Muntasir Mamun and Mohammad Ujjal are riding across the United States on a bicycle built for two. As they pedal in sync from Seattle to New York, they’re not only gazing at our purple mountains’ majesty and amber waves of grain. They’re also keeping their eyes peeled for plastic soda bottles, glass beer bottles, and Styrofoam cups.

These self-dubbed “trashmaniacs” are collecting and recording every piece of trash they find on their 5,000-mile trip. Their mission? To make us more aware of how the waste that we generate here can have a profound effect in places very far away.

I love what these guys are doing—and the offbeat, creative way they’re doing it. So I’ve been thinking of how to use Minitab to help them spread their message.

Using a Pareto chart to track litter

Mamun and Ujjal are from Bangladesh, which has a dense population living in the delta region near the sea coast. At those low elevations, even a slight rise in sea levels due to climate change would be devastating for millions of its people.

So their message is simple: Let’s be more efficient and not waste what we produce. By reusing materials and consuming more thoughtfully, we can reduce the energy and environmental costs associated with overproducing products that are too quickly discarded as waste.

“In Bangladesh no plastic bag or bottle is ever wasted,” they write. “But a few wasted plastic bottles thousands of miles away is still bad news to a place that is among the most vulnerable in the world.”

After more than a month on the road, Mamun and Ujjal just crossed the Iowa-Illinois border. The Minitab Pareto chart below (Stat > Quality Tools > Pareto Chart) shows the most common types of trash they’ve collected.

So far, the “vital few” roadside defects are mainly discarded beverage containers: plastic bottles, aluminum cans, and glass bottles.

Using time series plots to track waste disposal

Have we made any progress in recycling and waste disposal during the last 50 years? To find out, I obtained historical data on municipal waste from the U.S. Environmental Protection Agency (EPA) and used it to create time series plots in Minitab with multiple variables (Graph > Time Series Plot > Multiple).

The plot shows that we’ve made great progress in recycling paper. Unfortunately, after a promising start, our rate of recycling aluminum has dropped during the last two decades.

Recycling rates for plastic and glass show an upward trend—and that’s good news. However, we recycle only about 25 percent of the glass and 8 percent of the plastic that we generate.

Are our rates of recycling increasing fast enough? The plot below shows the millions of tons of municipal waste that are still left over after recycling.

On the positive side, the amount of discarded paper in the United States has dropped dramatically—almost 30 million tons during the last decade alone. So we really can change our ways! Hopefully, this trend is quadratic (i.e., an inverted U) and will drop even more by 2020.

On the negative side, the plot corroborates what the trashmaniacs are finding on the road: too much plastic waste.

Unless we change our behavior, discarded plastics could continue to follow the steadily increasing linear trend shown on the plot and reach more than 30 million tons annually by 2020.

A pie chart of discarded plastics

Now that we know plastic is a major contributor to waste, let’s use a Minitab pie chart to see what types of plastic make up the 28 million tons we discarded in 2010.

(Choose Graph > Pie Chart. Click Labels and adjust options to display the labels on the outside of the pie.)

The chart shows that plastic bags, sacks, wraps, and other plastic packaging make up more than 60 percent of our plastic waste. About 16 percent (2 million tons) of the plastic that we discard annually contains polyethylene terephthalate (PET), a thermoplastic polymer used in soft drink bottles and plastic jars. (I’ll let you Google that and draw your own conclusions.)

Simple visuals = powerful messages = real change

Sometimes, you don’t need a lot of complex calculations to get a point across. These simple Minitab graphs—and the honest, direct message of the trashmaniacs—have convinced me that I need to make more of an effort. So here are a couple of things I’m going to start doing from now on.

Avoid using plastic grocery bags. A few years ago, Minitab gave each employee an eco-friendly reusable grocery bag. It’s still in my car—but I haven’t used it once, sad to say. No excuses anymore!

Choose products with minimal packaging. I’m going to make a conscious and deliberate effort to purchase items at the store that are not mummy-wrapped in wasteful packaging.

Skeptics might say that my small changes won’t make much of a dent in the millions of tons of plastic that we discard each year. But as Mamun and Ujjal show us, as individuals we really can make a difference.

We all need to get on a bike together—one built for about 9 billion people.