The opening of the Panama
Canal in 1913 transformed ocean-shipping and the availability of
internationally-traded goods, shortened travel time between the Pacific and
Atlantic oceans, increased ship tonnage, and sparked the growth of port
authorities on both the Atlantic and Pacific coasts of the Panama Canal.
Historically, the United States was number one and China was number two in tons
of cargo that pass through the canal annually in the high stakes game of import
and export markets. Prior to the construction of the Panama Canal, the most
efficient way to cross the 82-kilometer isthmus, between the Port of Panama
City on the Pacific and the Port of Colon on the Atlantic, was by mule trails
through tropical forests and river transportation. Since the construction of
the Panama Canal through tropical forests in the 1910s, pesticides have been
essential for managing mosquitoes as well as controlling wetland vegetation
that blocked lakes, rivers and the canal. The primary objective of this
research study is to document the long-term environmental impacts of pesticide
and herbicide use in the Panama Canal Zone. Many of these chemicals, including
2, 4,-D, 2, 4, 5-T and DDT, have a long half-life under water and some, like
arsenic (As), have no half-life. Pesticides and chemicals flowed into Lake
Gatun via surface runoff either in solution or attached to the sediment during
the rainy season. The by-product 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is
an unanticipated contaminant created during the manufacture of the herbicide
2,4,5-T. TCDD can bio-accumulate in fish and birds and enter into the human
food supply. The extent of the current chemical and pesticide contamination on
former U.S. military base grounds and in Lake Gatun is unknown. Systematic soil
sampling of current and former military bases, chemical disposal sites and Lake
Gatun or the Panama Canal sediments is needed to determine if mitigation is
necessary.
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