Effects of perinatal exposure to PCBs and dioxins on play behavior in Dutch children at school age

Polychlorinated biphenyls (PCBs) and dioxins are known as neurotoxic compounds that may modulate sex steroid hormones. Steroid hormones play a mediating role in brain development and may influence behaviors that show sex differences, such as childhood play behavior. In this study we evaluated the effects of perinatal exposure to environmental levels of PCBs and dioxins on childhood play behavior and whether the effects showed sex differences. As part of the follow-up to the Dutch PCB/dioxin study at school age, we used the Pre-School Activity Inventory (PSAI) to assess play behavior in the Rotterdam cohort (n = 207). The PSAI assesses masculine or feminine play behavior scored on three subscales: masculine, feminine, and composite. Prenatal exposure to PCBs was defined as the sum of PCB 118, 138, 153, and 180 in maternal and cord plasma and breast milk. For breast milk we measured additional PCBs as well as 17 dioxins. Respondents returned 160 questionnaires (age 7.5 years +/- 0.4). Effects of prenatal exposure to PCBs, measured in maternal and cord plasma, on the masculine and composite scales were different for boys and girls (p <.05). In boys, higher prenatal PCB levels were related with less masculinized play, assessed by the masculine scale (p(maternal) =.042; p(cord) =.001) and composite scale (p(cord) =.011), whereas in girls higher PCB levels were associated with more masculinized play, assessed by the composite scale (p(PCBmilk) =.028). Higher prenatal dioxin levels were associated with more feminized play in boys as well as girls, assessed by the feminine scale (p =.048). These effects suggest prenatal steroid hormone imbalances caused by prenatal exposure to environmental levels of PCBs, dioxins, and other related organochlorine compounds.     

Persistent and serious lack of data on chronic disorders in Dutch children

A recent report summarizes the available knowledge on chronic disorders in children in The Netherlands. There is a striking lack of high-quality data on the prevalence of common disorders such as attention deficit hyperactivity disorder (ADHD), atopic eczema, and abdominal pain. Reliable prevalence figures were available for only 34 out of a total of 284 chronic disorders. These affected a total of 4% of all children in the general population--the real prevalence ofchronic disease in children must be considerably higher. There is an even greater lack of studies on the impact of chronic disorders in childhood on quality of life and social and emotional well-being in later life.     

围生期暴露与儿童支气管哮喘相关性的研究进展

支气管哮喘是一种以慢性气道炎症和气道高反应性为特征的异质性疾病,我国儿童支气管哮喘的患病率呈逐年上升趋势,总体控制水平仍不理想。越来越多的证据表明,在生命早期发生的负面事件,甚至在围生期,会显著增加生命后期哮喘和肺功能不良的风险。本文就围生期暴露与儿童支气管哮喘相关性的研究现状进行综述。     

Prenatal exposure to organophosphate pesticides and IQ in 7-year-old children

Context: Organophosphate (OP) pesticides are neurotoxic at high doses. Few studies have examined whether chronic exposure at lower levels could adversely affect children’s cognitive development.Objective: We examined associations between prenatal and postnatal exposure to OP pesticides and cognitive abilities in school-age children.Methods: We conducted a birth cohort study (Center for the Health Assessment of Mothers and Children of Salinas study) among predominantly Latino farmworker families from an agricultural community in California. We assessed exposure to OP pesticides by measuring dialkyl phosphate (DAP) metabolites in urine collected during pregnancy and from children at 6 months and 1, 2, 3.5, and 5 years of age. We administered the Wechsler Intelligence Scale for Children, 4th edition, to 329 children 7 years of age. Analyses were adjusted for maternal education and intelligence, Home Observation for Measurement of the Environment score, and language of cognitive assessment.Results: Urinary DAP concentrations measured during the first and second half of pregnancy had similar relations to cognitive scores, so we used the average of concentrations measured during pregnancy in further analyses. Averaged maternal DAP concentrations were associated with poorer scores for Working Memory, Processing Speed, Verbal Comprehension, Perceptual Reasoning, and Full-Scale intelligence quotient (IQ). Children in the highest quintile of maternal DAP concentrations had an average deficit of 7.0 IQ points compared with those in the lowest quintile. However, children’s urinary DAP concentrations were not consistently associated with cognitive scores.Conclusions: Prenatal but not postnatal urinary DAP concentrations were associated with poorer intellectual development in 7-year-old children. Maternal urinary DAP concentrations in the present study were higher but nonetheless within the range of levels measured in the general U.S. population.     

Serum dioxin and immunologic response in veterans of Operation Ranch Hand.

The authors studied immune response and exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (dioxin) among veterans of Operation Ranch Hand, the US Air Force unit responsible for the aerial spraying of herbicides in Vietnam from 1962 to 1971. A comparison group of Air Force veterans who served in Southeast Asia but were not involved in spraying herbicides was included. The authors studied delayed-type hypersensitivity skin test responses to Candida albicans, mumps, Trichophyton, and a bacterial antigen made from lysed Staphylococcus aureus. Lymphocyte measurements included total lymphocyte counts; T-cell (CD3, CD4, CD5, and CD8), B-cell (CD20), and NK-cell (CD16 and CD56) subsets; and expression of the activation antigen CD25 on CD3 T cells. The authors quantitated the serum concentrations of immunoglobulin (Ig)A, IgG, and IgM; examined sera for the presence of monoclonal immunoglobulins (M proteins); and looked for a broad range of autoantibodies (rheumatoid factor, antinuclear antibody, smooth muscle autoantibody, mitochondrial autoantibody, parietal cell autoantibody, and thyroid microsomal autoantibodies). They measured the level of dioxin in 1987 or 1992, extrapolated the result to the time of service in Vietnam, and assigned each veteran to one of four exposure categories: Comparison and three Ranch Hand groups (Background, Low, or High). Overall, the authors found no evidence of a consistent relation between dioxin exposure category and immune system alteration.     

Immunologic effects of background exposure to polychlorinated biphenyls and dioxins in Dutch preschool children

Prenatal exposure to polychlorinated biphenyls (PCBs) and dioxins is associated with changes in the T-cell lymphocyte population in healthy Dutch infants. We investigated whether these changes persist into later childhood and whether background exposure to PCBs and dioxins is associated with the prevalence of infectious or allergic diseases and humoral immunity at preschool age. The total study group consisted of 207 healthy mother-infant pairs. We estimated prenatal exposure to PCBs and dioxins by the sum of PCBs 118, 138, 153, and 180 (sigmaPCB) in maternal and cord plasma and in breast-fed infants by the dioxin, planar, and mono-ortho PCB toxic equivalent (TEQ) levels in human milk. At 42 months of age, current body burden was estimated by the PCB in plasma. We assessed the prevalence of infectious and allergic diseases by parent questionnaire, and measured humoral immunity by antibody levels for mumps, measles, and rubella after primary vaccination. We performed immunologic marker analyses of lymphocytes in a subgroup of 85 children. Prenatal PCB exposure was associated with an increased number of lymphocytes, T-cells, and CD3CD8(+) (cytotoxic), CD4(+)CD45RO(+) (memory), T-cell receptor (TcR) [alpha]ss(+), and CD3(+)HLA-DR(+) (activated) T cells and lower antibody levels to mumps and measles at preschool age. Adjusted for confounders, prenatal PCB exposure was associated with less shortness of breath with wheeze, and current PCB body burden was associated with a higher prevalence of recurrent middle-ear infections and of chicken pox and a lower prevalence of allergic reactions. A higher dioxin TEQ was associated with a higher prevalence of coughing, chest congestion, and phlegm. We conclude that in Dutch preschool children the effects of perinatal background exposure to PCBs and dioxins persist into childhood and might be associated with a greater susceptibility to infectious diseases. Common infections acquired early in life may prevent the development of allergy, so PCB exposure might be associated with a lower prevalence of allergic diseases.     

Water arsenic exposure and intellectual function in 6-year-old children in Araihazar, Bangladesh

BACKGROUND: We recently reported results of a cross-sectional investigation of intellectual function in 10-year-olds in Bangladesh, who had been exposed to arsenic from drinking water in their home wells. OBJECTIVES: We present results of a similar investigation of 301 randomly selected 6-year-olds whose parents participated in our ongoing prospective study of the health effects of As exposure in 12,000 residents of Araihazar, Bangladesh. METHODS: Water As and manganese concentrations of tube wells at each home were obtained by surveying all study region wells. Children and mothers were first visited at home, where the quality of home stimulation was measured, and then seen in our field clinic, where children received a medical examination wherein weight, height, and head circumference were assessed. We assessed children's intellectual function using subtests drawn from the Wechsler Preschool and Primary Scale of Intelligence, version III, by summing weighted items across domains to create Verbal, Performance, Processing Speed, and Full-Scale raw scores. Children provided urine specimens for measuring urinary As and were asked to provide blood samples for blood lead measurements. RESULTS: Exposure to As from drinking water was associated with reduced intellectual function before and after adjusting for water Mn, for blood lead levels, and for sociodemographic features known to contribute to intellectual function. With covariate adjustment, water As remained significantly negatively associated with both Performance and Processing Speed raw scores; associations were less strong than in our previously studied 10-year-olds. CONCLUSION: This second cross-sectional study of As exposure expands our concerns about As neurotoxicity to a younger age group.     

Internal lead and cadmium exposure in 6-year-old children from western and eastern Germany

Lead and cadmium levels in blood and deciduous teeth (shed incisors only) of 6-year-old German children were determined in 1991 in a large epidemiological study carried out in rural and urban areas of western Germany (Duisburg, Essen, Gelsenkirchen, Dortmund, Borken) and eastern Germany (Leipzig, Halle, Magdeburg, Osterburg, Gardelegen, Salzwedel). In total, blood lead and cadmium levels of 2311 German children and tooth lead and cadmium levels of 790 German children were analyzed. Blood lead levels were generally low in all study areas with geometric means between 39.3 g/1 and 50.8 g/l in the western German and between 42.3 g/1 and 68.1 g/l in the eastern German study areas. The mean blood lead level of Turkish children (n = 213) living in the western German study areas was 50.1 g/l and thus 5.6 g/1 higher than the overall geometric mean of the western German children. The higher exposure may be explained by a higher oral uptake from food and different living conditions. These children were excluded from multiple regression analysis because they were all living in the western study areas. The mean tooth lead levels ranged between 1.50 and 1.74 g/g in the western and between 1.51 g/g and 2.72 g/g in the eastern study areas. Thus, they show a distribution pattern similar to blood. Blood and tooth lead levels were higher in urban than in rural areas and higher in the eastern German than in the western German study areas. With regard to the blood and tooth cadmium concentrations, no significant differences between the study areas could be found. The mean cadmium levels in blood ranged between 0.12 g/1 and 0.14 g/l and the mean tooth cadmium concentrations between 20.8 ng/g and 27.8 ng/g. Blood and tooth lead and cadmium levels of the eastern and western German children were thus mainly at a relatively low level in all rural and urban study areas. The study demonstrates and confirms that blood and tooth lead levels are influenced by several demographic, social, and environmental variables. The results indicate that there has been a further significant decrease of lead and cadmium exposure in western German children since our last epidemiological study carried out in the same study areas in 1985/1986.     

Sun exposure and number of nevi in 5- to 6-year-old European children

The occurrence and number of melanocytic nevi are among the most important known risk factors for the development of malignant melanoma. Studying the causes of nevi should lead to successful strategies in the prevention of melanoma. Among 11,478 white German children of preschool age the association between benign melanocytic nevi and a number of risk factors for skin cancer was examined. We found that subjects with a reported history of increased sun exposure, for example, painful sunburns, and an increased number of holidays in foreign countries with a sunny climate had significantly higher nevus counts than individuals without these characteristics. Our results provide further evidence that nevus counts may not only be part of a genetic predisposition but also a result of increased exposure to ultraviolet radiation. Together with the fact that a high nevus count is the most relevant risk factor for malignant melanoma, the results strongly indicate a connection between UV-radiation and the development of melanocytic skin cancer. In conclusion, strategies to reduce the incidence of melanoma should begin with young children.     

Lead exposure and intelligence in 7-year-old children: the Yugoslavia Prospective Study.

For a prospective study of lead exposure and early development, we recruited pregnant women from a lead smelter town and from an unexposed town in Yugoslavia and followed their children through 7 years of age. In this paper we consider associations between lifetime lead exposure, estimated by the area under the blood lead (BPb) versus time curve (AUC7), and intelligence, with particular concern for identifying lead's behavioral signature. The Wechsler Intelligence Scales for Children-Version III (WISC-III) was administered to 309 7-year-old children, 261 of whom had complete data on intelligence, blood lead, and relevant sociodemographic covariates (i.e., Home Observation for the Measurement of the Environment (HOME), birth weight, gender, sibship size, and maternal age, ethnicity, intelligence, and education). These showed anticipated associations with 7-year intelligence, explaining 41-4% of the variance in Full Scale, Performance, and Verbal IQ. Before covariate adjustment, AUC7 was unrelated to intelligence; after adjustment, AUC7 explained a significant 2.8%-4.2% of the variance in IQ. After adjustment, a change in lifetime BPb from 10 to 30 micro/dl related to an estimated decrease of 4.3 Full Scale IQ points; estimated decreases for Verbal and Performance IQ were 3.4 and 4.5 points, respectively. AUC7 was significantly and negatively related to three WISC-III factor scores: Freedom from Distractibility, Perceptual Organization, and Verbal Comprehension; the association with Perceptual Organization was the strongest. Consistent with previous studies, the IQ/lead association is small relative to more powerful social factors. Findings offer support for lead's behavioral signature; perceptual-motor skills are significantly more sensitive to lead exposure than are the language-related aspects of intelligence.     

Urinary porphyrin excretion in children is associated with exposure to organochlorine compounds

Background

Hexachlorobenzene (HCB) and other organochlorines induce porphyria cutanea tarda (PCT) in animal studies. Evidence in humans, however, is contradictory. In neonates and adults from a population historically highly exposed to HCB (Flix, Catalonia, Spain), no relation with PCT or with porphyrin excretion was found.

Objectives

We aimed to analyze the association between urinary porphyrin excretion and exposure to HCB and other organochlorinated compounds in children 4 years of age.

Methods

Our birth cohort included all newborns from Flix and the five surrounding towns (where no airborne pollution occurred). Among the 68 children with porphyrins we measured in cord blood, 52 children 4 years of age provided blood to measure organochlorine compounds, hair for methylmercury, and urine for porphyrin excretion pattern.

Results

Quantitative porphyrin excretion was within the normal values. However, total porphyrins, coproporphyrin I (CPI), and coproporphyrin III (CPIII) adjusted to creatinine excretion increased with increasing levels of HCB, 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (p,p′-DDE), 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (p,p′-DDT), and polychlorinated biphenyl congener 153 (PCB-153). We found no association with methylmercury. When we fitted multiple pollutant models, p,p′-DDE had the strongest association. We found these associations in children from both Flix and other towns, and they were independent of breast-feeding and of organochlorine and porphyrin levels at birth.

Conclusion

HCB at current levels did not induce porphyria or increase uroporphyrins. However, the increase of urinary coproporphyrins suggests an incipient toxic effect of the organochlorines, especially for p,p′-DDE, on the hepatic heme-synthesis pathway that differs from the major effects seen in PCT.     

4~8岁孤独症谱系障碍儿童与正常儿童后效区辨能力的比较

目的 比较孤独症谱系障碍(ASD)儿童与正常儿童后效区辨能力的差异,为ASD儿童的干预提供建议。方法 纳入2020年7月—2021年10月于上海市儿童医院儿童保健科确诊的ASD儿童22名,同期纳入年龄及智商匹配的正常儿童24名。通过对两组儿童进行后效区辨能力测试,比较两者之间后效区辨能力的差异。结果 ASD儿童动机操作下的正向、负向后效区辨能力分数与正常儿童相比差异无统计学意义(Z＝1.35、1.63, P>0.05)。ASD儿童外加视化标志的正向、负向后效区辨能力分数均低于正常儿童,差异具有统计学意义(Z＝2.83、5.04, P＜0.05),且ASD儿童外加视化标志的负向后效区辨能力分数低于正向后效区辨能力分数,差异具有统计学意义(Z=3.17, P＜0.05)。结论 ASD儿童外加视化标志的后效区辨能力低于正常儿童,且ASD儿童外加视化标志的负向后效区辨能力低于外加视化标志的正向后效区辨能力,建议在ASD儿童的康复训练中增加外加视化标志的后效区辨能力相关训练。     

平顶山市8岁学龄儿童患龋状况及影响因素分析

目的 了解平顶山市8岁学龄儿童龋病流行状况,探讨影响龋病发生发展的危险因素。 方法 参考“第三次全国口腔健康调查”的标准,采用分层整群抽样的方法,对1 762名适龄儿童进行口腔检查和问卷调查。 结果 平顶山市8岁学龄儿童患龋率84.68%,龋均4.79,城乡结合区域及农村儿童患龋率和龋均明显高于城市,差异有统计学意义(P＜0.05);乳、恒牙患龋率分别为83.65%、25.77%;城乡类型(OR=22.42)、家庭收入(OR=10.21)、睡前是否有吃零食习惯(OR=8.01)、吃完零食是否刷牙(OR=6.00)、进食甜食频率(OR=8.28)、刷牙方法(OR=8.88)、家长是否检查刷牙效果(OR=9.15)是影响患龋率的因素。 结论 平顶山市农村及城乡结合区域儿童患龋率较高,应加强口腔健康教育和龋病预防控制工作。     

Prenatal lead exposure and weight of 0- to 5-year-old children in Mexico city

Background: Cumulative prenatal lead exposure, as measured by maternal bone lead burden, has been associated with smaller weight of offspring at birth and 1 month of age, but no study has examined whether this effect persists into early childhood.Objective: We investigated the association of perinatal maternal bone lead, a biomarker of cumulative prenatal lead exposure, with children’s attained weight over time from birth to 5 years of age.Methods: Children were weighed at birth and at several intervals up until 60 months. Maternal tibia and patella lead were measured at 1 month postpartum using in vivo K-shell X-ray fluorescence. We used varying coefficient models with random effects to assess the association of maternal bone lead with weight trajectories of 522 boys and 477 girls born between 1994 and 2005 in Mexico City.Results: After controlling for breast-feeding duration, maternal anthropometry, and sociodemographic characteristics, a 1-SD increase in maternal patella lead (micrograms per gram) was associated with a 130.9-g decrease in weight [95% confidence interval (CI), –227.4 to –34.4 g] among females and a 13.0-g nonsignificant increase in weight among males (95% CI, –73.7 to 99.9 g) at 5 years of age. These associations were similar after controlling for concurrent blood lead levels between birth and 5 years.Conclusions: Maternal bone lead was associated with lower weight over time among female but not male children up to 5 years of age. Given that the association was evident for patellar but not tibial lead levels, and was limited to females, results need to be confirmed in other studies.