Smoke from cigarettes is now listed along with neurotoxins such as pesticides as contributing factors to attention deficit hyperactivity disorder symptoms.

You can now place cigarettes alongside pesticides when it comes to attention deficit hyperactivity disorder (ADHD).

A new study shows that exposure to secondhand smoke of as little as one hour a day increases a child’s risk of ADHD dramatically — up to triple the risk compared to children who are not exposed.

Neurotoxins — like lead, mercury, and organophosphate pesticides (the most common in the United States) — have been linked to lower IQ, autism spectrum disorders, and ADHD.

Pesticides and other common household chemicals, even something as seemingly benign as fluoride in toothpaste, are identified as neurotoxins at certain levels of exposure. They too have a proven link to ADHD.

In fact, scientists say exposure to harmful chemicals could explain, at least in part, the increase in both ADHD and autism diagnoses, especially considering children are more susceptible to greater negative neurological effects than adults.

Now secondhand cigarette smoke, which contains more than 70,000 chemicals according to the Centers for Disease Control and Prevention (CDC), can be added to that growing list of environmental factors that can potentially increase children’s risk of ADHD.

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Any neurotoxins ingested by an expectant mother have the potential to damage the developing nervous system of the baby she’s carrying.

Pregnant women, in fact, are urged to avoid all secondhand smoke, a task the CDC says is easier than ever before. The exposure of nonsmokers to secondhand smoke has dropped from 89 percent two decades ago to slightly more than 25 percent today.

Adults can avoid additional neurotoxins by eating strictly organic foods and dodging as many other toxins as possible, such as the chemical transfer to food cooked in nonstick pans and the potential for high levels of mercury in fish.

Children’s nervous systems are still developing rapidly up to age 2, so even low exposure to neurotoxins can cause lasting, significant brain damage. Approximately 40 percent of children ages 3 to 11 are exposed to secondhand smoke. It’s recommended that kids not be exposed to any secondhand smoke while their nervous systems are developing.

In addition, officials recommend parents monitor additional fluoride (recommended use of toothpaste with fluoride is considered safe), avoid beverages from plastic containers and metal cans, and cook family meals on pans without nonstick coatings to limit dangerous exposures.

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What can we do to limit the effects of environmental toxins for children who already have ADHD?

First, scientists say do not smoke around your child and don’t let anyone else either. While the child might already have ADHD, cognitive and behavioral symptoms can worsen with continued chemical exposure.

In his book, “Health-Defense: How to Stay Vibrantly Healthy in a Toxic World,” author Bill Gottlieb and the editors of Prevention magazine offer several ways to defend children against toxic threats.

Among them are having your home tested for lead and then having it professionally removed. In addition, buy low-mercury fish, like wild-caught Alaskan salmon, and trim fatty parts of meat. If you can, feed your family organic food, especially snap beans, tomatoes, and watermelon.

They also say to avoid canned foods and beverages and number 7 plastics as well as cookware with nonstick coating.

The authors also recommend considering an air purifier for your home as well as opting for natural flooring, not carpeting.

Finally, they urge parents to avoid vinyl, buy fresh or frozen food whenever possible, and skip dry cleaning your clothes.

When researching alternative treatments for her son after his ADHD diagnosis at age 10, Jennifer Campbell, a North Carolina mom, felt she had to drastically overhaul her son’s diet as well as their home environment.

“I decided we had to eat an organic diet, free of artificial dyes and chemicals,” Campbell told Healthline. “I also eliminated wheat, barley, and dairy, which was hard since my son’s favorite food was cheese.”

In addition, she changed household chemical products — cleaners, shampoo, and toothpaste — to all-natural versions. She noticed an improvement in her son’s fidgeting and attention within four weeks. She says he’s still doing well on this diet three years later.

Experts also urge parents to create an appropriate home environment for kids with ADHD for better symptom control.

“Some kids with ADHD are described by their parents as ‘over-sensitive,’” say Elaine Taylor-Klaus and Diane Dempster, parenting coaches and co-founders of “A lot of clutter in the home, or too much yelling, can make some kids with ADHD feel particularly stressed out. When they are already having a difficult time processing or making sense of basic information, these added stressors can push them beyond their limits.”

Be cognizant of sensory input that may be stirring anxiety or frustration in a child with ADHD as well. Taylor-Klaus and Dempster recommend a home environment with clearly established expectations, consistent routines, and limited visual clutter.

“It also helps for them to have some choice in the matter, perhaps two different places that are approved to do homework, so they don’t get bored,” advise Taylor-Klaus and Dempster.

A self-described “veteran” parent of a son with ADHD, Penny Williams is an award-winning blogger and author of the Amazon best seller, “Boy Without Instructions: Surviving the Learning Curve of Parenting a Child with ADHD.” Her second book, “What to Expect When You’re Not Expecting ADHD,” is now available.

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