Why Are Autism Rates Steadily Rising?
Stefania Sterling was just 21 when she had her son, Charlie. She was young and healthy, with no genetic issues apparent in either her or her husband's family, so she expected Charlie to be typical.
"It is surprising that the prevalence of a significant disorder like autism has risen so consistently over a relatively brief period."
It wasn't until she went to a Mommy and Me music class when he was one, and she saw all the other one-year-olds walking, that she realized how different her son was. He could barely crawl, didn't speak, and made no eye contact. By the time he was three, he was diagnosed as being on the lower functioning end of the autism spectrum.
She isn't sure why it happened – and researchers, too, are still trying to understand the basis of the complex condition. Studies suggest that genes can act together with influences from the environment to affect development in ways that lead to Autism Spectrum Disorder (ASD). But rates of ASD are rising dramatically, making the need to figure out why it's happening all the more urgent.
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Indeed, the CDC's latest autism report, released last week, which uses 2016 data, found that the prevalence of ASD in four-year-old children was one in 64 children, or 15.6 affected children per 1,000. That's more than the 14.1 rate they found in 2014, for the 11 states included in the study. New Jersey, as in years past, was the highest, with 25.3 per 1,000, compared to Missouri, which had just 8.8 per 1,000.
The rate for eight-year-olds had risen as well. Researchers found the ASD prevalence nationwide was 18.5 per 1,000, or one in 54, about 10 percent higher than the 16.8 rate found in 2014. New Jersey, again, was the highest, at one in 32 kids, compared to Colorado, which had the lowest rate, at one in 76 kids. For New Jersey, that's a 175 percent rise from the baseline number taken in 2000, when the state had just one in 101 kids.
"It is surprising that the prevalence of a significant disorder like autism has risen so consistently over a relatively brief period," said Walter Zahorodny, an associate professor of pediatrics at Rutgers New Jersey Medical School, who was involved in collecting the data.
The study echoed the findings of a surprising 2011 study in South Korea that found 1 in every 38 students had ASD. That was the the first comprehensive study of autism prevalence using a total population sample: A team of investigators from the U.S., South Korea, and Canada looked at 55,000 children ages 7 to 12 living in a community in South Korea and found that 2.64 percent of them had some level of autism.
Searching for Answers
Scientists can't put their finger on why rates are rising. Some say it's better diagnosis. That is, it's not that more people have autism. It's that we're better at detecting it. Others attribute it to changes in the diagnostic criteria. Specifically, the May 2013 update of the Diagnostic and Statistical Manual of Mental Disorders-5 -- the standard classification of mental disorders -- removed the communication deficit from the autism definition, which made more children fall under that category. Cynical observers believe physicians and therapists are handing out the diagnosis more freely to allow access to services available only to children with autism, but that are also effective for other children.
Alycia Halladay, chief science officer for the Autism Science Foundation in New York, said she wishes there were just one answer, but there's not. While she believes the rising ASD numbers are due in part to factors like better diagnosis and a change in the definition, she does not believe that accounts for the entire rise in prevalence. As for the high numbers in New Jersey, she said the state has always had a higher prevalence of autism compared to other states. It is also one of the few states that does a good job at recording cases of autism in its educational records, meaning that children in New Jersey are more likely to be counted compared to kids in other states.
"Not every state is as good as New Jersey," she said. "That accounts for some of the difference compared to elsewhere, but we don't know if it's all of the difference in prevalence, or most of it, or what."
"What we do know is that vaccinations do not cause autism."
There is simply no defined proven reason for these increases, said Scott Badesch, outgoing president and CEO of the Autism Society of America.
"There are suggestions that it is based on better diagnosis, but there are also suggestions that the incidence of autism is in fact increasing due to reasons that have yet been determined," he said, adding, "What we do know is that vaccinations do not cause autism."
Zahorodny, the pediatrics professor, believes something is going on beyond better detection or evolving definitions.
"Changes in awareness and shifts in how children are identified or diagnosed are relevant, but they only take you so far in accounting for an increase of this magnitude," he said. "We don't know what is driving the surge in autism recorded by the ADDM Network and others."
He suggested that the increase in prevalence could be due to non-genetic environmental triggers or risk factors we do not yet know about, citing possibilities including parental age, prematurity, low birth rate, multiplicity, breech presentation, or C-section delivery. It may not be one, but rather several factors combined, he said.
"Increases in ASD prevalence have affected the whole population, so the triggers or risks must be very widely dispersed across all strata," he added.
There are studies that find new risk factors for ASD almost on a daily basis, said Idan Menashe, assistant professor in the Department of Health at Ben-Gurion University of the Negev, the fastest growing research university in Israel.
"There are plenty of studies that find new genetic variants (and new genes)," he said. In addition, various prenatal and perinatal risk factors are associated with a risk of ASD. He cited a study his university conducted last year on the relationship between C-section births and ASD, which found that exposure to general anesthesia may explain the association.
Whatever the cause, health practitioners are seeing the consequences in real time.
"People say rates are higher because of the changes in the diagnostic criteria," said Dr. Roseann Capanna-Hodge, a psychologist in Ridgefield, CT. "And they say it's easier for children to get identified. I say that's not the truth and that I've been doing this for 30 years, and that even 10 years ago, I did not see the level of autism that I do see today."
Sure, we're better at detecting autism, she added, but the detection improvements have largely occurred at the low- to mid- level part of the spectrum. The higher rates of autism are occurring at the more severe end, in her experience.
A Polarizing Theory
Among the more controversial risk factors scientists are exploring is the role environmental toxins may play in the development of autism. Some scientists, doctors and mental health experts suspect that toxins like heavy metals, pesticides, chemicals, or pollution may interrupt the way genes are expressed or the way endocrine systems function, manifesting in symptoms of autism. But others firmly resist such claims, at least until more evidence comes forth. To date, studies have been mixed and many have been more associative than causative.
"Today, scientists are still trying to figure out whether there are other environmental changes that can explain this rise, but studies of this question didn't provide any conclusive answer," said Menashe, who also serves as the scientific director of the National Autism Research Center at BGU.
"It's not everything that makes Charlie. He's just like any other kid."
That inconclusiveness has not dissuaded some doctors from taking the perspective that toxins do play a role. "Autism rates are rising because there is a mismatch between our genes and our environment," said Julia Getzelman, a pediatrician in San Francisco. "The majority of our evolution didn't include the kinds of toxic hits we are experiencing. The planet has changed drastically in just the last 75 years –- it has become more and more polluted with tens of thousands of unregulated chemicals being used by industry that are having effects on our most vulnerable."
She cites BPA, an industrial chemical that has been used since the 1960s to make certain plastics and resins. A large body of research, she says, has shown its impact on human health and the endocrine system. BPA binds to our own hormone receptors, so it may negatively impact the thyroid and brain. A study in 2015 was the first to identify a link between BPA and some children with autism, but the relationship was associative, not causative. Meanwhile, the Food and Drug Administration maintains that BPA is safe at the current levels occurring in food, based on its ongoing review of the available scientific evidence.
Michael Mooney, President of St. Louis-based Delta Genesis, a non-profit organization that treats children struggling with neurodevelopmental delays like autism, suspects a strong role for epigenetics, which refers to changes in how genes are expressed as a result of environmental influences, lifestyle behaviors, age, or disease states.
He believes some children are genetically predisposed to the disorder, and some unknown influence or combination of influences pushes them over the edge, triggering epigenetic changes that result in symptoms of autism.
For Stefania Sterling, it doesn't really matter how or why she had an autistic child. That's only one part of Charlie.
"It's not everything that makes Charlie," she said. "He's just like any other kid. He comes with happy moments. He comes with sad moments. Just like my other three kids."
Can Soil Solve the Climate Crisis?
When Rattan Lal was awarded the Japan Prize for Biological Production, Ecology in April—the Asian equivalent of a Nobel—the audience at Tokyo's National Theatre included the emperor and empress. Lal's acceptance speech, however, was down-to-earth in the most literal sense.
Carbon, in its proper place, holds landscapes and ecosystems together.
"I'd like to begin, rather unconventionally, with the conclusion of my presentation," he told the assembled dignitaries. "And the conclusion is four words: In soil we trust."
That statement could serve as the motto for a climate crisis-fighting strategy that has gained remarkable momentum over the past five years or so—and whose rise to international prominence was reflected in that glittering award ceremony. Lal, a septuagenarian professor of soil science at Ohio State University, is one of the foremost exponents of carbon farming, an approach that centers on correcting a man-made, planetary chemical imbalance.
A Solution to Several Problems at Once?
The chemical in question is carbon. Too much of it in the atmosphere (in the form of carbon dioxide, a potent greenhouse gas) is the main driver of global heating. Too little of it in the soil is the bane of farmers in many parts of the world, and a threat to our ability to feed a ballooning global population. Advocates say agriculture can mitigate both problems—by adopting techniques that keep more soil carbon from escaping skyward, and draw more atmospheric carbon down into fields and pastures.
The potential impacts go beyond slowing climate change and boosting food production. "There are so many benefits," says Lal. "Water quality, drought, flooding, biodiversity—this is a natural solution for all these problems." That's because carbon, in its proper place, holds landscapes and ecosystems together. Plants extract it from the air and convert it into sugars for energy; they also transfer it to the soil through their roots and in the process of decomposition. In the ground, carbon feeds microbes and fungi that form the basis of complex food webs. It helps soil absorb and retain water, resist erosion, and hold onto nitrogen and phosphorous—keeping those nutrients from running off into waterways and creating toxic algal blooms.
Government and private support for research into carbon-conscious agriculture is on the rise, and growing numbers of farmers are exploring such methods. How much difference these methods can make, however, remains a matter of debate. Lal sees carbon farming as a way to buy time until CO2 emissions can be brought under control. Skeptics insist that such projections are overly optimistic. Some allies, meanwhile, think Lal's vision is too timid. "Farming can actually fix the climate," says Tim LaSalle, co-founder of the Center for Regenerative Agriculture at California State University, Chico. "That should be our only focus."
Yet Can soil solve the climate crisis? may be not be the key question in assessing the promise of carbon farming, since it implies that action is worthwhile only if a solution is ensured. A more urgent line of inquiry might be: Can the climate crisis be solved without addressing soil?
A Chance Meeting Leads to the Mission of a Lifetime
Lal was among the earliest scientists to grapple with that question. Born in Pakistan, he grew up on a tiny subsistence farm in India, where his family had fled as refugees. The only one of his siblings who learned to read and write, he attended a local agricultural university, then headed to Ohio State on scholarship for his PhD. In 1982, he was working at the International Institute of Tropical Agriculture in Nigeria, trying to develop sustainable alternatives to Africa's traditional slash-and-burn farming, when a distinguished visitor dropped by: oceanographer Roger Revelle, who 25 years earlier had published the first paper warning that fossil fuel combustion could throw the climate dangerously off-kilter.
Rattan Lal, Distinguished University Professor of Soil Science at Ohio State, received the Japan Prize at a ceremony in April.
(Photo: Ken Chamberlain. CFAES.)
Lal showed Revelle the soil in his test plots—hard and reddish, like much of Africa's agricultural land. Then (as described in Kristin Ohlson's book The Soil Will Save Us), he led the visitor to the nearby forest, where the soil was dark, soft, and wriggling with earthworms. In the forest, the soil's carbon content was 2 to 3 percent; in Lal's plots, it had dwindled to 0.5 percent. When Revelle asked him where all that carbon had gone, Lal confessed he didn't know. Revelle suggested that much of it might have floated into the atmosphere, adding to the burden of greenhouse gases. "Since then," Lal told me, "I've been looking for ways to put it back."
Back at Ohio State, Lal found that the United States Department of Agriculture (USDA) and Environmental Protection Agency (EPA) were also interested in the connection between soil carbon and climate change. With a small group of other scientists, he began investigating the dimensions of the problem, and how it might be solved.
Comparing carbon in forested and cultivated soils around the globe, the researchers calculated that about 100 billion tons had vanished into the air since the dawn of agriculture 10,000 years ago. The culprits were common practices—including plowing, overgrazing, and keeping fallow fields bare—that exposed soil carbon to oxygen, transforming it into carbon dioxide. Yet the process could also be reversed, Lal and his colleagues argued. Although there was a limit to the amount of carbon that soil could hold, they theorized that it would be possible to sequester several billion tons of global CO2 emissions each year for decades before reaching maximum capacity.
Lal set up projects on five continents to explore practices that could help accomplish that goal, such as minimizing tillage, planting cover crops, and leaving residue on fields after harvest. He organized conferences, pumped out papers and books. As other researchers launched similar efforts, policymakers worldwide took notice.
But before long, recalls Colorado State University soil scientist Keith Paustian (a fellow carbon-farming pioneer, who served with Lal on the UN's International Panel on Climate Change), official attention "kind of faded away. The bigger imperative was to cut emissions." And because agriculture accounted for only about 13 percent of greenhouse gas pollution, Paustian says, the sectors that emitted the most—energy and transportation—got the bulk of funding.
A Movement on the Rise
In recent years, however, carbon farming has begun to look like an idea whose time has come. One factor is that efforts to reduce emissions haven't worked; in 2018 alone, global CO2 output rose by an estimated 2.7 percent, according to the Global Carbon Project. Last month, researchers from the Scripps Institute of Oceanography reported that atmospheric CO2—under 350 ppm when Lal began his quest—had reached 415 ppm, the highest in 3 million years. And with the world's population expected to approach 10 billion by 2050, the need for sustainable technologies to augment food production has grown increasingly pressing.
Today, carbon-conscious methods are central to the burgeoning movement known as "regenerative agriculture," which also embraces other practices aimed at improving soil health and farming in an ecologically sound (though not always strictly organic) manner. In the United States, the latest Farm Bill includes $25 million to incentivize soil-based carbon sequestration. State and local governments across the country are supporting such efforts, as are at least a dozen nonprofits. The Department of Energy's Advanced Projects Research Agency (ARPA-e) is working to develop crops and technologies aimed at increasing soil carbon accumulation by 50 percent. General Mills recently announced plans to advance regenerative farming on 1 million acres by 2030, and many smaller companies have made their own commitments.
The toughest challenge, Lal suggests, may be persuading farmers to change their ways.
Internationally, the biggest initiative is the French-led "4 per 1,000" initiative, which aims to increase the amount of carbon in the soil of farms and rangelands worldwide by 0.4 percent per year—a rate that the project's website contends would "halt the increase of CO2 (carbon dioxide) concentration in the atmosphere related to human activities."
Given the current pace of research, Lal believes that goal—which equates to sequestering 3.6 billion tons of CO2 annually, or 10 percent of global emissions—is doable. The toughest challenge, he suggests, may be persuading farmers to change their ways. Although carbon farming can reduce costs for chemical inputs such as herbicides and fertilizers, while building rich topsoil, agriculturalists tend to be a conservative lot.
And getting low-income farmers to leave crop residue on fields, instead of using it for fuel or animal feed, will require more than speeches about melting glaciers. Lal proposes a $16 per acre subsidy, totaling $64 billion for the world's 4 billion acres of cropland. "That's not a very large amount," he says, "if you're investing in the health of the planet."
Experimental Methods Attract Supporters and Skeptics
Some experts question whether enough CO2 can be stashed in the soil to prevent the rise in average global temperature from surpassing the 2º C mark—set by the 2016 Paris Agreement as the limit beyond which climate change would become catastrophic. But others insist that carbon farming's goal should be to reverse climate change, not just to put it on pause.
"That's the only way out of this predicament," says Tim LaSalle, whose Center for Regenerative Agriculture supports the use of experimental methods ranging from multi-species cover cropping to fungal-dominant compost solutions. Using such techniques, a few researchers and farmers claim to be able to transfer carbon to the soil at rates many times higher than with established practices. Although several of these methods have yet to be documented in peer-reviewed studies, LaSalle believes they point the way forward. "We can't fix the climate, or even come close to it, using Rattan's numbers," he says, referring to Lal. "If we can replicate these experiments, we can fix it."
Even scientists sympathetic to regenerative ag warn that relying on unproven techniques is risky. "Some of these claims are beyond anything we've seen in agricultural science," says Andrew McGuire, an agronomist at Washington State University. "They could be right, but extraordinary claims require extraordinary evidence."
Still, the assorted methods currently being tested—which also include amending soil with biochar (made by heating agricultural wastes with minimal oxygen), planting long-rooted perennial crops instead of short-rooted annuals, and deploying grazing animals in ways that enrich soil rather than depleting it—offer a catalogue of hope at a time when environmental despair is all too tempting.
Last October, the National Academy of Sciences, Engineering, and Medicine issued a report acknowledging that it was too late to stave off apocalyptic overheating just by reducing CO2 emissions; removing carbon from the atmosphere would be necessary as well. The document laid out several options for doing so—most of which, it cautioned, had serious limitations.
"Soil is a bridge to the future. We can't do without it."
One possibility was planting more forests. To absorb enough carbon dioxide, however, trees might have to replace areas of farmland, reducing the food supply. Another option was creating biomass plantations to fuel power plants, whose emissions would be stored underground. But land use would be a problem: "You'd need to cover an area the size of India," explains Paustian, who was a co-author of the report. Yet another alternative was direct-air capture, in which chemical processes would be used to extract CO2 from the air. The technology was still in its infancy, though—and the costs and power requirements would likely be astronomical.
The report took up agriculture-based methods on page 95. Those needed further research as well, the authors wrote, to determine which approaches would be most effective. But of all the alternatives, this one seemed the least problematic. "Soil carbon is probably what you can do first, cheapest, and with the most additional co-benefits," says Paustian. "If we can make progress in that area, it's a huge advantage."
In any case, he and other researchers agree, we have little choice but to try. "Soil is a bridge to the future," Lal says. "We can't do without it."
Meet the Shoe That Will Never End Up in a Landfill
Have you ever wondered what happens to your worn-out sneakers when you throw them away? They will likely spend the next few decades decomposing in a landfill.
"You simply take it, grind it up and make a new one. But under the surface, it's extremely technical and complex."
According to the most current government statistics, eight million tons of shoes and clothing were sent to landfills in 2015 alone. As the trashed items break down over many years, they produce toxic greenhouse gases like methane and carbon dioxide, contributing to global climate change.
The Lowdown
Sportswear manufacturer adidas was well aware of their industry's harmful environmental impact, so they set out to become part of the solution. A few years ago, they partnered with various companies to gather and reuse plastics from the ocean to make clothes and parts of shoes.
Then they wondered if they could take their vision a step further: Could they end the concept of waste entirely?
This ambition drove them to create a high-performance athletic shoe made with entirely reusable material – the new FutureCraft Loop. It's a shoe you never have to throw out.
"It's something that outwardly appears very simple," said Paul Gaudio, adidas' Global Creative Director. "You simply take it, grind it up and make a new one. I think that's super elegant and easy to understand. But under the surface, it's extremely technical and complex and it is quite literally a science project."
This project began with a group of engineers, material scientists, and designers trying to find a material that could be pliable enough to take the place of 10-12 different components normally used to make a shoe, yet durable enough to provide the support a running shoe requires. The team decided on thermoplastic polyurethane (TPU), a strong and versatile material that can be re-melted and re-molded even after it's solidified. The team worked for close to a decade on research and development.
Adidas FUTURECRAFT.LOOP
The result, Gaudio said, is an athletic shoe that doesn't compromise on quality and also won't pollute the planet. The wearer will likely notice the shoe feels different because it's welded together by heat alone.
"You feel a more direct connection [to the shoe] because you don't have the layers and glue," he explained.
Next Up
One of the next steps will be for adidas to engage with consumers to find out the best way to get them to return their used shoes for recycling so that they can, so to say, close the loop.
"We're trying to decide what that looks like," Gaudio said. "Is it a take-back program, is it a subscription mode? Do you return it at stores? So that's the next big challenge that we're working on and that's why we've started to engage people outside the brand in that process."
The FutureCraft Loop is in beta testing with a small group, but if all goes well, the shoe may be available for purchase in early 2021. The pricing hasn't been set, but Gaudio said that the goal is to make it affordable.
"If it's something that's too exclusive or unattainable," he said, "it defeats the purpose."
Open Questions
Although TPU is a completely recyclable material, the team at adidas is working to perfect the process.
"We have a passion to apply creativity and imagination to the problems of plastic in the oceans and the plastic waste."
"Each time you recycle something there is a change – a degradation and contamination," Gaudio noted. "So if I ground the whole thing up, can I make the exact same shoe again with this exact same batch of material today? No, but we can still recycle 100 percent of it. But we're working towards being able to take the knit upper and make a new knit upper."
Gaudio hopes that other companies will follow suit, although adidas is moving to develop ownership of their solutions, including the process behind making the FutureCraft Loop.
"We have a passion to apply creativity and imagination to the problems of plastic in the oceans and the plastic waste and that's what's driving us," he said.