Geo-spatial and log-linear analysis of pedestrian and bicyclist crashes involving school-aged children

PROBLEM: There is a growing concern with the safety of school-aged children. This study identifies the locations of pedestrian/bicyclist crashes involving school-aged children and examines the conditions when these crashes are more likely to occur. METHOD: The 5-year records of crashes in Orange County, Florida where school-aged children were involved were used. The spatial distribution of these crashes was investigated using the Geographic Information Systems (GIS) and the likelihoods of crash occurrence under different conditions were estimated using log-linear models. RESULTS: A majority of school-aged children crashes occurred in the areas near schools. Although elementary school children were generally very involved, middle and high school children were more involved in crashes, particularly on high-speed multi-lane roadways. Driver's age, gender, and alcohol use, pedestrian's/bicyclist's age, number of lanes, median type, speed limits, and speed ratio were also found to be correlated with the frequency of crashes. DISCUSSION: The result confirms that school-aged children are exposed to high crash risk near schools. High crash involvement of middle and high school children reflects that middle and high schools tend to be located near multi-lane high-speed roads. IMPACT ON INDUSTRY: The pedestrian's/bicyclist's demographic factors and geometric characteristics of the roads adjacent to schools associated with school children's crash involvement are of interest to school districts.     

Low blood lead levels and hemoglobin concentrations in preschool children in China

It is well known that lead (Pb) produces reduced haemoglobin (Hb) levels and risk of anemia when blood lead levels (BPb) are greater than 20?µg?dL^?1. Two recent studies reported an increased risk of anemia in children with BPb between 10–20?µg?dL^?1, but few studies examined the association between Hb levels or risk of anemia and BPb under 10?µg?dL^?1. In the present study this association was examined using data of 140 preschool children from a larger prospective cohort study in China. Data showed that compared to children with BPb <5?µg?dL^?1, children with BPb between 7.5–10?µg?dL^?1 had significantly lower Hb levels, but there were no marked differences for other groups. A linear regression model showed a negative relationship between BPb and Hb levels after controlling for age, gender, height, weight, and iron (Fe) deficiency. This finding, although limited by a small sample size, suggests it may be important to examine Pb-induced hemosynthesis effect at concentrations less than 10?µg?dL^?1.     

Blood lead levels and nutrition in an urban community in Venezuela

Previous lead (Pb) exposure studies identified the Michelena sector in Valencia as a ‘critical’ area for Pb contamination. An analytical-ecological study was designed to evaluate the association of environmental and nutritional variables with blood lead (BPb) in children attending two schools located in this sector. A questionnaire was administered and the findings were correlated with BPb and serum-calcium (S-Ca) levels. The total population examined included 60 children (4–9 years old). The mean BPb values was 10.5?±?3?ug/dL (61.7%?≥?10?ug/dL) and the mean S-Ca was 8.9?±?0.7?mg/dL. A significant difference (p?=?0.042) was found between BPbs in males (11.1?±?3.1?ug/dL) when compared with females (9.6?±?2.8?ug/dL). Child age, school, schedule at school, parents' occupational exposure, habits, and socioeconomic status had no significant association with BPbs. The relationship between BPb levels (dependent variable) and the S-Ca and daily Ca intake levels (independent variables) was analysed through multiple regression analysis. The results show an inverse relationship between BPb and both variables (β?=??0.073, and β?=??0.001) respectively, with the daily Ca intake being the only significant variable in the model (p?=?0.04). Although average BPbs was not very high, the percentage of children with BPbs higher than the US-CDC intervention level was greater than those found in other studies. Since detailed information is generally unavailable for these children in Venezuela, this study provides insights for future research.     

Urinary arsenic methylation profile in children exposed to low arsenic levels through drinking water

There is a lack of information on arsenic metabolism in children exposed chronically to low levels of arsenic (<50 µg L^?1). The objective of this study was to determine the methylation profile of urinary arsenic metabolites in children exposed to low-level concentrations of arsenic via their drinking water. A cross-sectional study was undertaken in 50 children from four towns in the Yaqui Valley, Sonora, with total arsenic values of 39.9, 16.8, 7.3, and 5.5 µg L^?1 in their drinking water, respectively. First morning void samples were analyzed for inorganic-As (InAs), mono and dimethyl arsenic (MMA and DMA). The total arsenic excreted in urine ranged from 23.1 to 99.1 µg L^?1 and these levels did not vary by sex. Children with the highest level of total arsenic in their drinking water excreted the highest amount in urine and the length of residence and age also had significant contribution. Children with a lower range of arsenic exposure (16.8–5.5 µg L^?1) had similar amounts of arsenic in urine with values of 23.1, 28.2, and 32.6 µg L^?1, respectively. DMA had the highest proportion in urine (52.1–74.7%), followed by InAs (16.3–34.9%) and MMA (4.4–8.4%). Compared to other reports, these children excreted a low %MMA (6.1%), and children from the towns with the lowest levels of arsenic had the highest %InAs and the lowest %DMA. This variability in arsenic methylation was partially explained by arsenic concentration in drinking water, years of residence and age, and may reflect genetic differences or more contribution from different exposure routes. In conclusion, our results show that at low levels of exposure the children's ability to metabolize InAs did not have a linear association with the levels of arsenic, and overall children from the Yaqui Valley excrete a lower %MMA than expected.     

Trends over 1999–2014 in the concentrations of Ba,Cs, Co,Mo, Pb,Sb, Tl,and W in urine of US children aged 6–11 years

Data from National Health and Nutrition Examination Survey for children aged 6–11 years for 1999–2014 were used to study time trends and factors affecting the urinary levels of barium, cobalt, cesium, molybdenum, lead, antimony, thallium, and tungsten. Adjusted levels in urine declined every two years by 5.9% for barium, by 1.2% for cesium, by 18.2% for lead, and by 14% for antimony. For every additional smoker smoking inside a home, the levels of barium increased by 10.6% and for lead by 10%, but for tungsten levels decreased by 7.7%.     

广州市学龄儿童在校期间PM2.5暴露水平评价

采用便携式大气颗粒物采样器(MiniVol)和便携式颗粒物检测仪(pDR-1500)在2010年3月底至4月初对广州市某小学的室内外细颗粒物(PM2.5)浓度进行了监测,并对学龄儿童在校期间活动模式进行了跟踪调查,评价了学龄儿童在校期间PM2.5暴露水平.结果显示该小学室内外日均PM2.5浓度范围为25.1~145.9μg/m3,室内PM2.5浓度略低于室外,两者呈明显的正相关关系(R2=0.65);室内实时PM2.5浓度结果表明非假期与假期存在差异.使用离子色谱分析了PM2.5的阴离子成分,其中NO3-和SO42-占阴离子成分总量的73%~95%.研究显示道路交通源是采样地点PM2.5主要来源之一.学龄儿童在校期间单位体重PM2.5日均潜在暴露水平为7.6μg/(kg×d),个体日均潜在暴露水平为246.8μg/d.     

Carcinogenic effect of potential toxic metals in school children through contaminated drinking water around the industrial area of Pakistan

Due to papulation increase in Pakistan the demand of drinking water increased day by day. After the industrial grooming the wastewater producing harmful effect on the surrounding area of industries and drinking water contamination increased. Pakistan is on 82 amongst the 125 countries of the word having drinking water problem. Different parameter set by World Health Organization (WHO) and Pakistan Environmental Protection Agency (Pak-EPA) of hazard dimension index (HD) and Lifetime Cancerogenic risk Calculation (LFCR) of Potentially toxic metals that are As, Cd, Cr, Ni, Pb (PTMs) are higher, and the school age children are under high risk of cancer. All the drinking constraints set by regulating authority is fully neglected by inopportune human process by solid waste dumping and houses and industrial disposal with any proper treatment. This study discusses all the HD and LFCR parameter in three age group children, male and female through drinking water around the Hattar Industrial Estate (HIE) in Pakistan. In children and women more HD and LFCR thread than the adult man. The overall result shows that the HD risk is higher than the LFCR due to the PTMs in drinking water only HD is exceed from the limit of WHO and Pak-EPA. If there is no proper arrangement take place for the removal of As and PTMs from the industrial wastewater and drinking water than within few years all the population around the study area effected with different type of cancer.     

Emotional,physical, and social needs among 0–5‐year‐old children displaced by the 2010 Chilean earthquake: associated characteristics and exposures

An 8.8‐magnitude earthquake occurred off the coast of Chile on 27 February 2010, displacing nearly 2,000 children aged less than five years to emergency housing camps. Nine months later, this study assessed the needs of 140 displaced 0–5‐year‐old children in six domains: caregiver stability and protection; health; housing; nutrition; psychosocial situation; and stimulation. Multivariate regression was applied to examine the degree to which emotional, physical, and social needs were associated with baseline characteristics and exposure to the earthquake, to stressful events, and to ongoing risks in the proximal post‐earthquake context. In each domain, 20 per cent or fewer children had unmet needs. Of all children in the sample, 20 per cent had unmet needs in multiple domains. Children's emotional, physical, and social needs were associated with ongoing exposures amenable to intervention, more than with baseline characteristics or epicentre proximity. Relief efforts should address multiple interrelated domains of child well‐being and ongoing risks in post‐disaster settings.     

儿童消费市场特点及营销对策

儿童消费市场生机勃勃,蕴含着巨大的商机。儿童在现代家庭的消费结构中有着举足轻重的地位。本文针对儿童消费群体的特点,提出了相应的营销策略。使企业能够更好的做好符合儿童消费市场特点的营销工作,从而取得良好的经济效益和社会效益。     

中国农村儿童血铅水平分析研究

通过检索相关文献,收集国内1998～2006年公开发表的关于农村儿童血铅研究的论文,从中选择相关的文献进行综合分析。被纳入研究的49篇文献分析结果表明,我国农村儿童血铅水平在43.48～532.0μg/L,平均为105.17μg/L,中毒率范围为2.2%～88.1%,平均中毒率为26.8%。在所报道的21个省、市中,有8个省、市儿童血铅平均水平超过100μg/L。血铅平均值及铅中毒率最高的是安徽、云南、山西,最低的是湖南、重庆、吉林。受环境等因素的影响,我国农村儿童血铅水平较高,血铅的防治工作刻不容缓。