Bad Chemistry

Substances in our furniture, fruit and skin creams are changing the basic physiology of children. What can we do to protect them?

imagine a playground in new york city in the early 1960s. A few dozen children between the ages of 4 and 12 are running around on the concrete, climbing iron monkey bars, taking turns on the steel-encased swings and riding a planked seesaw. The same playground today looks much different. Kids play on artificial turf and a spongy surface made from recycled tires. Gone are the metal swings, the seesaw and the monkey bars; instead, they wander through a maze of stairs and slides and use what looks like equipment you’d find in a gym.

The children themselves have also changed. They’re bigger and heavier. A 5-foot-1-inch boy might look 12 though he’s 9. A girl with the breasts and hips of a 14-year-old is actually 8. The adults, too, are different: Almost half of them are overweight, and a good number border on obesity.

If I were to examine both sets of children, I might find many other differences. One or two kids on the playground might have a diagnosis of autism spectrum disorder, and several would show significant learning disabilities. Today, children suffer from increasing numbers of diabetes, high blood cholesterol and high blood pressure cases—conditions that used to affect only the elderly and infirm. More than 13 percent of boys and 5 percent of girls are diagnosed with attention deficit hyperactivity disorder. If I could look into the futures of these playground kids, many of the boys would grow up to have low sperm counts and the girls might develop reproductive issues, including endometriosis and infertility.

In only one or two generations, the basic physiology of kids has been altered. What happened? Many of the “lifestyle diseases,” such as diabetes and high blood pressure, have been attributed to sedentary living, sugar-laden foods, lack of exercise and poor access to fresh fruits and vegetables. But that may not be the whole story. Our ability to sequence the DNA of the human genome has allowed scientists to trace the potential origins of many of these diseases to factors in the environment, such as the presence of chemicals that, through exposure, can modify the expression of genes, leading to diseases and dysfunctions.

In the past few decades, we have constructed a world of industrial chemicals that are present in our soil, farms and food supply; our cosmetics, hygiene products and household furniture; and our gardens, lawns, fields, recreational parks and other outdoor spaces. Many of the chemicals we are exposed to on a daily basis are “endocrine disruptors,” which means they disturb the proper functioning of hormones in the body by mimicking the activity of a natural hormone or suppressing the activity of a natural hormone. This can lead to abnormalities in cells and tissues in the brain and other organs.

At first, it was thought that these chemicals had to persist in the body to cause harm, like a viral or bacterial infection. Now we realize that though the human body excretes these chemicals within a few days, they leave lasting effects on all of us—especially babies and young children, whose organs are

just developing.

In recent years, regulators have taken steps to reduce the presence of some harmful chemicals in our lives. In 2016, President Barack Obama signed an update to the Toxic Substances Control Act to improve the review of chemicals for safety. However, the Environmental Protection Agency is unlikely to have sufficient funding or political support to evaluate the thousands of chemicals in circulation that lack sufficient testing data. In the first two years of the Trump administration, we’ve seen efforts to undermine the newly revised law. In any case, thousands of chemicals are out there, and most have yet to be studied, let alone regulated. It’s not likely that they will be removed from our environment anytime soon.

Although much is still unknown, scientists have been able to study in detail the health effects of four main categories of chemicals in widespread use: pesticides, plasticizer chemicals, bisphenols and flame retardants. While we’re waiting for scientists and regulators to catch up, there are steps we can take as individuals to help reduce our exposure. Below, I offer some interventions that we can all practice, with this note of caution: Some similar interventions studied in the lab don’t always achieve the expected results. The world of chemicals and human development is complicated and poorly understood.

PESTICIDES

The active ingredient in many pesticides, a class of compound known as organophosphates, was first developed as human nerve gas agents during World War II. The chemicals impaired the proper functioning of the brain by blocking the breakdown of acetylcholine, a neurotransmitter that neurons use to communicate with one another. Organophosphates were subsequently recognized to be effective at killing insects via the same mechanism at much lower concentrations. Regulation in the U.S. has reduced exposure from organophosphates, compared with the early days of pesticides; the Food Quality Protection Act requires safety precautions to protect children from pesticides in food. Levels of organophosphate breakdown products in the urine of children and pregnant women are lower in the U.S. than in Europe.

Eating organic foods has been documented to reduce levels of organophosphate breakdown products in the urine. Certain vegetables and fruits— strawberries, grapes and cherries, to name a few—are known to deliver the highest levels of pesticides to people’s bodies. Even careful washing gets off only so much of the pesticide residue. For potatoes and nectarines, which also belong in this category, removing the skin or rind is an option. Asparagus, cauliflower and some other vegetables have been found to have low levels of pesticide residue.

PLASTICIZERS

To make plastics soft, manufacturers use a type of chemical called phthalates. They crop up in food packaging and are used to enhance scents and smells of personal care products such as lotions and cosmetics. Phthalates are possible contributors to obesity. Some of the phthalates used in lotions and cosmetics act to block the effects of the male sex hormone testosterone, while others used in food packaging can mimic estrogen. In laboratory studies, phthalates have been found to influence the expression of genes that govern the production of thyroid-stimulating hormone. Because these chemicals leave no specific fingerprint in the body, it is difficult to know what effect they have on the brains of developing young children.

One easy way to reduce exposure to phthalates is to avoid canned foods in favor of foods that are fresh or come in glass containers. Here are other measures that reduce consumption of phthalates in food:

• Don’t reuse disposal containers .

In addition to the risk of endocrinedisrupting chemicals, reusing plastic containers raises the chance of bacterial contamination.

• Avoid Number 3 plastics. Containers with a recycling number of 3 on the bottom pose a risk of contamination with phthalates.

• No plastic in the microwave . <oušre inviting plastics to melt at a microscopic level and travel into food. 7here is no such thing as microwave-safe plastic.

• No plastic in the dishwasher. Wash containers by hand with mild soap and water instead. Harsh detergents etch the plastic and increase absorption into liquids and foods.

• Throw away etched containers. When plastic is etched, it increases the odds that phthalates will leach into food.

BISPHENOL A

This synthetic chemical, also known as BPA, is used in the lining of food and beverage cans, even though it has been banned from baby bottles and sippy cups. BPA is best known as a

Exposure to chemicals in the environment can modify the expression of genes, studies show, leading to diseases and dysfunctions.