We can change our thinking. Rather than viewing the chemical adulteration of our environment and our bodies as the inevitable practice of convenience and progress, we can decide that cancer is inconvenient and toxic pollution archaic and primitive. We can start seeing the creation of carcinogens as the result of outmoded technologies. We can demand green engineering and green chemistry. We can let our systems of industry and agriculture know that they are suffering from a design flaw.

I'm beginning to perceive motherhood as a long, slow letting go, of which birth is just the first step.

In the world outside this glass room, songbirds are feeding and resting in the trees. Some will take off tonight and not land until they reach Venezuela. Sandpipers, plovers, and broad-winged hawks have already left for Patagonia and Panama. Bats are headed for caves in Kentucky and Tennessee. Out in the Atlantic, humpback whales pass by on their way to the Caribbean. Even now, Canada geese are honking toward us from Quebec. It is a good day for the beginnings of journeys.Every time I look at you, I think, Now I cannot die.

We can decide that the presence of cancer-causing substances in our air, water, and food is too expensive. A 2009 study, for example, has found that coal miners in Appalachia costs the region five times more in premature deaths, including from cancer, than it provides to the region in jobs, taxes, and economic benefits. In California, the production and use of hazardous chemicals cost the state $2.6 billion in 2004 alone in lost wages and health-care expenses to treat workers and children with pollution-linked diseases.

Besides, the sense of safety offered by bottled water is a mirage. It turns out that breathing, not drinking, constitutes our main route of exposure to volatile pollutants in tap water, such as solvents, pesticides, and byproducts of water chlorination. As soon as the toilet is flushed or the faucet turned on-or the bathtub, the shower, the humidifier, the washing machine-these contaminants leave the water and enter the air. A recent study shows that the most efficient way of exposing yourself to chemical contaminants in tap water is to turn on a dishwasher.

Drink a bottle of French water and then step into the shower for ten minutes and you've just received the exposure equivalent of drinking a half gallon of tap water. We enjoy the most intimate of relationships with our public drinking water, whether we want to or not.

Between the late 1950s and the late 1980s, more than 750 million tons of chemical wastes were discarded.