Managing our waste

Waste is of two kinds:

"Why can't microbes break down plastic?" Enzymes are specific: each one breaks down only certain substances. That is why we would get no energy if we tried to eat coal! Microbes simply have no enzymes for many human-made materials such as plastics.

Non-biodegradable wastes stay in the environment for a very long time. They pollute soil and water, harm animals that eat them, and can enter food chains. Even biodegradable waste causes trouble if it is dumped in big heaps: it rots, smells and spreads disease.

Our habits matter. More and more things we use are disposable, and new kinds of packaging have made much of our waste non-biodegradable.

A story from the book: tea cups on trains. Tea used to be served in plastic glasses that were returned to the vendor. Then disposable cups came in, which seemed more hygienic, but millions were thrown away every day. Clay kulhads were suggested instead, but making them on a huge scale would use up fertile top-soil. Now paper cups are used. The lesson: an easy answer can have hidden costs, so think it through.

What you can do:

• segregate waste at home: wet (biodegradable) and dry;
• compost the wet waste;
• reduce, reuse and recycle;
• carry a cloth bag and avoid disposable items;
• switch off lights and fans you are not using.

Try the book's activity: find out how much waste your home makes in a day, how much of it is biodegradable, and what your colony or town does with it.