There’s a battle brewing in freight transportation over a small yet vital component of the nation’s freight system – the lowly pallet. This commonly-overlooked device is the foundation of goods movement; it is the primary component of today’s containerized system. In the United States our freight is shipped on an estimated 1.4 billion pallets in active circulation. Of these, 93% are constructed from wood, with the nearly all the rest molded from plastic.
Needless to say, a large industry has evolved around pallet construction, distribution, maintenance, and recycling. As of the year 2000 there were over 2,700 pallet manufacturers in the US, most of whom also recover and recycle used pallets. In that year the market for new and “pre-owned” pallets topped 650 million units. Given these numbers, it’s no surprise that the pallet industry would cast a long shadow of environmental impacts; nor is it a surprise that industry groups would battle over who is to blame.
These impacts were in the spotlight last November when the consumer products firm Johnson & Johnson began to recall shipments of its pain reliever Tylenol. The company was reacting to consumer complaints of nausea, vomiting, and diarrhea surrounding the product. The recall, recently expanded to Rolaids, Benadryl, and a dozen other over-the-counter brands, has been blamed on chemical residues transferred from the wooden pallets used in the shipment. The chemical, methyl bromide (phased out in the US but still widely used overseas) was applied as a pesticide to kill any insects living in the wooden pallets, conforming with requirements of the UN International Plant Protection Convention. Excess fumigant remained on the pallets and tainted the goods they carried, and ultimately sickened the consumer. It’s still not clear why the chemicals were passed on in this case but not in other situations with fumigated pallets.
This debacle has become a sawhorse for industry groups seeking to win public-relations points. The Reusable Container & Pallet Association calls attention to the recall as another example of how plastic pallets are more sanitary and less polluting than wooden pallets. These claims have been rebuked by the National Wooden Pallet and Container Association (slogan: “Pallets Move the World”), who point out that plastic pallets have their own contaminants, including the soon-to-be-banned brominated flame-retardant DECA. Each side claims the green mantle when comparing the two products side by side.
It’s undeniable that wooden pallets have a different environmental footprint than plastic pallets; but it’s less clear which footprint is smaller. Most of the environmental claims revolve around lifecycle sustainability of each product. Unfortunately, much like the “paper vs. plastic” grocery bag controversy, much of the LCA analysis depends on specifics of where and how the product is produced, recycled, and disposed, which will vary from company to company. Instead, we’ll focus on a problem we can solve (or at least characterize), the fuel economy implications of the lighter plastic pallets over their wooden competition.
While it’s true that plastic pallets weigh half as much as their competition, the fact that pallets account for such a small percentage of total freight ton-miles means that any savings due from an individual pallet will be very small. However, the sheer size of the freight industry means that even small changes have large aggregate impacts. By shaving 30 lbs. off of the traditional pallet weight, a plastic pallet plastic could save a half-pint of diesel every year, or two gallons of diesel (or approx $7) over its lifetime. In aggregate however, the fuel savings are much larger. If the market share of plastic pallets were to increase by 1%, the freight industry would save a million gallons of diesel every year, equivalent to eleven thousand tons of CO2, or taking two thousand cars off the road.
So while the impact of a single pallet may be small, the benefits of large-scale changes can add up. This is one reason why companies such as Wal-Mart, which have greater vertical influence over their supply chain, are pushing suppliers to adopt greener practices including pallet sourcing and recycling. To the extent that environmental benefits align with economic benefits, the lowly pallet may make a great contribution to a cleaner transportation system.
