Analysis of dated sediment samples from the Newark Bay area for selected PCDD/Fs

To assess the magnitude and extent of 2,3,7,8-TCDD contamination, sediment cores from the Newark Bay estuary and contiguous waters were collected and dated by radiochemical methods. The core sections from two time horizons were analyzed for selected PCDD/Fs. The highest 2,3,7,8-TCDD concentrations were found in sediments from the sampling site nearest a chemical manufacturing facility on the Passaic River where 2,4,5-T had been synthesized. At this site and in Newark Bay sediments, 2,3,7,8-TCDD was the dominant TCDD isomer found, consistent with 2,4,5-T synthesis being a major source of the 2,3,7,8-TCDD.