High blood levels of lead in children aged 6-36 months in Kathmandu Valley, Nepal: A cross-sectional study of associated factors

Association of blood lead level with neurobehavior and neurotransmitter expressions in Indian children

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BLL had a significant direct correlation with abnormal neurobehavior.

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Serum serotonin levels were significantly lower in children with high blood lead levels (BLL).

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Serum serotonin and dopamine receptor expression were upregulated in children with high BLL.

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Serum serotonin levels had significant negative association with adverse neurobehavior.

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Dopamine receptor expression had significant positive association with adverse neurobehavior.

Present study aimed to assess the alterations in neurotransmitter expression and its association with Blood Lead Level (BLL) and neurobehavioral pattern in children. 72 school going children were recruited. Blood lead levels were determined by Atomic Absorption Spectrophotometer. Neurobehavioral state was assessed by means of population specific scale i.e. CPMS (Childhood Psychopathological measurement Schedule). Serum serotonin and dopamine were estimated by ELISA, receptor and transporter gene expressions were assessed by quantitative real time PCR. Significant positive correlation was observed between Total CPMS score (i.e. adverse neurobehaviour) and BLL. Further, serum serotonin levels and dopamine receptor expression showed a negative and positive association with BLL, respectively. In similarity, serum serotonin levels showed a negative correlation and dopamine receptor expression had a significant positive correlation with total CPMS score. Environmental exposure to Lead (Pb) may result in significant alterations in the neurotransmitter levels which may be associated with neurobehavioral changes in the children exposed to Pb.

Body iron and lead status in early childhood and its effects on development and cognition: a longitudinal study from urban Vellore

OBJECTIVE

Early childhood factors can have persisting effects on development and cognition in children. We propose to explore the trends of Fe deficiency and Pb toxicity in early childhood and their association with child development at 2 years of age and cognition at 5 years.

DESIGN

Longitudinal birth cohort study.

SETTING

Urban slum, Vellore, India.

PARTICIPANTS

Children enrolled at birth were followed up regularly in the first 2 years with developmental and cognitive assessments at 2 and 5 years of age, respectively.

RESULTS

The birth cohort enrolled 251 children with 228 children followed up at 2 years and 212 at 5 years of age. Fe deficiency (ID) was highest at 15 months of age and improved subsequently at 24 months. Blood Pb levels (BLL) remained high at all age groups with an increasing trend with age; 97 % at 36 months having high BLL. Persistent high mean BLL at 15 and 24 months had negative association with both cognition and expressive language raw scores of 24 months, while high mean BLL at 15, 24 and 36 months had no significant association with any of the domains of cognition at 5 years of age. Early childhood cumulative body Fe status at 7, 15 and 24 months did not show any association with child development at 2 years, but was associated with verbal, performance and processing speed components of cognition at 5 years.

CONCLUSIONS

Optimising body Fe status and limiting Pb exposure in early childhood can augment child development and school entry cognition.

Blood Lead Levels in Children Living Near an Informal Lead Battery Recycling Workshop in Patna, Bihar

BACKGROUND

Lead can cause significant biological and neurologic damage, even at small concentrations, and young children are at higher risk. Informal recycling of lead batteries and lead-based workshops/industries have increased the burden of lead toxicity in developing countries, including India. Many informal recycling lead battery workshops have been established by the local people of Patna, Bihar as self-employment opportunities. However, most of the residents are not aware of the risk factors associated with lead poisoning.

OBJECTIVES

The present pilot study aimed to assess blood lead levels (BLLs) and hemoglobin levels among children aged between 3 to 12 years in the settlement of Karmalichak near Patna, India.

MATERIALS AND METHODS

Children residing near the informal lead battery manufacturing unit were selected for BLL assessment. A total of 41 children were enrolled in the questionnairebased survey.

RESULTS

All the children in the present study had detectable lead concentrations in their blood. Only 9% of the studied children had a BLL ≤5 μg/dl, while 91% children had a BLL above >5 μg/dl.

CONCLUSIONS

The present study carried out in children of Karmalichak region of Patna, India was an attempt to better understand the problem of lead toxicity, describe the epidemiology of its adverse effects, identify sources and routes of exposure, illustrate the clinical effects and develop strategies of prevention so that remedial measures may be taken by government agencies and regulatory bodies. In view of the high lead levels in children in the study area, attempts are being made to develop strategies for future prevention by relocating the informal battery recycling workshops from the area. Moreover, parents have been advised to increase nutritional supplementation of children by providing calcium-, iron- and zinc-rich foods, including milk and vegetables.

PARTICIPANT CONSENT

Obtained.

ETHICAL APPROVAL

The study was approved by the ethical committee of Era's Lucknow Medical College & Hospital, Era University, Lucknow (India).

COMPETING INTERESTS

The authors declare no competing financial interests.

Neuropathological lesions in the brains of goats in North-Western Nigeria: possible impact of artisanal mining

Indiscriminate small-scale artisanal gold mining activities were reported to have caused anthropogenic heavy metal environmental pollution in Zamfara State, north-western Nigeria. There is little or no information on the neurotoxic effects and related neuropathological lesions due to environmental pollution in the animal population. Therefore, this work investigated the concentration of heavy metal and associated lesions in the brain of goats around an artisanal mining site in Zamfara. Brain samples were collected from 40 goats at slaughter slabs in Bagega (Zamfara State) while 15 goats with the same demography but without a history of environmental exposure at the time of this study served as controls. The concentration of lead and cadmium in brain tissue and histopathologic changes were assessed using atomic absorption spectrophotometry, histology and immunohistochemistry. The metal concentrations were significantly higher in exposed goats than in the unexposed animals. Cresyl violet staining and glial fibrillary acidic protein (GFAP) immunohistochemistry indicated chromatolysis and increased astrocytic activity respectively in the exposed goats. This study is of epidemiological importance as it shows a generalised increase of the metal concentrations in the brain of goats exposed to artisanal mining in Zamfara, north-western Nigeria. This could have health effects on the animals associated with nervous co-ordination, growth and development and as a good sentinel for pathogenesis of the heavy metal exposure.

Elevated Blood Lead Levels Among Resettled Refugee Children in Ohio, 2009-2016

Objectives. To assess the prevalence of and the demographic factors for elevated blood lead level (EBLL; ≥ 5 µg/dL) at resettlement among newly admitted refugee children. Methods. This cross-sectional study used data from the postresettlement refugee medical screening of 5661 children resettled in Ohio from 2009 to 2016. We computed prevalence of EBLL and adjusted prevalence ratio with modified Poisson regression modeling. Results. Overall, 22.3% of children younger than 18 years and 27.1% of those younger than 6 years had an EBLL. Children resettled from a South Asia region including Afghanistan (EBLL prevalence = 56.2%; 95% confidence interval [95% CI] = 48.1%, 64.3%), Nepal (44.0%; 95% CI = 33.7%, 54.1%), Bhutan (32.8%; 95% CI = 30.4%, 35.9%), and Burma (31.8%; 95% CI = 27.5%, 35.9%) had the highest prevalence of EBLLs. In addition, those younger than 6 years (prevalence ratio [PR] = 2.0; 95% CI = 1.6, 2.6), male (PR = 1.3; 95% CI = 1.1, 1.4), and screened within 30 days of arrival (PR = 1.7; 95% CI = 1.1, 2.5) had significantly higher EBLL prevalence than did children aged 13 years and older, female, and screened 90 days after arrival. Conclusions. The overall high proportion of EBLL and variation in EBLL by country of origin among resettled refugee children in the United States warrant comprehensive, yet tailored, guidelines for health professionals and resettlement and government agencies for better prevention and awareness programs targeting these high-risk children.

Lead exposure is associated with risk of impaired coagulation in preschool children from an e-waste recycling area

Environmental lead exposure leads to various deleterious effects on multiple organs and systems, including the hematopoietic system. To explore the effects of lead exposure on platelet indices in preschool children from an informal, lead-contaminated electronic waste (e-waste) recycling area, we collected venous blood samples from 466 preschool children (331 from an e-waste area (Guiyu) and 135 from a non-e-waste area (Haojiang)). Child blood lead levels (BLLs) were determined by graphite furnace atomic absorption spectrophotometry, while platelet indices were quantified using a Sysmex XT-1800i hematology analyzer. Higher blood lead levels are observed in e-waste lead-exposed preschool children. Significant relationships between high blood lead levels (exceeding current health limits) and elevated platelet count (PLT), plateletcrit (PCT), mean platelet volume (MPV), and platelet large cell ratio (P-LCR) were also uncovered. Furthermore, the median PLT and PCT levels of children from the exposed group both exceeded the respective recommended maximum reference range value, whereas the reference group did not. Location of child residence in Guiyu and BLLs were both risk factors related to platelet indices. These results suggest that high blood lead exposure from e-waste recycling may increase the risk of an amplified coagulation process through the activation of platelets in preschool children.

Correction: High blood levels of lead in children aged 6-36 months in Kathmandu Valley, Nepal: A cross-sectional study of associated factors

[This corrects the article DOI: 10.1371/journal.pone.0179233.].