval in the developing world. But even after nearly three decades of development, Golden Rice is still beset by problems, according to Stone.

Golden Rice still has to be approved for commercial sale, and it still needs a company to grow marketable quantities of seed. And even then, Stone argues, there is no clear path for the rice to get to poor children.

Stone, an internationally recognized expert on the human side of global agricultural trends, was an early advocate for keeping an open mind about 'humanitarian' GMO crops, such as Golden Rice. Since 2013, he has directed a major Templeton Foundation-funded research project on rice in the Philippines.

Stone's new study is based on surveys and interviews of more than 115 rice farmers in the Nueva Ecija region, considered part of the 'rice bowl' of the Philippines.

Writing in the Feb. 7 issue of The Conversation, Stone and his study co-author Dominic Glover, a rice researcher at the Institute for Development Studies at the University of Sussex, suggest that backers of Golden Rice—and even some economists who have tried to project its health impacts—have made certain flawed assumptions about farmers' willingness to plant the crop.

"The old claim, repeated again in a recent book, that Golden Rice was 'basically ready for use in 2002' is silly," Stone and Glover wrote. "As recently as 2017, IRRI made it clear that Golden Rice still had to be 'successfully developed into rice varieties suitable for Asia, approved by national regulators, and shown to improve vitamin A status in community conditions.'

"The Philippines has managed to cut its childhood VAD rate in half with conventional nutrition programs. If Golden Rice appears on the market in the Philippines by 2022, it will have taken over 30 years of development to create a product that may not affect vitamin levels in its target population, and that farmers may need to be paid to plant."

Genetically modified Golden Rice falls short on lifesaving promises

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More information: Dominic Glover et al, Golden Rice and technology adoption theory: A study of seed choice dynamics among rice growers in the Philippines, Technology in Society (2019). DOI: 10.1016/j.techsoc.2019.101227

Mediterranean sea urchins are more vulnerable than previously thought

by University of Barcelona

The species Paracentrotus lividus is very abundant in the Catalan coasts. Credit: Creu Palacín (University of Barcelona-IRBio)

The sea urchin Paracentrotus lividus, an eatable species of great commercial interest found in the Mediterranean and North-East Atlantic, is more vulnerable than so far believed.

This is stated in a study by the University of Barcelona, the Spanish National Research Council (CSIC) and the University of Tromsø (Norway) on the genetic distribution of populations of this species, led by the experts Marta Pascual, from the Faculty of Biology and the Biodiversity Research Institute (IRBio) of the University of Barcelona, and Xavier Turon, CSIC research professor at the Center for Advanced Studies of Blanes (CEAB-CSIC). The study has been recently published in the journal Diversity and Distributions.

Using a genetic analysis of the populations of this sea urchin, this work assesses its population structure and connectivity as a result of its dispersal ability. Scientists analysed about 250 individuals of Paracentrotus lividus from eleven marine areas, ranging from the French Atlantic coast to the eastern Mediterranean.

Researcher Xavier Turon (CEAB-CSIC) notes that "adult sea urchin barely move," and that dispersal occurs during the larval stage, since "when they are larvae, they swim in the plankton and are carried away by marine currents. We thought they had a high dispersal capability, since they have a long larval lifespan, which lasts for weeks."

What the study reveals is that "the dispersal is not as wide as we expected," says Turon, "and geographical barriers such as the Strait of Gibraltar limit the connectivity of populations. The exchange of sea urchin larvae between different areas is more limited than what we thought."

Another shocking result is that the selection at a local level is having an impact on the genetic make-up of the different populations of urchins. "We found different allele composition among populations," note researchers Marta Pascual and Carles Carreras (UB-IRBio). "When we analysed the genetic sequences in which these differences appeared, we saw that they lay in genes that code for processes related to temperature and salinity." There is a strong selection pressure related to temperature in the Mediterranean, which can have important consequences regarding global warming.

The study reveals there is a progressive adaptation to salinity and temperature from west to east, and that the largest genetic differences are found between populations in the Atlantic and the Mediterranean. In the latter, the populations of western Mediterranean areas are also differentiated from those in the eastern Mediterranean.

Despite being the target of an active fishery, this species is very abundant in the Catalan coasts, since the fishing pressure has removed many of its predators (mainly fish). Urchins are herbivorous and eat seaweeds and seagrasses. With no predators, the populations can grow excessively and can eliminate submarine forests by overgrazing.

There are two main species of sea urchins in the littoral area of the Mediterranean: the eatable species Paracentrotus lividus, and the black sea urchin Arbacia lixula, non-edible. The new study brings new data to consider so as to predict potential future scenarios of how the common sea urchin populations will respond to antagonist pressures of predator removal and fishing, in a context of progressive warming.

Chimera formation could favor the expansion of invasive species in the marine environment

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More information: Carlos Carreras et al, East is East and West is West: Population genomics and hierarchical analyses reveal genetic structure and adaptation footprints in the keystone species Paracentrotus lividus (Echinoidea), Diversity and Distributions (2019). DOI: 10.1111/ddi.13016

Cattle grazing supports biodiversity in Romania

by Sarah Pocock, Fauna & Flora International

The dynamic, mosaic landscapes of southern Transylvania. Credit: Olivia Bailey/FFI

Blocking out the seemingly endless rain, cold and dark of midwinter is no mean feat, but picture this: it's early summer, the days are growing longer, the earth is warming underfoot and meadows are humming with life. Fit to bursting with plants, insects, birds and small mammals, these wildflower havens are a sensory overload. Vibrant yellows, pinks and purples nestle among the fresh greens while the meadow orchestra buzzes, twitters and snuffles its summertime song. 

Wildflower-rich grasslands offer us more than inspirational backdrops and daisy chains, though. Flowers attract pollinators foraging for their next nectar fix, permanent plant cover protects soil stability and enhances the land's capacity to retain and store water, helping to reduce flood risk, and altogether the ecosystems lock up significant amounts of carbon.

Many of these wildflower meadows would not exist without people who, over millennia, shaped the landscape through traditional farming practices including livestock grazing and regular cutting for hay.

These diverse, semi-natural grasslands are now globally threatened, however. The culture shift from low-intensity to industrial-scale agricultural management and the increasing use of chemical pesticides and fertilizers are two of the main threats facing these habitats worldwide. The United Kingdom's wildflower meadows have now almost entirely disappeared—97% have been lost within the last century. Pressure is also mounting on wildflower habitat across the rest of Europe, where—alongside the primary threat of intensifying agriculture—afforestation and land abandonment also contribute to the degradation of once-diverse grassland systems. In a few special areas, however, wildflower havens not only remain—they flourish.

One of these refuges is the Târnava Mare area in southern Transylvania, where centuries of traditional land management have shaped a biodiverse and dynamic mosaic of old-growth woodland, wildflower-rich pastures and meadows and small areas of farmed land, supporting over 1,000 plant and 600 butterfly and moth species and representing some of Europe's most extensive semi-natural lowland grassland. Since 2004, Fundaţia ADEPT, an Anglo-Romanian NGO with which Fauna & Flora International (FFI) has been a partner for over 10 years, has worked to conserve the ecological and cultural uniqueness of this landscape.

The cattle herd are already helping habitat regeneration at Angofa. Credit: Fundația ADEPT

Historically, dairy cattle grazed these pastures, but industry uncertainty and low economic returns led many farmers to switch to sheep farming. The once species-rich grassland of Angofa valley suffered greatly where sheep had overgrazed, leaving an eroded habitat taken over by invasive weeds and with dwindling floristic diversity.

To prevent further deterioration, ADEPT purchased 200 hectares of land within the Angofa valley, grant-aided by FFI's Halcyon Land & Sea Fund, supported by Arcadia—a charitable fund of Lisbet Rausing and Peter Baldwin—and FFI's wider supporter network. The plan was to reinstate cattle grazing—a much more sympathetic way to manage grasslands than sheep farming, as cattle graze less closely and selectively than sheep and their trampling habits open up coarse vegetation and leave tussocks of longer grasses which benefit insects and small mammals.

Generous donations from individual UK supporters and support from FFI enabled the purchase of a 60-strong herd of Aberdeen Angus beef cattle and, since their arrival at Angofa in March 2018, once degraded pastures are already showing encouraging signs of regeneration. Floristic diversity is on the rebound and it is hoped that with this habitat recovery, birds such as corncrake, butterflies including the large blue and a whole host of other insects and small mammals will once again thrive here.

Now a healthy and established herd, the cattle are not only helping to restore the land—they also offer a viable, profit-making economic model which can be scaled across other Transylvanian communities and the wider Carpathian region.

The Angofa farm's profits from 2019 will be reinvested in the farm and will support ADEPT's other core conservation activities. The purchase and sensitive management of this land has prevented the loss of an important refuge for biodiversity and we look forward to further supporting ADEPT as they continue to protect the nature-rich farming landscapes of Transylvania.

Four steps to make your lawn a wildlife haven – from green desert to miniature rainforest

How a plant‑rich diet can help fight climate change and reduce stress

by Kathleen Kevany, The Conversation

Regularly changing crops can help keep nutrients and carbon in the soil. Credit: Shutterstock

We have heard a lot about climate change, and we need to hear more about what we can do, individually and collectively, to address it.

How might we confront the challenges of the climate crisis—the environmental concerns, mental anguish, physical ailments and political entrenchment? How might we bring about the critical change that these times call for?

Plant-based diets offer one way forward—they have the potential to simultaneously help tackle the climate crisis, prevent disease and improve mental health.

For the past two decades, I have worked with colleagues to examine social, environmental and political challenges from a holistic perspective called systems thinking. This approach focuses on the way a system's components interact and how different systems relate to one another. The approach helps identify systems solutions to current needs—and those in the future.

I have recently edited a book—Plant-Based Diets for Succulence and Sustainability —that offers systems analyses to address many of the drivers of the global climate crisis.

Plant-based diets for climate

An international coalition of scientists has recently measured, mapped and modelled solutions for stopping global warming, including managing refrigerants, building onshore wind turbines, reducing food waste and shifting to plant-rich diets.

Animal foods demand a greater input of resources like water, fuel and land, and contribute to deforestation and biodiversity loss, than plant-based foods. For example, the carbon cost of beef is about 20 times more per gram of protein than it is for beans.

More sustainable land-use practices, a focus on restoring ecosystems and a shift away from resource-intensive diets could help decrease greenhouse gas emissions from food production. For example, cultivating plant-based foods, like dry peas and lentils in crop rotations enable the channeling of resources, like water, land and fuel, to increase the amount of food produced, reduce emissions from agriculture while enhancing soil health.

Eating to tackle disease

There's compelling evidence to suggest that plant-rich diets offer health benefits.

Large studies of people living in western countries who consume diets richer in vegetables, legumes and grains show some protective effects. They are less likely to be overweight or suffer from ischemic heart disease (the build-up of plaque in the arteries) and are less likely to die from cardiovascular disease and kidney disease, for example, compared to people who regularly consume meat.

Mediterranean-type diets, which emphasize plant-based foods and protein sources, can decrease the risk of heart disease.

Mediterranean diets are rich in vegetables, fruits, herbs, nuts, beans and whole grains, and include small amounts of dairy, poultry, eggs and seafood. Credit: Shutterstock

Nutrition for mental health

Canadians rank climate change as one of their biggest concerns for the future. This is leading to the phenomenon of eco-anxiety—feelings of intense anxiety or stress about a future where climate change will dramatically disrupt life as we know it.

Being angry or anxious about climate change isn't a pathology. It is normal to have reactions to adversity—like feeling grief when a body of water is polluted or loss when a woodlot is cut down—and such reactions should not be considered abnormal or dysfunctional.

An individual's response to that anxiety can have positive impacts on the planet. One might fly less, choose a plant-based diet or walk more. These actions can also offer additional benefits, like better health, more pride of place and a greater sense of personal efficacy.

Frances Moore Lappé, author of Diet for a Small Planet, recently advised readers not to give into despair but to take suitable action.

When eco-anxiety takes on the forms of depression, paralysis or loss of well-being, however, it becomes more troubling. Yet some research shows that what you eat can affect your mood.

One study of healthy Seventh Day Adventist men and women found that vegetarians reported less negative emotions than those who ate an omnivorous diet. Another study found vegan men were less anxious and vegan women had lower stress scores than those who did eat meats.

Governments need to lead

Governments can adopt policies and practices that support more efficient, ethical and sustainable production of food. Not only would this help reduce emissions from food systems, showing environmental leadership would alleviate some of the anxiety mounting in many citizens.

Some governments, industries and citizens have been acting together for greater sustainability by envisioning and articulating a Green New Deal for Canada.

The collection of evidence is compelling that reducing food waste, increasing plant-rich diets, practicing conscious consumption and improving food systems can help to improve mental and physical health and displace anxiety.

Collectively and individually we can heed the best in science, while also bringing out the best in humanity, by adopting proven strategies to address these pressing challenges.

Rising eco-anxiety means we should address mental health alongside food security

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Provided by The Conversation 

No food, no fuel, no phones: Bushfires showed we're only ever one step from system collapse

by Anthony Richardson, The Conversation

Credit: Australian Navy

This summer's bushfires were not just devastating events in themselves. More broadly, they highlighted the immense vulnerability of the systems which make our contemporary lives possible.

The fires cut road access, which meant towns ran out of fuel and fell low on food. Power to towns was cut and mobile phone services stopped working. So too did the ATMs and EFTPOS services the economy needs to keep running.

In a modern, wealthy nation such as Australia, how could this happen?

In answering this question, it's helpful to adopt "systems thinking." This approach views problems as part of an overall system, where each part relates to each other.

In other words, we need to look at the big picture.

Through a systems lens

Systems are everywhere, from the coral ecosystem of the Great Barrier Reef to the vast technology networks of global financial markets. In a human sense, social systems range from the small, such as a family, to large organizations or the national or global population.

The systems I mentioned just now are "complex" systems. This means they are connected to other systems in many ways. It also means a change in one part of the system, such as a bushfire in a landscape, can set off unpredicted changes in connected systems—be they political, technological, economic or social.

All complex systems have three things in common:

1. they need a constant supply of energy to maintain their functioning
2. they are interconnected across a range of scales, from the personal and local to the global and beyond
3. they are fragile when they have no "redundancy," or Plan B.

The case of East Gippsland

To better understand a complex system collapse, let's examine what happened in Victoria's East Gippsland region, particularly the coastal town of Mallacoota, during the recent fires.

This case demonstrates how one trigger (in this case, a bushfire) may start a cascade of events, but the intrinsic fragility of the system enables total collapse.

Transport-wise, neither East Gippsland nor Mallacoota itself are physically well connected. Fires cut both the only transport connection to East Gippsland, the Princes Highway, and the lone road out of Mallacoota.

Smoke haze prevented air transport. This meant the only way out was by sea, in the form of intervention by the Australian Navy.

Second, there were no reserves of food, fuel, water, medical supplies or communications at hand when the fires had passed. Supplies ran so low there were reports of a looming "humanitarian crisis".

Defence and civilian authorities clear a tree blocking a road near Mallacoota in January. Credit: Aus. Dept Defence

These shortages are no surprise. In Australia, as in most developed countries, food and fuel distribution systems run on a "just in time" model. This approach, originally developed by Japanese car manufacturer Toyota, involves organising supply networks so materials are ordered and received when they are needed.

Such systems remove the need to store excess goods in warehouses, and are undoubtedly efficient. But they are also extremely fragile because there is no redundancy in the system—no Plan B.

Implications for Australia

Australia as a whole is, in many ways, just as fragile as Mallacoota.

We import 90% of our oil—a figure expected to rise to 100% by 2030. Much of that fuel passes through the Straits of Hormuz and then through the Indonesian archipelago. We have few alternative routes.

Nor do we maintain sufficient back-up reserves of fuel. Australia is the only International Energy Agency (IEA) member that does not meet the obligation to keep 90 days of fuel supplies in reserve.

As East Gippsland and Mallacoota have shown, many other connected systems, such as food distribution networks, are critically dependent on this fragile fuel supply.

A close shave

On January 3 this year—the very day HMAS Choules evacuated people from Mallacoota – the US killed Iranian general Qasem Soleimani by drone strike.

If Iran had responded by disrupting the flow of oil through the Strait of Hormuz, throwing global oil supply into turmoil, Australia may have faced nationwide fuel shortages at the height of the bushfire crisis.

Late last year Australia reportedly had 18 days of petrol, 22 days of diesel and 23 days of jet fuel in reserve.

A global fuel crisis was avoided only due to restraint by both the US and Iran. Australia might not be so lucky next time.

The need for reserves

Our communities, especially in bushfire-prone areas, need more redundancy to make them resilient to disasters. This might mean towns storing water, non-perishable food, blankets, medical supplies, a generator, a satellite phone and possibly fuel, in protected locations.

More broadly, Australia needs a national fuel reserve. This should be in line with the IEA's 90-day obligations. In December last year, Australia reportedly had just 54 days' worth of reserves.

The federal government has recently looked to bolster reserves through possible deals with the US and Holland. But overseas supplies will not be very helpful in an immediate crisis.

The implications of the bushfire crisis are clear. At a national and individual level, we must improve the resilience of the systems that make our daily life possible.

Thousands trapped on Australia beaches encircled by fire

As big cities get even bigger, some residents are being left behind

by Sajeda Tuli and Shakil Bin Kashem, The Conversation

Credit: Cromo Digital/Shutterstock

The concentration of growth in major cities, driven by the knowledge economy and the changing nature of work, may also increase their social inequality. Our research looked at cities in the US and Australia. We compared measures of the knowledge economy and social vulnerability of their metropolitan areas and plotted them together. 

Cities with above-average knowledge economies and below-average levels of social vulnerability are better placed to cope with the dual challenges of technological change and social inequality. Australia has only two cities in this category.

Australia's biggest cities score high on knowledge economy capacity but also have high levels of social vulnerability. And some cities score poorly on both measures. This makes them doubly vulnerable to economic change and social inequality.

Winners and losers in the one city

One factor in these contrasting trends of concentrated growth and rising social vulnerability is the changing nature of work. Cities are the site of the Fourth Industrial Revolution as the world economy clusters in major centers. It's driven by the benefits of agglomeration – the productivity and efficiency gains from having many producers and people located near one another.

Already, 600 cities generate 60% of global economic output. The world has 21 mega-cities of over 10 million people compared to three in 1975. By 2040, 65% of the world population will live in cities.

Knowledge Cities Index (KCI) and Social Vulnerability Index (SVI) of US cities. Higher KCI is to the right of the average line, higher SVI is above the average line. Author provided

In the US, jobs were lost all over the country during the Great Recession of 2007-09. But the recovery is concentrated in 25 urban cores. Some 60% of US job growth is expected to take place in these centers.

This over-concentration of employment opportunities may lead to social inequality and vulnerability within these cities. At the same time, other older and smaller cities have struggled to revamp their economies.

In Australia, too, the top five capital cities are growing bigger. Growth is dominated by Sydney and Melbourne, but economic and social inequalities are increasing.

Despite economic growth, homelessness is increasing in both Australian and US cities. For some US cities such as Los Angeles, Seattle and San Francisco, it is at a tipping point. These same cities are home to the most educated and richest citizens too.

How do US and Australian cities compare?

Combining various socioeconomic and demographic data (including Australian Census, US Census, American Community Survey and IPUMS data) at the metropolitan level, we created a Knowledge Cities Index (KCI) and Social Vulnerability Index (SVI). The chart below plots the KCI and SVI scores of 104 US metropolitan centers.

Knowledge Cities Index (KCI) and Social Vulnerability Index (SVI) of Australian cities. Higher KCI is to the right of the average line, higher SVI is above the average line. Author provided

The middle two lines show the averages of these scores. Cities with higher knowledge city scores (right side of the line) and lower social vulnerability scores (below the line) are better placed to cope with the dual challenges of technological shift and social vulnerability. These cities include New York-Newark-Jersey City, Chicago-Naperville-Elgin, Baltimore-Columbia-Towson, and Boston-Cambridge-Newton.

The chart below shows only two Australian cities—Brisbane and Adelaide—are in this category.

Cities with higher KCI scores but also higher SVI scores include Sydney, Melbourne, Canberra and Perth.

Some major US metro areas in this category are San Jose-Sunnyvale-Santa Clara, Washington-Arlington-Alexandria, North Port-Sarasota-Bradenton, Miami-Fort Lauderdale-West Palm Beach and Washington-Arlington-Alexandria. These cities are doing well in terms of knowledge generation and innovation, but have greater inequality and social disparities among their residents. These cities need strategies and policies to make themselves more inclusive and resilient.

The benefit of agglomeration economics may concentrate and benefit knowledge workers while segregating them from the rest of the society and increasing inequality.

The map below shows the concentration of knowledge industries in Sydney. Sydney CDB has the highest concentration for most of the knowledge industries, except high-tech manufacturing.

Distribution of knowledge industries in Sydney metropolitan area. Data: ABS, 2016, Author provided

We found some cities with very low KCI scores and high SVI scores. US examples include McAllen-Edinburg-Mission, Las Vegas-Henderson-Paradise, Portland-South Portland and Memphis. In Australia, cities in this category include Sunshine Coast, Bunbury, Central Coast, Townsville and Gold Coast-Tweed Heads.

These cities are the worst off. Their lack of knowledge capacities and high social inequality make them highly susceptible to both technological shifts and social vulnerability. Solid strategies and policies are needed to increase the knowledge bases and improve the social conditions of these cities.

What does this mean for policy?

One suggested solution is polycentric cities. But this approach depends on overcoming the challenge of coordinating transport with land uses.

The knowledge economy is increasingly important for cities to compete in the age of automation. But it can also compound the risk of increased social exclusion or vulnerability. Affected cities may then become less capable of withstanding impacts on other frontiers of social change.

The belligerent rate of automation may make the situation worse. Despite its cost-efficiencies, automation has other human costs.

These impacts require policy intervention. The two indices of our study examine both the urban opportunities and the downsides of inequality and social vulnerability that the knowledge economy creates. The policy challenge will be how to make socially vulnerable populations more resilient to the changing nature of work and reduce its negative impacts.

A blanket ban on toxic 'forever chemicals' is good for people and animals

by Jonathan Van Hamme, The Conversation

PFAS are a class of about 5,000 compounds found in firefighting foam, flame retardants and non-stick cookware. Credit: Shutterstock

Lowe's recently joined the Home Depot and other major retail chains in phasing out the sale of products treated with poly- and perfluoroalkyl substances, toxic chemicals more commonly known as PFAS. Specifically, Lowe's said it would stop selling indoor residential carpets and rugs treated with the PFAS by the end of 2019.

PFAS are a family of chemicals known for their non-stick, water-repellent and stain-resistant properties. They are used in cookware, clothing, carpets, cosmetics, and military and industrial applications.

But PFAS are persistent and have been detected in drinking water, in soil, rain, fog and ice, and in humans, plants and animals. Even polar bears and ringed seals in the Arctic have PFAS in their blood. A recent report found that almost all U.S. drinking water sources may be contaminated with PFAS, and the chemicals have been found to be widespread in Canadian rivers and creeks. Despite the evidence that PFAS cause a range of health problems, chemical companies often contradict those claims.

Although some countries have banned some types of PFAS, many remain on the market and new ones are regularly introduced. Perhaps it is time to ask whether wider bans on PFAS production and use are needed.

Non-stick for 80 years

PFAS are slow to break down in the environment. This stability can be traced to the strong bonds between fluorine atoms and chains of carbon atoms in the backbone of the molecules.

The first fluoropolymer was synthesized in Germany in 1934. It was soon followed by the accidental synthesis of polytetrafluoroethylene (PTFE) in 1938 by a chemist working for the chemical company DuPont. Within a few years PTFE was commercialized as the non-stick coating Teflon, and applied to everything from pans to paints.

Despite the history of PFAS, and the introduction of new products every decade since 1940, it was not until the turn of the century that PFAS manufacturers, academics and regulators had the analytical tools to begin to understand the pervasive nature of PFAS in the environment and the risks to human health.

Health problems

People are exposed to PFAS through food and water, and by inhaling dust. The chemical has been found in the blood of infants, young children and their mothers. Those working in the PFAS manufacturing industry or living near chemical plants have higher rates of exposure.

These compounds can build up, or bioaccumulate, in the tissues of people and other animals, with a preference for the liver, kidneys and blood. They are water soluble, meaning that they are excreted in urine, feces and in breast milk.

Recent laboratory tests found drinking water in dozens of U.S. cities is contaminated with PFAS chemicals at levels exceeding safety standards. Credit: Shutterstock

Research has linked PFAS to a variety of toxic effects, including liver damage, decreased fertility, thyroid disease, testicular and kidney cancer and a decreased immune response to vaccines. Growing concern about the potential health risks of PFAS has led some companies to discontinue their use.

On the manufacturing side, the 3M Company was the first to announce in 2000 that it would stop making perfluorooctane sulfonate (PFOS), the active compound in Scotchguard and other products, and one of the older types of PFAS. At the time, the U.S. Environmental Protection Agency said it was on the verge of taking steps to remove the product from market because of the risk it posed to the environment and human health.

Despite evidence to the contrary, including company records that have been made public in lawsuits, some in the chemical industry continue to argue that the chemicals do not pose human health risks.

Only a small fraction of PFAS have been tested for human health and safety before they were released to the market. With an estimated 3,000-5,000 untested PFAS being used in products today and only 75 PFAS identified by the EPA for future toxicity testing, it is not difficult to muddy the waters of evidence.

Regulations for public good

Hundreds of industrial, aviation and military sites across North America are contaminated with PFAS, and are at risk of polluting drinking water and food sources. By one estimate more than 110 million people in the U.S. may be drinking PFAS-contaminated water.

From a regulatory perspective, most of the attention has been placed on the two most common types, PFOS and perfluorooctanoic acid (PFOA).

Canada declared PFOS a toxic substance in 2008, and it was added to the Stockholm Convention on Persistent Organic Pollutants in 2009. The U.S. Environmental Protection Agency has been working with companies for more than a decade to stop the production and import of long-chain PFAS, including PFOS and PFOA.

The U.S. House of Representatives approved a bill in January that would regulate PFAS in drinking water, and the EPA has established a database to map the known health effects of PFAS. Although Canada lists drinking water screening values for 11 types of PFAS, it also warns that only "PFOS and PFOA have been studied sufficiently" to develop guidelines to protect Canadians' health.

Companies continue to introduce new types of PFAS they say are safer, although studies show that they may not be. In addition to the health risks these chemicals pose, they persist in the environment because they cannot be broken down by natural biochemical processes. As part of my research, I study bacteria and fungi that might be used to clean up environments contaminated with PFAS chemicals.

It is time for government to ban all long-chain PFAS, and forever eliminate these forever chemicals from our ecosystems.

Fecal excretion of PFAS by pets

Provided by The Conversation 

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