Lead poisoning in swans in Japan

We investigated the occurrence, source and exposure time of lead poisoning in whooper swans (Cygnus cygnus cygnus) and Bewick's swans (Cygnus columbianus bewickii) in Japan during the winters of 1984-1987. Concentrations of lead in various tissues and physiological evidence of lead shot in some birds indicated that lead shotgun pellets were the source of lead, and exposure occurred after the birds arrived in Japan. Mortality probably occurred within 30 days after exposure to, and retention of, lead shot in the gizzard.     

Haematological parameters as predictors of blood lead and indicators of lead poisoning in the black duck (Anas rubripes)

The validity of various haematological parameters as indicators of blood lead concentration and lead poisoning in the black duck (Anas rubripes) is discussed. Elevated (> 40 microg dl(-1)) blood lead (PbB) levels were recorded in 41% of the 229 wild birds examined. No correlation was found between PbB concentration and haematocrit. Zinc protoporphyrin (ZPP) was positively correlated with PbB. Haemoglobin, delta-aminolevulinic acid dehydratase (ALA-d) activity and non-activated/activated ALA-d ratios were negatively correlated with PbB. The minimum PbB levels at which these parameters were affected varied greatly. ZPP and haemoglobin were relatively insensitive to PbB concentrations; whilst ALA-d activity and ALA-d ratio were influenced by PbB concentrations of < 5 microg dl(-1). Log(10) ALA-d ratio was more strongly correlated with PbB (r = -0.953) than log(10) ALA-d activity (r = -0.914) and the predictive validity (% false -ve and +ve predictions) of the ratio method was higher. The high individual variability in ALA-d activities at low PbB levels was greatly reduced by the use of the ALA-d ratio method. The ALA-d ratio method proved the most efficient for screening black duck for lead poisoning in the field.     

Blood lead levels among populations differentially exposed to vehicular exhaust in Rohtak, India

In the absence of local industrial sources of lead, leaded gasoline has been suggested as the major source of lead in the urban atmosphere of Rohtak town, situated near Delhi metropolitan city and with a high vehicular density. Blood lead levels were measured in 42 male volunteers from within the Rohtak area with varying degrees of exposure to vehicular exhaust. The occupationally exposed group with a daily exposure of 10-12 h in automobile workshops was found to have the highest levels of blood lead (mean value 21.26 microg dl(-1)) followed by roadside population (mean value 14.91 microg/dl(-1)). This group of people had a daily exposure of 8-10 h in their business establishments, situated at a distance of less than 5 to about 10 ft (< 1.5-c. 3.0 m) from the road with an average traffic density of 8000 vehicles day(-1). Urban residents were found to have higher blood lead levels (mean value 9.85 microg/dl(-1)) than the rural ones (mean value 3.34 microg/dl(-1)). The values were found to increase correspondingly with the increase in age and smoking habits within the particular categories of volunteers. The levels found in the present study are comparable to those reported from other major cities of India, but well within the tolerable limits as recommended by the European Economic Community.     

Environmental lead pollution threatens the children living in the Pearl River Delta region, China

Introduction and purpose

The objective of this study is to determine children??s blood lead levels and identify sources of lead exposure. Childhood lead exposure constitutes a major pediatric health problem today in China. A blood lead screening survey program for children in the age group of 2?C12?years residing in Pearl River Delta region, south of China, was carried out from Dec 2007 to Jan 2008.

Methods

Blood lead levels and lead isotope ratios of a total of 761 participants were assessed by inductively coupled plasma mass spectroscopy. Measurements of urban environmental samples for source identification of children lead exposure were also performed.

Results and conclusions

The geometric mean value of the children??s blood lead levels was 57.05???g/L, and 9.6% of them were higher than 100???g/L. The blood lead levels were still much higher than those in developed countries. Based on the data of environmental lead source inventories, lead isotopic tracing revealed that there is about 6.7% past used gasoline Pb embedded in Shenzhen residential dust and about 15.6% in Guangzhou dust, respectively.     

Accumulation in and effects of lead and cadmium on waterfowl and passerines in northern Idaho

Waterfowl and passerines in northern Idaho in 1987 had high levels of lead in their blood and tissues that originated primarily from mining and smelting activities. Four Canada geese (Branta canadensis) and one common goldeneye (Bucephala clangula) found dead contained 8 to 38 microg/g (wet mass) of lead in their livers. These levels exceed the lower lethal limit of 5 microg/g in experimental birds. Two of the Canada geese (one each from the contaminated and reference areas) died with ingested lead shotgun pellets (shot) in their gizzards, whereas the other three birds from the contaminated area contained no ingested shot and evidently died from ingesting environmental lead in sediment or biota. Lead burdens in most American robins (Turdus migratorius) and mallards (Anas platyrhynchos) were high, whereas those in tree swallows (Tachycineta bicolor) were slightly elevated. Lead accumulated to potentially hazardous levels in blood and tissues of some nestling robins (maxima of 0.87 microg/g in blood and 5.6 microg/g in liver) and mallards (maxima of 10.2 microg/g in blood and 2.8 microg/g in liver). In mallards, lead levels and associated physiological characteristics of blood were significantly different in juveniles (HY) versus adults (AHY). Activity of delta-aminolevulinic acid dehydratase (ALAD) was about 87 to 95% lower than values for control birds in experimental studies. Activity of ALAD was significantly inversely correlated with blood lead levels. Cadmium was detected in kidneys of most birds, but even the maximum concentration of 7.5 microg/g in an AHY mallard was below known harmful levels.     

Lead poisoning of passerines at a trap and skeet range

Our objective was to determine if ground foraging passerines in a woodland surrounding a trap and skeet range were subject to lead poisoning. Lead availability to birds was determined by shot counts and soil and earthworm analysis. Avian exposure to lead was identified by measuring free-erythrocyte protoporphyrin levels in blood and lead in tissues of three passerine species. Results showed that most shot were found in the top 3 cm of soil. Lead measurements ranged from 110 to 27,000 ppm (dry wt) in soil and were 660 and 840 ppm in earthworms. Sparrows held in an aviary at the range (p=0.02) and free-flying juncos (p=0.0005) mist-netted at the range displayed significantly higher protoporphyrin levels than those at an uncontaminated site. Sparrow and cowbird carcasses from the aviary carried 37 and 39 ppm lead (dry wt), respectively, whereas a junco liver contained 9.3 ppm lead.     

Exposure of migrant bald eagles to lead in prairie Canada

The prevalence of elevated exposure to lead was assessed in a migrant population of bald eagles (Haliaeetus leucocephalus) at a waterfowl staging area in the southern portion of the Canadian prairies, from September to November, 1992-1995. Of 103 eagles, 8% exhibited blood lead (PbB) concentrations suggestive of elevated exposure to lead (> or = 0.200 microgram ml-1 wet wt.). PbB concentrations in eagles from the study area ranged from < 0.01 to 0.585 microgram ml-1, while those of nestling eagles from a reference site indicated normal or background exposure (< 0.01 microgram ml-1). No differences in the prevalence of elevated exposure were detected among genders or age classes (0.5- and > or = 1.5-year-old birds) (P > 0.05). The prevalence of elevated exposure was significantly greater in November than in October (21.7 vs. 3.8%) (all years: chi 2Y = 5.75, P = 0.017). Eagles with shotshell pellets in the digestive tract did not have accompanying high PbB concentrations. The prevalence of elevated lead exposure in this study was low in comparison to other areas in North America. Potential biases in the trapping technique as they relate to interpreting the results are addressed.     

Role of manganese oxides in the exposure of mute swans (Cygnus olor) to Pb and other elements in the Chesapeake Bay, USA

The aims of this study are to estimate exposure of waterfowl to elements in contaminated sediments in the Chesapeake Bay and to consider the potential role of Mn in influencing bioavailability and exposure. Metal concentrations were measured in livers and digesta taken from mute swans living on the Aberdeen Proving Ground, whose sediment had elevated concentrations of Cu, S, Se, Zn, As, Co, Cr, Hg and Pb. Concentrations of only the first four of these elements were elevated in swan digesta. None of the concentrations detected in the digesta or livers of the swans was considered toxic, although the concentrations of Cu and Se were high compared to concentrations of these elements reported in other waterfowl. Lead was found to be scavenged by Mn and Fe oxides from the water and deposited on the surface of vegetation at a reference site. Under some environmental chemical conditions, this is an important route of exposure to Pb in waterfowl, not previously recognized.     

Lead exposure and biological effects in pied flycatchers (Ficedula hypoleuca) before and after the closure of a lead mine in northern Sweden

Mining activities affect the surrounding environment by increasing exposure to metals. In this study, metal accumulation and its effects on reproduction and health of pied flycatcher (Ficedula hypoleuca) nestlings were monitored before and up to five years after a lead mine and enrichment plant closed down. The lead concentration in moss, nestling blood, liver and feces all indicated decreased lead exposure by at least 31% after closure, although only blood lead decreased significantly. Although the birds responded fairly well to the changed atmospheric deposition (based on moss samples), concentrations were still higher compared with birds in a reference area, and breeding was affected at the mine (smaller clutches and higher mortality). Surviving nestlings suffered from lower hemoglobin levels, mean cell hemoglobin concentrations and inhibited δ-aminolevulinic acid dehydratase activity. Lead poisoning contributed to poor health and adverse reproductive effects, but other factors (e.g. increased parasitic load) probably also affected the birds.     

Lead shot from hunting as a source of lead in human blood

This study investigates the relationship between the intake of birds hunted with lead shot and the lead concentration in human blood. Fifty adult men from Nuuk, Greenland took part in the study. From September 2003 to June 2004 they regularly gave blood samples and recorded how many birds they ate. We found a clear relationship between the number of bird meals and blood lead and also a clear seasonal variation. The concentration was highest in mid-winter when bird consumption is at its highest. Blood lead was low (15 microg/L, mean concentration) among the participants reporting not eating birds. Among those reporting to eat birds regularly, blood lead was significantly higher, up to 128 microg/L (mean concentration). Concentrations depended on the frequency of bird meals: the more the bird meals, the higher the resulting blood lead. This clear relationship points to lead shot as the dominating lead source to people in Greenland.     

Effects of lead and cadmium exposure from electronic waste on child physical growth

Many studies indicate that lead (Pb) and cadmium (Cd) exposure may alter bone development through both direct and indirect mechanisms, increasing the risk of osteoporosis later in life. The aim of this study was to investigate the association between Pb and Cd exposure, physical growth, and bone and calcium metabolism in children of an electronic waste (e-waste) processing area. We recruited 246 children (3–8 years) in a kindergarten located in Guiyu, China. Blood lead levels (BLLs) and blood cadmium levels (BCLs) of recruited children were measured as biomarkers for exposure. Serum calcium, osteocalcin, bone alkaline phosphatase, and urinary deoxypyridinoline were used as biomarkers for bone and calcium metabolism. Physical indexes such as height, weight, and head and chest circumference were also measured. The mean values of BLLs and BCLs obtained were 7.30 μg/dL and 0.69 μg/L, respectively. The average of BCLs increased with age. In multiple linear regression analysis, BLLs were negatively correlated with both height and weight, and positively correlated with bone resorption biomarkers. Neither bone nor calcium metabolic biomarkers showed significant correlation with cadmium. Childhood lead exposure affected both physical development and increased bone resorption of children in Guiyu. Primitive e-waste recycling may threaten the health of children with elevated BLL which may eventually cause adult osteoporosis.     

ALAD genotypes and blood lead levels of neonates and children from e-waste exposure in Guiyu,China

Extensive e-waste recycling activity in Guiyu, China, has been conducted using primitive techniques for the last 20 years, resulting in serious heavy metal environmental contamination. A polymorphic variant of the δ-aminolevulinic acid dehydratase (ALAD) gene has been found to influence lead uptake and, thus, may influence an individual’s susceptibility to lead toxicity. We therefore explored whether the ALAD gene polymorphism affects blood lead levels of newborns and children in Guiyu. A total of 273 newborns and 504 children, and a combination of 2004/2005 and 2006 independent recruitments were used for this study. Umbilical cord blood from newborns (Guiyu/exposed group 189 vs. Chaonan/reference group 84) and venous blood from children (exposed group, 319 vs. Chendian/reference group 185) were collected. Blood lead levels (BLLs) were measured via graphite furnace atomic absorption spectrometry (GFAAS) for all samples, while ALAD genotyping was performed using PCR-RFLP for 273 neonate cord blood and 246 children’s blood. The median BBLs of neonates in exposed group vs. the reference group were 10.50 (2.36–40.78) vs. 7.79 (0.8–19.51) for 2004/2005 and 9.41 (9.28–47.60) vs. 5.49 (0.35–18.68) for 2006, while child mean BLLs were 15.31?±?5.79 vs. 9.94?±?4.05 for 2004/2005 and 13.17?±?5.98 vs. 10.04?±?4.85 for 2006. The genotype frequencies in newborns were 98.90 % for the ALAD-1/ALAD-1 homozygote and 1.10 % for the ALAD-1/ALAD-2 heterozygotes, while the values were 95.93 and 4.07 %, respectively, in children. The allele frequencies of the ALAD-1 and ALAD-2 were 99.45 and 0.55 % for newborns, but 97.97 and 2.03 % for children, respectively. No significant differences in blood lead levels were found between ALAD-1/ALAD-1 and ALAD-1/ALAD-2 either in newborns or in children. The frequency distribution of the ALAD-2 allele in newborns from the exposed group was lower than that of the reference group. There were no significant differences, between the two different ALAD genotypes in the lead load of newborns and children. The frequency distribution of ALAD gene does not influence the blood lead levels of newborns and children in this case, which means that the higher lead burden in the exposed children was possibly influenced by e-waste recycling, but not ALAD genotypes.     

Mute swans, Cygnus olor, killed from collision with electrical wires, a study of two situations in Sweden

Different studies indicate that 19-38% of the Swedish ringed Mute Swans (Cygnus olor) are killed by collision with electrical wires. The relative frequency of killed swans is not related to the density or type of electrical wires in the landscape, but to where in the landscape the wires are constructed, and to the time when mass movements of swans occur. Experience (age), bodyweight ("too heavy to raise"), breast muscle weakening ("engine problems") and heavy metal (lead) loads strongly affect the chances of birds avoiding collision; but, swans not belonging to these risk-groups are also killed. Different skeletal injuries were found in dead birds after collision but many of them were not lethal. It was proved, however, that most collision-birds ultimately died from liver damage, probably caused by their heavy bodies hitting the ground.     

Assessment of soil lead exposure in children in Shenyang, China

Soil lead pollution is serious in Shenyang, China. The paper brings together the soil work, the bioaccessibility, and the blood lead data to assess the soil lead exposure in children in Shenyang, China. Approximately 15.25% of the samples were above China Environment Protection Agency guideline concentration for soil Pb to protect human from health risk (350 mgkg(-1)). Pb concentrations varied among use scenarios. The main lead contamination sources are industry emission and automobile exhaust. Bioaccessibility also varied among use scenarios. Children, who ingested soil from industrial area, public parks, kindergarten playground, and commercial area, are more susceptible to soil lead toxicity. The industrial area soil samples presented higher bioaccessibility compared to the other use scenario soil samples contaminated by automobile exhaust. The result also suggested a most significant linear relationship between the level of Pb contamination and the amount of Pb mobilized from soil into ingestion juice. Soil pH seemed to have insignificant influence on bioaccessibility in the present study. Bioaccessibility was mainly controlled by other factors that are not investigated in this study. A linear relationship between children blood lead and soil intestinal bioaccessibility was present in the study. Children who are 4-5 years old are more likely to demonstrate the significant relationship between soil lead bioaccessibility and blood lead as their behaviors place them at greatest risk of soil lead toxicity, and their blood lead levels are more likely to represent recent exposure.     

Mute swans, Cygnus olor, killed from collision with electrical wires, a study of two situations in Sweden

Different studies indicate that 19–38% of the Swedish ringed Mute Swans (Cygnus olor) are killed by collision with electrical wires. The relative frequency of killed swans is not related to the density or type of electrical wires in the landscape, but to where in the landscape the wires are constructed, and to the time when mass movements of swans occur. Experience (age), bodyweight (“too heavy to raise”), breast muscle weakening (“engine problems”) and heavy metal (lead) loads strongly affect the chances of birds avoiding collision; but, swans not belonging to these risk-groups are also killed. Different skeletal injuries were found in dead birds after collision but many of them were not lethal. It was proved, however, that most collision-birds ultimately died from liver damage, probably caused by their heavy bodies hitting the ground.     

Incense burning at home and the blood lead level of preschoolers in Taiwan

The growth and intellectual development of children less than 6 years old may be affected by exposure to low levels of lead. To further reduce environmental lead exposure, this study examined possible household-related factors that affect the blood lead levels of Taiwanese children. In total, based on a stratified random sampling strategy, 934 kindergarten students were recruited throughout Taiwan from April to October 2011 after their parents signed a statement of consent. A venous blood sample was drawn from each participant and analyzed for lead content using inductively coupled plasma mass spectrometry. Information on the demographics and household environment of the study subjects was collected by administering a questionnaire (Table 1). The geometric mean lead level in the blood samples of the study subjects was 1.84 μg/dL with a geometric standard deviation of 1.55. The blood lead level was negatively correlated with household income and parental educational levels (p?p?p?p?=?0.0022). Because the health effects of low levels of lead exposure have been reported in recent years and because no consensus has been reached regarding a safety threshold for blood lead level in children, any trivial factor is worth investigating to further prevent lead exposure in children. Incense burning at home is a common traditional religious activity in Taiwan; therefore, more study is warranted to further eliminate the lead content in incense and reduce lead exposure for the families who practice this activity.     

Investigation into the effects of ingestion of zinc shot by Mallard Ducks (Anas platyrhynchos)

Lead fishing weights and gun shot have been identified as a widespread cause of poisoning of swans and other wildfowl (order Anseriformes). As part of the efforts to find environmentally acceptable substitutes for lead, this paper describes the results obtained from a trial which involved the feeding of zinc shot to groups of mallard (Anas platyrhynchos). Observations of the mallard during the experimental period, post mortem examination, histo-pathological examination and also chemical analysis of liver, kidney and feathers, revealed no ill effects to the dosed birds and indicated that zinc metal in shot from probably presents no detectable health threat to wild birds if ingested.     

Lead contamination of seabirds harvested with lead shot--implications to human diet in Greenland

Lead contamination of seabirds from the use of lead shot in Greenland was studied in thick-billed murre hunted at Nuuk in November 1998. In each bird shot pellets were located and counted using X-ray. The birds were skinned and viscera, head, wings and legs removed, after which the carcass was cooked. The soup and breast meat were then analyzed for lead after removal of visible shot pellets. In the soup the lead concentration was quite low, mean 6.3 micrograms/l (95% confidence interval between 4.4 and 8.2 micrograms/l), whereas breast meat lead values have a mean of 0.22 microgram/g (wet weight basis; 95% confidence interval between 0.10 and 0.36 microgram/g). This is more than 10 times higher than in birds not killed with lead shot. We found no correlation between lead concentration measured and number of pellets recorded in the whole bird or in the soup or in meat. The study indicates that lead in the meat exists as small lead fragments, left during the passage of pellets through the breast. Because of inhomogeneous lead distribution in samples, the uncertainty of estimated lead concentration in breast meat is high. Based on this study, it is concluded that birds killed with lead shot are a significant source of lead, probably the most important single source, of the diet of many people in Greenland. We estimate an intake of 50 micrograms lead from eating one boiled murre with soup. In addition people will occasionally eat whole lead shot pellets which have documented health effects. An intake of 50 micrograms lead is about twice as much as the daily average lead intake from all dietary sources in Denmark, about 25 times the daily lead intake from other marine food items in Greenland, and about one-fourth of the accepted tolerable daily intake.     

Human health risk assessment of lead from mining activities at semi-arid locations in the context of total lead exposure

Lead from historical mining and mineral processing activities may pose potential human health risks if materials with high concentrations of bioavailable lead minerals are released to the environment. Since the Joint Expert Committee on Food Additives of Food and Agriculture Organization/World Health Organization withdrew the Provisional Tolerable Weekly Intake of lead in 2011, an alternative method was required for lead exposure assessment. This study evaluated the potential lead hazard to young children (0–7 years) from a historical mining location at a semi-arid area using the U.S. EPA Integrated Exposure Uptake Biokinetic (IEUBK) Model, with selected site-specific input data. This study assessed lead exposure via the inhalation pathway for children living in a location affected by lead mining activities and with specific reference to semi-arid conditions and made comparison with the ingestion pathway by using the physiologically based extraction test for gastro-intestinal simulation. Sensitivity analysis for major IEUBK input parameters was conducted. Three groups of input parameters were classified according to the results of predicted blood concentrations. The modelled lead absorption attributed to the inhalation route was lower than 2 % (mean?±?SE, 0.9 %?±?0.1 %) of all lead intake routes and was demonstrated as a less significant exposure pathway to children’s blood, compared with ingestion. Whilst dermal exposure was negligible, diet and ingestion of soil and dust were the dominant parameters in terms of children’s blood lead prediction. The exposure assessment identified the changing role of dietary intake when house lead loadings varied. Recommendations were also made to conduct comprehensive site-specific human health risk assessment in future studies of lead exposure under a semi-arid climate.     

Year-to-year correlations in blood metal levels among individuals of two species of North American sea ducks

Sea duck populations have declined in North America. Contaminants, especially metals, have been listed as possible contributing factors. Sea ducks are long-lived. Thus, individuals chronically exposed to elevated metal levels may be at greatest risk. Information about long-term exposure (> or =1year) of individuals to metals is absent. To address this information gap, we examined year-to-year correlations among individual White-Winged Scoters and King Eiders in levels of blood cadmium, lead, mercury and selenium. Positive correlations (r> or =0.43), were found in six, five, five and two of seven correlations for cadmium, selenium, lead and mercury. Thus, certain individuals of these species may be exposed over two or more years to higher levels of cadmium, selenium and lead (but apparently not mercury) than other individuals. Single blood samples are appropriate metrics of exposure for studies that examine long-term effects of certain metals on these birds.