Global Pollution's Local Effects

IT'S been aptly said that pollution is a local problem with global implications. What's less well recognized is that those global implications can involve serious local consequences far from the original source of the pollution. Winds can carry toxic chemicals evaporating from weed killers used in one community and deposit them in rivers, streams, and lakes a continent away. Dioxins, PCBs, and other synthetic industrial chemicals can - and do - move through the air to the ends of the Earth.

Reviewing this neglected environmental challenge in the American Chemical Society journal Environmental Science & Technology, Curtis C. Travis, director of the Office of Risk Analysis at the Oak Ridge National Laboratory, and his colleague Sheri T. Hester note that "Arctic inhabitants are experiencing near-toxic levels of PCB exposure." They explain that this is "primarily ... a result of consumption of contaminated fish and aquatic mammals." In other words, pollutants are concentrated as they move thro u

gh the food chain.

This arctic pollution does not represent the dirty "fingerprints" of on-the-spot explorers or local inhabitants. It is a manifestation of the fact that the waste of the entire world moves globally, usually in highly diluted form, to be deposited and concentrated where one may least expect it.

The Oak Ridge analysts note that some chemicals identified as hazardous by the United States Environmental Protection Agency literally "are everywhere." "Virtually every man, woman, and child in the world is exposed to these compounds ... [which] have been measured in practically all media - air, soil, meat, milk, fish, vegetation, and human biological samples," they say.

The analysts further note that "little attention has been given to the global implications of human production and use of synthetic chemicals." Yet they now perceive that "a consensus is emerging that even trace levels of environmental contamination can have potentially devastating environmental consequences."

This puts pollution control in a new perspective. Communities cannot fully protect themselves by cleaning up superfund sites, regulating factory emissions, or controlling other local pollution sources - important though this control may be. Chemicals moving through the air from sources half a world away can also be a threat.

The only truly effective way to protect the planetary environment as a whole - and hence one's own community in particular - is to reduce or eliminate the production and use of polluting chemicals globally. The Oak Ridge analysts are not the first environmental scientists to reach this conclusion. However their review shows that the situation has become serious enough that environmental planners can no longer ignore it.

Persuading the world to change its industrial and agricultural practices to curb global pollution seems a daunting challenge. It calls for major technological and economic adjustments. It also calls for a change in mind-sets. For example, using fewer pesticides on farms or forgoing chemical lawn care - two major sources of global chemical pollution - are choices that can be made now. The overriding need is to put the emphasis in national environmental policy where it should be - on recycling, on reducin g

chemical waste, and on forgoing use of polluting chemicals wherever possible.