Levels of PCDDs and PCDFs in grasses and weeds collected near a municipal solid waste incinerator

The concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/PCDFs) were determined in grass and weed samples collected in the vicinity of a municipal solid waste incinerator (Tarragona, Catalonia, Spain). Samples were collected at various sites within a radius of 1.5 km from the facility in each of the four main directions of the wind. PCDD/PCDF concentrations ranged from 0.15 to 62.09 ng Tequiv./kg (dry matter) with a median value of 0.328 ng Tequiv./kg (dry matter) and a mean value of 4.11 ng Tequiv./kg (dry matter). OCDD, followed by OCDF, was the predominant congener and contributor to Tequiv. Results were compared to the levels of PCDD/PCDF found in soil samples collected at the same time and place as the current grass and weed samples. The PCDD/PCDF profile was similar for soil and vegetation samples. The present results show that grasses and weeds can be an adequate indicator of PCDD/PCDF deposition from a municipal solid waste incinerator.