Toxicity of perfluorooctane sulfonic acid and perfluorooctanoic acid to Chironomus tentans

Two perfluorinated surfactants, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), were evaluated for their toxicity to the aquatic midge, Chironomus tentans. Impetus for this laboratory study originated from a 10-d, in situ field assessment in which C. tentans was exposed to PFOS at concentrations ranging from 300 to 30,000 microg/L. No midges survived these exposures. Midge survival in a preliminary, acute 10-d laboratory test with nominal PFOS concentrations ranging from 0.1 to 100,000 microg/L showed similar toxicity with respect to survival (median lethal concentration [LC50], 45.2 microg/L) and growth (median effective concentration [EC50], 27.4 microg/L). A parallel test using PFOA indicated no significant impacts on survival or growth. A definitive 10-d assay with PFOS concentrations ranging from 1 to 150 microg/L produced an EC50 for growth (87.2+/-11.6 microg/L) of the same order of magnitude as that in the preliminary findings. The same was not true for survival, however, with the LC50 falling outside the range of test concentrations. To further investigate the sensitivity of C. tentans to PFOS, we conducted a chronic life-cycle test using a nominal concentration range of 1 to 100 microg/L. Three of the four endpoints measured-survival, growth, and emergence-were significantly affected, with EC50 values of 92.2+/-3.1, 93.8+/-2.6, and 94.5+/-3.2 microg/L, respectively. Reproduction was not affected by those PFOS concentrations at which females emerged. The results of the present study indicate that PFOS toxicity thresholds for C. tentans are as much as three orders of magnitude lower than those reported for other aquatic organisms but, at present, are approximately two orders of magnitude higher than those concentrations typically observed in aquatic environments.     

Implications of attachment theory and research for developmental-behavioral pediatrics

This article presents a basic overview of attachment theory, concepts, and research. The review includes a discussion of the nature of the attachment relationship, its origins in human evolutionary history, and common misconceptions about attachment. We describe phases in the development of attachment relationships and review research on factors that influence attachment variations. We discuss the implications of variations in early attachment relationships for later development (adaptation and maladaptation). And finally, we review briefly the implications of attachment theory and research for pediatric practice. Some key points are that (1) virtually all infants become attached to caregivers regardless of quality of care; (2) attachment relationships evolve in phases over time; (3) children with disabilities form attachment relationships in ways comparable to nondisabled children but manifest attachment somewhat differently; (4) the consequences for attachment of out-of-home care, separations, and significant disruptions (e.g., adoption) depend on timing and circumstances; (5) many infant regulatory difficulties, as well as child behavior problems, originate in the caregiving relationship; and finally, (6) change in parent-child relationship disturbances is complex and requires time and effort.     

Daily methylphenidate use slows the growth of children: a community based study

OBJECTIVE: The use of methylphenidate (Ritalin) for treatment of attention deficit/hyperactivity disorder (ADHD) has increased dramatically over the last decade. However, the influence of methylphenidate on growth remains controversial. Our goals were to assess whether methylphenidate, as prescribed in the community setting, influences growth. DESIGN: We examined the growth of 84 patients with ADHD treated with methylphenidate in two large pediatric practices. Height standard deviation (SD) scores of treated children were compared with those of untreated biological siblings. We also analyzed the doses of methylphenidate in relation to changes in growth. RESULTS: We found significant differences in mean height SD scores between treated children and sibling controls after 2 years of treatment. Effects on growth were observed over the broad range of doses used (10-80 mg per day). CONCLUSIONS: Our findings suggest that the prevalence of grow-suppressive effects of methylphenidate is greater than previously suspected.     

Behavioral and emotional disturbances in the offspring of depressed parents with anger attacks

BACKGROUND: To examine the emotional and behavioral characteristics of the offspring of depressed parents with and without anger attacks. METHODS: Forty-three parents who met criteria for major depressive disorder (MDD) completed the Achenbach Child Behavior Checklist - Parent Report Version (CBCL) for each of their birth children (n = 58, age range 6-17 years). Unpaired t tests were used to evaluate the CBCL scale score differences between children of parents with and children of parents without anger attacks. Baseline demographics and clinical differences between the two groups of parents were also evaluated. RESULTS: Parents with anger attacks had a significantly younger age of onset of MDD. Offspring of depressed parents with anger attacks were found to have significantly lower social and school competency scale scores and higher scores for delinquency, attention problems, and aggressive behavior. In addition, this group was found to have a significantly higher total T score (a global measure of psychopathology). CONCLUSIONS: There are some important differences between offspring of depressed parents with and without anger attacks. This finding may be important in identifying and formulating intervention strategies for childhood problems in the offspring of depressed parents.     

Neonatal hearing loss in the indigent

OBJECTIVE: To compare the risk factor profile for neonatal hearing loss (HL), and the follow-up rate of those identified with HL in an indigent population with those in an insured population. STUDY DESIGN: Retrospective review. METHODS: We studied 4526 neonates from the high-risk nursery or neonatal intensive care unit from two adjacent hospitals in Houston, Texas. Ben Taub General Hospital (BTGH) is a county public hospital that serves mainly the indigent. Texas Children's Hospital (TCH) is a private tertiary care center that serves patients with private insurance and Medicaid. RESULTS: Overall, 133 infants failed the screening test. Follow-up diagnostic testing identified 48 patients with definite HL. Although nearly twice as many patients at BTGH failed screening compared with TCH (88 vs. 45), four times as many patients at BTGH did not return for diagnostic testing (43 vs. 10). When a hearing aid was needed, there was a delay in getting one at BTGH (P <.05). There was a higher prevalence of dysmorphic facial features and central nervous system disease and a lower prevalence of long-term ventilatory support at BTGH (P <.05). There were no differences between BTGH and TCH in the prevalence of low birth weight, neonatal asphyxia, syndromic stigmata, neonatal infection, family history of HL, or neonatal transfusion (P >.1). CONCLUSIONS: Significant differences in the risk factor profile for neonatal HL exist between the indigent and the general population. A worrisome problem exists with the timely intervention in hearing-impaired indigent neonates.