Water treatment with silicofluorides and lead toxicity

Toxic metals like lead, manganese, copper and cadmium damage neurons and deregulate neurotransmitters like serotonin and dopamine (which are essential to normal impulse control and learning). Earlier studies show that — controlling for socio‐economic and demographic factors — environmental pollution with lead is a highly significant risk factor in predicting higher rates of crime, attention deficit disorder or hyperactivity, and learning disabilities. Exposure and uptake of lead has been associated with industrial pollution, leaded paint and plumbing systems in old housing, lead residues in soil, dietary habits (such as shortages of calcium and iron), and demographic factors (such as poverty, stress, and minority ethnicity). We report here on an additional “risk co‐factor” making lead and other toxic metals in the environment more dangerous to local residents: the use of silicofluorides as agents in water treatment. The two chemicals in question — fluosilicic acid and sodium silicofluoride — are toxins that, despite claims to the contrary, do not dissociate completely and change water chemistry when used under normal water treatment practices. As a result, water treatment with siliconfluorides apparently functions to increase the cellular uptake of lead. Data from lead screening of over 280,000 children in Massachusetts indicates that silicofluoride usage is associated with significant increases in average lead in children's blood as well as percentage of children with blood lead in excess of 10μg/dL. Consistent with the hypothesized role of silicofluorides as enhancing uptake of lead whatever the source of exposure, children are especially at risk for higher blood lead in those communities with more old housing or lead in excess of 15 ppb in first draw water samples where silicofluorides are also in use. Preliminary findings from county‐level data in Georgia confirm that silicofluoride usage is associated with higher levels of lead in children's blood. In both Massachusetts and Georgia, moreover, behaviors associated with lead nurotoxicity are more frequent in communities using silicofluorides than in comparable localities that do not use these chemicals. Because there has been insufficient animal or human testing of silicofluoride treated water, further study of the effect of silicofluorides is needed to clarify the extent to which these chemicals are risk co‐factors for lead uptake and the hazardous effects it produces.     

Psychoneuroendocrinology of anxiety disorders

This article focuses on neuroendocrine measures in anxiety disorders and their relationships to neurotransmitter and neuroendocrine function. In particular, the hypothalamic-pituitary-somatotropin and the hypothalamic-pituitary-adrenal (HPA) axes are emphasized, and a role for extrahypothalamic corticotropin releasing factor is proposed. Additional neuroactive hormones are also considered. A nonhuman primate model of anxiety is discussed in terms of its neuroendocrine relevance. And, throughout, a hypothetical functional-anatomic model for anxiety and panic is proposed using the findings of cognitive neuroscience fear research. Finally, an effort is made to synthesize existing psychoneuroendocrinologic data into a current conceptualization of the pathophysiology of anxiety disorders.     

Clinical utility of the selective serotonin reuptake inhibitors in the spectrum of anxiety

The selective serotonin reuptake inhibitors (SSRIs) are now being employed in the treatment of the full spectrum of anxiety disorders. In comparative trials, the SSRIs are proving to be equal or superior in efficacy to traditional antianxiety medications. Due to their favorable side effect profile, safety, and tolerability, they are rapidly replacing older agents in the treatment of anxiety. Neuroanatomical pathways that may be important in the antianxiety effect of the SSRIs are outline and discussed, followed by a review of the clinical evidence supporting the efficacy of this class of medications in the treatment of anxiety disorders.     

Patterns of Residential Mobility Amongst Children in Greater Johannesburg–Soweto, South Africa: Observations from the Birth to Twenty Cohort

Frequent residential movement challenges children to adapt to change, amongst others, houses and neighbourhoods, friends and schools, and this may have either or both negative and positive influences on their health and well-being. However, there is currently little knowledge of the patterns of child residential mobility within South Africa’s urban environment. This paper uses address data of children in the Birth to Twenty cohort to analyse the frequencies and patterns of residential mobility observed over the first 14 years of these children’s lives. Of the 3,273 children enrolled into the cohort in 1990, two thirds of the children (64%) have moved home at least once. Nonetheless, a third of the children never moved, indicating some stability among the urban child population. Residential moves by children were found to be associated with both the lowest resourced and the highest resourced households.     

Where do anxious children “fit” best? Childcare and the emergence of anxiety in early childhood.

The goal of this study was to explore the role of childcare history as a potential moderating factor in the development of anxiety in early elementary school. Data were drawn from multiple cycles of the National Longitudinal Survey of Children and Youth. At Time 1, the sample included n = 3,100 children aged 4 to 5 years. Based on parent ratings at Time 1, groups of extremely anxious, aggressive, and comorbid children were identified, as well as a comparison group. Parents also reported on children's primary care experiences (e.g., centre-based care, home-based care, no care). Two years later, teachers provided ratings of child anxiety and aggression in elementary school. Results indicated an interaction between early behavioural risk group and childcare type in the prediction of later anxiety. Anxious children who participated in home-based care were significantly less anxious 2 years later than anxious children in the centre-based care or no-care groups. Results are discussed in terms of the importance of the fit between child characteristics and childcare type in the emergence of anxiety in early childhood. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Come out and play: Shyness in childhood and the benefits of organized sports participation.

The purpose of the current study was to examine the role of organised sport participation as a moderator of the links between shyness and psychosocial maladjustment in childhood. Participants at Time 1 were 355 elementary schoolchildren (Mage=10.1 years, SD=0.6); at Time 2, 1 year later, 201 children (56%) were retained. At both time points, children completed self-report assessments of their shyness and aggression, sport participation, and psychosocial adjustment. Parents also rated children's social skills. Overall, results indicated that sport participation was positively related to indices of positive adjustment (e.g., social skills, self-esteem). In contrast, shyness was associated with social skill deficiencies and internalizing problems. However, some evidence was also found to suggest that sport participation plays a unique protective role for shy children. Shy children who participated in sport over time reported a significant decrease in anxiety. Results are discussed in terms of the role of sport as a social context to enhance shy children's peer relations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Do You "Want" to Play? Distinguishing Between Conflicted Shyness and Social Disinterest in Early Childhood.

This study attempted to distinguish two types of social withdrawal in early childhood: (a) one based on social fear and anxiety despite a desire to interact socially (conflicted shyness) and (b) one based on the lack of a strong motivation to engage in social interaction (social disinterest). Two samples of preschoolers (n = 119 and n = 127) 3-5 years of age participated. Their mothers completed the newly developed Child Social Preference Scale, which was designed to assess conflicted shyness and social disinterest. Maternal ratings of child temperament, parenting style, and social goals, teacher ratings of child social adjustment, observations of child free-play behaviors, and child interview assessments of perceived competence and preference for playing with peers were also collected. Distinct patterns of associations were found between conflicted shyness and social disinterest and outcome variables. Implications for the motivational underpinnings and adjustment outcomes of shyness and social disinterest are explored (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Detection of Lyman Alpha Radiation Formed by the Slowing Down of Protons and Tritons Produced by the 3He (n,tp) Reaction—A Model Study

The observation of Lyman alpha (Lα) radiation produced by the end products of the ³He (n,tp) reaction has suggested the possibility of a new method of cold thermal neutron detection. In order for this goal to be achieved, a basic understanding of how the Lα radiation is formed and how it may be detected, is needed. The model study described here is an attempt to provide this basic understanding and to provide quantitative results that can be used in designing future experiments.