Ancient Pollution

In my last post, I wrote about the Hebrew University campus where I am staying this summer. I didn’t really get into why I am here, though. Well, I have one word for you… pollution! Today, pollution is an issue that is as relevant as ever, wherever you are in the world. But many people may not think about the impact ancient pollution had on societies of the past. Or that in some cases, ancient pollution is still harmful to humans, even after 3000 years!

Consider this – between 1000 BCE and 300 CE, the area of southern Jordan where I work was a main source of copper for much of the Middle East. Over the centuries, archaeologists estimate that thousands and thousands of tons of copper were smelted and shipped out to other locations in the eastern Mediterranean. Ancient smelting technology easily would have produced five to ten times as much waste as copper. We’re talking about some serious trash here.

In each region of the world, the kind of pollution that can result from smelting depends on a few things. For example, what elements occur naturally in the ores, and are released when smelted? What techniques were used to smelt the ores? Sometimes smelting requires the addition of toxic substances to extract the metals from the host rock, while other times it may only require heating (though at really high temperatures!). Where I work, the most common byproducts are copper (of course) and lead, but arsenic and other toxic substances may also be present.

The big question looming over this research is a basic issue of our human heritage: why is there pollution? Of course copper smelting produces some highly undesirable substances. But why does it spread beyond the confines of a copper smelting factory, to say, nearby agricultural fields? Now, color me crazy, but I really don’t think it’s fair to assume that ancient societies were naturally destructive. Or that they were entirely unaware of the damaging effects of pollution.

At an even more general level, this research is about a fundamental aspect of human nature. Is it natural for human societies to destroy the environment? Is environmental degradation – whether erosion, pollution, deforestation, or animal extinctions – an unavoidable consequence of being human, of living in cities, or of development?

Often people approach these kinds of questions by looking to the past. How has the situation changed over the course of human civilization? One way of looking at it is to say that things are only getting worse, that human civilization is contributing more and more to the destruction of our world. Another way to answer the question is to say that ancient humans were oblivious to the consequences of their actions, and thus were equally or more destructive than now. I don’t think either of these answers is sufficient.

During the next two months I won’t be able to even come close to answering these broad questions. Even answering some of these questions for southern Jordan specifically would take years and years of research (as one of my recent (negative) grant proposal reviewers pointed out). But, by looking at how the environment was polluted, when it occurred, and under what conditions, we’ll begin to see the bigger picture.