Our government won’t protect us from these harmful chemicals, so we have to protect ourselves.

What keeps you up at night? Sick kids, restless pets, the latest tragedy on the evening news, politics, wars, earthquakes, hurricanes, fires, money troubles, job stress, and family health and wellbeing? There is no shortage of concerns that make us all toss and turn.

But what keeps the chemical industry up at night? A couple of decades ago a senior Shell executive was asked this very question. The answer? Endocrine disruption.

If you can even pronounce “endocrine disruption,” you’re doing well. What is it? Why should we care? And why is it keeping chemical bigshots up at night?

The endocrine system is the system of glands, hormones and hormone targets that is responsible for almost everything our bodies do. Hormones are chemical messengers that control blood sugar, infant and child development, sexual function, growth, energy production and much more. Without them, we would not be ourselves. Hormones are particularly impressive because tiny amounts of them, so small they’re difficult even to comprehend, have profound effects on our health and well-being.

In the last 30 years, we’ve learned that synthetic chemicals, widely used in industry and agriculture, can disrupt the way that this finely tuned system works. We call these chemicals—including compounds made from lead, mercury and arsenic, DDT, BPA and phthalates—endocrine disrupting chemicals (EDCs).

These chemicals are known to cause obesity, diabetes, heart disease, reduced fertility, premature birth, reduced sperm quality and cancer. Exposures before birth, during childhood and during the teenage years are especially important because of the rapid growth and development that occurs during those periods. Now new research indicates that some EDCs cause problems that are passed along for generations.