Our Water As prevailing winds and ocean currents carry PCBs toward the poles, these chemicals are still increasing in cetacean tissue in Antarctic and northern Pacific waters. There has been little or no decline in the widespread persistent organochlorine chemical pollution of marine animal tissue since the mid 1980s. Large cetaceans carry PCBs and structurally similar chemicals at or above the concentrations that are linked with significant neurological impairment in humans. Current background levels of PCBs, dioxins, and furans in humans have been found to alter thyroid hormone levels and weaken the offspring’s immune system. Mercury contamination of both freshwater and marine mammal tissue is increasing at a startling rate in some parts of the world. Mercury’s effect on the nervous system and intelligence is well documented. Recent findings suggest that the immune systems of some cetaceans, e.g. beluga whales, are exceptionally sensitive to mercury. Organotin (organic tin) compounds, such as those found in paint used on ships, continue to pose a threat to cetaceans’ food base and perhaps directly to their health. Organotin compounds interfere with sex organ development, often readily visible in marine animals lower in the trophic system, and interfere with reproductive success. They also attack the thymus gland, suppressing immune function. The atmospheric transport of currently-used pesticides to the Arctic, where they accumulate at the air-water interface, ice edges, and in surface fog, poses both a direct and indirect threat to cetaceans. Among these newly discovered compounds are several herbicides designed to inhibit photosynthesis. Their effects on essential algal and diatom blooms must be investigated for possible disturbance of the foundation of the food web on which cetaceans depend. These chemicals are invading the cetacean summering grounds where whales feast before they move south to fast for as long as six months. The herbicides are found in the highest concentrations at the same time of the year as the critical annual algal bloom. Today 40 percent of our waters are still too polluted for fishing and swimming. --CNN, Transcript of Clinton Remarks July 30 at New River (2/2)