By Kathryn Bender, Star-Bulletin
Sewage spills from a cracked pipe under Hy-Pac Self Storage,
contaminating Keehi Lagoon.
While pollution levels have fallen at more than 100 sites along the nation's coastline, the study noted that 21 sites had high and increasing concentrations of chemicals, and called for them to get special attention from cleanup experts. The upward trends, the ocean agency report said, "should be interpreted as indicating that ongoing human activity is increasing chemical contamination."
Numerous shores in many areas of the United States are closed to swimming and shellfishing and some are undergoing expensive cleanup programs.
In addition to Keehi Lagoon, the sites of concern included the Shark River in New Jersey, Naples Bay in Florida, Biloxi Bay in Mississippi, and Lovers Point in Pacific Grove, Calif.
The study monitored 14 elements and compounds. The trace elements under study were arsenic, cadmium, copper, mercury, nickel, lead, selenium and zinc, all of which can be harmful to humans and sea life in high concentrations.
The organic compounds under study were DDT, chlordane, dieldrin (all pesticides), butyltin (a paint additive), PCB (an electrical industry chemical) and PAH (a widespread byproduct of industrial and oil pollution). In high concentrations, many of these compounds can cause cancer and genetic mutations or can interfere with reproduction.
Thomas P. O'Connor of the National Oceanic and Atmospheric Administration, the head of the study, said in an interview that many of the 14 chemicals had been outlawed or restricted in their use or discharge into waterways. In other cases, he said, the declines appeared to be caused by voluntary cutbacks or economic changes that reduced industrial reliance on the dangerous chemicals.
"There are lots of decreases and some increases," he said, adding that the declines were comforting but not wholly unexpected, given the increasing efforts in recent years to stem coastal pollution.
The study monitored mussels and oysters at 154 sites from coast to coast and found 217 decreases in chemicals and 41 increases.
The main finding in the vast majority of cases, however, was no change of concentration, with 1,898 such readings out of a total of 2,156 samples.
The greatest number of decreases were for chlordane (43), PCB (26), DDT (24) and cadmium (20). The greatest increases were for mercury (7), lead (7), zinc (6) and arsenic (5).