Taking public transportation to the office is only the first step in leading an eco-conscious work life. “True Green @ Work: 100 Ways You Can Make the Environment Your Business,” by Kim McKay and Jenny Bonnin (National Geographic, $19.95), offers many other tips, whatever your corporate culture. Here are five of our favorite ideas from the book:

¢ Use your own mug for coffee, instead of adding to the 1.9 million tons of disposable cups tossed in the trash each year.

¢ Persuade your boss to relax the rules on business attire. It saves cleaning costs (plus energy). Lighter clothes also permit the office thermostat to be set higher in warm weather.

¢ Ask building managers to turn off lights at night or install motion-activated sensors. Lighting accounts for 20 percent of greenhouse gas emissions from commercial buildings.

¢ Start a collection of old cellphones with your colleagues. Organizations such as ReCellular.com will refurbish, reuse and recycle retired handsets.

¢ Keep an indoor plant at your workstation. Plants act as natural air filters and can absorb some airborne pollutants.