Prevalence and Risk Factors of Elevated Blood Lead in Children in Gold Ore Processing Communities, Zamfara, Nigeria, 2012.

BACKGROUND: In March 2010, Medecins Sans Frontieres/Doctors Without Borders detected an outbreak of acute lead poisoning in Zamfara State, northwestern Nigeria, linked to low-technology gold ore processing. The outbreak killed more than 400 children ≤5 years of age in the first half of 2010 and has left more than 2,000 children with permanent disabilities. OBJECTIVES: The aims of this study were to estimate the statewide prevalence of children ≤5 years old with elevated blood lead levels (BLLs) in gold ore processing and non-ore-processing communities, and to identify factors associated with elevated blood lead levels in children. METHODS: A representative, population-based study of ore processing and non-ore-processing villages was conducted throughout Zamfara in 2012. Blood samples from children, outdoor soil samples, indoor dust samples, and survey data on ore processing activities and other lead sources were collected from 383 children ≤5 years old in 383 family compounds across 56 villages. RESULTS: 17.2% of compounds reported that at least one member had processed ore in the preceding 12 months (95% confidence intervals (CI): 9.7, 24.7). The prevalence of BLLs ≥10 µg/dL in children ≤5 years old was 38.2% (95% CI: 26.5, 51.4) in compounds with members who processed ore and 22.3% (95% CI: 17.8, 27.7) in compounds where no one processed ore. Ore processing activities were associated with higher lead concentrations in soil, dust, and blood samples. Other factors associated with elevated BLL were a child's age and sex, breastfeeding, drinking water from a piped tap, and exposure to eye cosmetics. CONCLUSIONS: Childhood lead poisoning is widespread in Zamfara State in both ore processing and non-ore-processing settings, although it is more prevalent in ore processing areas. Although most children's BLLs were below the recommended level for chelation therapy, environmental remediation and use of safer ore processing practices are needed to prevent further exposures. PATIENT CONSENT: Obtained. ETHICS APPROVAL: The study protocol was approved by the US Centers for Disease Control Institutional Review Board-A and the National Health Research Ethics Committee of Nigeria. COMPETING INTERESTS: The authors declare no competing financial interests.

High concentration of blood lead levels among young children in Bagega community, Zamfara - Nigeria and the potential risk factor.

INTRODUCTION: In May 2010, lead poisoning (LP) was confirmed among children <5years (U5) in two communities in Zamfara state, northwest Nigeria. Following reports of increased childhood deaths in Bagega, another community in Zamfara, we conducted a survey to investigate the outbreak and recommend appropriate control measures. METHODS: We conducted a cross-sectional survey in Bagega community from 23rd August to 6th September, 2010. We administered structured questionnaires to parents of U5 to collect information on household participation in ore processing activities. We collected and analysed venous blood samples from 185 U5 with LeadCare II machine. Soil samples were analysed with X-ray fluorescence spectrometer for lead contamination. We defined blood lead levels (BLL) of >10ug/dL as elevated BLL, and BLL ≥45ug/dL as the criterion for chelation therapy. We defined soil lead levels (SLL) of ≥400 parts per million (ppm) as elevated SLL. RESULTS: The median age of U5 was 36 months (Inter-quartile range: 17-48 months). The median BLL was 71µg/dL (range: 8-332µg/dL). Of the 185 U5, 184 (99.5%) had elevated BLL, 169 (91.4%) met criterion for CT. The median SLL in tested households (n = 37) of U5 was 1,237ppm (range: 53-45,270ppm). Households breaking ore rocks within the compound were associated with convulsion related-children's death (OR: 5.80, 95% CI: 1.08 - 27.85). CONCLUSION: There was an LP outbreak in U5 in Bagega community possibly due to heavy contamination of the environment as a result of increased ore processing activities. Community-driven remediation activities are ongoing. We recommended support for sustained environmental remediation, health education, intensified surveillance, and case management.

Assessment of blood lead levels among children aged ≤ 5 years--Zamfara State, Nigeria, June-July 2012.

Since 2010, Nigerian state and federal governments and the international community have been responding to an outbreak of lead poisoning caused by the processing of lead-containing gold ore in Zamfara State, Nigeria, that resulted in the deaths of approximately 400 children aged ≤ 5 years. Widespread education, surveys of high-risk villages, testing of blood lead levels (BLLs), medical treatment, and environmental cleanup all have been implemented. To evaluate the success of these remediation efforts in reducing the prevalence of lead poisoning and dangerous work practices, a population-based assessment of children's BLLs and ore processing techniques was conducted during June-July 2012. The assessment found few children in need of medical treatment, significantly lower BLLs, and substantially less exposure of children to dangerous work practices. Public health strategies designed to identify and treat children with lead poisoning, clean up existing environmental hazards, and prevent children from being exposed to dangerous ore processing techniques can produce a sustained reduction in BLLs.

Analysis of a novel field dilution method for testing samples that exceed the analytic range of point-of-care blood lead analyzers.

Investigators developed and evaluated a dilution method for the LeadCare II analyzer (LCII) for blood lead levels >65 µg/dL, the analyzer's maximum reporting value. Venous blood samples from lead-poisoned children were initially analyzed in the field using the dilution method. Split samples were analyzed at the US Centers for Disease Control and Prevention (CDC) laboratory using both the dilution method and inductively coupled plasma-mass spectrometry (ICP-MS). The concordance correlation coefficient of CDC LCII vs. ICP-MS values (N = 211) was 0.976 (95 % confidence interval (CI) 0.970-0.981); of Field LCII vs. ICP-MS (N = 68) was 0.910 (95% CI 0.861-0.942), and CDC LCII vs. Field LCII (N = 53) was 0.721 (95% CI 0.565-0.827). Sixty percent of CDC and 54% of Field LCII values were within ±10% of the ICP-MS value. Results from the dilution method approximated ICP-MS values and were useful for field-based decision-making. Specific recommendations for additional evaluation are provided.

Childhood lead poisoning associated with gold ore processing: a village-level investigation-Zamfara State, Nigeria, October-November 2010.

BACKGROUND: During May-June 2010, a childhood lead poisoning outbreak related to gold ore processing was confirmed in two villages in Zamfara State, Nigeria. During June-September of that year, villages with suspected or confirmed childhood lead poisoning continued to be identified in Zamfara State. OBJECTIVES: We investigated the extent of childhood lead poisoning [≥ 1 child with a blood lead level (BLL) ≥ 10 µg/dL] and lead contamination (≥ 1 soil/dust sample with a lead level > 400 parts per million) among villages in Zamfara State and identified villages that should be prioritized for urgent interventions. METHODS: We used chain-referral sampling to identify villages of interest, defined as villages suspected of participation in gold ore processing during the previous 12 months. We interviewed villagers, determined BLLs among children < 5 years of age, and analyzed soil/dust from public areas and homes for lead. RESULTS: We identified 131 villages of interest and visited 74 (56%) villages in three local government areas. Fifty-four (77%) of 70 villages that completed the survey reported gold ore processing. Ore-processing villages were more likely to have ≥ 1 child < 5 years of age with lead poisoning (68% vs. 50%, p = 0.17) or death following convulsions (74% vs. 44%, p = 0.02). Soil/dust contamination and BLL ≥ 45 µg/dL were identified in ore-processing villages only [50% (p < 0.001) and 15% (p = 0.22), respectively]. The odds of childhood lead poisoning or lead contamination was 3.5 times as high in ore-processing villages than the other villages (95% confidence interval: 1.1, 11.3). CONCLUSION: Childhood lead poisoning and lead contamination were widespread in surveyed areas, particularly among villages that had processed ore recently. Urgent interventions are required to reduce lead exposure, morbidity, and mortality in affected communities.

Genotoxicity of goniothalamin in CHO cell line.

Goniothalamin (GTN) is a styrylpyrrone derivative from Goniothalamus umbrosus and other Annonaceae species. It has been shown to have anti-cancer and apoptosis-inducing properties against various human tumour and animal cell lines. The compound has also been shown to be active in vivo against DMBA-induced rat mammary tumours and was reported as an anti-fertility agent in rats. The aim of our study was to assess the genotoxicity of GTN in CHO cells using the UKEMS guidelines. A metabolic activation fraction (S9) was prepared according to standard methods. The methylthiazoletetrazolium (MTT) screening assay was then carried out to determine the cytotoxicity index (IC50) of GTN. The average IC50 value was 12.45 (+/- 3.63)microM. The mitotic index (MI) assay was then performed to determine the clastogenicity indices (MI(C25), MI(C50) and MI(C100)) of GTN. The chromosome aberration (CA) induction assay using air-dried metaphase spread was then performed to investigate the clastogenic effects of goniothalamin. Benzo[a]pyrene (BaP) and ethylmethanesulphonate (EMS) were used as positive controls in the presence and absence of S9 metabolic activation, respectively. The anti-genotoxicity effect of GTN was also assessed using a combination of GTN and EMS, and GTN and BaP. Dose-responses of CA frequencies were determined for both, the genotoxicity and anti-genotoxicity effects. GTN on its own and when combined with positive controls, was found to induce and enhance CA, respectively. Chromatid and whole chromosome breaks/gaps, as well as interchanges, endoreduplications and ring chromosomes were the main types of aberration induced by GTN. The overall clastogenic effect of GTN was statistically significant. In conclusion, GTN is potentially a genotoxic or clastogenic substance without any anti-genotoxic properties.