The hierarchy of environmental health and safety practices in the U.S. nanotechnology workplace.

Manufacturing of nanoscale materials (nanomaterials) is a major outcome of nanotechnology. However, the potential adverse human health effects of manufactured nanomaterial exposure are not yet fully understood, and exposures in humans are mostly uncharacterized. Appropriate exposure control strategies to protect workers are still being developed and evaluated, and regulatory approaches rely largely on industry self-regulation and self-reporting. In this context of soft regulation, the authors sought to: 1) assess current company-reported environmental health and safety practices in the United States throughout the product life cycle, 2) consider their implications for the manufactured nanomaterial workforce, and 3) identify the needs of manufactured nanomaterial companies in developing nano-protective environmental health and safety practices. Analysis was based on the responses of 45 U.S.-based company participants in a 2009-2010 international survey of private companies that use and/or produce nanomaterials. Companies reported practices that span all aspects of the current government-recommended hierarchical approach to manufactured nanomaterials' exposure controls. However, practices that were tailored to current manufactured nanomaterials' hazard and exposure knowledge, whether within or outside the hierarchical approach, were reported less frequently than general chemical hygiene practices. Product stewardship and waste management practices-the influences of which are substantially downstream-were reported less frequently than most other environmental health and safety practices. Larger companies had more workers handling nanomaterials, but smaller companies had proportionally more employees handling nanomaterials and more frequently identified impediments to implementing nano-protective practices. Company-reported environmental health and safety practices suggest more attention to environmental health and safety is necessary, especially with regard to practices that can cause external effects. Given reported impediments, smaller companies may especially benefit from more attention. However, the manufactured nanomaterial workforce within smaller companies is particularly difficult to identify and hence locate, posing challenges to developing and enforcing appropriate workplace environmental health and safety. [Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resource: a file containing Survey of Current Health and Safety Practices in the Nanomaterial Industry and a file containing figures.].

Sodium bicarbonate supplementation improves hypertrophy-type resistance exercise performance.

The aim of the present study was to examine the effects of sodium bicarbonate (NaHCO(3)) administration on lower-body, hypertrophy-type resistance exercise (HRE). Using a double-blind randomized counterbalanced design, 12 resistance-trained male participants (mean ± SD; age = 20.3 ± 2 years, mass = 88.3 ± 13.2 kg, height = 1.80 ± 0.07 m) ingested 0.3 g kg(-1) of NaHCO(3) or placebo 60 min before initiation of an HRE regimen. The protocol employed multiple exercises: squat, leg press, and knee extension, utilizing four sets each, with 10-12 repetition-maximum loads and short rest periods between sets. Exercise performance was determined by total repetitions generated during each exercise, total accumulated repetitions, and a performance test involving a fifth set of knee extensions to failure. Arterialized capillary blood was collected via fingertip puncture at four time points and analyzed for pH, [HCO(3)(-)], base excess (BE), and lactate [Lac(-)]. NaHCO(3) supplementation induced a significant alkaline state (pH: NaHCO(3): 7.49 ± 0.02, placebo: 7.42 ± 0.02, P < 0.05; [HCO(3)(-)]: NaHCO(3): 31.50 ± 2.59, placebo: 25.38 ± 1.78 mEq L(-1), P < 0.05; BE: NaHCO(3): 7.92 ± 2.57, placebo: 1.08 ± 2.11 mEq L(-1), P < 0.05). NaHCO(3) administration resulted in significantly more total repetitions than placebo (NaHCO(3): 139.8 ± 13.2, placebo: 134.4 ± 13.5), as well as significantly greater blood [Lac(-)] after the exercise protocol (NaHCO(3): 17.92 ± 2.08, placebo: 15.55 ± 2.50 mM, P < 0.05). These findings demonstrate ergogenic efficacy for NaHCO(3) during HRE and warrant further investigation into chronic training applications.

Serotonin transport kinetics correlated between human platelets and brain synaptosomes.

RATIONALE: Blood platelets have been used extensively as a model system for investigating the role of the serotonin transporter (SERT) in various psychiatric disorders, especially depression. However, to date, it is not known whether platelet serotonin (5-HT) transport would be related to that in brain. OBJECTIVES: We examined 5-HT transport kinetics simultaneously in human blood platelets and human cortical brain synaptosomes to determine whether they were correlated. METHODS: Blood platelets and synaptosomes were obtained from 25 patients undergoing epileptic surgery. Synaptosomes were obtained from normal margins of surgical neuropathology specimens of anterotemporal cortex. RESULTS: Platelet SERT V(max) was significantly correlated with brain SERT V(max) on linear regression (r=0.58, p<0.005), after controlling for the confounding effects of gender (t=-2.4, p=0.025) and time of day (t=2.1, p<0.05). Consistent with previous observations, there was a negative correlation between the maximum velocity (V(max)) of platelet 5-HT transport and pO2 (r=-0.52, p<0.01). Females had a significantly higher pO2 than males (F=4.9, p<0.05). After accounting for gender differences, addition of pO2 did not add further strength to the regression, given the aforementioned gender differences in pO2. The correlation between unadjusted values for platelet vs brain SERT V(max) was r=0.3, p=0.06. CONCLUSIONS: These results suggest that a relationship may exist between 5-HT transport in platelets and cortical synaptosomes, when appropriate controls for confounding factors are employed.

Open-label risperidone for Asperger's disorder: negative symptom spectrum response.

OBJECTIVE: Asperger's disorder consists of negative symptoms similar to those seen in schizophrenia, autism, schizoid personality disorder, and schizotypal personality disorder. We investigated whether risperidone, which is effective in treating the negative symptoms of schizophrenia, would improve such symptoms observed in Asperger's disorder in a prospective, open-label trial. METHOD: Thirteen male patients aged 6 to 18 years who were diagnosed with Asperger's disorder by DSM-IV criteria were enrolled in a 12-week, prospective, open-label pilot study from March 13, 2002 to August 11, 2003. All subjects were started on risperidone 0.25 mg twice per day. Doses were increased based on clinical indication and tolerability. The primary efficacy variable was the Scale for the Assessment of Negative Symptoms (SANS). Each subject's baseline score served as his control. Secondary efficacy measures included the Positive and Negative Syndrome Scale, Brief Psychiatric Rating Scale, Montgomery-Asberg Depression Rating Scale, Global Assessment Scale, and a modified Asperger Syndrome Diagnostic Scale. RESULTS: We found a statistically significant improvement from baseline for last-observation-carried-forward (LOCF) analyses as well as for analyses of 12-week completers (N = 9) in our primary outcome measure, SANS scores (F = 13.41, p < .0001 for 12-week completers; F = 9.64, p < .0001 for LOCF). We also found statistically significant improvement in all secondary efficacy measurements (F values range, 8.41 to 15.73, p values range, < .0001 to < .005 for 12-week completers; F values range, 6.53 to 7.75, all p < .0001 for LOCF). CONCLUSIONS: Subjects' symptoms significantly improved after risperidone. The open-label nature of this small pilot study suggests caution in interpreting these data, but the results suggest that placebo-controlled trials should follow.