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Toxicity Testing Unit


EPA & NY approved WET Species including the fathead minnow
and waterflea for freshwater (top row) and sheepshead minnow
and opossum shrimp for estuarine or marine waters (bottom row)

Contact the TTU for more information

The Toxicity Testing Unit (TTU) administers and provides technical oversight of the Whole Effluent Toxicity (WET) testing program in accordance with Technical and Operational Guidance Series (TOGs) 1.3.2 - Acute and Chronic Toxicity Testing in the State Pollutant Discharge Elimination System (SPDES) Permit Program. In New York, WET testing is required at many municipal, industrial, and/or remediation facilities statewide. The Federal Clean Water Act (CWA) requires the restoration and maintenance of the chemical, physical, and biological integrity of the Nation's waters. WET testing plays an important role in meeting this objective. The goal of WET testing is to protect surface water quality by prohibiting the discharge of toxic pollutants in amounts toxic to aquatic life. These laboratory-based bioassays use representative test organisms common to most waters of the United States. The appropriate vertebrate and invertebrate organisms, either freshwater or estuarine/marine, are exposed to varying concentrations of effluent, and monitored for impacts to their survival, growth, and/or reproduction following approved Environmental Protection Agency (EPA) methods (leaves DEC website).WET testing methods are also used to conditionally authorize the use of various Water Treatment Chemicals (WTCs).

Similarly, the TTU also uses bioassays to evaluate toxicity in ambient surface waters (using the water flea) and aquatic bottom sediments and companion porewaters (using Microtox®). This testing is part of the Rotating Integrated Basin Studies (RIBS) program. Data can be found for both methods on DEC's InfoLocator by using the Aquatic Toxicity Monitoring layer.

View our fact sheet on the method of water quality assessment using toxicity testing data (PDF).

WET Training (PDF)

Luminescent Bacteria
Microtox® bioluminescent bacteria

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    Bureau of Water Assessment and Management
    Division of Water
    625 Broadway
    Albany, NY 12233-3502
    518-402-8179
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