Search

The atmospheric Pb emissions (1901–2019), from one of the world’s largest non-ferrous metallurgical complexes (Met-Mex in Torreon, Mexico), were estimated based on historical records of modifications in the design, processes, and production volumes. Eight historical periods, with differing amounts of Pb emissions, were distinguished: (1) Essentially no controls (1901–1960); (2) migration to limited controls (1961–1972) by conversion to a Pb-Zn smelter-refining complex and installation of SO2 collectors in 1961–1963; (3) completion to limited control (1973–1977) by the installation of a third H2SO4 collector and a low-efficiency filtration system; (4) maintenance of limited control with no changes (1978–1987); (5) migration to strict control (1988 to 1998) by updating H2SO4 collectors and installation of fertilizer and SO2 liquid extraction plants; (6) completion to strict control (1999–2000) by the installation of state-art technology filtration systems and roofing working areas; (7) migration to abatement (2001–2003) by implantation of good management practices; and (8) maintenance of abatement following good management practices (2004–2019). Based on differences between those periods, we reconstructed the evolution of the Pb emission reduction efficiency (ER in %) and Pb emission factors (EF in gram/ton) for the Torreon complex. Pb emitted by the complex over the past 118 years totaled 23,350–27,580 t, with most of it (63–75%) occurring when emission controls were negligible (pre-1960 period). In comparisons with other facilities worldwide (e.g., the USA, Canada, and Europa), the modification in Met-Mex for control the Pb emission occurred several years. Emissions from the primary Pb-Zn smelter-refining are released mostly to the atmosphere from the sintering, smelting, drossing, and refining. While Pb emissions from the facility have declined by over an order of magnitude to contemporary levels (≤ 12.6 t/year), the current Pb rates still account for atmospheric Pb levels that are 2–3 times higher the USEPA standard and still constitutes a major health threat in Torreon.

Little is known about the particles attached on the surfaces of coarse ( 150 μm) road-deposited sediments (RDS), which are potential contributors of stormwater pollution. Therefore, the size distributions and heavy metal (including Cu, Pb, Zn, Cr, and Ni) pollution of RDS were evaluated taking these attached particles into consideration. Moreover, the relationships of RDS contamination with traffic types were further discussed. The results showed that 22, 22-38.5, 38.5-150, 150 μm RDS and attached particles accounted for 2.1 ± 1.8%, 8.5 ± 5.7%, 50.7 ± 6.8%, 38.6 ± 8.3%, and 2.0 ± 1.2% of total RDS mass, respectively. The size distributions of attached particles were comparable to that of representative stormwater particles, suggesting their great potential to contribute stormwater particles by desorption. The Zn pollution of attached particles was remarkable, which was significantly higher than that of both fine ( 150 μm) and coarse ( 150 μm) RDS. The Cu and Pb pollution were comparable to that of fine RDS, which were significantly higher than that of coarse RDS. Conversely, the Cr and Ni pollution were comparable to that of coarse RDS, which were significantly lower than that of fine RDS. Traffic types were found to be closely related with RDS contamination, and thus are indicative of specific RDS pollution. For example, electrombile in old residential area is indicative of abnormal Pb pollution due to past emissions of leaded gasoline; lorry is indicative of remarkable Zn pollution of 22 μm RDS due to abrasion of tires and metallic substances. Accordingly, traffic type is accessible to identify the typical pollutants in RDS to promote effective RDS management.

The use of bryophytes as an indicator of environmental quality has been addressed on numerous occasions and in different places of the world under a variety of conditions. However, in Latin America their use is still limited. In the study described here, the presence and distribution of the bioaccumulation of lead in bryophytes has been evaluated in both contaminated and uncontaminated sites in Villavicencio (Colombia) and its surroundings. Villavicencio is a medium-sized city that is similar in size to many other cities in Latin America. A total of 52 samples of bryophytes were collected, of which 43 belong to points distributed in urban areas of the city (residential, commercial, highway), and the remaining nine are from uncontaminated areas (reference) taken in the surroundings of the city. The samples were treated with acid (nitric and hydrochloric) and subsequently measured by atomic absorption spectrometry. It was found that Pb concentrations in the commercial sector are between 1 and 6 times higher than in the residential and highway sectors. Spatial distribution maps of lead over the sampled territory were created using Arc-GIS 10.1. It is noteworthy that the values obtained are higher than those found in European cities.

Due to rapid growth of industrialization and human activities, such as mining and smelting, lead (Pb) has become a major environmental contaminant. As Pb can pose risks to human health, preventing Pb pollution in wheat is important for food safety, requiring accurate verification of pollution sources. Pb concentrations and isotope ratio levels in soil, in the atmosphere, and wheat tissue (root, stem, leaf, grain) in an area of high-Pb deposition (in the vicinity of a Pb smelter in Jiyuan city) and an area of low deposition (the northwest suburb of Zhengzhou city) were examined. The Pb isotope ratio and the binary mixed model were used to quantify the contribution of soil and atmospheric deposition to Pb content in wheat tissues. Results show that Pb content in soil, atmospheric deposition, and wheat in the high deposition area were significantly higher than those in the low deposition area. Pb content in soil, atmospheric deposition, wheat roots, stems, leaves, and grains in the high-deposition area were 355.32 ± 14.78, 5477.90 ± 187.85, 158.72 ± 9.56, 21.36 ± 1.72, 26.49 ± 1.96, and 0.94 ± 0.02 mg kg-1, respectively. Pb content in the low-deposition area were 6.10 ± 0.75, 78.50 ± 4.35, 2.47 ± 0.23, 1.03 ± 0.07, 2.11 ± 0.13, and 0.08 ± 0.01 mg kg-1, respectively. The Pb isotope ratio recorded obvious differences between soil and atmospheric deposition in the two areas. Combined with the significant correlation between Pb isotopes in various tissues of wheat and environmental media, and analysis of the isotopic composition characteristics of wheat and environmental media, in the high-deposition area, the contribution rate of atmospheric deposition in wheat roots, stems, leaves, and grains was 14%, 66%, 84%, and 77%, respectively. And the soil contribution rate was 86%, 34%, 16%, 23%, respectively. In the low-deposition area, the contribution rate of atmospheric deposition in wheat roots, stems, leaves, and grains was 49%, 73%, 93%, and 83%, respectively. And the soil contribution rates were 51%, 27%, 7%, and 17%, respectively. In the low-Pb deposition area, the contribution rate of atmospheric deposition in wheat was higher than that in the high-deposition area. Atmospheric deposition was the main source of Pb in grains, leaves, and stems of wheat in different depositional areas. Pb in wheat roots mainly derives from soil, and the Pb contribution rate of soil to wheat roots in the high-deposition area was significantly higher than that in the low-deposition area.

In order to trace the source of Pb pollution in wheat, the contribution ratio of soil and atmospheric fallout source was quantified based on stable isotope ratios. Results showed that the average Pb content of soil was significantly lower than that of fallout, and Pb in the fallout had a higher weak acid fraction than soil. Pb in wheat had a distinct distribution in its tissues and the content of Pb in wheat roots was significantly higher than it in shoots. The 206Pb/207Pb ratio of soil was significantly higher than that in atmospheric fallout (p

In the Anthropocene era, an immersion of toxic substances, i.e., trace metals, has been enhanced in the marine environment not only due to urban sprawl and industrial development but predominantly owing to incongruous management and lack of sustainable approaches. The coastal region of Pakistan shares a similar obstacle as most of the developing countries confronted. Therefore, this study was designed to investigate concentrations of eight metals (Cu, Fe, Zn, Ni, Co, Pb, Cr, and Cd) in sediment and Dotillid crab, Ilyoplax frater, at three tidal creeks in Karachi, Pakistan. All metals in sediments and crabs were analyzed by atomic absorption spectrometer. The sediment pollution was evaluated by contamination degree (CD) and potential ecological risk index (RI). After depicting the metal pollution in sediments, metal accumulation, and contamination in benthic crab were investigated through total metal concentrations in crabs, accumulation factor (AF), correlation analysis, and regression analysis. The results exhibited substantial differences in the concentrations of Zn, Ni, Pb, Cr, and Cd among the tidal creek sediments. Contamination factors indicated that the Cd and Pb had the highest sharing in sediment pollution, and the tidal creeks classified as moderately contaminated. All metal accumulations in Dotillid crabs showed notable spatial variations, and accumulation factors (AFs) for most of the metals were > 1.0, signifying the strong bioaccumulation of metals in crabs. Particularly, Cu, Co, and Cd levels were considerably greater (two to three times) in Dotillid crabs compared to creek’s sediments, even though they don’t share any relationship between two matrixes. Hydrographical and sedimentological traits also revealed significant interactions with metal levels in sediments and crabs. A substantial association was also noticed in Fe, Ni, and Pb between sediments and crabs. Interestingly, most of the metal AFs showed a notable inverse correlation with the environmental matrix. Exceptionally, a strong positive correlation found between the Pb concentration in crabs and sediments suggested that I. frater probably acts as an indicator of Pb pollution.

In this study, we determined the concentrations of As, Cd and Pb in the shaft of all primary flight feathers from ten tawny owl (Strix aluco) specimens, with the aim of selecting which shaft of the corresponding primary feather should be used in biomonitoring surveys to enable inter-individual comparisons of the levels of these metals. The birds had died between 2006 and 2013 and their bodies were stored in the various Wildlife Recovery Centres in Galicia (NW Spain). The analyses revealed a high degree of inter-shaft variability, mainly in the concentrations of As and Cd. However, it was possible to identify the most representative samples in each case: for As, the shaft of primary flight feather number 5 (S5) (which represented 11% of the total As excreted in all of the primary flight feathers); for Cd, the shaft of primary flight feather number 2 (S2) (11% of the total excreted); and for Pb, the shaft of primary flight feather number 8 (S8) (14% of the total excreted). However, the difficulties associated with the analytical determination of these pollutants in the shaft should be taken into account when this technique is applied in biomonitoring studies.

Tagetes minuta L. is a plant which accumulates Pb under certain conditions, making it a candidate for phytoextraction projects because it also produces marketable essential oils without detectable Pb levels. Although extraction efficiency has been shown to significantly vary between individuals, these results have been obtained using only historically exposed populations, which leads to the questions: Is the ability to tolerate and accumulate Pb a property of the species? Or is it a characteristic of some individuals from a historically exposed population? In this context, a greenhouse experiment was performed to analyse the intrapopulation and interpopulation variability in response to Pb among individuals from historically unexposed and exposed populations. In addition, we also attempted to identify relationships between certain capabilities (toleration and accumulation of Pb) and the physiological parameters related to oxidative stress or the volatile compounds of the essential oils. The Pb concentration was determined by total reflection X-ray fluorescence, physiological parameters were obtained by spectrophotometry, and essential oils were analysed by gas chromatography. The results demonstrated that adequate tolerance and accumulation capabilities are present in T. minuta, irrespective of the exposure history. These findings may be associated to a hormesis response, which includes enhancement of pigments, biomass production and the uptake of other heavy metals such as micronutrients. Nevertheless, the historically exposed population had a better tolerance to Pb, since it presented defence characteristics reflected in the essential oil composition and in the avoidance of damage at the lipid peroxidation level after Pb uptake. Fil: Miranda Pazcel, Eliana Melisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Nacional de Córdoba; Argentina Fil: Wannaz, Eduardo Daniel. Universidad Nacional de Córdoba. Facultad de Cs.exactas Físicas y Naturales. Cátedra de Química General; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Pignata, Maria Luisa. Universidad Nacional de Córdoba. Facultad de Cs.exactas Físicas y Naturales. Cátedra de Química General; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Salazar, María Julieta. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina

Atmospheric lead (Pb) pollution during the last century in central Yunnan province, one of the largest non-ferrous metal production centers in China, was reconstructed using sediment cores collected from Fuxian and Qingshui Lakes. Lead concentrations and isotopic ratios ((207)Pb/(206)Pb and (208)Pb/(206)Pb) were measured in sediment cores from both lakes. The operationally defined chemical fractions of Pb in sediment core from Fuxian Lake were determined by the optimized BCR procedure. The chronology of the cores was reconstructed using (210)Pb and (137)Cs dating methods. Similar three-phase variations in isotopic ratios and enrichment factors of Pb were observed in the sediment cores from both lakes. Before the 1950s, the sediment data showed low (207)Pb/(206)Pb and (208)Pb/(206)Pb ratios and enrichment factors (EFs=~1), indicating that the sedimentary Pb was predominantly of lithogenic origin. However, these indices were increased gradually between the 1950s and the mid-1980s, implying an atmospheric Pb deposition. The EFs and isotopic ratios of Pb reached their peak during recent years, indicating aggravating atmospheric Pb pollution. The average anthropogenic Pb fluxes since the mid-1980s were estimated to be 0.032 and 0.053 g m(-2) year(-1) recorded in Fuxian and Qingshui cores, respectively. The anthropogenic Pb was primarily concentrated in the reducible fraction. Combining the results of Pb isotopic compositions and chemical speciations in the sediment cores and in potential sources, we deduced that recent aggravating atmospheric Pb pollution in central Yunnan province should primarily be attributed to regional emissions from non-ferrous metal production industries.

Extensive mining took place in Spain during the Iron Age and Roman times, although a detailed chronology is still lacking due to the inherent difficulties in dating mining structures. In this study ...

To help reduce risks of heavy metal pollution, two pot experiments were conducted to investigate the variations, transfer potential, and stability of Cadmium (Cd) and Lead (Pb) accumulations in celery (Apium graveolens L.) and to screen for low Cd and Pb accumulative cultivars. The maximum differences in shoot Cd concentration were 4.7-fold under low-Cd exposure and 3.3-fold under high-Cd exposure. These genotype variations in Cd accumulation are sufficiently large to help reduce Cd contamination risk in soil by using the Low-Cd-Accumulative genotypes. Cd accumulation of the Low-Cd-Accumulative genotypes is significantly positive correlated with Pb accumulation. Evidence obtained proves that Cd and Pb accumulations in celery are stable and genotype-dependent at the cultivar level. The presence of high-Pb contamination in soil promoted Cd accumulation in shoots of celery. Celery is considered a species with high risks in Cd pollution and low risks in Pb pollution. Among the tested cultivars, cv. Shuanggangkangbing (SGKB) had the lowest shoot Cd and Pb accumulating abilities, and thus is the most important material for breeding of pollution-safe cultivars (PSCs) to minimize Cd and Pb accumulations in celery.

Lead (Pb), as an environmental hormone, acts as an estrogen in animal and human bodies, and its environmental pollution can result in many procreant anomalies, such as maladjustment of incretion, weakening of pro-creation function and descending of genital immunity. Experiments on pot-growth of paddies and corns in this study indicated that these crops did not show any macro-toxic symptoms in the observed contents of Pb added (0–4000 mg/kg) in soils. However, lead in soils can be easily absorbed by crops and accumulated in the different parts of plants. Statistical analysis showed that Pb contents in the crops are strongly positively correlated to the Pb contents in soils. In the crops, the Pb contents of roots are highest, tens to thousands of times those of straws and seeds. It is suggested that the root is a barrier of Pb absorbed by straws and seeds. Based on this fact, Pb pollution in soils can be gradually reduced by planting crops and subsequently removing the roots from the soil. This biotechnology may be used in environmental remediation, which embraces the quality of sustainable agricultural economy and a healthy environment.

KIZILKAYA, RIDVAN/0000-0001-7475-9851 WOS: 000239890200025 PubMed: 16917718 In this study, the relationship between some physico-chemical properties of soils and lead contamination in soil due to emission from industrial operations in Samsun province of Turkey was investigated. The extent of timely contamination was studied by comparing the obtained results with the results of the study conducted in the same region in 1998. An area of 225 km(2) (15 km x 15 km), which was divided into 1000 x 1000 m grid squares (16 lines in the east and south directions), was selected within the industrial area. The total of 256 grid points was obtained and soil samples were collected from three depths (0-5, 5-15, and 15-30 cm) of each grid center in 2004. The total Pb concentrations of soil samples were determined as 65.84-527.04 mu g g(-1)at 0-5 cm in depth, 58.50 - 399.54 mu g g(-1) at 5-15 cm in depth, and 44.65-330.07 mu g g(-1) at 15-30 cm in depth. DTPA-extractable Pb concentrations of soils were found to be in the range of 1.52-9.03 mu g g(-1)supercript stop, 0.54-7.09 mu g g(-1), 0.19-6.13 mu g g(-1)supercript stop at 0-5, 5-15, and 15-30 cm depths, respectively. There were significant relationships between both total or DTPA-extractable Pb concentrations and selected physico-chemical properties of soil. According to enrichment factor (EF) values calculated from the total Pb concentrations, 11.3% of the study area (225 km(2)) was enriched with Pb in high level, but 77% of the area was in significant enrichment level with Pb. The average total and DTPA-extractable Pb concentrations increased as 11 and 13%, respectively in comparison with the results of 1998.

Aerosol Pb pollution in Teheran was repeatedly measured at nine crossroads in the city from April to November 1976. The mean value of atmospheric Pb in the city was 3.6 μg m−3. The average values obtained for the Pb in the air of the crossroads were close to each other except in the southern parts of the city where it was higher. Stagnation of motor vehicles and higher dustfall may have a role in this increase. Since industrial Pb pollution is not significant in Teheran, it was concluded that the contamination by Pb in the city is mainly from gasoline consumption.

Aerosol Pb pollution in Rome was simultaneously measured at four different places and at two different levels (0.5 and 1.5 m) in April, September, November 1972 and January 1973.

Sufficient evidence has accumulated during the past decade to suggest that environmental Pb may be responsible for a deterioration in the mental and behavioral performance of some children. A knowledge of the pathways by which environmental Pb reaches the body is therefore important in the assessment and control of environmental Pb pollution. These pathways are discussed and it is argued that Pb in dust is one of the more useful indices of contamination of the environment by Pb. Those studies from which a quantitative relationship between blood-Pb level and Pb-in-dust concentration can be inferred are listed, and some theoretical consideration of the relationship is given. In conclusion, a Pb-in-dust concentration which; if exceeded on a widespread scale in residential areas, demands some action by the controlling authority is suggested.

Lead pollution in Baghdad City was studied. Several potential sources of Pb pollution were investigated, among which are leaded gasoline, battery manufacturing, and printing press type. The study included the analysis of blood samples from males and females of different ages and professions. Particular attention was given to workers who are in direct contact with Pb materials in order to discover whether local contamination is taking place or not. In addition, samples of palm leaves were collected from about twenty five different parts of Baghdad in 1978 and again in 1980 in order to study the distribution and relative increase in Pb deposition caused by vehicles using leaded gasoline. The results were compared with similar samples from less crowded cities. The results of this survey have shown that Pb pollution exists; its scale, however, can not be determined accurately until more data are obtained.

Chemical analysis of samples of needles of Aleppo pine (Pinus halepensis), humus and mineral soil collected in the vicinity of the Pb-smelter in Lavrion, Attica, showed that an area of about 2 km around the smelter is heavily polluted primarily with Pb and also with Zn, S and F−. Most of the Pb was found accumulated in the humus and the top layer of the mineral soil.

Blood lead (B-Pb) and erythrocyte zinc protoporphyrin (ZPP) were measured in 78 mothers at delivery and in cord blood from 48 infants living in an area with low atmospheric Pb pollution. Median B-Pb was 35 micrograms/l (range 6-63) in mothers and 20 micrograms/l (range 6-50) in infants (P less than 0.0001), and the values were significantly correlated (rs = 0.73, P less than 0.0001). Mean B-Pb infant/B-Pb mother ratio was 0.7 (range 0.2-1.4). Mothers had lower ZPP (median 1.6 microgram/g Hb) than infants (median 2.9) (P less than 0.0001). ZPP in mothers showed a stronger relation to iron status (serum transferrin, serum ferritin) than to B-Pb (rs = 0.22, P less than 0.05). B-Pb was correlated to serum iron both in mothers (rs = 0.28, P less than 0.02) and infants (rs = 0.33, P less than 0.03). The present B-Pb levels are lower than previously reported in Scandinavia, probably due to the general decline in atmospheric Pb pollution.