Sediment toxicity is measured by a standard direct test of toxicity that has been applied at thousands of sites to measure the survival of amphipods (commonly found shrimp-like benthic crustaceans) exposed to sediments for 10 days under laboratory conditions. As in all tests of toxicity, survival is measured relative to that of amphipods exposed to reference sediment.

The pie graph shows the proportion of the NJ/NY Harbor Estuary that is good (green), fair (yellow), poor (red) or missing data (blue) for sediment toxicity. The small symbols on the map show the rating at a particular sampling location.