Survey of lead exposure around a closed lead smelter

OBJECTIVE: To test the hypothesis that elevated lead in soil is positively correlated with blood lead (BPb) levels in children in an urban population surrounding a closed lead smelter, a US Environmental Protection Agency Superfund clean-up site was surveyed. METHOD: A total of 827 volunteers including 490 children under 6 years of age participated. A questionnaire was administered. Blood lead was determined as was lead content of samples of house dust, soil, paint, and water of the participants' homes. RESULTS: The arithmetic mean venous BPb in 490 children between 6 and 72 months of age was 6.9 micrograms/dL (0.33 mumol/L) range 0.7 to 40.2 micrograms/dL (0.03 to 1.94 mumol/L). The BPb of 78 (16%) children in this group was > or = 10 micrograms/dL (0.48 mumol/L). Based on multiple regression modeling, lead in house dust accounted for 18% of the variance in BPb. Lead in paint together with the condition of the house were the main contributors to the dust lead variance (26%) with soil lead accounting for an additional 6%. Lead in paint alone accounted for 3% of the BPb variance. Lead in paint together with the condition of the house accounted for 12% of BPb variance, and lead in soil accounted for an additional 3%. Factors other than environmental lead such as education of parents, household income, and behavior were associated with BPb levels. CONCLUSIONS: The mean BPb in children was below the present level of concern of the Centers for Disease Control and Prevention. Children with BPb of > or = 10 micrograms/L (0.48 mumol/L) tended to live in poorly maintained older houses. Based on these findings lead in soil and paint in well-maintained homes contributed little to the lead exposure of children.     

CENP-G: a new centromeric protein that is associated with the alpha-1 satellite DNA subfamily

Lead is a highly toxic metal, the main source of which is contamination from combustion of unleaded petrol. The aims of this work were to detect the degree of lead exposure in a large sample of children; determine the relationship between blood lead levels (BPb) and age, sex, habitat and season of the year; and correlate BPb with zinc protoporphyrin (ZPP) values. A cross-sectional study was carried out. Blood from routine extractions drawn at our centre was used. BPb and ZPP were measured by atomic absorption spectrophotometry and haematofluorimetry, respectively. We analysed 1158 blood samples from children. BPb (mean +/- SEM): 0.22 +/- 0.04 mumol l-1. Correlation BPb-age: BPb = 0.19 + 0.086 x age (months), r = 0.129, P < 0.0001. BPb was greater in boys (0.23 +/- 0.007 versus 0.20 +/- 0.006 mumol l-1, P < 0.0002). No differences were observed between habitats (urban versus rural). BPb were higher in the warm months (0.24 +/- 0.013 versus 0.21 +/- 0.007 mumol l-1, P < 0.0001). Prevalence of lead intoxication (BPb > 0.48 mumol l-1) was 4.2%. No differences in prevalence were found among the different groups. The correlation between BPb and ZPP showed r = 0.0969, P = 0.0024. Utility for screening: sensitivity of 53.7% and specificity of 59.3% (cut-off point of 60 mumol ZPP mol-1 haem). We can conclude that lead exposure in children in our sample was in the range reported in similar studies in other areas and countries, and below the toxic limit. None of the factors analysed significantly influenced lead intoxication prevalence. There was no good correlation between ZPP and BPb in our samples and the ZPP cut-off point used did not present good specificity and sensitivity values.     

Exogenous adenosine potentiates hypnosis induced by intravenous anaesthetics

AIMS: To determine whether adverse drug reactions (ADRs) to herbal remedies would be reported differently from similar ADRs to conventional over-the-counter (OTC) medicines by herbal-remedy users. METHODS: Face-to-face interviews (using a structured questionnaire) with 515 users of herbal remedies were conducted in six pharmacy stores and six healthfood stores in the UK. The questionnaire focused on the likely course of action taken by herbal-remedy users after experiencing an ADR associated with a conventional OTC medicine and a herbal remedy. RESULTS: Following a 'serious' suspected ADR, 156 respondents (30.3%) would consult their GP irrespective of whether the ADR was associated with the use of a herbal remedy or a conventional OTC medicine, whereas 221 respondents (42.9%) would not consult their GP for a serious ADR associated with either type of preparation. One hundred and thirty-four respondents (26.0%) would consult their GP for a serious ADR to a conventional OTC medicine, but not for a similar ADR to a herbal remedy, whereas four respondents (0.8%) would consult their GP for a serious ADR to a herbal remedy, but not for a similar ADR to a conventional OTC medicine. Similar differences were found in attitudes towards reporting 'minor' suspected ADRs. CONCLUSIONS: Consumers of herbal remedies would act differently with regard to reporting an ADR (serious or minor) to their GP depending on whether it was associated with a herbal remedy or a conventional OTC medicine. This has implications for herbal pharmacovigilance, particularly given the increasing use of OTC herbal remedies. The finding that a high proportion of respondents would not consult their GP or pharmacist following ADRs to conventional OTC medicines is also of concern.     

The relationship of blood lead and dietary calcium to blood pressure in the normative aging study

BACKGROUND: Previous studies have demonstrated a positive relationship between elevated blood lead (BPb) and blood pressure (BP), but few have additionally examined the role of dietary calcium. METHODS: The cross-sectional relationship between BPb and BP and the possible protective influence of increased dietary calcium on that relationship was examined among 798 male participants in the Normative Aging Study (NAS), a cohort of older men with relatively low BPb levels. RESULTS: The age range of these subjects was 43-93 years (mean = 66.1, SD = 7.4 years) and blood lead concentrations ranged form 0.5 to 35 mcg/dl (median = 5.6 mcg/dl). For the cohort overall, neither ln blood lead nor dietary calcium were significantly correlated with BP. In multivariate linear regression analyses that adjusted for age, body mass index, dietary calcium intake (adjusted for total calorie intake), alcohol intake, sitting heart rate, kilocalories/week expended in exercise, haematocrit, and smoking status, a unit increase in ln BPb predicted an increase on 1.2 mmHg diastolic blood pressure (DBP) (95% CI : 0.11, 2.2; P = 0.03). Adjusted calcium intake of 800 mg/day predicted a decrease of 3.2 mmHg systolic blood pressure (SBP) (95% CI : -5.6, -0.24, P = 0.03). There was no evidence of an interaction between dietary calcium intake and blood lead on BP. When the analyses were restricted to those men <=74 years old, a unit increase in ln BPb predicted an increase of 1.6 mmHg DBP (n = 681; 95% CI : 0.42, 2.7; P = 0.007). However, when men on antihypertensive medication (AHM) were excluded from the analyses, ln BPb was not significantly associated with increased DBP nor was adjusted calcium significantly associated with SBP. CONCLUSIONS: The study did support the hypothesis that increased BPb was associated with increased DBP in a cohort of older men with low blood lead, but there was no evidence of interaction between BPb and dietary calcium on BP. However, the relationship between increased BPb and DBP did not hold when those on anti-hypertensive medications were excluded.     

Genetic basis of variation in carotid artery wall thickness

BACKGROUND AND PURPOSE: Other than the documented associations of risk factors and carotid artery wall thickness, the genetic basis of variation in carotid artery intimal-medial thickness (IMT) is unknown. The purpose of this study was to examine the extent to which variation in common carotid artery (CCA) IMT and internal carotid artery (ICA) IMT are under genetic control. METHODS: The sibship data used for this analysis were part of an epidemiological survey in Mexico City. The CCA and ICA analyses were based on 46 and 44 sibships of various sizes, respectively. The CCA and ICA IMTs were measured with carotid ultrasonography. Using a robust variance decomposition method, we performed genetic analyses of CCA IMT and ICA IMT measurements with models incorporating several cardiovascular risk factors (eg, lipids, diabetes, blood pressure, and smoking) as covariates. RESULTS: After accounting for the effects of covariates, we detected high heritabilities for CCA IMT (h2 = 0.92 +/- 0.05, P = .001) and ICA IMT (h2 = 0.86 +/- 0.13, P = .029). Genes accounted for 66.0% of the total variation in CCA IMT, whereas 27.7% of variation was attributable to covariates. For ICA IMT, genes explained a high proportion (74.9%) of total phenotypic variation. The covariates accounted for 11.5% of variation in ICA IMT. CONCLUSIONS: Our results suggest that substantial proportions of phenotypic variance in CCA IMT and ICA IMT are attributable to shared genetic factors.     

Effect of zinc supplementation on growth and body composition of Ugandan preschool children: a randomized, controlled, intervention trial

BACKGROUND: Despite ample food supplies, the incidence of childhood underweight and stunting remains high in Uganda. Many factors contribute to this situation, but the role of low zinc intakes has not been adequately explored. OBJECTIVE: Our objective was to study the effect of zinc supplementation on growth and body composition of preschool children by using the outcome measures of weight, height, and midupper arm circumference (MUAC). DESIGN: The study was randomized, double-blind, placebo-controlled, parallel, and 8 mo long, and incorporated 6 mo of zinc supplementation. Children (n = 153) aged 55.8 +/- 11.2 mo from 3 randomly selected nursery schools of medium, low, and very low socioeconomic status in a suburb of Kampala took part. The intervention comprised 10 mg Zn (as ZnSO4) or placebo daily in freshly prepared fruit juice, Monday to Friday inclusive. RESULTS: Zinc supplementation increased MUAC by the end of the study (P = 0.029) and led to greater weight gain in children from the school of medium socioeconomic status at 3 and 8 mo (P = 0.019 and P = 0.038, respectively). There was no effect on weight gain of the children from the other schools. Zinc supplementation had no influence on height. Infection rates (of which 82% were recorded as malaria) were lower in the zinc-supplemented group than in control subjects (P = 0.063). CONCLUSIONS: Zinc supplementation may counter the age-related decrease in MUAC often observed in preschool children in developing countries. The study provides evidence that zinc may not be the most limiting nutrient for weight gain in children of poor nutritional status, but may become so as nutritional status improves.     

Effects of hepatic stimulator substance, herbal medicine, selenium/vitamin E, and ciprofloxacin on cirrhosis in the rat

BACKGROUND & AIMS: Cirrhosis is a potentially lethal condition for which there is no proven effective therapy. The aim of this study was to compare the effects of hepatic stimulator substance, traditional Chinese herbal medicine, selenium plus vitamin E, and ciprofloxacin treatment on biochemical and histological features of fibrosis in rats with carbon tetrachloride (CCl4)/ethanol-induced cirrhosis. METHODS: One hundred twenty adult Wistar rats were divided into six study groups (20 rats/group): healthy controls, CCl4/ethanol-injured rats left untreated, and CCl4/ethanol-injured rats treated for 4 weeks with either hepatic stimulator substance, traditional Chinese herbal medicine, a combination of selenium plus vitamin E, or ciprofloxacin. After the 4-week treatment, rats were killed and the following parameters of hepatic fibrosis were determined: hepatic hydroxyproline and proline levels, serum hyaluronic acid concentrations, and histological staining of hepatic tissue. RESULTS: Hepatic fibrosis was significantly improved in all four treated groups compared with the untreated CCl4/ethanol-injured controls. Improvements were most striking in the groups treated with traditional Chinese herbal medicine and ciprofloxacin. CONCLUSIONS: The data indicate that hepatic stimulator substance, traditional Chinese herbal medicine, selenium plus vitamin E, and ciprofloxacin significantly decrease the amount of hepatic fibrosis caused by CCl4/ethanol injury in rats.     

Adjustment of Mothers of Children With Obstetrical Brachial Plexus Injuries: Testing a Risk and Resistance Model.

Objective: To investigate direct and moderating effects of risk and resistance factors on the adjustment of mothers of children with obstetrical brachial plexus injuries (OBPI). Participants: Fifty-three mothers of children with OBPI recruited from an OBPI clinic in an Australian pediatric hospital. Measures: OBPI Severity Scale, Parents of Children With Disabilities Inventory, Family APGAR, Short Form Social Support Questionnaire-6, Life Orientation Test-Revised, Perceived Control of Internal States Scale, General Health Questionnaire-12. Results: The factors explained 30% of maternal adjustment variation. Resistance factors explained a unique 18%. Optimism was the only significant moderator. Conclusions: Findings confirm the importance of risk and resistance factors in maternal adjustment and enhance understanding by identifying optimism as a moderator of the risk/adjustment relationship. Interventions promoting optimism may facilitate maternal adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cost-effectiveness analysis of lead poisoning screening strategies following the 1997 guidelines of the Centers for Disease Control and Prevention

OBJECTIVE: To compare blood lead (BPb) poisoning screening strategies in light of the 1997 recommendations by the Centers for Disease Control and Prevention, Atlanta, Ga. DESIGN: Cost-effectiveness analysis from the perspective of the health care system to compare the following 4 screening strategies: (1) universal screening of venous BPb levels; (2) universal screening of capillary BPb levels; (3) targeted screening of venous BPb levels for those at risk; and (4) targeted screening of capillary BPb levels for those at risk. Costs of follow-up testing and treatment were included in the model. RESULTS: Only universal venous screening detected all BPb levels of at least 0.48 micromol/L (10 microg/dL). Universal capillary screening detected between 93.2% and 95.5% of cases, depending on the prevalence of elevated BPb levels. Targeted screening was the least sensitive strategy for detecting cases. Venous testing identified between 77.3% and 77.9% of cases, and capillary testing detected between 72.7% and 72.8% of cases. In high-prevalence populations, universal venous screening minimized the cost per case ($490). In low- and medium-prevalence populations, targeted screening using venous testing minimized the cost per case ($729 and $556, respectively). In all populations, regardless of screening strategy, venous testing resulted in a lower cost per case than capillary testing. Sensitivity analyses of all parameters in this model demonstrated that this conclusion is robust. CONCLUSIONS: Universal screening detects all cases of lead poisoning and is the most cost-effective strategy in high-prevalence populations. In populations with lower prevalence, the cost per case detected using targeted screening is less than that of universal screening. The benefit of detecting a greater number of cases using universal screening must be weighed against the extra cost of screening. Regardless of whether a strategy of universal or targeted screening is used, the cost per case using venous testing is less than that of capillary testing.     

Evidence for an antemortem injury of a burned head dissected from a burned body

This paper describes risk factors for dental caries identified among 491 2-year-olds in the city of Ume?, Sweden. The study was performed as a risk screening for dental caries according to a method developed for use by dental assistants. The sugar consumption was high, 80% of the 2-year-olds had sweets once a week or more and 25% had sweet beverages once a day or more frequently. In addition, 14% of the children had a meal at night and most common were formula, bovine milk or breastmilk. The majority of the parents brushed the child's teeth at least daily using fluoride toothpaste. Among the children 6% had a chronic somatic disorder and 6% had an intolerance towards specific foods, milk being the most common. The high level of sugar consumption indicates that improved dental health education focusing on the importance of limiting sugar consumption is needed among parents with young children.     

Mental health service use among young children receiving pediatric primary care

OBJECTIVE: To investigate the factors associated with mental health service use among young children. METHOD: Five hundred ten preschool children aged 2 through 5 years were enrolled through 68 primary care physicians, with 388 (76% of the original sample) participating in a second wave of data collection, 12 to 40 months later. Consensus DSM-III-R diagnoses were assigned using best-estimate procedures. The test battery included the Child Behavior Checklist, a developmental evaluation, the Rochester Adaptive Behavior Inventory, and a videotaped play session (preschool children) or structured interviews (older children). At wave 2, mothers completed a survey of mental health services their child had received. RESULTS: In logistic regression models, older children, children with a wave 1 DSM-III-R diagnosis, children with more total behavior problems and family conflict, and children receiving a pediatric referral were more likely to receive mental health services. Among children with a DSM-III-R diagnosis, more mental health services were received by children who were older, white, more impaired, experiencing more family conflict, and referred by a pediatrician. CONCLUSIONS: Young children with more impairment and family conflict are more likely to enter into treatment. Services among young children of different races with diagnoses are not equally distributed. Pediatric referral is an important predictor of service use.     

Clinical presentation of chronic non-infectious rhinitis in children

Chronic rhinitis is one of the commonest conditions affecting humans and there is evidence that its prevalence (and especially that of allergic rhinitis) is increasing. Although common, it is poorly recognised by doctors, parents and patients, particularly in children. AIMS: This study surveyed children with chronic non-infectious rhinitis to describe their presenting symptoms, differences in presentation between preschool and school-aged children and the prevalence of complications. SUBJECTS AND METHODS: We prospectively surveyed patients with a diagnosis of chronic rhinitis that was subsequently confirmed by response to therapy. Symptoms of rhinitis were assessed via an interview-conducted questionnaire. RESULTS: 567 children (357 boys), with a mean age (+/-SD) of 5.3 +/- 3.6 years, were studied over 14 months. Three hundred and fourteen were preschool children. Symptoms of a blocked or a runny nose were reported in 85% of patients, both symptoms occurring simultaneously in 59.9%. A blocked nose occurred more frequently in school-aged children, while a runny nose was commoner in preschool children. Sneeze and itch occurred less frequently in 56.1% and 33.6%, respectively. Complicating recurrent ear infections were reported in 46.9% of patients, more frequently in preschool children (P = 0.01); almost one-third (32.02%) had had grommets inserted. Learning problems, possibly secondary to somnolence as a result of poor sleep induced by sleep apnoea (snoring was reported in 58.4%), were reported in 24.1% of school-going children. CONCLUSION: As chronic rhinitis in South Africa commonly manifests with a blocked nose, patients display a high prevalence of associated complications. Doctors need to be aware of the presenting symptoms to diagnose and treat chronic non-infectious rhinitis earlier to prevent these complications.     

Prospective relations between growth in drinking and familial stressors across adolescence.

Although there is much empirical support for the relation between stress and alcohol consumption in adolescence, it is unclear whether exposure to stressors is associated with overall trajectories or temporary elevations in drinking. Moreover, little research has explored whether the stress–alcohol use association in adolescence may be explained by shared risk factors that produce both individual differences in stress exposure and elevated risk for alcohol use. The present study tested these hypotheses within the context of a state-trait model of family stressors in a prospectively studied sample of children at high risk for alcoholism: children of alcoholic parents and matched controls (n = 451). Levels and growth in alcohol use were modeled longitudinally from ages 13 to 17. Results indicated that shared risk factors accounted for 53% of the impact of trait family stressors on growth in adolescent drinking, but time-specific exposure to familial stressors still predicted short-term boosts in alcohol use in adolescence. These findings imply that trait familial stressors mark adolescents at risk for alcohol use and also impact adolescent alcohol use within a short time frame (i.e., over 1 year vs. over many years) when they occur above and beyond the adolescent’s “usual load” of stressors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Childhood cancer and parental use of tobacco: deaths from 1971 to 1976

Parental smoking data have been reabstracted from the interview records of the Oxford Survey of Childhood Cancers (deaths from 1971 to 1976). Reported smoking habits for the parents of 2587 children who died with cancer were compared with similar information for the parents of 2587 healthy controls (matched pairs analysis). Maternal daily consumption of cigarettes and paternal use of pipes or cigars were unimportant, but there was a statistically significant positive trend between paternal daily consumption of cigarettes and the risk of childhood cancer (P < 0.001). This association could not be explained by maternal smoking, social class, parental ages at the birth of the survey child, sibship position or obstetric radiography. Relations between maternal consumption of cigarettes and birth weights suggested that (maternal) smoking data were equally reliable for case and control subjects. About 14% of all childhood cancers in this series could be attributable to paternal smoking. These data were combined with smoking data from two previously published reports from the Oxford Survey (deaths from 1953 to 1955, deaths from 1977 to 1981) to obtain further information on risks for different types of cancer and different ages at onset of disease. Paternal cigarette smoking emerged as a potential risk factor both for the generality of childhood cancer and for all ages at onset.     

Children with in utero cocaine exposure do not differ from control subjects on intelligence testing

OBJECTIVE: To determine if in utero cocaine exposure affects IQ scores in children at age 4 years. DESIGN: A prospective, longitudinal evaluation by blinded examiners of the IQ scores of cocaine-exposed and control children of low socioeconomic status who have been observed since birth. SETTING: A study center in an inner-city hospital. PARTICIPANTS: One hundred one children with in utero cocaine exposure and 118 control children, all of whom were 34 weeks' gestational age or older and nonasphyxiated at birth. MAIN OUTCOME MEASURE: Intelligence quotient scores on a standardized intelligence test, the Wechsler preschool and Primary Scale of Intelligence--Revised. RESULTS: Seventy-one cocaine-exposed and 78 control children were administered the Wechsler Preschool and Primary Scale of Intelligence--Revised. Maternal, natal, and 30-month characteristics of the children tested did not differ from those not tested. Groups did not differ on mean Performance (83.2 vs 87.0), Verbal (79.0 vs 80.8), or Full Scale (79.0 vs 81.9) IQ scores (all P > or = .10 [values for cocaine-exposed children given first]). None of these 3 scores was associated with cocaine exposure in multivariate linear regressions. Although cocaine-exposed and control groups did not differ in outcome, 93% of cocaine-exposed and 96% of control children had Full Scale IQ scores below 100, the mean IQ score for the test. CONCLUSIONS: In an inner-city cohort, IQ scores did not differ between cocaine-exposed and control children. However, both groups performed poorly.     

Efficacy of lodoxamide 0.1% versus N-acetyl aspartyl glutamic acid 6% ophthalmic solutions in patients with vernal keratoconjunctivitis

The purpose of this study was to investigate environmental lead exposure in the general Taiwanese population. A total of 8828 Taiwanese adults selected by a multistage sampling method were investigated. Characteristics of the participants were ascertained by questionnaire and 10 ml venous blood was drawn by public health nurses. The blood specimens were distributed to six laboratories for blood lead level (BLL) measurement. A quality control program was applied during the analysis of the BLLs in order to improve precision and accuracy. The arithmetic mean BLL of the 8828 Taiwanese adults was 7.70 +/- 5.23 micrograms/dl, with a maximal level of 69.1 micrograms/dl. The median was 6.5 micrograms/dl and the 90th percentile was 14.0 micrograms/dl. After logarithmic transformation, the geometric mean was 1.84 +/- 0.67 microgram/dl. This study also found that elevated BLLs were associated with certain personal characteristics, i.e., gender, ethnic group, and education level; life-style factors, such as smoking, alcohol consumption, Chinese herbal drug consumption, milk consumption, and sources of drinking water; residential location, i.e., level of urbanization; and occupational history of lead exposure. However, age, floor level of residence, distance from house to road, and betel nut consumption were not associated with elevated BLLs. These results showed that BLLs in the Taiwanese population were not higher than those in developed and developing countries. Most of the influencing factors were also found in other studies; however, local factors such as ethnic group, Chinese herbal drug consumption, and sources of drinking water are important considerations in Taiwan when examining ways to prevent overexposure to lead in the general population.     

Developmental changes in foveal tachistoscopic recognition between prereading and reading children.

12 preschool and 16 3rd grade children matched the orientation (vertical or horizontal) of a bar which appeared randomly within 1 of 35 circles in a 5 * 7 array by touching 1 of 2 marked panels. Stimuli were tachistoscopically presented at times individually set to achieve about 75% correct performance. Preschool Ss showed no superiority on the left vs the right. The 3rd graders showed significant top and right superiorities. Results are compared with those for adults on the same task. Asymmetries in recognition still appear among children when reporting and rehearsal factors are controlled, but they cannot be easily explained in terms of the reading development hypothesis of sequential processing. (36 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Industrial accidents are related to relative body weight: the Israeli CORDIS study

OBJECTIVES: The accident rate might be influenced by intrinsic characteristics of the workers, by risks inherent in the work environment, or a combination of these factors. As increased weight may be associated with sleep disturbances and fatigue, a high body mass index (BMI) might be an independent risk factor for accidents in industrial workers. METHODS: 3801 men were examined and followed up for two years for the occurrence of accidents. The objective environmental conditions were recorded and translated into a single score of ergonomic stress levels. Height and weight were recorded, as were possible confounding factors including measures of fatigue, type A personality, total night time sleep, job satisfaction, somatic complaints, smoking, and education levels. RESULTS: Both BMI and ergonomic stress levels independently predicted involvement in accidents (two or more) with those in the highest BMI quartile who worked in an environment with high ergonomic stress levels having a 4-6 times increased risk of accidents compared with those in the lowest BMI quartile who worked in an environment with low ergonomic stress levels (95% confidence interval (95% CI) 2.4-9.0, P < 0.001). Although increasing somatic complaints and a low educational level also were predictors of accidents, they did not mediate the effect of the BMI on the accident rate. Increasing age, less smoking, and decreased sleep hours were significantly associated with an increased BMI, but the association of BMI and involvement in accidents also could not be explained by those factors or the other confounders. CONCLUSIONS: BMI independently influences the accident rate. Further studies warranted to confirm these findings and to explore mechanisms supporting biological plausibility.     

Lipofuscin product accumulation, insufficient antioxidant defence in erythrocytes and plasma and enhanced susceptibility to oxidative haemolysis after thermal trauma

The paper presents the results of the large-scale blood lead levels survey in pre-school urban children living in industrial area of Poland (Katowice Voivodship, Upper Silesian Industrial Zone-USIZ). The program, established in 1993, involves education, screening and medical care of case-children, as its major elements. Until December 1995 six thousand nine hundred sixty nine children aged 2-6 years have been examined in three towns (Chorzów, Kalowice, Sosnowiec). Geometric mean value of blood lead level (PbB) was slightly but not statistically significantly larger in boys (6.68 +/- 1.51 micrograms/dl) than in girls (6.58 +/- 1.54 micrograms/dl). In a multiple regression analysis the following variables explained variation in PbB: town (p = 0.0001), age (p = 0.005), floor on which apartment was located (p = 0.0001), number of siblings (p = 0.0001), apartment quality (p = 0.0001), carpet in a child's room (p = 0.0001), consumption of locally grown vegetables (p = 0.007), frequent trips outside the region (p = 0.0001). The results were verified with PbB as dichotomous variable. The occurrence of PbB above 10 micrograms/dl (frequency, 14.2%-17.2%) was associated with floor on which apartment was located, number of siblings, apartment's quality, the presence of carpet in child's room and frequent trips outside the region. The occurrence of PbB above 15 micrograms/dl (frequency: 2.5%-4.2% of children) was associated with the same variables and additionally, with the place of residence and intensity of vehicle traffic. The findings yield reliable population-based estimates of the risk of over-exposure of "non-hot-spot" urban children to environmental lead and highlight the important role of factors that could be classified as environmental and socio-economical determinants of blood lead level. Among environmental factors deposits of lead are still a problem in a densely populated industrial center of USIZ and the use of leaded gasoline adds to the magnitude of exposure.