Weiqiu Li

Association between lead exposure from electronic waste recycling and child temperament alterations

We aimed to evaluate the dose-dependent effects of lead exposure on temperament alterations in children from a primitive e-waste (obsolete electrical and electronic devices) recycling area in Guiyu of China and a control area (Chendian, China). Blood lead levels (BLL) might be correlated with temperament, health, and relevant factors that were evaluated through Parent Temperament Questionnaire (PTQ), physical examination, and residential questionnaires. We collected venipuncture blood samples from 303 children (aged 3-7 years old) between January and February 2008. Child BLL were higher in Guiyu than in Chendian (median 13.2 μg/dL, range 4.0-48.5 μg/dL vs. 8.2 μg/dL, 0-21.3 μg/dL) (P<0.01). Significant differences of mean scores in activity level (4.53±0.83 vs. 4.18±0.81), approach-withdrawal (4.62±0.85 vs. 4.31±0.89), and adaptability (4.96±0.73 vs. 4.67±0.83) were found between Guiyu and Chendian children (all P<0.01). High BLL (BLL≥10μg/dL) child had higher mean scores of approach-withdrawal when compared with those children with low BLL (BLL<10 μg/dL) (4.61±0.87 vs. 4.30±0.88, P<0.01). Location of child residence in Guiyu, and parents engagement in work related to e-waste were the risk factors related to child BLL, activity level, approach-withdrawal, adaptability, and mood. Child hand washing prior to food consumption was a protected factor for BLL and several dimensions. There are close relationships between BLL elevation, temperament alteration and the e-waste recycling activities in Guiyu. Primitive e-waste recycling may threaten the health of children by increasing BLL and altering children temperament, although the exposure to other toxicants needs to be examined in future studies.

Association of MDR1 and ERCC1 polymorphisms with response and toxicity to cisplatin-based chemotherapy in non-small-cell lung cancer patients

Among the cancer patient population, resistance to therapy is a major cause for therapeutic failure and for human sufferings, especially for the cancer with poor prognosis. Therefore, finding factors that contribute to drug resistance is a major research interest. In this study, we have investigated whether polymorphisms in genes that control import/export of drugs (MDR1) and that repair DNA adducts (ERCC1) are involved with drug resistance in non-small cell lung cancer (NSCLC) patients. We have recruited 95 patients with advanced NSCLC (stages IIIB-IV) who were specifically treated with platinum-based chemotherapy. We used the ligase detection reactions assay (LDR) to detect polymorphisms in ERCC1 118C/T, and MDR1 2677T/A, E1/-129T/C, and C3435T in peripheral blood lymphocytes from the patients. The haplotype of MDR1 gene single nucleotide polymorphisms (SNPs) were analyzed using the SHEsis software platform on line. We found that none of the single polymorphisms was associated with treatment response or related toxicity. However, patients carrying at least one variant MDR1 2677 T allele was associated with a significantly increased risk of drug resistance (OR=1.844, 95% CI=1.01-3.53, P=0.04) but also with a significantly increased risk of gastrointestinal toxicity (P=0.03) but not hemato-, hepato- or nephro-toxicities. Moreover, we analyzed the haplotypes of the three polymorphisms in MDR1. The patients harboring the E1/-129T-2677T-3435C haplotype had a significantly better response to chemotherapy compared with those having the other haplotypes (P=0.02, 95% CI=1.20-25.87), and a marginally significant association with increased risk of gastrointestinal toxicity (P=0.02, 95% CI=1.15-3.88). Our results suggested that gene polymorphisms in MDR1G2677T/A may be a predictive marker of platinum-based treatment response and of secondary effects, especially gastrointestinal toxicity for advanced NSCLC patients.

Polybrominated diphenyl ethers in residential and agricultural soils from an electronic waste polluted region in South China: Distribution, compositional profile, and sources

A detailed investigation was conducted to understand the concentration, distribution, profile and possible source of polybrominated diphenyl ethers (PBDEs) in residential and agricultural soils from Guiyu, Shantou, China, one of the largest electronic waste (e-waste) recycling and dismantling areas in the world. Ten PBDEs were analyzed in 46 surface soil samples in terms of individual and total concentrations, together with soil organic matter concentrations. Much higher concentrations of the total PBDEs were predicted in the residential areas (more than 2000 ng g(-1)), exhibiting a clear urban source, while in the agricultural areas, concentrations were lower than 1500 ng g(-1). PBDE-209 was the most dominant congener among the study sites, indicating the prevalence of commercial deca-PBDE. However signature congeners from commercial octa-PBDE were also found. The total PBDE concentrations were significantly correlated with each individual PBDE. Principal component analysis indicated that PBDEs were mainly distributed in three groups according to the number of bromine atoms on the phenyl rings, and potential source. This study showed that the informal e-waste recycling has already introduced PBDEs into surrounding areas as pollutant which thus warrants an urgent investigation into the transport of PBDEs in the soil-plant system of agricultural areas.

Downregulation of placental S100P is associated with cadmium exposure in Guiyu, an e-waste recycling town in China.

Excessive release of heavy metals, especially cadmium (Cd) and lead (Pb), results from primitive electronic waste (e-waste) recycling activities in Guiyu, China, and has adverse effects on the health of local infants and pregnant women. We investigated the expression of placental S100P, a Ca(2+)-binding protein, as a biological indicator of heavy-metal environmental pollution in pregnant women involved in these activities and constantly exposed to Cd and Pb. We included 105 pregnant women in the study: 55 from Guiyu and 50 from Shantou, an area not involved in e-waste recycling. The placental concentrations of Cd and Pb (PCCd, PCPb) after birth were measured by graphite-furnace atomic-absorption spectrometry. S100P mRNA expression was determined by semi-quantitative RT-PCR and real-time quantitative PCR. S100P protein expression was examined by western blot analysis and immunohistochemistry. The expression of metallothionein (MT), previously found upregulated after heavy metal contamination, was used for comparison. Placentas from Guiyu women showed 62.8% higher Cd concentrations, higher MT levels, and lower S100P protein levels than placentas from Shantou women. Furthermore, PCCd was negatively correlated with S100P protein expression and positively with MT expression, with no correlation between PCPb and S100P or MT expression. The PCCd-associated downregulation of S100P in placentas from Guiyu women suggests that S100P might be an effective biological indicator in the placental response to Cd toxicity in areas of e-waste recycling.

Associations between maternal phenolic exposure and cord sex hormones in male newborns

STUDY QUESTION Are maternal urinary phenol concentrations associated with cord steroid hormone levels and anogenital distance (AGD) in male newborns? SUMMARY ANSWER High maternal urinary Bisphenol A (BPA) levels are associated with decreases in cord testosterone levels and the ratio of testosterone to estradiol in male newborns, but there was no significant association with AGD. WHAT IS KNOWN ALREADY Early life exposure to phenolic endocrine disrupting compounds (EDCs) is known to disrupt hormonal activities and affect reproductive development in males. However, studies on the health effects of prenatal human exposure are scarce. STUDY DESIGN, SIZE, DURATION This was a cross-sectional study to investigate the association between maternal phenolic exposure and cord sex steroid hormones and AGD in male newborns. We recruited 100 mother-infant pairs from each of two hospitals, one in a polluted town (Guiyu) and the other in a cleaner town (Haojiang), from September 2010 to September 2011. PARTICIPANTS/MATERIALS, SETTING, METHODS One hundred and seventy eight maternal urine samples and 137 cord blood samples were available for quantification, thus 137 complete records entered into the final analysis. Of them, 77 pairs were from Guiyu, and 60 were from Haojiang. The chemical concentrations were determined by solid phase extraction and gas chromatography-mass spectrometry (SPE-GC-MS), and cord sex hormones were detected by radioimmunoassay (RIA). Neonatal anthropometric parameters including AGD were measured. MAIN RESULTS AND THE ROLE OF CHANCE Log2-transformed maternal urinary BPA concentration was negatively correlated with testosterone level and the ratio of testosterone to estradiol (T/E2) in male fetal cord blood after adjustment for potential confounders in linear regression models (βadjusted = -31.09 (95% CI, -53.07 to -9.11) and βadjusted = -0.08 (95% CI, -0.13 to -0.01), respectively). Moreover, compared with the lowest quartile group of BPA level, the highest group showed a significant decrease in testosterone level and T/E2 (βadjusted = -179.84 (95% CI, -333.45 to -26.24) and βadjusted = -0.37 (95% CI, -0.81 to 0.07), respectively). No significant associations between AGD or anogenital index (AGI, [AGI = AGD/birthweight (mm/kg)]) and phenolic EDCs or cord hormone levels were found. LIMITATIONS, REASONS FOR CAUTION Results in the present study should be interpreted with caution because of its cross-sectional nature, small sample size and sampling time. WIDER IMPLICATIONS OF THE FINDINGS Testosterone plays an important role in sex differentiation and normal development of the fetus and newborn, and the balance between testosterone and estradiol is thought an important mediator of prostate disease. Therefore, our findings may have important implications for human reproductive health. STUDY FUNDING/COMPETING INTERESTS This work was supported by the National Natural Science Foundation of China (21377077) and Guangdong University Project for International Cooperation and Innovation Platform (2013gjhz0007). The authors declare they have no actual or potential competing financial interests.

Chromium exposure among children from an electronic waste recycling town of China

Guiyu is one of the most heavily chromium-polluted areas in China due to the numerous informal electronic waste (e-waste) recycling activities. A 3-year (2004, 2006, and 2008) independent cross-sectional study on blood chromium (BCr) levels of 711 children from Guiyu and a control area was investigated. Questionnaire completed by parents/guardians was used to assess the risk factors of chromium (Cr) exposure, while physical examination, for the year 2008 only, was used to evaluate the effects of long-term exposure to Cr on child physical development. Children living in Guiyu had significantly higher BCr levels compared with those living in Chendian at the same period from 2004 to 2008 (P < 0.001). The predominant risk factors related to elevated child BCr levels included the use of house as a family workshop, parent involved in e-waste recycling, and child residence in Guiyu. Children’s weight and chest circumferences in group with high exposure to Cr (upper quartile) were higher than in the low-exposure group (P < 0.01), although the difference was less significant for boys between the two groups (P < 0.05). The results suggest that elevated child BCr in Guiyu due to informal e-waste recycling activities might be threatening the health of children, with implications on physical growth and development.

Considerable decrease of antibody titers against measles, mumps, and rubella in preschool children from an e-waste recycling area

Data on vaccination effects in children chronically exposed to heavy metals are extremely scarce. This study aims to investigate the immune responsiveness to measles, mumps, and rubella (MMR) vaccination in children from an e-waste recycling area. 378 healthy children from Guiyu (exposed group) and Haojiang (reference group) were surveyed. Blood lead (Pb) levels were measured by graphite furnace atomic absorption. Titers of antibodies against MMR were quantified by ELISA. Blood Pb levels of children from the exposed group were significantly higher than those from the reference group (5.61μg/dL vs. 3.57μg/dL, p<0.001). In contrast, the antibody titers against MMR of the children from the exposed group were significantly lower than those from the reference group. The median titer of the anti-measles antibody of the exposed group was 669.64mIU/mL, with an interquartile range of 372.88-1068.42mIU/mL; this was decreased by nearly 40% compared to that of the reference group (median 1046.79mIU/mL, interquartile range 603.29-1733.10mIU/mL). For antibody titers against mumps, there was an about 45% decrease in the exposed group (median 272.24U/mL, interquartile range 95.19-590.16U/mL), compared to the reference group (median 491.78U/mL, interquartile range 183.38-945.96U/mL). In the case of rubella, the median titer of the antibody was also significantly lower in the exposed group (median 37.08IU/mL, interquartile range 17.67-66.66IU/mL) compared to the reference group (median 66.50IU/mL, interquartile range 25.32-105.59IU/mL); the decrease in this case was nearly 44%. The proportion of children whose antibody titers against MMR were below protective level in the exposed group was higher than it was in the reference group. The present study demonstrates that the immune responsiveness to routine vaccination was suppressed in children chronically exposed to lead. Thus, the vaccination strategies for these children living in an e-waste recycling area should be modified.

Chaotic time series prediction for prenatal exposure to polychlorinated biphenyls in umbilical cord blood using the least squares SEATR model.

Chaotic time series prediction based on nonlinear systems showed a superior performance in prediction field. We studied prenatal exposure to polychlorinated biphenyls (PCBs) by chaotic time series prediction using the least squares self-exciting threshold autoregressive (SEATR) model in umbilical cord blood in an electronic waste (e-waste) contaminated area. The specific prediction steps basing on the proposal methods for prenatal PCB exposure were put forward, and the proposed scheme’s validity was further verified by numerical simulation experiments. Experiment results show: 1) seven kinds of PCB congeners negatively correlate with five different indices for birth status: newborn weight, height, gestational age, Apgar score and anogenital distance; 2) prenatal PCB exposed group at greater risks compared to the reference group; 3) PCBs increasingly accumulated with time in newborns; and 4) the possibility of newborns suffering from related diseases in the future was greater. The desirable numerical simulation experiments results demonstrated the feasibility of applying mathematical model in the environmental toxicology field.

Actin cytoskeleton reorganization correlates with polarization of secretory vesicle and cell morphology in the degranulation of mast cell subtypes in human colon tissues.

Mast cells play a central role in the intestinal immune response. To investigate the relationship between degranulation, cell polarization and the reorganization of actin cytoskeleton of mast cells, we used fluorescence or gold labeling methods to identify different mast cell subtypes in human colon. The reorganization of filamentous actin was visualized and then the polarization of secretory vesicles, as well as cell surfaces, was analyzed by fluorescence microscopy and electron microscopy. Our results first showed a diversity of filamentous actin assembly or disassembly within the contacting cell membrane of different mast cell subtypes. The polarization and degranulation of secretory vesicles was not only accompanied with the assembly and disassembly of filamentous actin at the cell periphery, but also with changes of cell surface polarization. Our study provides an insight into the local membranous structures and suggested correlations of cytoskeleton arrangement with the polarization of secretory vesicles and cell surface configuration during mast cell degranulation.