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

From the right to know and the duty to inquire flows the obligation to act.

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.

The study of how substances alter gene expression is part of the field of epigenetics. Some chemical exposures appear to turn on and turn off genes in ways that disregulate cell growth and predispose for cancer. From this perspective, our genes are less the command-and-control masters of our cells and more like the keys of piano, with the environment as the hands of the pianist.

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

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.

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.