When humans discovered fire, it was progress. More discoveries followed, and now progress is symbolized by 100,000 industrial chemicals developed in the past 70–80 years, compounds that have found their way into the environment and into the bodies of living organisms, including humans. Blood tests reveal that people harbor numerous toxic chemicals, including heavy metals, dioxins, fluorocarbons, and even DDT. Our bodies, having become accustomed to exposure to contaminants, resist them in small amounts. But the basic principle of toxicology is that it is the dose that makes a chemical poisonous and, as toxin levels increase, problems can result.

Pollutants are everywhere – in plastics, toys, nonstick cookware, household cleaners, and as preservatives in a variety of products. Much of our food is contaminated. Meat may contain several hormones, and pesticides are frequently found on vegetables and fruits. Many toxins enter the water and travel up the food chain to humans.

Environmental poisons can affect several body systems. Some alter gene expression at low levels; others block hormone receptors. Allergies and attention deficit disorders are linked to contaminant exposure. Reproductive anomalies, changes in sperm quality, and diminished fertility have been observed in many animals and even in humans, sometimes resulting from prenatal pesticide exposure.

This 88-minute program is conveniently divided into 25 short scenes. It has subtitles that can be turned on or off and includes 45 minutes of interviews with scientists and environmentalists. (The DVD also contains a 52-minute version for use if time is an issue.) The format holds the viewer’s attention with frequent changes of approach, beautiful photography, and challenging dialogue. Loaded with thought-provoking information, it’s a powerful foundation for a unit on environmental toxins in a biology or environmental science class. Each scene, or group of scenes, could be the basis for reflection and discussion, with further reinforcement using activities such as debates, reports, posters, symposia, and creative arts projects. It could also be a challenge to action for groups desiring to take it further.

The DVD’s “toxic buffet” is an attention-getter in which people on a busy city street are offered a variety of attractive, appetizing foods, typical of those that contain environmental contamination. Passers-by have lots of questions, but there are no easy answers. Nature is warning us, though. Amphibian and bee populations are disappearing; plants and animals are threatened with extinction; rivers are dying. Humans continue to introduce chemicals into the environment without realizing their health effects. The ominous truth is that we don’t know when we will exceed the breaking point.

Though the program was filmed primarily in Canada, environmental contaminants know no geographic boundaries. This compelling presentation is a hard-hitting wake-up call, appropriate for high school, college, or adult viewing. It could be the Silent Spring for the current generation.