PRESENCE OF DIOXINS AND FURANS IN VEGETATION SAMPLES COLLECTED IN THENEIGHBORHOOD OF A MUNICIPAL SOLID-WASTE INCINERATOR

Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) we re analyzed by GC/MS in 24 vegetation samples collected in the vicinit y of a municipal solid waste incinerator. Samples were taken within a radius of 3000 m from the stack in each of the three main wind directi ons in that area. Total TEq levels for PCDD/Fs ranged between 1.07 ng/ kg (dry matter) and 3.05 ng/kg (dry matter), with median and mean valu es of 1.88 y 1.92 ng/kg (dry matter), respectively. OCDD/F and 1,2,3,4 ,6,7,8-HpCDD/F were the dominating dioxin and furan congeners found in vegetation samples. Although the highest PCDD/F level (3.05 ng TEq/kg ) was found at the north-west (1000 m from the stack) direction, for m ost congeners and contributors to Teq the highest concentrations were observed at distances less than 250 m from the facility. The present r esults should be of concern for future assessments on the correlation between decreases in the atmospheric PCDD/F emission from the incinera tor and the decline in the levels of PCDD/Fs in vegetation.