Environmental toxins; their impact on children's health

Engaging, recruiting, and retaining pregnant people from marginalized communities in environmental health cohort studies: a scoping review

OBJECTIVES

To identify barriers to and strategies for improving the representation of pregnant people from marginalized communities in pregnancy cohort studies that measure environmental chemicals.

METHODS

Guided by the Arksey O'Malley and Levac Frameworks, we conducted a scoping review of peer-reviewed literature published between 2000 and 2022. Included studies discussed barriers and/or strategies related to engaging, recruiting, and retaining pregnant participants or participants of reproductive age from marginalized communities into environmental health research.

RESULTS

Twenty-nine peer-reviewed articles were included in the review. Overall, 31% (9/29) of the studies reported on engagement, recruitment, and retention of participants from racialized communities, 10% (3/29) reported on involvement of participants identifying as Indigenous, and 10% (3/29) of studies reported on participants living in households or areas of low socioeconomic status. We identified four key barriers: participant burden, social inequities, lack of trust, and lack of cultural relevance. We reported identified strategies to mitigate these barriers.

CONCLUSION

Although there is limited coverage in the literature on strategies to effectively engage people from marginalized communities in environmental health pregnancy cohort studies, our findings suggest that applying a health equity and social justice lens to research may help address barriers that exist at the individual, interpersonal, community, institutional, and policy levels. Findings from this review may have important implications for planning future pregnancy cohort studies and ensuring that communities who are disproportionately affected by environmental chemical exposures may be better represented in research and considered in policy decisions.

Metal mixture exposures and serum lipid levels in childhood: the Rhea mother-child cohort in Greece

BACKGROUND

Growing evidence suggests that cardiovascular disease develops over the lifetime, often beginning in childhood. Metal exposures have been associated with cardiovascular disease and important risk factors, including dyslipidemia, but prior studies have largely focused on adult populations and single metal exposures.

OBJECTIVE

To investigate the individual and joint impacts of multiple metal exposures on lipid levels during childhood.

METHODS

This cross-sectional study included 291 4-year-old children from the Rhea Cohort Study in Heraklion, Greece. Seven metals (manganese, cobalt, selenium, molybdenum, cadmium, mercury, and lead) were measured in whole blood using inductively coupled plasma mass spectrometry. Serum lipid levels included total cholesterol, triglycerides, high-density lipoprotein (HDL) cholesterol, and low-density lipoprotein (LDL) cholesterol. To determine the joint and individual impacts of child metal exposures (log2-transformed) on lipid levels, Bayesian kernel machine regression (BKMR) was employed as the primary multi-pollutant approach. Potential effect modification by child sex and childhood environmental tobacco smoke exposure was also evaluated.

RESULTS

BKMR identified a positive association between the metal mixture and both total and LDL cholesterol. Of the seven metals examined, selenium (median 90.6 [IQR = 83.6, 96.5] µg/L) was assigned the highest posterior inclusion probability for both total and LDL cholesterol. A difference in LDL cholesterol of 8.22 mg/dL (95% CI = 1.85, 14.59) was observed when blood selenium was set to its 75th versus 25th percentile, holding all other metals at their median values. In stratified analyses, the positive association between selenium and LDL cholesterol was only observed among boys or among children exposed to environmental tobacco smoke during childhood.

IMPACT STATEMENT

Growing evidence indicates that cardiovascular events in adulthood are the consequence of the lifelong atherosclerotic process that begins in childhood. Therefore, public health interventions targeting childhood cardiovascular risk factors may have a particularly profound impact on reducing the burden of cardiovascular disease. Although growing evidence supports that both essential and nonessential metals contribute to cardiovascular disease and risk factors, such as dyslipidemia, prior studies have mainly focused on single metal exposures in adult populations. To address this research gap, the current study investigated the joint impacts of multiple metal exposures on lipid concentrations in early childhood.

Effects of chronic home radon exposure on cognitive, behavioral, and mental health in developing children and adolescents

Introduction

It is well-established that chronic exposure to environmental toxins can have adverse effects on neuropsychological health, particularly in developing youths. However, home radon, a ubiquitous radiotoxin, has been seldom studied in this context. In the present study, we investigated the degree to which chronic everyday home radon exposure was associated with alterations in transdiagnostic mental health outcomes.

Methods

A total of 59 children and adolescents ages 6- to 14-years-old (M = 10.47 years, SD = 2.58; 28 males) completed the study. Parents completed questionnaires detailing aspects of attention and executive function. We used a principal components analysis to derive three domains of neuropsychological functioning: 1) task-based executive function skills, 2) self-and emotion-regulation abilities, and 3) inhibitory control. Additionally, parents completed a home radon test kit and provided information on how long their child had lived in the tested home. We computed a radon exposure index per person based on the duration of time that the child had lived in the home and their measured home radon concentration. Youths were divided into terciles based on their radon exposure index score. Using a MANCOVA design, we determined whether there were differences in neuropsychological domain scores across the three groups, controlling for age, sex, and socioeconomic status.

Results

There was a significant multivariate effect of radon group on neuropsychological dysfunction (λ = 0.77, F = 2.32, p = 0.038, ηp2 = 0.12). Examination of univariate effects revealed specific increases in self-and emotion-regulation dysfunction among the youths with the greatest degree of chronic home radon exposure (F = 7.21, p = 0.002, ηp2 = 0.21). There were no significant differences by group in the other tested domains.

Discussion

The data suggest potential specificity in the neurotoxic effects of everyday home radon exposure in developing youths, with significant aberrations in self-and emotion-regulation faculties. These findings support the need for better public awareness and public health policy surrounding home radon safety and mitigation strategies.

The Toxicological Risk Assessment of Dermal Exposure of Patients Exposed to Lead and Cadmium Due to Application of Ointments with Marjoram Herb Extract (Majoranae herbae extractum)

Potential heavy metal impurities (HMI) in pharmaceuticals/pharmaceutical products/drugs based on plant raw materials (e.g., herbs) are an important problem in the pharmaceutical industry; however, there is a lack of scientific articles on the comprehensive toxicological risk assessment of HMI in ointment applied dermally. To make the appropriate toxicological risk assessment, we consider: (1) the raw results of the levels of lead and cadmium in the ointments (metal per kg of mass), (2) one-time administration of the applied ointment, (3) daily exposure of Pb and Cd in the applied ointments according to the maximum daily dose of applied pharmaceuticals, including transcutaneous penetration, (4) human health risk assessment based on the USEPA model, and 5) the margin of exposure (MoE). The raw results indicated that lead (7.05-101.78 µg/kg) and cadmium (0.32-0.81 µg/kg) were present in all samples. The levels of analyzed HMI (independently of the producer and declared composition) were similar. Pb and Cd contamination associated with daily doses met the standards of the ICH Q3D (R2) guide on elemental impurities in pharmaceuticals, including the cutaneous route of administration. Taking into account the daily amount of lead and cadmium (ointment, ug/day) the results were satisfactory, confirming the safety of marjoram herb extract ointments available in Polish pharmacies according to the ICH guideline Q3D (R2) on elemental impurities. The HQ values obtained for Pb and Cd in all samples were less than 1; therefore, exposure to these HMI would not cause a health risk based on the USEPA model strategy. Furthermore, the obtained values of MoE for Pb and Cd in ointments were above 100, so exposure to these elements would not cause a health risk based on the MoE-based strategy. The original contribution of this work is that this is the first study on the triple approach strategy to evaluate the safety of heavy metal impurities in traditional herbal medicinal products applied dermally in solid form (ointments with marjoram herb extract). The research is novel and has not been previously published; The proposed procedure includes transcutaneous penetration of heavy metal (Pb and Cd) impurities described for the first time in the literature.

Reducing disease and death from Artisanal and Small-Scale Mining (ASM) - the urgent need for responsible mining in the context of growing global demand for minerals and metals for climate change mitigation

Artisanal and small-scale mining (ASM) takes place under extreme conditions with a lack of occupational health and safety. As the demand for metals is increasing due in part to their extensive use in 'green technologies' for climate change mitigation, the negative environmental and occupational consequences of mining practices are disproportionately felt in low- and middle-income countries. The Collegium Ramazzini statement on ASM presents updated information on its neglected health hazards that include multiple toxic hazards, most notably mercury, lead, cyanide, arsenic, cadmium, and cobalt, as well as physical hazards, most notably airborne dust and noise, and the high risk of infectious diseases. These hazards affect both miners and mining communities as working and living spaces are rarely separated. The impact on children and women is often severe, including hazardous exposures during the child-bearing age and pregnancies, and the risk of child labor. We suggest strategies for the mitigation of these hazards and classify those according to primordial, primary, secondary, and tertiary prevention. Further, we identify knowledge gaps and issue recommendations for international, national, and local governments, metal purchasers, and employers are given. With this statement, the Collegium Ramazzini calls for the extension of efforts to minimize all hazards that confront ASM miners and their families.

Climate Change, Conflict, and Resource Extraction: Analyses of Nigerian Artisanal Mining Communities and Ominous Global Trends

Background:

The 2010 lead poisoning outbreak that claimed the lives of more than 400 children in artisanal gold mining villages in Zamfara, Nigeria is the tragic result of high gold prices, a geologic anomaly, and processing of ores in residential areas. Today, these villages face a growing crisis related to conflict and climate change. While the situation in Zamfara is unparalleled in many ways, the interactions between climate change, conflict, and mining consistently overlap a global scale. The scope of this analysis extends beyond the Nigerian crisis.

Objectives:

Understanding the complexities of challenges faced in Zamfara provides insight into how these issues impact vulnerable communities globally, and which strategies should be considered to solve this wicked problem.

Methods:

Analysis of the relationships between climate change, conflict, and mining in Zamfara and globally via literature review and examination of current events in the Sahel region.

Findings:

Supporting healthy artisanal mining communities, as was prioritized in Zamfara, must be a focus of environmental, health, and mineral management policies. This includes the consideration of multiple environmental health challenges, the protection of vulnerable groups, government-supported formalization programs, and meaningful involvement of local leadership in developing, implementing, and sustaining intervention strategies to enshrine ASM as a poverty reduction, climate change adaptation strategy.

Conclusions:

Rapidly rising metal prices and demand will continue to fuel environmental health crises associated with mining. Given Africa’s growing role in the global mineral economy and the massive number of subsistence communities who will continue to be impacted by climate change, strategies that support responsible artisanal mining are both a necessity for preventing future health crises and an opportunity for promoting regional stability and peace.

Elevated Serum Pb, Ni, Cd, and Cr Levels and DNA Damage in Exfoliated Buccal Cells of Teenage Scavengers at a Major Electronic Waste Dumpsite in Lagos, Nigeria

This study investigated the levels of Pb, Ni, Cd, and Cr in the blood, and DNA damage in exfoliated buccal cavity of scavenging teenagers at Alaba International electronic market, Nigeria. One hundred and ninety-nine blood samples were collected from scavenging teenagers in Alaba International market (n = 95) and the control group (n = 104). Blood Pb, Ni, Cd, and Cr concentrations were analyzed using graphite furnace atomic absorption spectrometry. Genotoxicity assessment was through exfoliated buccal cell micronucleus assay, while questionnaire was used to collect data on factors that can contribute to the blood heavy metal levels. The blood Pb of scavenging teenagers from Alaba International market varied from 2.84 to 189.44 μg/L compared to the control group with a range of 0.01 to 4.21 μg/L. The blood Cd (range = 0.38-12.35 μg/L), Cr (range = 0.20-19.03 μg/L), and Ni (range = 0.24-21.01 μg/L) were higher significantly in the Alaba group compared to the control group (Cd: range = 0.00-0.96 μg/L; Cr: range = 0.01-0.72 μg/L; and Ni: range = 0.00-0.28 μg/L). Frequencies of micronucleus, karyolysis, and pycnosis in the exfoliated buccal cells in Alaba group also increased significantly compared with the control group. Spearman correlation analyses indicated a positive correlation between the blood Pb, Ni, Cd, and Cr and induced micronucleus in the buccal exfoliated cells. Furthermore, data showed a positive correlation between Pb, Ni, Cd, and Cr and the duration of scavenging of the teenagers. However, a negative correlation was observed between educational status and Pb, Ni, Cd, and Cr. E-waste indiscriminate disposal and primitive recycling processes may be responsible for the high blood heavy metal levels, and consequently an increased DNA damage in exfoliated buccal cells in scavenging teenagers at Alaba International market. Graphical Abstract.

Diethylnitrosamine aggravates cadmium-induced hepatorenal oxidative damage in prepubertal rats

The adverse health consequences of environmental, occupational, and dietary exposure to either diethylnitrosamine (DEN) or cadmium (Cd) have been widely investigated. However, because most environmental exposures to xenobiotics do not occur in isolation but in mixtures, the effects of simultaneous exposure to both DEN and Cd on hepatorenal function deserves investigation. The present study investigated the impact of 7 days oral co-exposure to 10 mg/kg body weight (b.w.) of DEN and 5 mg/kg b.w. of Cd on biomarkers of hepatic and renal functions, antioxidant defense systems, and oxidative stress indices in the liver and kidney of prepubertal rats. The results showed that the significant (p < 0.05) increases in the levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma glutamyl transferase, urea, and creatinine following separate administration of DEN and Cd to rats were further increased in the co-exposure group. Moreover, marked decreases in the activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase as well as glutathione levels following individual administration of DEN and Cd to rats were exacerbated in the co-exposure group. Further, the marked increase in the lipid peroxidation level and the histopathological lesions in the liver and kidney of rats treated with DEN or Cd alone were intensified in the co-exposure group These findings indicate that co-exposure to DEN and Cd elicited more severe hepatic and renal oxidative damage in the rats, thus suggesting a greater risk to humans who are co-exposed to them.

Radon in Schools: A Brief Review of State Laws and Regulations in the United States

Exposure to Radon, a colorless, naturally occurring radioactive gas, is one of leading causes of lung cancer, and may pose a significant long-term risk for school age children. We examined the regulations and statutes in each US state related to radon in schools to delineate key features of policies and discrepancies among states that may have public health implications. Search terms such as "radon", "school", "mitigation", "certification", "licensing", and "radon resistant new construction" were used to scan current statutes from each state legislature's website and regulations from official state government websites for relevant regulatory and statutory requirements concerning radon in schools. State regulations related to the testing, mitigation, and public dissemination of radon levels in schools are inconsistent and the lack of nationwide indoor radon policy for schools may result in unacceptably high radon exposure levels in some US schools. We highlight the features and discrepancies of state laws and regulations concerning radon in schools, and offer several constructive means to reduce risks associated with radon exposure in school children.

A Fluorescent Sensor Array Based on Heteroatomic Macrocyclic Fluorophores for the Detection of Polluting Species in Natural Water Samples

The development of a novel all-solid-state optical sensor array based on heteroatomic macrocyclic fluorophores (diaza-crown ether, metallocorrole and pyridinophans) for the photographic analysis of liquid media, is presented. The sensitivity of the new optical system toward a number of different species (cations: Li⁺, K⁺, Na⁺, NH4+, Mg²⁺, Ca²⁺, Co²⁺, Cu²⁺, Zn²⁺, Cd²⁺, Pb²⁺ and anions: NO2-, NO3-, Cl⁻, Br⁻, HCO3-) was evaluated both in single selective sensor mode and in multisensory arrangement. The satisfactory PLS1 regression models between sensor array optical response and analyte concentration were obtained for Cd²⁺, Cu²⁺, Zn²⁺, and NO2- ions in all the range of tested concentrations. Among these species the highest attention was focused onto detection of cadmium and nitrite ions, for which the detection limits, DL, estimated by 3σ method were found 0.0013 mg/L and 0.21 mg/L respectively, and these values are lower than the corresponding WHO guideline values of 0.003 mg/L (Cd²⁺) and 2 mg/L (NO2-). The suitability of the developed sensors implemented with familiar devices for signal acquisition (Light Emitting Diode, LED, as light source and a digital camera as a signal detector), and chemometric methods for data treatment to perform fast and low-cost monitoring of species under interest, in real samples of environmental importance, is demonstrated.

Second-hand smoke generated by combustion and electronic smoking devices used in real scenarios: Ultrafine particle pollution and age-related dose assessment

Aerosol measurements were carried out in a model room where both combustion (conventional and hand-rolled cigarettes, a cigar and tobacco pipe) and non-combustion (e-cigarette and IQOS®) devices were smoked. The data were used to estimate the dose of particles deposited in the respiratory systems of individuals from 3months to 21years of age using the multiple-path particle dosimetry (MPPD) model. Regardless of the smoking device, the highest doses were received by infants, which reached 9.88×10⁸particles/kg bw during a cigar smoking session. Moreover, 60% to 80% of the particles deposited in the head region of a 3-month-old infant were smaller than 100nm and could be translocated to the brain via the olfactory bulb. The doses due to second-hand smoke from electronic devices were significantly lower, below 1.60×10⁸particles/kg bw, than those due to combustion devices. Dosimetry estimates were 50% to 110% higher for IQOS® than for e-cigarettes.

Association of blood heavy metals with developmental delays and health status in children

The aim of this study was to evaluate the association of blood lead, mercury, and cadmium concentrations with developmental delays and to explore the association of these concentrations with the health status of children. This study recruited 89 children with developmental delays and 89 age- and sex-matched children with typical development. Their health status was evaluated using the Pediatric Quality of Life (PedsQL) Inventory for health-related quality of life (HRQOL) and the Pediatric Outcomes Data Collection Instrument for function. Family function was also evaluated. Blood lead, mercury, and cadmium concentrations were measured using inductively coupled mass spectrometry. The children with developmental delays had a considerably poorer HRQOL, lower functional performance and family function, and a higher blood lead concentration than those with typical development. The blood lead concentration had a significantly positive association with developmental delays [odds ratio (OR) = 1.54, p < 0.01] in a dose-response manner, and it negatively correlated with PedsQL scores (regression coefficient: −0. 47 to −0.53, p < 0.05) in all the children studied. The higher blood cadmium concentration showed a significantly positive association with developmental delays (OR = 2.24, for >1.0 μg/L vs. <0.6 μg/L, p < 0.05). The blood mercury concentration was not associated with developmental delays and health status.

Effects of long-term irrigation with untreated municipal wastewater on soil properties and crop quality

Irrigating crops with untreated wastewater leads to elevated concentrations of heavy metals both in soil and cultivated crops. The current study was designed to determine heavy metal (i.e., Pb, Cd, Cr, Cu, Ni, Zn, Hg) accumulation in Konya soils in selected nine sites irrigated with wastewater for over 40 years. Non-irrigated soil samples and soil samples irrigated with well water were taken as control samples. Transport of these pollutants to the wheat samples cultivated in the investigated site was also examined. The obtained results reveal that high alkaline properties and clay structure of Konya soil reduce the mobility of contaminants and cause accumulation in the top layer of soil. Intense effect of wastewater irrigation on soil EC was determined. The highest concentrations of Pb, Cr, Cu, Cd, Zn, Ni, and Hg in wastewater irrigated soil were 5.32, 37.1, 31.5, 11.4, 91.5, 134, and 0.34 mg kg(-1), respectively. Wastewater irrigated soils were strongly polluted by means of Cd (8.23-11.6 mg kg(-1)) and moderately to strongly polluted by means of Ni (47.7-134 mg kg(-1)), exceeding Maximum Admissible Concentrations for Trace Elements in Agricultural Soils and Sewage Sludge Regulation limit values of Turkey. Maximum concentrations found for Pb, Cr, Cu, Cd, Zn, and Ni in wastewater irrigated wheat grain were 8.44, 1.30, 9.10, n.d, 29.31, and 0.94 mg kg(-1), respectively. Besides, Hg was not detected in any samples of wheat grain. Based on the regulation of Turkish Food Codex, Pb contamination in wheat samples grown in the sampling site was evidenced.

Blood lead levels and associated factors among children in Guiyu of China: a population-based study

OBJECTIVES

Children's health problems caused by the electronic waste (e-waste) lead exposure in China remains. To assess children's blood lead levels (BLLs) in Guiyu of China and investigate risk factors of children's elevated BLLs in Guiyu.

MATERIAL AND METHODS

842 children under 11 years of age from Guiyu and Haojiang were enrolled in this population-based study during 2011-2013. Participants completed a lifestyle and residential environment questionnaire and their physical growth indices were measured, and blood samples taken. Blood samples were tested to assess BLLs. Children's BLLs between the two groups were compared and factors associated with elevated BLLs among Guiyu children were analyzed by group Lasso logistic regression model.

RESULTS

Children living in Guiyu had significant higher BLLs (7.06 µg/dL) than the quantity (5.89 µg/dL) of Haojiang children (P<0.05). Subgroup analyses of BLLs exceeding 10 µg/dL showed the proportion (24.80%) of high-level BLLs for Guiyu children was greater than that (12.84%) in Haojiang (P<0.05). Boys had greater BLLs than girls, irrespectively of areas (P<0.05). The number of e-waste piles or recycling workshops around the house (odds ratio, 2.28; 95% confidence interval [CI], 1.37 to 3.87) significantly contributed to the elevated BLLs of children in Guiyu, and girls had less risk (odds ratio, 0.51; 95% CI, 0.31 to 0.83) of e-waste lead exposure than boys.

CONCLUSIONS

This analysis reinforces the importance of shifting e-waste recycling piles or workshops to non-populated areas as part of a comprehensive response to e-waste lead exposure control in Guiyu. To correct the problem of lead poisoning in children in Guiyu should be a long-term mission.

Evaluation of lead levels in biological samples of mentally retarded children in different stages using advanced extraction method

In present study the lead (Pb) levels has been assessed by analyzing the scalp hair and blood samples of mentally retarded/intellectual disabled (MR/ID) children of both genders, age ranged 3-8 years. For comparative purpose, healthy age matched children were also selected. The cloud point extraction of Pb from digested biological samples was carried out by complexed with ammonium pyrrolidinedithiocarbamate. The complexed analyte was subsequently isolated from the aqueous matrix in the micelles of a non-ionic surfactant (Triton X-114). Dilution of the surfactant-rich phase with acidified ethanol was performed after phase separation, and the Pb content was measured by flame atomic absorption spectrometer. Factors affecting the cloud point extraction were evaluated and optimized. The proposed procedure allowed the determination of lead in certified standard and real samples with detection limits of 0.834μgL(-) and enhancement factor 55. The results were compared with those of healthy children have same age, socioeconomic status and residential areas.

A ferrocene-porphyrin ligand for multi-transduction chemical sensor development

5,10,15,20-Tetraferrocenyl porphyrin, H2TFcP, a simple example of a donor-acceptor system, was tested as ligand for the development of a novel multi-transduction chemical sensors aimed at the determination of transition metal ions. The fluorescence energy transfer between ferrocene donor and porphyrin acceptor sub-units was considered. The simultaneously measured optical and potentiometric responses of solvent polymeric membranes based on H2TFcP permitted the detection of lead ions in sample solutions, in the concentration range from 2.7 × 10(-7) to 3.0 × 10(-3) M. The detection limit of lead determination was 0.27 μM, low enough to perform the direct analysis of Pb2+ in natural waters.

The influence of environmental exposure on lead concentrations in scalp hair of children in Pakistan

In the present study the environmental and occupational exposure of Pb has been assessed by analyzing the scalp hair (SH) of children (both genders), residing in the vicinity of industrial area of Hyderabad, Pakistan. A total of 339 children attending primary schools situated in the industrial area, age ranged 5-10 years, while for comparative purpose children of the same age group from schools located in an area devoid of industries, were selected. The scalp hair was oxidized by acid mixture in a microwave oven prior to determination of Pb by graphite furnace atomic absorption spectrometry. The concentration profile of Pb in SH of children showed that the level changed significantly (44-64%) with changes of living habits or environmental exposure. The influence of age, sex, and family occupation on the children's hair Pb concentration was also evaluated. Significant differences in SH-Pb levels were observed between the exposed (EXC) and non-exposed (NEC) children (p<0.01). The concentration of Pb in boys of exposed (EX) and non-exposed (NEX) area was more than in girls of the corresponding localities. The boys and girls of NEX and EX areas have SH-Pb in the range of 3.97-5.4 and 6.06-13.7 μg g(-1) and 3.41-7.4 and 5.56-11.5 μg g(-1), respectively. The Pb levels increased with age in both study groups.

Assessment of DNA damage by RAPD in Paracentrotus lividus embryos exposed to amniotic fluid from residents living close to waste landfill sites

The aim of this study was to assess the genotoxic effects of environmental chemicals on residents living near landfills. The study was based on samples of amniotic fluid from women living in the intensely polluted areas around the Campania region of Italy compared to a nonexposed control group. We evaluated the genetic effects that this amniotic fluids collected in contaminated sites had on Paracentrotus lividus embryos. DNA damage was detected through changes in RAPD (Random Amplified Polymorphism DNA) profiles. The absence of the amplified DNA fragments indicated deletions in Paracentrotus lividus DNA exposed to the contaminated amniotic fluids when compared to equal exposure to uncontaminated fluids. These results show the ability of RAPD-PCR to detect and isolate DNA sequences representing genetic alterations induced in P. lividus embryos. Using this method, we identified two candidate target regions for DNA alterations in the genome of P. lividus. Our research indicates that RAPD-PCR in P. lividus embryo DNA can provide a molecular approach for studying DNA damage from pollutants that can impact human health. To our knowledge, this is the first time that assessment of DNA damage in P. lividus embryos has been tested using the RAPD strategy after exposure to amniotic fluid from residents near waste landfill sites.

Blood lead and cadmium levels and relevant factors among children from an e-waste recycling town in China

BACKGROUND

Primitive electronic waste (e-waste) recycling is ongoing in Guiyu, and thus toxic heavy metals may keep on threatening to the health of local children. Some related factors may contribute to the elevation of blood lead levels (BLLs) or blood cadmium levels (BCLs).

OBJECTIVE

To investigate the children's BLLs and BCLs in Guiyu and Chendian as compare to discuss the effects of primitive e-waste recycling activities on children's health.

METHODS

Two hundred and seventy-eight children less than 8 years who lived in Guiyu and Chendian were observed, and their BLLs and BCLs were determined by graphite atomizer absorption spectrophotometer. Questionnaire survey for risk factors was also performed and data were analyzed using spearman correlation analyses and logistic regression analyses.

RESULTS

Children living in Guiyu had significantly higher BLLs and BCLs as compared with those living in Chendian (p<0.01). In Guiyu, 70.8% of children (109/154) had BLLs>10 microg/dL, and 20.1% of children (31/154) had BCLs>2 microg/L, compared with 38.7% of children (48/124) had BLLs>10 microg/dL and 7.3% of children (9/124) had BCLs>2 microg/L in Chendian (p<0.01, respectively). We also observed a significant increasing trend in BLLs with increasing age in Guiyu (p<0.01). Mean height of children in Guiyu was significantly lower than that in Chendian (p<0.01). The risk factors related to children's BLLs and BCLs mainly included father's engagement in the work related to e-waste, children's residence in Guiyu and the amount of time that children played outside near the road everyday.

CONCLUSIONS

There are close relationships between the BLLs, BCLs in children and the primitive e-waste recycling activities in Guiyu. Environmental pollution, especially lead pollution, has threatened the health of children living around e-waste recycling site.

Electrochemical sensors for the detection of lead and other toxic heavy metals: the next generation of personal exposure biomonitors

To support the development and implementation of biological monitoring programs, we need quantitative technologies for measuring xenobiotic exposure. Microanalytical based sensors that work with complex biomatrices such as blood, urine, or saliva are being developed and validated and will improve our ability to make definitive associations between chemical exposures and disease. Among toxic metals, lead continues to be one of the most problematic. Despite considerable efforts to identify and eliminate Pb exposure sources, this metal remains a significant health concern, particularly for young children. Ongoing research focuses on the development of portable metal analyzers that have many advantages over current available technologies, thus potentially representing the next generation of toxic metal analyzers. In this article, we highlight the development and validation of two classes of metal analyzers for the voltammetric detection of Pb, including: a) an analyzer based on flow injection analysis and anodic stripping voltammetry at a mercury-film electrode, and b) Hg-free metal analyzers employing adsorptive stripping voltammetry and novel nanostructure materials that include the self-assembled monolayers on mesoporous supports and carbon nanotubes. These sensors have been optimized to detect Pb in urine, blood, and saliva as accurately as the state-of-the-art inductively coupled plasma-mass spectrometry with high reproducibility, and sensitivity allows. These improved and portable analytical sensor platforms will facilitate our ability to conduct biological monitoring programs to understand the relationship between chemical exposure assessment and disease outcomes.

Elevated blood lead levels of children in Guiyu, an electronic waste recycling town in China

BACKGROUND

Electronic waste (e-waste) recycling has remained primitive in Guiyu, China, and thus may contribute to the elevation of blood lead levels (BLLs) in children living in the local environment.

OBJECTIVES

We compared the BLLs in children living in the e-waste recycling town of Guiyu with those living in the neighboring town of Chendian.

METHODS

We observed the processing of e-waste recycling in Guiyu and studied BLLs in a cluster sample of 226 children < 6 years of age who lived in Guiyu and Chendian. BLLs were determined with atomic absorption spectrophotometry. Hemoglobin (Hgb) and physical indexes (height and weight, head and chest circumferences) were also measured.

RESULTS

BLLs in 165 children of Guiyu ranged from 4.40 to 32.67 microg/dL with a mean of 15.3 microg/dL, whereas BLLs in 61 children of Chendian were from 4.09 to 23.10 microg/dL with a mean of 9.94 microg/dL. Statistical analyses showed that children living in Guiyu had significantly higher BLLs compared with those living in Chendian (p < 0.01). Of children in Guiyu, 81.8% (135 of 165) had BLLs > 10 microg/dL, compared with 37.7% of children (23 of 61) in Chendian (p < 0.01). In addition, we observed a significant increasing trend in BLLs with increasing age in Guiyu (p < 0.01). It appeared that there was correlation between the BLLs in children and numbers of e-waste workshops. However, no significant difference in Hgb level or physical indexes was found between the two towns.

CONCLUSIONS

The primitive e-waste recycling activities may contribute to the elevated BLLs in children living in Guiyu.

Environmental lead toxicity and nutritional factors

Environmental lead toxicity is an old but persistent public health problem throughout the world and children are more susceptible to lead than adults because of their hand to mouth activity, increased respiratory rates and higher gastrointestinal absorption per unit body weight. In the last decade children's blood lead levels have fallen significantly in a number of countries. Despite this reduction, childhood lead toxicity continues to be a major public health problem for certain at-risk groups of children, and concern remains over the effects of lead on intellectual development. The currently approved clinical intervention method is to give chelating agents, which bind and removed lead from lead burdened tissues. Studies indicate, however, that there is a lack of safety and efficacy when conventional chelating agents are used. Several studies are underway to determine the beneficial effect of nutrients supplementation following exposure to lead. Data suggest that nutrients may play an important role in abating some toxic effects of lead. To explain the importance of using exogenous nutrients in treating environmental lead toxicity the following topics are addressed: (i) different sources of lead exposure/current blood lead levels and (ii) protective effects of nutrients supplementation (some essential elements and vitamins) in lead toxicity.

Exposição ambiental a interferentes endócrinos com atividade estrogênica e sua associação com distúrbios puberais em crianças

A substância exógena que causa efeitos adversos na saúde de um organismo ou sua descendência, como resultado de distúrbios na função hormonal, é denominada interferente endócrino. Nos últimos anos, produtos ambientais com atividades hormonais têm sido documentados como causadores de anormalidades puberais ou reprodutivas em animais. Os poucos casos comprovados em humanos foram aqueles relacionados a exposições acidentais. Apesar disso, pediatras e pais recomendam a suspensão de todos os alimentos potencialmente contaminados, em especial carne (aves, gado) e derivados da soja quando a criança apresenta alguma alteração puberal. Estas recomendações, se não embasadas cientificamente, podem ter conseqüências deletérias, não apenas pela eliminação de fontes protéicas da dieta, como também por retardar a investigação de causas tratáveis. Por outro lado, a não investigação dos efeitos adversos destes produtos é da mesma forma danosa. Esta revisão descreve os principais interferentes endócrinos responsáveis por alterações puberais em humanos e conclui que, excetuando exposições acidentais a altas quantidades destes produtos, mais estudos são necessários para responsabilizar a ação crônica e em baixas doses destas substâncias na alteração do tempo de desenvolvimento puberal em nossa espécie.

Questionnaire survey of exposure to lead in the domestic environment in Nigeria

Environmental exposure to lead is a significant cause of morbidity and mortality in developed countries, particularly in children, but remains understudied in developing countries. While prevention is acknowledged as the best public health option, the level of knowledge about lead exposure in many developing countries is not known. We conducted a survey to evaluate the knowledge about lead exposure in Nigeria. Survey questionnaires were developed from the results of focus group discussions and published literature. 600 questionnaires were randomly distributed to adults living in Ibadan, South Western Nigeria in 2004. In addition, the knowledge of lead exposure was measured using a modified version of the Chicago Lead Knowledge Test (CLKT). Information on lead abatement and sources of household lead exposure were also obtained. Most respondents did not have a satisfactory level of knowledge about lead exposure in the domestic environment, how to prevent it and the role of nutrition in diminishing the impact of exposure. Younger people, female and increased years of schooling predict higher scores in the CLKT. Most respondents lived in rented homes; the majority of which were either built or last refurbished in the 1990s. Home owners and people living in homes built or last refurbished within 4 years of the study had higher mean CLKT scores. Our study showed that our respondents had very low levels of knowledge about the risk of domestic exposure to lead, particularly to children. We recommend that efforts should be made to increase awareness of this condition and that in Nigeria as in most development countries; this should be done through the maternal and child health care programs.

Paediatric transfusion

The requirements of children undergoing transfusion should be considered as a distinct entity from those of adults. Neonates are particularly vulnerable and there have been concerns over infective or toxic risks to this group. Neonates may also have more acute side-effects as a result of their small blood volume. Most children who are transfused will have a good life expectancy, so long-term side-effects will be more significant than for adults. In Britain, there are a number of transfusion components with neonatal specifications, but there appears to be some confusion, among both medical and laboratory staff, as to the appropriate use of these. Although there are many paediatric guidelines on the use of blood, there is a lack of evidence underlying these. However, there are trends to decreased blood usage in neonates and ongoing studies to investigate the appropriate use of blood for children.

Childhood lead exposure in the palestinian authority, Israel, and Jordan: results from the Middle Eastern regional cooperation project, 1996-2000

In the Middle East, the major sources of lead exposure have been leaded gasoline, lead-contaminated flour from traditional stone mills, focal exposures from small battery plants and smelters, and kohl (blue color) in cosmetics. In 1998-2000, we measured blood lead (PbB) levels in children 2-6 years of age in Israel, Jordan, and the Palestinian Authority (n = 1478), using a fingerstick method. Mean (peak; percentage > 10 microg/dL) PbB levels in Israel (n = 317) , the West Bank (n = 344), Jordan (n = 382) , and Gaza (n = 435) were 3.2 microg/dL (18.2 ; 2.2%) , 4.2 microg/dL (25.7; 5.2%), 3.2 microg/dL (39.3; < 1%) , and 8.6 microg/dL (> 80.0; 17.2%), respectively. High levels in Gaza were all among children living near a battery factory. The findings, taken together with data on time trends in lead emissions and in PbB in children in previous years, indicate the benefits from phasing out of leaded gasoline but state the case for further reductions and investigation of hot spots. The project demonstrated the benefits of regional cooperation in planning and carrying out a jointly designed project.

Recent developments in low-level lead exposure and intellectual impairment in children

In the last decade children's blood lead levels have fallen significantly in a number of countries, and current mean levels in developed countries are in the region of 3 Mu g/dL. Despite this reduction, childhood lead poisoning continues to be a major public health problem for certain at-risk groups of children, and concerns remain over the effects of lead on intellectual development in infants and children. The evidence for lowered cognitive ability in children exposed to lead has come largely from prospective epidemiologic studies. The current World Health Organization/Centers for Disease Control and Prevention blood level of concern reflects this and stands at 10 Mu g/dL. However, a recent study on a cohort of children whose lifetime peak blood levels were consistently less than 10 Mu g/dL has extended the association of blood lead and intellectual impairment to lower levels of lead exposure and suggests there is no safety margin at existing exposures. Because of the importance of this finding, we reviewed this study in detail along with other recent developments in the field of low-level lead exposure and children's cognitive development. We conclude that these findings are important scientifically, and efforts should continue to reduce childhood exposure. However, from a public health perspective, exposure to lead should be seen within the many other risk factors impacting on normal childhood development, in particular the influence of the learning environment itself. Current lead exposure accounts for a very small amount of variance in cognitive ability (1-4%), whereas social and parenting factors account for 40% or more.