Toxic Substances of Concern
Toxic substances are chemicals that, at some concentrations, can harm plants and animals, including humans. In general, they are found in low concentrations in Lake Champlain. However, Lake Champlain Basin Program studies have shown that contaminants accumulated in lake-bottom sediments may be having adverse effects on aquatic organisms at three sites of concern: Cumberland Bay, Burlington Harbor and Outer Malletts Bay. Mercury and polychlorinated biphenyls (PCBs) are present at low levels throughout the Lake and have accumulated in the tissues of several fish species, prompting Quebec, Vermont and New York to post fish consumption advisories.
The plan for the Lake Champlain Basin, Opportunities for Action lists toxic substance prevention and control as one of its highest priorities. It calls for further investigation and restoration of the most contaminated areas of the Lake, and prevention of additional toxic substance discharges to the Lake and its rivers.
The Lake Champlain Basin Program and its partners have been working to identify toxic sites in Lake Champlain and remedy them. In 2000, the New York State Department of Environmental Conservation finished dredging PCBs in Cumberland Bay at a cost of $35 million. Monitoring programs will continue to assess the site. Sediment contaminant levels are being measured in Burlington Harbor and tests are being conducted to determine whether the contaminants are harmful to aquatic animals.
Many groups throughout the Basin are also preventing pollution. Efforts include pesticide reduction workshops for farmers and homeowners, and programs to inform the dental community about proper mercury disposal. Citizens at home and at work can also prevent pollution by properly disposing household cleaners, batteries, and flourescent lightbulbs; using environmentally friendly cleaners; driving less and carpooling; and reducing pesticide use on lawns and gardens.
The Lake Champlain Basin Program reviewed the toxic substances found to date in Lake Champlain and ranked them as "high priority" and of "potential concern." Ranking was based on the extent and levels at which they are found, the risk that they may pose to human health, and the risk they may pose to the ecosystem. This set of priorities will be used to: 1) direct further research on presence and effects; 2) assist in source identification efforts; and 3) direct management efforts, including source reduction, treatment and remediation.
Toxic Substances of Concern Found in the Lake's Biota,
Sediment and Water
Group 1 and Group 2 substances are of highest concern because they are found in Lake Champlain at levels above standards or guidelines that help predict human health or ecosystem effects. Group 1 substances rank higher because they have been found lakewide and are known to accumulate in the tissues of fish and wildlife, while Group 2 substances have been found only in relatively localized areas such as bays and near where tributaries enter the Lake. The substances in Groups 3 and 4 are considered of "potential concern" because they are known to affect organisms, but at higher concentrations than have been found in Lake Champlain.Toxic Sources Include:
Among other sources, urban and agricultural stormwater runoff may contribute significant amounts of contaminants to surface waters. These substances include motor oil, pesticides, road de-icing chemicals, and metals. The amounts of these substances reaching streams, rivers and the Lake are difficult to quantify since the concentrations are generally low and stormflows are often difficult to sample. As urban areas are expanded in the Basin, the amount of stormwater runoff will increase and greater amounts of contaminants will be delivered.Learn More...
Design: Nicole L. Ballinger (LCBP) | Maps: Northern Cartographic and LCBP