Use of native mosses as biomonitors of heavy metals and nitrogen deposition in the surroundings of two steel works

A biomonitoring survey using the moss species Hypnum cupressiforme Hedw. was conducted in the surroundings of two steel plants located in the North of Spain. Levels of V, Cr, Ni, Cu, Zn, As, Cd, Hg, Pb and N were determined. Very high concentrations in the areas of study were detected when compared to nearby unaffected regions. Similar trends were observed for all the elements in the differently orientated transects, showing an appreciable influence of the NW prevailing winds of the region in the dispersion of pollutants, as well as a clear decreasing gradient in the concentrations of metals in mosses within a distance of 1500 meters from the facilities. A differentiation between the elements emitted by the chimney as result of the industrial activity (V, Cr, Ni, Cu and As) and those with a high presence in steel slag deposits (Zn, Cd, Hg and Pb) was observed. The range of contamination was also established by means of the Contamination Factor, indicating a category 4 out of 6 categories, which shows the high levels reported in the areas of study. A different dynamic was registered for nitrogen regarding the rest of the heavy metals analysed except for Hg, probably due to the elevated volatility and mobility of both elements, as well as their high persistence in the atmosphere.     

PCDD/F levels in the neighbourhood of a municipal solid waste incinerator after introduction of technical improvements in the facility

In 1998 and 1999, the concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were determined in soil and herbage samples collected in the vicinity of an old municipal solid waste incinerator (MSWI) (S. Adrià del Besòs, Barcelona, Spain). Just after the 1999 collection, an adaptation to the EU legislation on pollutant emissions from the stack was carried out in this facility. The purpose of the present study was to determine the current concentrations of PCDD/Fs in soil and herbage samples collected in the neighbourhood of the MSWI and to compare these concentrations with those obtained in the 1998 and 1999 surveys. During the period 1998-1999, an increase of 31% (P>.05) was found in the median PCDD/F levels in soils, while a reduction of 40% (P>.05) was observed in the period 1999-2000. Similarly, in the period 1998-1999 an increase of 41% (P>.05) was found in the levels of PCDD/Fs in vegetation, while a 30% decrease (P<.05) was seen in the period 1999-2000. Although after introduction of the technical improvements in the MSWI a notable reduction in the levels of PCDD/Fs in soil and vegetation has been noted, the median decreases have not been as great as it could be expected according to the very pronounced reductions in PCDD/F emissions from the stack. It indicates that other emission sources of PCDD/Fs also have a notable impact on the area under direct influence of the MSWI.     

Human exposure to dioxins through the diet in Catalonia,Spain: carcinogenic and non-carcinogenic risk

The main objectives of this study were to estimate the dietary intake of dioxins by the population of Catalonia, Spain, to determine which food groups showed the greatest contribution to this intake, and to assess the health risks potentially associated with the dietary dioxin intake. From June to August 2000, food samples were randomly acquired in seven cities of Catalonia. Dioxin concentrations were determined in 108 samples belonging to the following groups: vegetables, fruits, pulses, cereals, fish and shellfish, meats and meat products, eggs, milk and dairy products, and oils and fats. Estimates of average daily food consumption were obtained from recent studies. Total dietary intake of dioxins for the general population of Catalonia was estimated to be 95.4 pg WHO-TEQ/day (78.4 pg I-TEQ/day), with fish and shellfish (31%), diary products (25%), cereals (14%) and meat (13%) showing the greatest percentages of contribution to dioxin intake. The contribution of all the rest of food groups to the total dietary intake was under 20%. The non-carcinogenic risk index of dioxin intake through the diet was in the range 0.34-1.36, while the carcinogenic risk level was 1,360 excess cancer over a lifetime of 70 years. Our results corroborate the decreasing tendency in dietary intake of dioxins found in recent studies (2000-2001) from various countries.     

Dioxin and dibenzofuran concentrations in blood of a general population from Tarragona, Spain

The concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in plasma samples of 20 nonoccupationally exposed subjects living in the vicinity of a new hazardous waste incinerator (HWI), now under construction in Tarragona (Catalonia, Spain). The mean PCDD/F value was 27.0 pg I-TEQ/g lipid with a range from 14.8 to 48.9 pg I-TEQ/g lipid. All samples showed higher PCDD than PCDF levels. Although PCDD/F concentrations were higher in women (27.7 pg I-TEQ/g lipid) than in men (25.2 pg I-TEQ/g lipid), the difference was not statistically significant. While a significant correlation (r = 0.565, p < 0.01) between the age of the subjects and the levels of PCDD/F in plasma could be observed, no significant differences were found in relation to the specific residential area. The plasma concentrations of PCDD/F obtained in the current study are discussed and compared with the results of similar investigations reported in the last two years.     

PCDDs and PCDFs in food samples from Catalonia, Spain. An assessment of dietary intake

Food samples from local markets and supermarkets of Tarragona (Catalonia, Spain) were analyzed for PCDD/F concentrations. On lipid basis, PCDD/F levels in meat, fish, eggs, and fats and oils were similar or lower than those found in other countries. By contrast, in general terms PCDD/F levels in milk, vegetables, and cereals showed higher levels than those previously reported. The total dietary PCDD/F intake by the population of Tarragona was estimated to be 210 pg I-TEQ/day. This value is higher than the dietary intake of PCDD/Fs found in a number of surveys from other countries. However, when total dietary intake of PCDD/Fs was calculated including only fish and seafood, meat, milk and dairy products, eggs, and fats and oils, a dietary intake of PCDD/Fs of 117 pg I-TEQ/day was obtained. This intake is in the same range than that reported for different regions and countries. The results of the present study show that food groups such as vegetables, fruits, and cereals should not be excluded to estimate the total dietary intake of PCDD/Fs by general populations, especially in those countries and/or regions in which their consumptions are notable.     

Horizontal,vertical and seasonal distributions of epiphytic hydrozoa on the algaHalimeda tuna in the Northwestern Mediterranean Sea

The thalli ofHalimeda tuna (Ellis & Solander) grow horizontally from rocky surfaces and present an upper and lower surface which can be colonized by epiphytes. Thalli ofH. tuna were collected twice a month from March 1985 to March 1986 at Tossa de Mar (northeast Spain). Thirty five species of hydroid were recorded living onH. tuna thalli; of these, the 15 most abundant species were classified into three groups on the basis of their horizontal zonation on the thalli: those most abundant on the proximal, medial or distal articles. Those hydroids common on the proximal (oldest) articles were relatively large and were present throughout the year, those common on the medial articles were smaller and often occurred in dense monospecific patches, while those common on the distal (youngest) articles were present for only short periods and were the most opportunistic hydroids found onH. tuna. We hypothesize that this zonation reflects interspecific niche-selection, enabling successful competition for space with other hydroids, algae and bryozonas. Three hydroid species were more abundant on the upper surfaces of the algae than on the lower, probably because of gravitationally enhanced settlement of planula larvae coupled with (unusually) limited hydrorhizal growth on the underside. Three opportunistic species were more common on the lower surfaces of the thalli, possibly reflecting the greater availability of substratum in the shade, where epiphytic algae were less abundant. Many hydroids declined in abundance in summer because of the death of old thalli, the growth of new thalli and of apical articles on existing thalli, and possibly because of interspecific competition with epiphytic algae. The death of old thalli and the growth of new thalli reduced the abundance of epiphytic algae; this may have facilitated the increase in abundance of hydroids recorded in the autumn.     

Concentrations of PCDD/PCDFs and PCBs in fish and seafood from the Catalan (Spain) market: estimated human intake

The concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs) in samples from 14 fish and seafood species widely consumed by the population of Catalonia, Spain, were measured. These samples were randomly purchased independently of their geographical origin. The intake of PCDD/Fs and PCBs through consumption of these species was also estimated for various age and sex groups of this population. The highest and lowest levels of PCDD/Fs and dioxin-like PCBs (DL-PCBs) were found in red mullet and shrimp, respectively. For a standard adult man (70 kg body weight), the intake of PCDD/Fs plus DL-PCBs through consumption of fish and other seafood was estimated to be 38.0 pg WHO-TEQ/day. Tuna, hake, and sardine were the species with the highest contribution to this intake. The results of this study indicate that, in general terms, the dietary habits of the population of Catalonia (Spain) regarding fish and seafood consumption do not contribute remarkably to increase PCDD/F and DL-PCB intake.     

Atmospheric deposition of PCDD/Fs near an old municipal solid waste incinerator: levels in soil and vegetation

The levels of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) were determined in soil and vegetation samples taken from 24 sites in the vicinity of an old municipal solid waste incinerator (San Adrià del Besòs, Barcelona, Spain). Duplicate samples were collected within a radius of 3 km from the stack. PCDD/F concentrations in soils ranged from 1.22 to 34.28 ng I-TEQ/kg (d.m.) with median and mean values of 9.06 and 12.24 ng I-TEQ/kg, respectively. In turn, the levels of PCDD/Fs in vegetation samples ranged from 0.33 to 1.98 ng I-TEQ/kg (d.m.), with median and mean values of 0.58 and 0.70 ng I-TEQ/kg, respectively. Although the present PCDD/F concentrations in soil samples were higher than those recently found in soils taken near other incinerators from Catalonia, they are of the same order of magnitude than the levels of these pollutants found in incinerators from other countries. By contrast, the concentrations of PCDD/Fs in herbage samples were comparable to those found in recent surveys carried out in Catalonia.     

PCDD/F concentrations in milk of nonoccupationally exposed women living in southern Catalonia, Spain

Concentrations of 17 toxic 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) have been determined in pooled samples of breast milk from 15 mothers living in two residential areas (Tarragona downtown and an industrial area) in the vicinity of a new hazardous waste incinerator (HWI), now under construction in Tarragona (southern Catalonia, Spain). PCDD/Fs in human milk samples ranged between 5.9 and 17.1 pg I-TEQ/g fat (162-498 pg I-TEQ/l), with a mean value of 11.8 pg I-TEQ/g fat (310.8 pg I-TEQ/l). The percentages of fat ranged between 1.53 and 3.52. Although PCDD/F levels in milk from mothers living in the industrial area were found to be slightly higher than those observed in women living Tarragona downtown, most differences did not reach the level of statistical significance. In general terms, PCDD/F concentrations in human milk (pooled) samples of mothers living in the area of Tarragona are similar or lower than those previously reported for most industrialized countries.     

Human exposure to polychlorinated naphthalenes through the consumption of edible marine species

The concentrations of polychlorinated naphthalenes (PCNs) were determined in samples of 14 edible marine species (sardine, tuna, anchovy, mackerel, swordfish, salmon, hake, red mullet, sole, cuttlefish, squid, clam, mussel and shrimp), which are widely consumed by the population of Catalonia, Spain. The daily intake of PCNs associated with this consumption was also determined. A total of 42 composite samples were analyzed by HRGC/HRMS. The highest PCN levels (ng/kg of fresh weight) were found in salmon (227) followed by mackerel (95) and red mullet (68), while the lowest levels of total PCNs corresponded to shrimp (4.9) and cuttlefish (2.7). With the exception of cephalopods and shellfish species, in which tetra-CN was the predominant homologue, penta-CN (60%) was the predominant contributor to total PCNs. For a standard male adult, PCN intake through the consumption of edible marine species was 1.53 ng/day. The highest contributions to this intake (ng/day) corresponded to salmon (0.41), sole (0.28) and tuna (0.24). Concerning health risks, species-specific TEFs such as those reported by WHO and NATO for PCDD/Fs and dioxin-like PCBs are not currently available for PCN congeners. Although in general terms the results of the present study do not seem to suggest specific risks derived from exposure to PCNs through fish and seafood consumption, to establish the contribution of individual PCN congeners to total TEQ is clearly necessary for the assessment of human health risks.