Trace element levels in whole blood samples from residents of the city Badajoz, Spain.

Copper, lead, cadmium, and zinc were determined by anodic stripping voltammetry after sample digestion and potentiometric stripping analysis was used for Pb and Cd determination in original samples. Selenium was determined by cathodic stripping voltammetry or hydride generation AAS. Element levels found in the whole blood sample in a group of 82 people are for Cd: 0.98 +/- 0.94 ng/ml; for Pb: 46.7 +/- 28.6 ng/ml; for Cu: 1.07 +/- 0.12 micrograms/ml; for Zn: 6.95 +/- 1.08 micrograms/ml, and for Se: 116 +/- 25 ng/ml. Analytical data have been correlated to age, sex, smokers or non-smokers, drinking and food habits.     

Dental lead levels in residents from industrial and suburban areas of Kuwait

The present study describes lead concentrations in whole incisor teeth (non-carious) of 216 Kuwaiti resident's aged 3-74, collected from industrial and suburban areas of Kuwait. The mean concentration of lead in all age groups (3-74) showed a significant correlation between both the sexes. Statistical analysis showed a significant correlation between lead levels of males compared with industrial and suburban areas. A similar correlation was also noted in the case of females supporting that industrial residents were more exposed to lead levels than those in suburban areas. A further significant correlation was noted between males and females of industrial and suburban areas which showed that males accumulate more lead concentration than females. A significant correlation was not observed when each age group was compared with that of the respective sexes representing industrial and suburban areas. However, a significant correlation was noted when lead levels in each age group was compared with that of the other age groups except in age groups ranging 35-42. The mean lead levels of 216 teeth were in the range 2.21-2.50 micrograms/g which is less than the range indicated by other investigators in the recent past.     

Lead in human bones. Investigations on an occupationally non-exposed population in southern Bavaria (F.R.G.). I. Adults

The concentration of lead in three different bones (pelvic bone, cortical part of the mid-femur, petrous portion of the temporal bone) of 240 occupationally non-exposed adults who died between October 1983 and February 1985 was determined by electrothermal atomic absorption spectrometry. As far as sex, age and domicile (urban and rural) are concerned, a balanced distribution was achieved (for each age decade 10 urban females, 10 rural females, 10 urban males and 10 rural males). The predominantly cortical femur (geom. mean, 3.86 mg Pb/kg bone wet wt.) and temporal bones (5.59) showed higher Pb concentrations than the trabecular pelvic bone (1.65) (in each case n = 240). For each of the three types of bone, the mean lead content of the males (n = 120) was significantly higher than those of the females (n = 120): e.g. for pelvic bone by 38.3%, mid-femur by 51.3% and temporal bone by 24.8%. No statistically significant difference was obtained when comparing residents of Munich (population greater than 1 X 10(6] (n = 120) with people in the remaining parts of Southern Bavaria (n = 120). The Pb content of the temporal bone increased steadily with age. In contrast, in the mid-femur and the pelvic bone the Pb content reaches a plateau in middle age with a decrease at higher ages; this decline is more distinct for females. The mean lead body burden was calculated to be 41.4 +/- 24.2 mg for all males (n = 120) and 24.1 +/- 12.5 mg for all females (n = 120). We conclude that the lead burden, at least in the area investigated, has been reduced in the last decade, probably because of a reduction in the lead content of petrol.     

European isotopic signatures for lead in atmospheric aerosols: a source apportionment based upon 206Pb/207Pb ratios

To investigate the capability of the lead isotope signature technique to support a source apportionment study at a Continental scale, atmospheric particulate matter was collected at Cap Gris-Nez (Eastern Channel, northern France), over one year (1995-1996). Four days retrospective trajectories of air masses were available during each sampling experiment. Twenty-eight samples, for which the origin of aerosols was unambiguously determined, were selected for isotopic measurements. Considering the Enrichment Factors, EF(Crust) of lead and its size distribution, we show that lead is mostly from anthropogenic origin and mainly associated with [0.4 < diameter < 0.9 microm] particles. The extent to which various Continental sources influence the lead abundance in aerosols is exhibited by considering both the lead concentration and the origin of air masses. Lead concentration is higher by a factor of approximately seven, when air masses are derived from Continental Europe, by comparison with marine air masses. Taking into account these concentrations and the vertical movements of air masses, we compare the different isotopic compositions using a statistical non-parametric test (Kolmogorov-Smirnov). We produce evidence that, for most of the cases, air masses originating from Continental Europe exhibit a more radiogenic composition (1.134 < 206Pb/207Pb < 1.172) than air masses coming from the United Kingdom (1.106 < 206Pb/207Pb < 1.124). Generally, lead isotopic compositions in aerosols are clearly distinct from the gasoline signatures in European countries, strongly suggesting that automotive lead is no longer the major component of this metal in the air. Gasoline and industrial isotopic signatures could explain the origin of lead in our aerosol samples. A source apportionment based upon 206Pb/207Pb ratios, suggests that the difference between British (206Pb/207Pb = 1.122 +/- 0.038) and Continental (206Pb/207Pb = 1.155 +/- 0.022) signatures may be largely explained by differences in the petrol lead content of aerosols (23-62% in Great Britain vs. 10-36% in Continental Europe).     

The influence of subcutaneously administered lead(II) acetate on the concentrations of copper, iron, and zinc in the blood, kidney, liver, and spleen of rats

The concentrations of copper, iron, lead, and zinc in the blood, kidney, liver and spleen were determined before and after subcutaneous administration of lead(II) acetate (100 mg Pb kg-1 body weight) to male albino Wistar rats. The control rats had the following concentrations (microgram g-1 dry weight) of Cu, Fe, Pb and Zn: blood, 4.5, 3200, 2.1, 182; kidney, 36, 585, 120, 92; liver, 11.1, 720, 14.3, 124; spleen, 4.5, 420, 7.0, 76. After administration of lead, rats were sacrificed after 12, 24, 48, 72 and 96 h. The Pb concentration in the blood remained constant for the first 24 h at the level of the control group (2.1 micrograms g-1) and had decreased to half that level at 96 h. The lead concentrations peaked in the organs at 110-142% of those in the control group and had decreased at 96 h to levels considerably below those in the control group. The concentrations of Cu, Fe and Zn increased in the three organs to values 117-161% found for the control group. At 96 h the concentrations of Cu, Fe and Zn in the spleen had returned to levels of the control group; the concentrations in the liver were 112-153%, and in the blood 89-93% of those of the control group. In the kidney the iron (110%) and the zinc (126%) concentrations at 96 h were higher than the control values, whereas the copper concentration was the same as the control value. The concentrations in the blood were least affected. The most drastic changes were observed in the liver.(ABSTRACT TRUNCATED AT 250 WORDS)     

Assessment of metal pollution in Onsan Bay, Korea using Asian periwinkle Littorina brevicula as a biomonitor.

Cadmium (Cd), lead (Pb), copper (Cu) and zinc (Zn) concentrations in the marine gastropod, Littorina brevicula Philippi, were determined to assess the metal pollution in Onsan Bay, Korea. Samples of L. brevicula employed as a biomonitor and seawater were collected from 12 to 20 stations of Onsan Bay in November 1997, respectively. Dissolved metal concentrations in surface seawater were highest at the station near Onsan Non-ferrous Industrial Complex: 1.15 micrograms l-1 for Cd, 2.49 micrograms l-1 for Pb, 3.75 micrograms l-1 for Cu and 23.98 micrograms l-1 for Zn. These values were 1-2 orders higher than those shown at outer regions of the Bay. Metal concentrations in the soft body of periwinkles were highly variable at different sampling locations: 0.48-27.11 micrograms g-1 for Cd, 1.41-24.91 micrograms g-1 for Pb, 57-664 micrograms g-1 for Cu and 83-246 micrograms g-1 for Zn. The values from stations near the industrial complex were higher than those expected from relationships between body sizes and metal body burdens in periwinkles collected from the whole Korean coast. Spatial distribution of metal concentrations in the periwinkle and seawater indicated that Onsan industrial complex near the Bay is the input source of these metals. Especially, Cd and Pb concentrations in the periwinkle and seawater were distinctly decreased with distance from the Onsan industrial complex. Non-essential metals such as Cd and Pb in the periwinkle showed a strong correlation with dissolved metal concentrations in seawater. Conversely, essential Cu and Zn in the periwinkle were hardly explained by those in seawater, except at the most contaminated sites.     

Non-occupational lead and cadmium exposure of adult women in Bangkok, Thailand

This survey was conducted to examine the extent of the exposure of Bangkok citizens to lead (Pb) and cadmium (Cd), and to evaluate the role of rice as the source of these heavy metals. In practice, 52 non-smoking adult women in an institution in the vicinity of Bangkok, volunteered to offer blood, spot urine, boiled rice and 24-h total food duplicate samples. Samples were wet-ashed, and then analyzed for Pb and Cd by ICP-MS. Geometric means for the levels in blood (Pb-B and Cd-B) and urine (Pb-U and Cd-U as corrected for creatinine concentration), and also for dietary intake (Pb-F and Cd-F) were 32.3 micrograms/l for Pb-B, 0.41 microgram/l for Cd-B, 2.06 micrograms/g creatinine for Pb-U, 1.40 micrograms/g creatinine for Cd-U, 15.1 micrograms/day for Pb-F and 7.1 micrograms/day for Cd-F. Rice contributed 30% and 4% of dietary Cd and Pb burden, respectively. When compared with the counterpart values obtained in four neighboring cities in southeast Asia (i.e. Nanning, Tainan, Manila, and Kuala Lumpur), dietary Pb burden of the women in Bangkok was middle in the order among the values for the five cities. Pb level in the blood was the lowest of the levels among the five cities and Pb in urine was also among the low group. This apparent discrepancy in the order between Pb-B (i.e. the fifth) and Pb-F (the third) might be attributable to recent reduction of Pb levels in the atmosphere in Bangkok. Regarding Cd exposure, Cd levels in blood and urine as well as dietary Cd burden of Bangkok women were either the lowest or the next lowest among those in the five cities.     

Lead isotopes and lead shot ingestion in the globally threatened marbled teal (Marmaronetta angustirostris) and white-headed duck (Oxyura leucocephala)

Lead isotope ratios ((206)Pb/(207)Pb and (208)Pb/(207)Pb) and concentrations in the livers and bones of marbled teal and white-headed duck found dead or moribund were determined in order to establish the main lead source in these waterfowl species. Lead concentrations in bone (dry weight) and liver (wet weight) were found to be very high in many of the white-headed ducks (bone: geometric mean=88.9 ppm, maximum=419 ppm; liver: geometric mean=16.8 ppm, maximum=57.0 ppm). Some of the marbled teal had high lead levels in the bones but liver lead levels were all low (bone: geometric mean=6.13 ppm, maximum=112 ppm; liver: geometric mean=0.581 ppm, maximum=4.77 ppm). Ingested lead shot were found in 71% of the white-headed duck and 20% of the marbled teal. The (206)Pb/(207)Pb ratio in livers and bones of white-headed ducks and marbled teals showed no significant differences compared to the ratios obtained from lead shot. The (206)Pb/(207)Pb ratio in bones of marbled teal ducklings with the highest lead concentrations tended to resemble the ratios of lead shot, which supports our hypothesis that the lead was derived from the hens. We also found that the lead ratios of lead shot and lead ratios described for soils in the area overlapped, but also that the isotopic ratio (206)Pb/(207)Pb in lead shot used in Spain has a narrow range compared with those used in North America. The principal source of lead in many of these birds was, however, most likely lead shot, as supported by the similar isotopic ratios, high lead concentrations in tissues and evidence of ingested shot.     

Trace metals in the bones of scaup ducks (Aythya marila L.) wintering in Gdańsk Bay, Baltic Sea, 1982-83 and 1983-84

The concentrations of Fe, Zn, Mn, Cu, Pb, Cd, Co, Ni, Cr and Ag in 88 samples of various bones and five samples of trachea prepared from scaup ducks (Aythya marila L.) have been determined. With the exception of lead, no significant sex-related differences were observed for the concentration of metals. However, there were significant differences in the concentrations of most metals for different bones.     

Heavy metals in human and animal bones from ancient and contemporary France

The concentrations of Cd, Pb, Zn, Ba, Mg and Ca have been determined in 180 human bones from the last five millenia, and in 22 contemporary and 20000-50000-year-old animal bones. The original concentrations of Cd and Zn in the ancient human bones were not changed by fossilization processes, whereas Pb and Mg tended to migrate out of the bones, and Ba and Ca concentrations increased with the age of the bones. The distribution of metals in the structure of both the ancient and contemporary bones is not uniform, and neglecting this may render it difficult to compare results obtained from different studies. In Europe and Peru in the late Middle Ages the concentration of Pb in human bones increased by one order of magnitude. The high level of Pb persisted in Europe for several centuries and only recently decreased by an order of magnitude. The concentration of Cd has increased in human bones in the 20th century, to about ten times above the pre-industrial level. The concentration of Pb in contemporary cow bones from France is below analytical detection limits, probably due to competition of Pb with Ca and P which are added to cow fodder as mineral additives.     

A comparative study of manganese and lead levels in human umbilical cords and maternal blood from two urban centers exposed to different gasoline additives

Manganese (Mn) and lead (Pb) are two neurotoxic chemicals and experimental evidence suggests that they can cross the placental barrier. Tetraethyl lead was still in use as an antiknock agent in Paris during the sampling period of the study, while it has been replaced by methylcyclopentadienyl manganese tricarbonyl (MMT) in Canada since 1977. By 1990, MMT was in 100% of gasoline in Canada. In a study of 160 pairs of mothers-neonates in Montreal and 206 pairs in Paris, we compared levels of Mn and Pb in the umbilical cord and in maternal blood. Neonates and mothers had significantly higher Pb levels in Paris where lead additives were still used in gasoline. Geometric mean maternal blood Pb levels were 5.4 microg/dl compared to 2.1 microg/dl in Montreal and cord blood Pb levels were 3.2 microg/dl in Parisian mothers compared to 1.7 microg/dl in Montreal. The prevalence of Paris Pb values superior to the 95th percentile of the Montreal distribution was highly elevated in all media studied. The prevalence of high Mn levels in umbilical cord blood was also significantly higher in Montreal. Surveillance programs are important to limit Pb overexposure and associated neurological effects in neonates where tetraethyl Pb is still in use as a gasoline additive. Since Mn is an essential element and dietary Mn intake may differ between Montreal and Paris, the difference observed with regard to high Mn values between Montreal and Paris cannot, at this time, be attributed to MMT in Montreal's gasoline. Further studies are needed to infer an association between Mn emissions from MMT and prenatal exposure to Mn.     

Serum and urine selenium concentrations as indicators of body status in patients with diabetes mellitus.

Serum and urine selenium levels were determined in patients with diabetes by hydride generation atomic absorption spectrometry. Mean serum selenium concentrations measured in patients with diabetes mellitus (64.9 +/- 22.8 micrograms/l) were significantly lower than those determined in the control group (74.9 +/- 27.3 micrograms/l) (P < 0.05). Mean serum selenium concentrations were not significantly different between the two groups of diabetic patients considered (P > 0.05). Mean urine selenium concentration in diabetic patients (18.8 +/- 10.7 micrograms/l) were not significantly different from those measured in the control group (20.2 +/- 10.1 micrograms/l) (P < 0.05). No significant differences in serum and urine selenium levels were found if related to sex of patients (P > 0.05). Application of linear regression analysis to serum and urine selenium levels and patients' age showed a non-statistically significant correlation (P > 0.05). Given the marked overlap between the two ranges of the populations, the predictive values of serum selenium in diabetic patients are low.     

Blood lead and its effect on Cd, Cu, Zn, Fe and hemoglobin levels of children

The levels of heavy metals, such as Pb, Cd, Cu, Zn and Fe, in whole blood samples of Mumbai and Hyderabad children have been determined. In the present study, 576 blood samples of children (3-6 years old) were collected during 1996-1998 and analyzed for heavy metal contents by anodic stripping voltammetry and atomic absorption spectrometry. The geometric mean concentrations of Pb, Cd, Cu and Zn in blood of Mumbai children were 8.0, 0.10, 86.5 and 398.9 microg dl(-1), while those for Hyderabad children were 13.3, 0.13, 100.6 and 483.4 microg dl(-1) respectively. The geometric mean concentrations of Fe in the blood of Mumbai and Hyderabad children were 21.9 and 34.5 mg dl(-1), respectively. Of the Mumbai children, 61.8% were found to have a blood lead concentration lcss than 10 microg dl(-1), while the corresponding proportion of Hyderabad children was 27.4%. Higher concentrations of Pb in the children's blood were observed at high traffic areas in both cities. A decreasing trend in the hemoglobin content with increasing blood lead levels was observed for Mumbai children. A good negative correlation (-0.61) between the blood lead and iron has been observed for Mumbai children The hemoglobin content of 85% of the study population was found to vary between 8 and 14 g%.     

The isotopic composition of lead in man and the environment in Finland 1966-1987: isotope ratios of lead as indicators of pollutant source.

The isotopic composition of lead was determined in samples collected between 1966 and 1987, mainly from the Helsinki area, in emission sources (gasoline, incinerator and lead smelter emissions, coal), air, in samples representing long-term deposition (lichen, soil, lake sediments), and in human tissue. Isotope ratios were determined by thermal ionization mass spectrometry after chemical separation of lead by anion exchange and cathodic electrodeposition. The origin of lead in man and the environment in the Helsinki area was evaluated by using the differences in the measured isotope ratios as an indicator. The mean of the ratio in gasoline (206Pb/207Pb 1.124 +/- 0.026) and the ratios in other emission sources in Helsinki (1.149-1.226) were significantly different. However, the wide range of isotope ratios in gasoline (1.063-1.173) reduced the accuracy when assessing the contribution of the different sources. Lead in air samples from Helsinki (1.123 +/- 0.013) could be attributed to gasoline, as could lead in soil near a highway (1.136 +/- 0.003). By contrast, isotope ratios measured in lichen (1.148 +/- 0.006) indicated considerable amounts of lead from sources with higher 206Pb abundances, evidently industrial sources. The isotope ratios in human liver, lung, and bone from individuals dying between 1976-79 (206Pb/207Pb ratio 1.142 +/- 0.015, 1.151 +/- 0.011, and 1.156 +/- 0.013, respectively) reflect the large lead emissions from the incinerators and lead smelters in the Helsinki area in the 1960s and 1970s. In lake sediment cores a correlation was found between the isotope ratios, lead concentration, and depth. The nonanthropogenic lead of high isotope ratios from bedrock was the major component at depths dated older than 100 years. At the surface of the sediment atmospheric lead prevailed, with ratios similar to those of gasoline, air samples and lichen. In the post-1900 layers, anthropogenic lead made up about 40-95% of the total sedimentary lead.     

A lead isotopic assessment of tree bark as a biomonitor of contemporary atmospheric lead

The outermost bark layer of trees, predominantly Scots pine (Pinus sylvestris), was sampled at 82 non-urban locations from six arbitrarily designated areas (Northwest, Northeast, Central Highlands, Central and East, Central and Southwest, Southeast), throughout Scotland during 2002-2003 and analysed for lead concentration and stable lead isotopes by flame atomic absorption spectrometry (AAS) and inductively coupled plasma-mass spectrometry (ICP-MS), respectively. The mean lead concentration and mean (206)Pb/(207)Pb ratio (+/-1 standard deviation, SD) for bark samples from the areas were as follows: Northwest (8.0 mg kg(-1), 1.121+/-0.014, n=17), Northeast (8.9 mg kg(-1), 1.117+/-0.012, n=12), Central Highlands (11.3 mg kg(-1), 1.130+/-0.010, n=11), Central and East (35.3 mg kg(-1), 1.120+/-0.007, n=10), Central and Southwest (20.6 mg kg(-1), 1.125+/-0.018, n=22) and Southeast (34.4 mg kg(-1), 1.120+/-0.005, n=10), with an overall mean lead concentration of 18.5 mg kg(-1) (range 0.6-146 mg kg(-1), median 8.4 mg kg(-1)) and an overall mean (206)Pb/(207)Pb ratio of 1.122+/-0.014 (range 1.089-1.168, median 1.122). The overall mean (206)Pb/(207)Pb ratio for bark was therefore significantly lower (p<0.01, t test) than the mean atmospheric (206)Pb/(207)Pb ratio of 1.154+/-0.006 (range 1.144-1.167, n=50) and 1.154+/-0.010 (range 1.134-1.171, n=26) as determined in rainwater collected routinely at Glensaugh, Central Highlands, during 2002 and 2003, respectively. The bark (206)Pb/(207)Pb values, 90% of which lay between 1.10 and 1.14, were more akin to those recorded for the atmosphere (via rainwater, atmospheric particulates, moss, etc.) at various locations throughout Scotland during the 1990s, a decade over which the use of leaded petrol (mean (206)Pb/(207)Pb ratio=1.076+/-0.011) declined markedly before its complete withdrawal in 2000. This strongly suggests that the lead content and isotopic composition of tree bark from Scots pine, which reputedly sheds its outer layers every couple of years or so, reflect exposure to atmospherically deposited lead (in the atmosphere or soil) over a much longer time period than just the previous 2-3 years of exposure to contemporary atmospheric lead. The possible influence of soil lead upon tree bark through external attachment was not observed in a comparative sub-set study of 27 paired bark (mean (206)Pb/(207)Pb ratio=1.122+/-0.016) and surface (0-2 cm) soil (mean (206)Pb/(207)Pb ratio=1.145+/-0.022) samples, in only six cases (i.e. 22%) of which did the corresponding (206)Pb/(207)Pb ratios agree within +/-2 SD. Likewise, bark (206)Pb/(207)Pb values exhibited no discernible trend with distance from the nearest road, with similar average values for 0-20 m (1.123+/-0.015, n=34) and 20-700 m (1.122+/-0.012, n=48), although the corresponding mean (and median) lead concentration of 23.5 (10) mg kg(-1) vs. 14.9 (7.5) mg kg(-1) was slightly higher for the former. The influence of airborne dusts from waste deposits related to former mining/smelting of Wanlockhead/Leadhills lead ores ((206)Pb/(207)Pb=1.170+/-0.003) could be seen, however, in the sycamore bark lead concentrations of up to 3050 mg kg(-1) and (206)Pb/(207)Pb ratios (1.168-1.171) observed at a distance of 0.5 km away.     

Assessment of pollution aerosols sources above the Straits of Dover using lead isotope geochemistry.

We assess the capability of lead isotopes to study the transport of pollution aerosols above the Straits of Dover by collecting atmospheric aerosols above the Eastern Channel and the Southern Bight of the North Sea. During the same period, we characterized the lead isotopic signature of the main industrial sources on the French coast near the Straits of Dover. Urban and automobile-derived aerosols were also collected. Due to the phasing out of lead in gasoline, the urban isotopic composition (206Pb/207Pb = 1.158 +/- 0.003) has become more radiogenic, although it is highly variable. On a regional scale, major industrial emissions have a well-defined isotopic composition (1.13 < 206Pb/207Pb < 1.22), more radiogenic than the petrol-lead signature (1.06 < 206Pb/207Pb < 1.12). These results together with those measured near the main coastal highway show that the automobile source has become a minor component of particulate lead in air. On a local scale, Dunkerque, the most urbanized and industrialized area along the Straits of Dover, may transiently control elevated lead concentrations. Except for the occurrence of local and regional range transport episodes, lead concentrations in the Straits of Dover can be related to remote or semi-remote pollution source emissions. Combining air mass retrospective trajectories and related lead abundances and isotopic compositions, it can be shown that lead aerosols originating from eastern Europe have an isotopic signature (1.145 < 206Pb/207Pb < 1.169) different from the isotopic composition of west-European lead aerosols (1.111 < 206Pb/207Pb < 1.142). The influence of remote North American sources is suggested, with caution, due to uncertainties in meteorological calculations.     

Daily intake of heavy metals by infants through milk and milk products

Concentrations of the essential elements Zn and Cu and potentially toxic elements Pb and Cd in different milk samples and baby food materials were measured, primarily to assess whether the intakes comply with recommended desired levels for essential and permissible levels for toxic elements. The geometric mean concentrations of Pb, Cd, Cu and Zn in different types of milk were found to vary from 1.70 to 3.35, 0.07 to 0.10, 43.2 to 195 and 1772 to 4230 micrograms/l, while the same in different baby foods had values from 39.5 to 77.7, 0.45 to 17.7, 1106.3 to 3157.3 and 9367 to 34,592 micrograms/kg, respectively. The concentration of Cd was found to be very low (0.1 microgram/l) and fairly constant in all types of milk. The lead content in cow milk was observed to be lowest even in comparison with breast milk. Concentrations of all these metals are approximately one order of magnitude higher in baby food products than those observed in different types of milk owing to higher fat content. The infant baby food Amul Spray contains low concentrations of toxic (Pb and Cd) and high concentrations of essential (Cu and Zn) elements. The daily intakes of Pb, Cd, Cu and Zn by infants through milk and baby foods marketed in Mumbai city have also been estimated. The daily intakes of Pb (1.1 micrograms/kg) and Cd (0.01 microgram/kg) for infants through baby foods are well below the recommended tolerable levels of 3.57 micrograms/kg and 0.8-1.0 microgram/kg, respectively. Similarly the daily intake levels of essential elements are also significantly lower than the recommended desirable levels of 3-5 mg and 0.5-1.0 mg for Zn and Cu, respectively. Milk from an Indian mother also does not provide adequate levels of essential elements to the infants and children.     

Analysis of lead body burden in Turkey.

Here we report the results of pilot screening for the environmental lead contamination in Turkey. Lead blood concentrations were determined in 342 subjects from 17 cities. The mean lead blood concentration, 3.65 +/- 1.66 micrograms/dl, is much lower than the values reported previously. People smoking tobacco and driving motor vehicles had elevated concentrations of lead in blood. There was also a moderate relationship between the urban population size and the lead in blood values, but no differences were observed, that could be related to distinct geographical locations. Motor traffic was assumed to be the main source of lead pollution in the urban environment in Turkey, and the low lead blood levels were linked to the reduction of lead additives in gasoline, in 1989. Although at present, the environmental lead contamination does not pose a considerable threat to public health, in the near future, when the motorization rate and gasoline consumption will possibly double or triple, the lead content in gasoline might need to be further reduced.     

Heavy metals in maternal and cord blood

Heavy metal concentrations have been determined in maternal and cord blood samples collected from mothers in the age group 20-25 years with full-term neonates (37-40 weeks). The concentrations of Pb, Cd, Cu and Zn were found to be low in cord blood as compared to mother's blood and the ratio between cord blood and maternal blood for the respective elements was found to be approximately 0.80, 0.86, 0.47 and 0.40. On the other hand, the concentrations of Fe and Mg in the mother's blood were found to be lower than those in the cord blood. Prenatal exposure to lead in Mumbai, though low (5.1 microg/dl), is approximately 2-3 times higher than that observed in Canada or Italy. A strong correlation (r = 0.79) between the maternal and cord blood lead levels has been observed during the present study.     

Lead and cadmium in human teeth from Jordan by atomic absorption spectrometry: Some factors influencing their concentrations

The aim of this study was to measure the concentrations of lead (Pb) and cadmium (Cd) in human teeth and to investigate the affecting factors. Teeth samples (n = 268) were collected from people living in different cities in Jordan including Amman, Zarqa, Al-Mafraq and Irbid and analyzed for Pb and Cd using atomic absorption spectrometry (AAS). A questionnaire was used to gather information on each person, such as age, sex, place where the patient lives, smoking, presence of amalgam fillings inside the mouth, and whether the patient uses toothpaste or not. The mean concentrations of Pb and Cd were 28.91 microg/g and 0.44 microg/g, respectively. The results indicate that there is a clear relation between Pb and Cd concentrations and the presence of amalgam fillings, smoking, and place of living. Pb was sex-dependent, whereas Cd was not. Our results show that Pb and Cd concentrations in samples obtained from Al-Mafraq and Irbid are higher than those obtained from Amman and Zarqa. Pb was highest in Mafraq, whereas Cd was highest in Irbid. The Pb and Cd concentrations in teeth from smokers (means: Pb = 31.89 microg/g, Cd = 0.49 microg/g) were significantly higher than those from nonsmokers (means: Pb = 24.07 microg/g, Cd = 0.37 microg/g). Pb and Cd concentrations in teeth of patients with amalgam fillings (means: Pb = 31.02 microg/g and Cd = 0.52 microg/g) were significantly higher than those from patients without amalgam fillings (means: Pb = 26.87 microg/g and Cd = 0.41 microg/g). Our results show that brushing the teeth daily with toothpaste does not significantly decrease the concentration of both Pb and Cd. The mean concentrations of Pb and Cd do not vary significantly between the ages 20-30, 31-40, and 41-50, but both increased rapidly at age 51-60.