Autism is on the rise, and recent studies have linked the disorder to everything from vaccinations to antibiotics to diet. Now, new research shows a link between autism and air pollution.
According to the study, children with autism are two to three times more likely than other children to have been exposed to car exhaust, smog, and other air pollutants during their time in utero into early childhood. The new research adds to evidence linking early-life exposure to pollutants to autism spectrum disorders (ASD), suggesting that the growing rate of ASD diagnoses are connected to rising levels of pollutants in the environment.
The study, published in the Archives of General Psychiatry, compiled information from 500 children in California. Roughly half of the children were autistic, the other half were not. Armed with the addresses of each place each child had lived during their first year of life — including the places their mothers’ lived during pregnancy — researchers determined that those with higher levels of pollutant exposure were more likely to develop autism.
The researchers, however, asserted that “their study does not definitively prove that pollution is the root cause of autism.”
“We’re not saying that air pollution causes autism. We’re saying it may be a risk factor for autism,” says Heather Volk, lead author on the new study. Volk, an assistant professor of preventive medicine at the University of Southern California, adds, “Autism is a complex disorder and it’s likely there are many factors contributing.”
She notes that genetic differences in particular may leave some children more susceptible than others to the negative effects of damaging environmental stimuli.
While new research can be beneficial in disorder diagnosis and management, for those living with autism, the overwhelming information can be exhausting.
Kelli Walker is the mother of four children. Her youngest daughter, Natalie, was diagnosed with autism just before she turned 6 years old, but Walker knew something was different about her third girl before her first birthday. “She wasn’t reaching her milestones,” Walker told The Inquisitr, “which I didn’t think too much of since she was my fourth. I thought she was just lazy.”
When Natalie — known as Nattie to her family — turned one, her parents took her to a place called Holly Ridge, where she was tested for developmental delays. She began occupational and speech therapy, and attended developmental preschool as a toddler.
“I thought she would catch up,” Walker remembers.
But Nattie didn’t catch up, and was diagnosed with autism just before her 6th birthday.
When asked what she thinks of the recent studies on the potential causes of autism, Walker notes, “I get tired of new research because ‘experts’ can be very annoying, sometimes I just don’t want to talk or think about [Nattie's autism], I just to live my life.”
“Nattie is who she is and I know my life is better for having her in it. I love her just the way she is.” Walker adds, “Although, I wish she could talk.”
While the new air pollution study suggests that kids with autism were much more likely than kids without the disorder to have been born to mothers living within 1,000 feet of a freeway, there are other pollutants that unborn babies could be exposed to in utero. Other researchers have shown that kids with autism are unusually likely to be exposed to high levels of diesel exhaust particles and metals such as mercury, calcium, and nickel.
When asked what she thinks caused Nattie’s autism, Walker recalls a conference on ASD that she attended several years ago. “Doctors flat out told us that vaccinations do cause autism for some, but not all.” Since Natalie was never vaccinated, Walker knew that couldn’t be the case with her daughter. “I believe that she was ‘predisposed’ before birth,” the mother concludes, “[I'm] not really sure what caused it, at the conference they talked about fillings [which contain mercury], which I have a lot of.”
Whether or not Nattie’s autism was caused by air pollutants or mercury fillings, the bottom line for the Walker family is that Nattie will never be like everybody else. Like other girls her age, she loves the color purple. Like girls much younger, she loves balloons and balls, and loves watching cartoons. The 14-year-old arrived at the family’s Thanksgiving celebration wearing a cute pink top and skinny jeans, looking every bit the junior high school student that she is. But instead of saying hello and joining in the family meal, Nattie does not make eye contact. She does not talk, although she does give fierce bear hugs to whomever she chooses, much to the delight of her family. When she wants something, she babbles, sometimes putting her hands over her ears when she become frustrated or overwhelmed. Later, as desserts are being served, Nattie ends up on the floor in a meltdown. Her father, John, brings her home.
Walker recalls when Nattie was in elementary school, and was trying to participate in school choir. The teacher approached Walker, noting that Natalie wasn’t participating, she wasn’t singing, she wasn’t performing. “It was so annoying. That’s like saying a person in a wheelchair wasn’t running during PE.”
“My mom was like, ‘Duh,’ ” daughter Halie, 20, recalls. “[Nattie] doesn’t talk. Why would she sing?”
Whether or not autism is caused by air pollutants, antibiotics, exposure to mercury or processed foods, or genetic disposition, the fact is that autism is rapidly on the rise. Even though the widespread belief that vaccinations cause autism has allegedly since been disproved, it is still a firm belief of some. While diagnosis is helpful in the sense that it helps “label” a child, there is no cure for autism.
“Nattie is 14. She has words once in a while, but not on cue. Sometimes she can say a phrase, but it’s hard to understand. She babbles a lot.”
When asked to define autism, Walker replies:
“My definition: Autism is a developmental disorder that affects all the important stuff, like speech and relating to others. It is diagnosed from odd behaviors such as lining up toys, being obsessed with things like shutting doors, sensitivity to light and sound, lots of screaming and meltdowns.”
While the link between air pollution and autism is yet another study on the causes on autism, researchers say that it may be one of the “best characterized environmental factors for autism.”
Do you know someone living with an ASD? What do you think of all the new research regarding the dramatic rise in autism?