Annual variation in the levels of metals and PCDD/PCDFs in soil and herbage samples collected near a cement plant.

In May 2000, the levels of a number of metals (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Sn, Tl, V and Zn) and polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in soil and herbage samples collected near a cement plant from Sta. Margarida i els Monjos (Catalonia, Spain). To determine the temporal variation in the concentrations of metals and PCDD/PCDFs, in May 2001 soil and herbage samples were again collected at the same sampling points and analyzed for the levels of metals and PCDD/PCDFs. In general terms, metal concentrations in soils did not change between May 2000 and May 2001, while significant decreases in the levels of Cr, Ni and V were found in herbage. On the other hand, no significant differences in the mean I-TEQ values of PCDD/PCDFs were found in soil and herbage samples. The results of this survey show that according to the annual variation in the levels of metals and PCDD/PCDFs the environmental impact of the cement plant on the area under its direct influence is not relevant.

PCDD/F and metal concentrations in soil and herbage samples collected in the vicinity of a cement plant.

In May 2000, the levels of a number of metals (As, Cd, Pb, Hg, Zn, Co, Cu, Mn, Sn, Tl, Cr, Ni and V) were determined in 16 soil and herbage samples collected in the vicinity of a cement plant from Sta. Margarida i els Monjos (Catalonia, Spain). Metal concentrations were also analyzed in air filters from three sampling stations placed nearthe facility. For most metals, concentrations were similar or even lower than previously reported values for other areas from Catalonia. On the other hand, the levels of polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) were also determined in four soil and 16 herbage samples. Mean values were 0.37 and 0.16 ng I-TEQ/kg for soils and herbage, respectively, values which in comparison with data from other surveys are rather low. No significant differences between metal and PCDD/F concentrations in samples collected at distances lower or greater than 3.5 km of the facility were noted. The current results show that the cement plant has a low impact on the metal and PCDD/F levels in the environment under direct influence of the facility. These results should be of interest to assess future temporal variations in the levels of metals and PCDD/Fs in this area.

Temporal variation of PCDD/PCDF levels in environmental samples collected near an old municipal waste incinerator.

In 1996 and 1997, the levels of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) were determined in soil and herbage samples taken from 24 sites in the vicinity of an old municipal solid waste incinerator (Montcada, Barcelona, Spain). To determine the temporal variation in the concentrations of PCDD/Fs, recently 24 soil and 24 herbage samples were again collected at the same sampling points and analyzed for PCDD/F levels. In the current survey, PCDD/F concentrations in soils ranged between 0.06 and 127 ng I-TEQ kg(-1) (dry matter), with median and mean values of 4.80 and 9.95 ng I-TEQ kg(-1) (dry matter), respectively. In turn, the levels of PCDD/Fs in herbage samples ranged from 0.40 to 1.94 ng I-TEQ kg(-1) (dry matter), with median and mean values of 0.86 and 0.95 ng I-TEQ kg(-1) (dry matter), respectively. The comparison with the data obtained in 1996 and 1997 show that while PCDD/F concentrations in herbage samples decreased substantially during the last two years, no significant differences in the levels of PCDD/Fs in soils were noted. On the other hand, the potential intake of polluted soils from the vicinity of the plant would not imply any significant health risk for the general population living in the area under influence of the facility.

Assessment of baseline levels of PCDD/F in soils in the neighbourhood of a new hazardous waste incinerator in Catalonia, Spain.

In order to determine the baseline contamination by polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) in an area from Catalonia (Spain), which will be under the influence of a new hazardous waste incinerator, PCDD/F concentrations were measured in 40 soil samples collected in the vicinity of the facility now under construction. Thirty samples represented rural soils and 10 samples urban soils. PCDD/F concentrations ranged between 0.08-8.4 ng I-TEQ/kg for rural soils and 0.63-24.2 ng I-TEQ/kg for urban soils. The mean value for the 40 samples was 1.64 ng I-TEQ/kg (dry matter). The current PCDD/F levels and profiles are comparable to those found in soils from other countries. The PCDD/F concentrations found in this study show that at present the contamination by PCDD/F in soils of the examined area is rather low.

PCDD/Fs in soil samples collected in the vicinity of a municipal solid waste incinerator: human health risks.

The concentrations of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) were determined in soil samples taken from 24 sites in the vicinity of a municipal solid waste incinerator (Montcada, Barcelona, Spain). Samples were collected within a radius of 3 km in each of the three main directions of the wind rose in that area. Hepta- and octa-CDDs were the predominant congeners and contributors to TEQ. PCDD/F levels ranged from 0.30 to 44.26 ng TEQ/kg (dry matter), with median and mean values of 3.52 and 6.91 ng TEQ/kg, respectively. The highest and lowest PCDD/F concentrations were found at 750 m (44.26 ng TEQ/kg) and 3000 m (0. 30 ng TEQ/kg) from the stack, while the PCDD/PCDF ratio was 1.78. The health risk analysis of the data shows that the PCDD/F intake from soils is substantially lower than the tolerable daily intake for toxicologic (other than cancer) effects of PCDD/Fs.