Atmospheric Lead Concentrations Research Articles

Atmospheric lead concentration distribution in traffic air monitoring stations in Northern Taiwan

Atmospheric lead concentration distribution in traffic air monitoring stations in Northern Taiwan

Impact of reduction of lead in gasoline on the blood and hair lead levels in the population of Tarragona Province, Spain, 1990–1995

The limitation in the use of lead in Spanish gasoline has induced a resulting decrease in atmospheric lead concentrations, a remarkable reduction in the lead levels of edible vegetables, as well as a marked decrease in the dietary lead intake of the population of Tarragona Province (Catalonia, N.E. Spain). The present study evaluates the impact of such decreases on blood lead values and hair lead concentrations in an adult and children population of that region. A total of 250 adult participants between 16–65 years of age and 252 children were included in the study. Blood and hair samples were subjected to lead analyses by graphite furnace atomic absorption spectrophotometry and inductively coupled plasma spectrometry, respectively. A substantial decline in both, blood lead levels in adults (47.5%) and lead concentrations in children's hair (53%) was observed. During the period 1990–1995, blood lead levels were reduced from 12.0 μg dl−1 to 6.3 μg dl−1, while the hair lead concentrations decreased from 8.8 μg g−1 to 4.1 μg g−1. These decreases were noted for all the subgroups (sex, age and place of residence) examined, and were mainly attributable to the reduced leaded gasoline consumption.

LEAD IN HUMAN BLOOD FROM CHILDREN LIVING IN CAMPANIA, ITALY

Blood lead (PbB) levels were determined in children living in Campania (in Naples and in a rural zone in the district of Caserta). Atmospheric lead (PbA) concentration in these considered areas was monitored for 1 yr (1993-1994). The children tested were questioned about common sources of lead, other than atmospheric, relating to their living and dietary habits. The PbB levels in children living in Naples were, at the 50th percentile, 13.8 micrograms/dl in males and 13.7 micrograms/dl in females; in children living in the rural area the median PbB levels were 8.9 micrograms/dl in males and and 8.8 micrograms/dl in females. The annual mean values of atmospheric lead were 1.15 +/- 0.24 micrograms/m3 in Naples and 0.23 +/- 0.07 micrograms/m3 in the rural area. Significant and congruent mean differences between urban and rural sites were found in children's blood and concurrent air lead. Considering the PbB level of 10 micrograms/dl as the maximum level that is not associated any known adverse effect in children, the Neapolitan group can be considered at risk of chronic intoxication by lead.

Changes in the Level of Atmospheric Lead Concentrations in Cities and Estimation of Lead Inhalation and Absorption in Japan Today

Changes in the Level of Atmospheric Lead Concentrations in Cities and Estimation of Lead Inhalation and Absorption in Japan Today

Relative effects of climate and source strength on atmospheric lead concentrations in Auckland, New Zealand

Atmospheric lead levels were examined to assess the consequences of the 46 percent reduction in the lead content of premium grade petrol in New Zealand. Since this change was implemented in July 1986 observed levels of atmospheric lead decreased by 38 percent, but all or part of this reduction may have been due to factors other than fluctuations in lead emissions, notably variations in climate. Analysis of detailed atmospheric lead, meteorological and traffic data measured contemporaneously provided insight into the atmospheric processes influencing lead levels in Auckland and formed the basis of a statistical model capable of predicting monthly lead concentrations. The model was used to predict lead levels in Auckland for the period July 1986 through to July 1989 in the absence of any reduction in the lead content of petrol. Comparison with values observed for the same period showed that all of the reduction in atmospheric lead levels since July 1986 can be attributed to the reduction in the lead content of petrol. Policy planning implications of such a finding are considered.

Temporal variability of atmospheric lead concentrations and fluxes over the northwestern Mediterranean Sea

Beginning in 1985, daily 24‐hour aerosol samples were collected on 0.4‐pm pore size filters at a coastal location in northwestern Corsica. Total atmospheric deposition (wet + dry) were sampled between February 1985 and October 1987 with a collection period of about 15 days. As indicated by three‐dimentional air mass trajectories, lead aerosol particles collected at this site are primarily derived from European continental source regions. The variability of lead aerosol concentrations on both daily and seasonal time scales is primarily due to the scavenging of lead aerosol particles by rain rather than to changes in source regions. Our results suggest that the ratio between the total atmospheric deposition of Pb and the corresponding mean daily precipitation (mdp) rate is not constant. This ratio reaches a maximum during the Mediterranean summer. We attribute this difference to wet scavenging processes which wash a more loaded atmosphere during the dry season than during the wet season. The precipitation frequency (FP) is a major factor influencing seasonal variability of the total atmospheric deposition of lead over the western Mediterranean. An intermediate value of FP allows sufficient reloading of the atmosphere with long‐range transported Pb aerosol particles as well as efficient scavenging by precipitation events.

Correlation between petrol lead additive consumption and atmospheric lead concentrations in Perth, Western Australia

The impact of unleaded petrol (ULP), and the variation in lead (Pb) content of leaded petrol (LP), on air quality in Perth, Western Australia, has been assessed using correlations between atmospheric Pb concentrations and petrol Pb consumption figures for the period 1982–1987 during which ULP was introduced in 1985. The study underlines the importance of taking into account the variability in the Pb content of LP when predicting atmospheric lead concentrations from petrol consumption data.

Impact of lead phasedown on the environment with special reference to Saudi Arabia

Abstract This paper reviews the information available on lead pollution in Saudi Arabia. Comparison with some information from some countries is made. It was found that the atmospheric lead concentration in some cities in Saudi Arabia exceeds the European and American standards. The lead level in the blood of Saudi School children is reported. This is found to be within the international range. The Saudi plan for lead phasedown is stated. Alternatives for octane enhancement and the impact of lead phasedown on the Saudi environment are discussed. It is concluded that lead phasedown will significantly improve the environment's quality.

Lead levels of feral pigeons ( Columba livia) from Madrid (Spain)

Tissue lead data are presented for populations of feral pigeons ( Columba livia) from three locations in Madrid (Spain). The lead present in the lungs and digestive tract of pigeons increased progressively with traffic density and in parallel with atmospheric and ground lead values. The contribution of the respiratory route of Pb intake to the pigeons was about three times greater than the digestive route. The highet Pb values were found in bones. It is suggested that the pigeons gave a greatly magnified picture of lead pollution in cities than indicated by atmospheric lead concentrations.

Atmospheric distribution of particulate lead over the Atlantic Ocean from Europe to Antarctica

Concentrations of lead in aerosols over the Atlantic Ocean were measured between 50 °N and 70°S during different expedition legs of the German polar research ship FS Polarstern in 1984 and 1985. The Pb concentrations varied from 0.008 to 66 ng m −3. High Pb concentrations have been found near regions with high industrial activities. The highest values were detected near the west coast of Europe and in some coastal regions of South America. Measurements where Fe beside Pb was determined as a crustal element, show in their Pb/Fe ratio that anthropogenic and other non-crustal sources significantly influence the atmospheric lead concentration near the coast of West Africa (south of Dakar) and South America. The measured Pb/Fe ratios over the ocean between both continents are much lower, but still higher than the crustal Pb/Fe ratio. Very low Pb concentrations in the range of 0.1–3 ng m −3 were measured between the African and South American continents near the equator and around the South Shetland Islands near the Antarctic Peninsula. However, the lowest Pb concentrations of 8–25 pg m −3 were found in aerosols over the Ekström ice shelf in Antarctica, near the ice edge. The present study has resulted in one of the most extensive global distribution patterns of this important trace element so far. In addition, the analysis by isotope dilution mass spectrometry guarantees accurate results down to an atmospheric level of a few pg Pb m −3 if contamination is under control.

Review of data on eolian fluxes of industrial and natural lead to the lands and seas in remote regions on a global scale

During preindustrial times about half the lead in the troposphere came from soil dusts while the remainder came from volcanic gases. Today the proportion of this natural lead in the atmosphere is overwhelmed by industrial lead emitted from smelters and automobile exhausts. In the Antarctic tropospheric cell, atmospheric concentrations of industrial lead are five-fold greater than natural lead concentrations, while in urban atmospheres the proportions of industrial lead are more than 10 000-fold greater than those of natural lead. About 90% of industrial lead emissions to the global atmosphere are introduced into the Northern hemisphere westerlies from North America, Europe and Japan, with most of the remainder being introduced into the Southern hemisphere westerlies from Brazil, South Africa, Australia and New Zealand. This creates a north-south gradient in global atmospheric lead concentrations across meridional tropospheric circulation cells because their convergence barriers restrict latitudinal mixing. Atmospheric lead concentrations in a pole-to-pole strip across the central Pacific show a decline in lead within meridional cells on either side of the Northern westerlies. This hemispheric set contains higher lead concentrations on the whole than does the corresponding set of meridional cells in the Southern hemisphere, because of the isolating effect of the equatorial mixing barrier. In the Southern hemisphere the westerlies cell again contains higher lead concentrations than do adjacent meridional cells, with the Antarctic cell being the least lead polluted portion of the Earth's atmosphere. Tabulations of eolian input fluxes of lead from these atmospheric reservoirs to the Earth's surface for remote regions are given in this review, as well as methods for estimating the proportions of natural and industrial lead in soil dust, sea salt, volcanic sulfate and anthropogenic particles in air and rain.

Lead concentrations and source strength in the atmosphere of an urban site

A series of atmospheric lead concentration measurements in the Oviedo urban area have been carried out. A linear correlation between lead and large positive ion concentrations has been obtained ( r 2 = 0.88). From this correlation and by use of a box diffusion model, the lead source strength has been calculated. As an application, measurements of large positive ion concentrations can provide an easy method for lead monitoring in an urban site.

Environmental lead exposure of an urban Indian population

Environmental lead exposure of the Greater Bombay population has been estimated by measuring lead concentrations in air particulates, water, food and cigarette smoke. Atmospheric lead concentrations in different zones of the city varied between 82 and 605 ng m −3. The dietary intake of lead is estimated to be 245 μg day −1 and is calculated from the lead content in different food groups and the amount of that group consumed by an average resident of the city. The uptake by a non-smoker living in the city area is estimated to be 33 μg of lead per day, 75% of which comes from food, 15% from air and 10% from water. For a suburban resident 85% of the lead intake comes from food. The blood lead measurements and the contribution of atmospheric lead to the blood lead level are discussed.

Relationship between ambient lead concentrations and lead in gasoline in Rio de Janeiro, Brazil

Lead concentrations were determined in total suspended particulate matter (TSP) from August 1975 to April 1978, in two districts of Rio de Janeiro with different sources of airborne particulate matter. Correlation coefficients between lead content in gasoline and average atmospheric lead concentrations are calculated. Results show a clear effect in the atmosphere if there is a large increase in the lead content of consumed gasoline.

Lead pollution in Tokyo—The pigeon reflects its amelioration

To monitor lead pollution in the Tokyo metropolitan area, we checked the feral pigeon Columba livia var. blood lead levels and δ-aminolevulinic acid dehydratase activities (ALA-D) of the erythrocytes over the period from 1971 to 1980. The pigeons gave much more magnified pictures of lead pollution than atmospheric lead concentrations indicated, even after addition of tetraethyl lead to the regular gasoline was totally banned in 1975. Since the biological half-life of lead in the pigeon was determined to be relatively short, this was considered mainly due to their habit of ingesting gizzard stones polluted with lead. The amelioration of lead pollution, reflected in the pigeons in downtown Tokyo, was observed with a few years of lag time after the improvement of the atmospheric lead concentration was first noted.

Concentration of lead in the atmosphere and soil measured in the vicinity of a secondary lead smelter

Abstract A conventional survey of the total lead content of soils was undertaken in the vicinity of a secondary lead smelter in West Yorkshire, U.K. In addition, continuous monitoring of atmospheric lead concentrations and deposition rates was carried out at a site 300 m to the northwest of the source. While soil survey results adequately demonstrated the impact of the smelter on the immediate locality atmospheric lead data together with theoretical considerations indicated that current losses from the smelter are substantially less than the soil record would suggest.

Seasonal changes in the lead content of pasture grass growing near a motorway

The above-ground portion of perennial ryegrass ( Lolium perenne), in fields both bordering and distant from the M6 motorway in Cheshire (Great Britain), was sampled monthly during the period October 1977–October 1978. A 10-fold seasonal variation in lead level was found at all sites. The maximum level near the motorway (285 μg/g) was found during the ‘winter’ months, whilst the lowest level (15 μg/g) was found from May to August. It was concluded that the seasonal variation was a result of changes in the growth form of the plant. Other factors such as seasonal changes in atmospheric lead concentration and lead uptake from the soil may be of minor significance. It is believed that present levels of lead in pasture grass, both close to and distant from the motorway, present no toxic hazard to grazing animals, but it may be advisable to restrict the use of pasture bordering major roads during the period December–April.

Motor vehicle emissions and atmospheric lead concentrations in the los angeles area

This paper is directed to those concerned with the effect of changes in lead consumption by motor vehicles on atmospheric lead concentrations. Atmospheric lead concentrations in the Los Angeles area have been found to be dependent on lead consumption, meteorology, and source-receptor relationships. Mathematical relationships between these variables for selected Los Angeles area sites are derived. Los Angeles County experienced a 50% reduction in annual average atmospheric lead concentrations between 1971 and 1976, which was found to be due to a decrease in vehicular emissions of lead. Seasonal variations in lead concentration were found to be mainly a product of seasonal variations in weather. Projections of atmospheric lead concentrations for the next decade show a continued downtrend, based on regulation of fuel lead content and introduction of additional catalyst equipped vehicles. By the mid-1980's most locations in the Los Angeles area are expected to attain the California and federal ambient air quality standards for lead, 1.5 micrograms per cubic meter, based on a monthly average.

Seasonal trends in Denver atmospheric lead concentrations

During the period January 1972 to June 1975, monthly average atmospheric lead concentrations at five metropolitan Denver sampling sites displayed macima during winter months that coincided with minima in mixing heights. Monthly atmospheric lead inputs estimated on the basis of city-wide consumption of leaded gasoline showed a general downward trend with maxima during summer months. Atmospheric lead concentrations correlated well with the dispersion factor, the product of the mixing height and the mean wind speed. Monthly average atmospheric lead concentrations did not correlate with a simple linear proportion of monthly lead additive consumption, even when effects due to variability in the dispersion factor were statistically removed. Thus, the short-term variability in other parameters, including actual automotive lead emission factors and traffic patterns, masked the variability due to lead additive consumption during the study. However, this does not preclude the possibility that the linear rollback model may still apply to automotive lead over the long term of several years to decades. 32 references, tables.

Uptake of lead near roads in Egypt

A determination of the atmospheric lead concentration on different plants in various locations in Egypt was carried out using an Atomic Absorption Spectrophotometer. The lead deposits ranged from 1.35 ppm to 18.60 ppm. There was a positive correlation between lead content and the intensity of lead pollution.