Association between blood lead exposure and mental health in pregnant women: Results from the Japan environment and children's study.

OBJECTIVE: Although environmental lead exposure has decreased, several studies have shown that low-level lead exposure can result in adverse psychological symptoms. However, few studies have examined lead neurotoxicity in pregnant women. We investigated the association between lead exposure and psychological symptoms in pregnant women, and between socio-economic status and blood lead levels. METHODS: Blood lead levels were measured in 17,267 pregnant women in the Japan Environment and Children's Study. Odds ratios (ORs) for high blood lead levels were calculated using multinomial logistic regression. Psychological symptoms were assessed using the Kessler Psychological Distress Scale (K6). ORs for depression (K6 ≥ 13 or ≥5) were calculated using logistic regression with adjustment for potential confounders. RESULTS: The geometric mean of whole blood lead levels was 0.58 µg/dl (range 0.14-6.75 µg/dl). Higher blood lead levels were associated with older age (OR 1.79, 9 5% confidence interval [CI] 1.46-2.19), unmarried status (OR 1.75, 95 % CI 1.31-2.33), lower household income (OR 1.76, 95 % CI 1.38-2.24), and lower educational attainment (OR 1.34, 95 % CI 1.20-1.48). The percentage of women with K6 scores ≥13 and ≥5 was 3 % and 28.2 %, respectively. There was no significant association between lead exposure and K6 score (K6 ≥ 13: OR 1.00, 95 % CI 0.76-1.32; K6 ≥ 5: OR 0.98, 95 % CI 0.88-1.09). CONCLUSION: Our results indicate a small but significant association between higher blood lead levels and lower socio-economic status in a population with low blood lead levels, but no association between low-level lead exposure and psychological symptoms.

Environmental and Occupational Lead Exposure Among Children in Cairo, Egypt: A Community-Based Cross-Sectional Study.

The aim of this study was to assess childhood lead exposure in a representative sample of Cairo, and to investigate the possible risk factors and sources of exposure. This cross-sectional study was conducted from November 2014 through April 2015. The target population was children aged 6 to 18 years, recruited into 4 groups, garbage city, moderate-living standard area, urban and suburban schools, and workshops in the city of Cairo. Blood lead levels (BLLs) and hemoglobin (Hb) concentrations were measured. Also, potential local environmental sources were assessed for hazardous lead contamination. Analysis on 400 participants has been carried out. A total of 113 children had BLLs in the range 10 to 20 µg/dL. Smoking fathers, housing conditions, playing outdoors, and exposure to lead in residential areas were significantly correlated with high BLLs. The mean values of hemoglobin were inversely correlated with BLLs. Children involved in pottery workshops had the highest BLLs and the lowest Hb values with a mean of (43.3 µg/dL and 8.6 g/dL, respectively). The mean value of environmental lead in workshop areas exceeded the recommended levels. Also, those values measured in dust and paint samples of garbage city were significantly high. Moreover, the mean lead levels in the soil samples were significantly higher in urban schools (P = 0.03) than the suburban ones. Childhood lead poisoning accounts for a substantial burden in Egypt, which could be preventable. Development of national prevention programs including universal screening program should be designed to reduce incidence of lead toxicity among children.

[Outbreak of lead poisoning associated with Ayurvedic medicine]. / Brote de saturnismo asociado a un tratamiento basado en la medicina ayurvédica.

BACKGROUND AND OBJECTIVE: Lead poisoning is normally caused by repeated occupational inhalation of lead. However, lead may also be absorbed through the digestive route. Some alternative medical treatments, such as Ayurvedic medicine, can also contain lead and may result in poisoning. PATIENTS AND METHOD: We collected cases of lead poisoning related to Ayurvedic treatments attended at the Hospital Clinic of Barcelona. RESULTS: Two female patients, aged 45 and 57 years, respectively, who initiated Ayurvedic treatments which involved the ingestion of various medicaments, were included. The first patient presented with anemia and abdominal pain. The lead level was 74µg/dL and free erythrocyte protoporphyrin was 163µg/dL. She was treated with intravenous calcium disodium ethylenediaminetetraacetic acid (CaNa2EDTA) and later with oral dimercaptosuccinic acid (DMSA) with a good evolution. The second patient presented with abdominal pain and a Burton's line. The lead level was 52µg/dL and free erythrocyte protoporphyrin was 262µg/dL. She was treated with oral DMSA and evolved favorably. Lead concentrations in some of the tablets supplied to the patients reached 2,003 and 19,650µg/g of tablet. CONCLUSIONS: Lead poisoning may result from treatments based on Ayurvedic medicine and may reach epidemic proportions. Health control of alternative medicines is necessary.

Association of maternal and child blood lead and hemoglobin levels with maternal perceptions of parenting their young children.

Biological and psychosocial factors affect child development and behavior. Whereas biological underpinnings behind the neurotoxic effects of lead are studied extensively, the effects of psychosocial factors contributing to poor behavioral outcomes in lead-exposed children are not well understood. Parental attributes and practices may moderate or mediate the effects of lead on children's behavioral outcomes. We investigated the hypothesis that maternal and child lead and hemoglobin levels are associated with maternal perceptions of their parenting. Specifically, we hypothesized that children with higher blood lead (BLL) and lower hemoglobin concentrations would be associated with poorer maternal self-assessments of their parenting skills or the mother-child relationship. Children aged 13-55 months and their mothers (n=109) were recruited from among the participants of a previous lead and anemia screening study and from preschools in Montevideo, Uruguay. The mother-child pair attended two study visits: one to collect biological samples and answer demographic and child questionnaires, including statements regarding parenting; and a second to evaluate maternal IQ, depression and stress, and child development. Of the children, 51.6% had blood lead concentrations (BLLs) ≥ 5 µg/dL, 18.0% had anemia, and 8% had both conditions. Among mothers, 48.4% had BLLs ≥ 5 µg/dL, 16.0% had anemia, and 11% had both. BLLs ≥ 5 µg/dL in mother or child were associated with lower maternal perceptions of being skilled at discipline (p<0.05). Maternal anemia was associated with lower likelihood that mothers would let their children explore and play (p<0.05), whereas child anemia was associated with maternal perception of lower emotional support (p<0.01). In addition to shared environmental exposures, parenting and family interactions need to be considered as potentially contributing factors to poorer outcomes in lead-exposed children.

Severe neurotoxicity following ingestion of tetraethyl lead.

Organic lead compounds are potent neurotoxins which can result in death even from small exposures. Traditionally, these compounds are found in fuel stabilizers, anti-knock agents, and leaded gasoline. Cases of acute organic lead intoxication have not been reported for several decades. We report a case of a 13-year-old Iraqi male who unintentionally ingested a fuel stabilizer containing 80-90% tetraethyl lead, managed at our combat support hospital. The patient developed severe neurologic symptoms including agitation, hallucinations, weakness, and tremor. These symptoms were refractory to escalating doses of benzodiazepines and ultimately required endotracheal intubation and a propofol infusion. Adjunctive therapies included chelation, baclofen, and nutrition provided through a gastrostomy tube. The patient slowly recovered and was discharged in a wheelchair 20 days after ingestion, still requiring tube feeding. Follow-up at 62 days post-ingestion revealed near-resolution of symptoms with residual slurred speech and slight limp. This case highlights the profound neurotoxic manifestations of acute organic lead compounds.

Blood lead, serum homocysteine, and neurobehavioral test performance in the third National Health and Nutrition Examination Survey.

Regression analysis was used to estimate and test for relationships between blood lead, serum folate, red blood cell folate, serum vitamin B12, serum homocysteine, and neurobehavioral test performance in adults, 20-59 years old, participating in the third National Health and Nutrition Examination Survey. The three neurobehavioral tests included in the survey were simple reaction time, symbol-digit substitution, and serial digit learning. Serum folate, red blood cell folate, and serum vitamin B12 decreased as the blood lead concentration increased. Serum homocysteine increased as the blood lead concentration increased. Serum homocysteine decreased as the serum folate and serum vitamin B12 concentrations increased. Neurobehavioral test performance was not related to the blood lead, serum folate, or serum vitamin B12 concentrations. In adults 20-39 years old, performance on the serial digit learning test improved as the serum homocysteine concentration increased. In adults 40-59 years old, neurobehavioral test performance was not related to the serum homocysteine concentration. Homocysteine may impair cognitive function by acting at N-methyl-D-aspartate receptors, and improve cognitive function by acting at N-methyl-D-aspartate or gamma-aminobutyric acid receptors.

Are brain volumes based on magnetic resonance imaging mediators of the associations of cumulative lead dose with cognitive function?

The authors used cross-sectional data (2001-2003) to consider the pathway through which past occupational lead exposure impacts cognitive function. They were motivated by studies linking cumulative lead dose with brain volumes, volumes with cognitive function, and lead dose with cognitive function. It was hypothesized that the brain regions associated with lead mediate a portion of the relation between lead dose and cognitive function. Data were derived from an ongoing US study of 513 former organolead manufacturing workers. Magnetic resonance imaging was used to perform a novel analysis to investigate mediation. Volumes associated with cognitive function and lead dose were derived by using registered images and were used in a subsequent mediation analysis. Cumulative lead dose was associated with adverse function in the visuo-construction, executive function, and eye-hand coordination domains. Regarding these domains, there was strong evidence of volumetric mediation of lead's effect on cognition in the visuo-construction domain and a moderate amount for executive function and eye-hand coordination. A second path-analysis-based approach was also used. To address the possibility that chance associations explained these findings, a permuted analysis was conducted, the results of which supported the mediation inferences. The approach to evaluating volumetric mediation may have general applicability in epidemiologic neuroimaging settings.

Intoxicação por chumbo no ambiente de trabalho / Lead poisoning in the workplace

O presente estudo tem por objetivo abordar a intoxicação por chumbo no ambiente ocupacional. Inicialmente, buscou-se contemplar a etiopatogenia do saturnismo, onde se pode afirmar que os efeitos tóxicos do chumbo dependem não só da quantidade absorvida como da tolerãncia individual e de sua distribuição no organismo: foi visto o processo de absorção, distribuição e eliminação do chumbo, sua epidemiologia, quadro clínico, diagnóstico, tratamento e prevenção. O estudo conclui qua as medidas de primeira linha na prevenção das exposições a chumbo estão no plano da prevenção primária, ou seja, trata-se de medidas que buscam eliminar ou reduzir a exposição excessiva. A quelação com EDTA (Ácido Etileno Diamino tetra-acético) é o que melhores resultados apresentam para o tratamento da intoxicação por chumbo, sendo considerado o de escolha principalmente nas intoxicações graves.

Impact of cognitive reserve on the relationship of lead exposure and neurobehavioral performance.

BACKGROUND: Cognitive reserve (CR)--a construct studied in many neurologic disorders--refers to the maintenance of cognitive performance in spite of ongoing underlying brain pathology. OBJECTIVE: We hypothesized that a dose-effect relationship would exist between chronic occupational lead exposure and cognitive effects in workers with low CR but not in workers with high CR and identical lead exposure, and that level of CR would not influence the relationship between lead exposure and motor performance. METHODS: We stratified currently employed lead smelter workers by Wide Range Achievement Test-R for reading (WRAT), a recognized measure of CR, into loCR and hiCR groups. From these two groups we matched 56 pairs on working lifetime weighted blood lead (TWA). We performed a factor analysis on 14 neuropsychological outcome variables. Within each CR group regression analyses after adjusting for age, alcohol use, and depression scale score tested for dose-effect relationships between TWA and outcome variables. RESULTS: Both CR groups had comparable age, years employed, alcohol use, and current blood lead levels. Factor analysis provided three factors and five tests used in the regression analyses. Significant dose-effect relationships between TWA and cognitive tests present only in the loCR group included Attention Factor and Digit Symbol. Both CR groups demonstrated significant dose-effect relationships on the Motor Factor. CONCLUSION: This study found that cognitive reserve protects against the effect of chronic lead exposure on select measures of cognitive performance but not on motor performance.

Ayurvedic medicine: patients in peril from plumbism.

Heavy metals are commonly incorporated into Ayurvedic preparations as ashes or 'bhasmas'. A widely disseminated belief within Ayurvedic medicine is that these heavy metals can be valuable therapeutic components. Western toxicology refutes this contention. We report eight cases of lead poisoning occurring in or near the Auckland region of New Zealand. In all cases, poisoning was attributable to consumption of Ayurvedic 'herbal medicines'. Whole blood lead levels ranged from 1.5 to 6.9 micromol/L. Six patients had symptomatic lead poisoning, requiring treatment with chelation therapy. A high index of suspicion is required to detect lead poisoning, which should be suspected in people taking Ayurvedic remedies, especially if they have associated anaemia or abdominal symptoms.

Pre- and posttreatment MR imaging findings in lead encephalopathy.

A 41-year-old man suspected of having lead poisoning was evaluated with MR imaging before and after British antilewisite therapy. The MR imaging findings showed bilateral symmetric involvement of the occipital lobe, affecting predominantly the gray-white matter junction and the subcortical white matter. A right cerebellar lesion was noted, with focal hyperintensities involving the gray-white matter. Similar lesions were seen in the temporal, parietal, and frontal regions. These lesions resolved after chelation therapy.

Multivariate modeling of age and retest in longitudinal studies of cognitive abilities.

Longitudinal multivariate mixed models were used to examine the correlates of change between memory and processing speed and the contribution of age and retest to such change correlates. Various age- and occasion-mixed models were fitted to 2 longitudinal data sets of adult individuals (N>1,200). For both data sets, the results indicated that the correlation between the age slopes of memory and processing speed decreased when retest effects were included in the model. If retest effects existed in the data but were not modeled, the correlation between the age slopes was positively biased. The authors suggest that although the changes in memory and processing speed may be correlated over time, age alone does not capture such a covariation.

[Diagnostic problems in case of environmental exposure to tetraethyl lead]. / Problemy diagnostyczne w przypadku srodowiskowego narazenia na czteroetylek olowiu.

UNLABELLED: The aim of this study was the presentation of the chronic tetraethyl lead poisoning of the 4 person family in the place of settlement. CASE REPORT: 15.5-years-old man was admitted to the regional Pediatric Ward because of changes of behavior, hallucinations, agitation. Nausea, vomiting, metallic taste and diarrhea were observed prior to the admission. In the case history, there were no data suggested of the toxic origin of the disorder . The CSF examination and CT of the brain were normal. Increased activity of CPK, ALT, AST, GTP, LDH in the blood were found. Paranoid syndrome was diagnosed by psychiatric evaluation. The patients' mother presented similar signs in almost the same time. The laboratory tests of the blood taken from the patients' father and older brother revealed the increase activity of the same enzymes (CPK, ALT, AST, LDH). All family was admitted to the Department of Clinical Toxicology in Kraków because of suspicion of the heavy metal poisoning. The toxicological laboratory test showed in all described patients the toxic serum lead concentration accordingly: 440 microg/l--older brother, 490 microg/l--father, 508 microg/l--mother and 635 microg/l--primary described patient. Because of the fact, that were no characteristic for lead poisoning changes in blood picture, the toxicological investigations were continued. As a result of these examinations presence of a diethyl lead in urine was confirmed. In the evaluation of the multiorgan damages connected with tetraethyl lead poisoning, we paid special attention on CSN dysfunctions. The USG and scintigraphy examinations revealed the liver damage. The different kinds of arrhythmias indicated on cardiovascular system damage. Based on clinical presentation and laboratory investigations the chronic tetraethyl lead poisoning was diagnosed.