When we hear about responsible sourcing in the context of sustainable packaging, it’s usually an advocacy for using either renewable resources from well-managed sources, or non-renewable resources from the recycling stream instead of virgin sources. This broad guidance certainly covers the major considerations of responsible sourcing, but an upcoming U.S. Securities and Exchange Commission vote led me to believe that there are greater dimensions for us to consider.
The vote applies to a provision of the 2010 Dodd-Frank Act that would require companies to disclose their usage of conflict minerals from the Democratic Republic of Congo and the surrounding region. There are four basic minerals of concern: gold, wolframite (source of tungsten), columbite-tantalie (source of the element tantalum), and cassiterite, which is the most important source of tin. Most of the scrutiny around these minerals occurs with makers of electronics, and at first glance there’s not much of a connection to packaging. My thinking was “definitely no gold in packaging, can’t imagine there’s any tungsten, no clue what tantalum is, and tin might only show up in small amounts in tin cans (which are made almost entirely from steel, in case you didn’t know).” Yet, life cycle inventory data always reveals a host of materials that one wouldn’t normally associate with the major packaging materials, and sure enough, there’s a measurable amount of tin used to make most kinds of packaging.
Organic compounds containing tin can be used as catalysts, stabilizers, or polymerization aids to make plastics. Tin is an alloying element in aluminum. Glass containers have a coating of a tin-bearing compound. And yes, tin cans are indeed coated with tin. On a kilogram-by-kilogram basis, it’s actually glass containers that use the most tin. Second place? Recycled folding boxboard. Of all the materials, I have no clue how tin factors into making recycled folding boxboard – if you know, fill me in, please.
Even so, the amount of tin used is relatively tiny. Using the example of glass containers, a rough calculation tells me that about 52 kilograms of tin were used in all the container glass produced in 2010 – that’s 52 kilograms of tin to make 8.5 billion kilograms of container glass. 52 kilograms of tin? That’s not much. To put that in perspective, Wikipedia tells us that almost 300 million kilograms of tin were produced in 2006.
Wikipedia also tells us that somewhere around 80-90% of the world’s tin is produced in China and Indonesia. So what are the chances that the tin used in packaging comes from the Democratic Republic of Congo, where it is alleged that the sale of minerals goes to funding the conflict there? Probably pretty low. Nonetheless, it seems quite plausible that somewhere in someone’s packaging supply chain, there’s at least a miniscule occurrence of conflict tin. Addressing our usage of tin in packaging probably ought not to be high on our list of ways to make packaging more sustainable, but it’s something to keep in mind.
My takeaway is this: there is an absolute plethora of materials that go into making packaging. If we want packaging to be truly sustainable, we have to examine every input. We can’t overgeneralize packaging and improve our usage of only the biggest raw materials. Things like tin, however small our usage is, can’t be ignored, especially when lives may hinge on it.
Be sure to check out this great article in Triple Pundit if you’d like to learn more about conflict minerals.