Suchergebnisse

UnlabelledThe plasma display panel (PDP) is rapidly becoming obsolete, contributing in large amounts to the electronic waste stream. In order to assess the potential for environmental pollution due to hazardous metals leached from PDP glass, standardized leaching procedures, chemical speciation assessments, and bioavailability tests were conducted. According to the Toxicity Characteristic Leaching Procedure (TCLP), arsenic in back glass was present at 4.46 ± 0.22 mg/L, close to its regulation limit of 5 mg/L. Zn is not available in the TCLP, but its TCLP leaching concentration in back glass is 102.96 ± 5.34 mg/L. This is because more than 90% of Zn is in the soluble and exchangeable and carbonate fraction. We did not detect significant levels of Ag, Ba, or Cu in the TCLP leachate, and the main fraction of Ag and Ba is residual, more than 95%, while the fraction distribution of Cu changes SEP by SEP. Ethylenediamine tetraacetic acid (EDTA)- and diethylenetriamine pentaacetic acid (DTPA)-extractable Ag, As, Ba, Cu, Zn, and Ni indicate a lower biohazards potential. These results show that, according to the EPA regulations, PDP glass may not be classified as hazardous waste because none of the metals exceeded their thresholds in PDP leachate. However, the concentrations of As and Zn should be lowered in the manufacturing process and finished product to avoid potential pollution problems.ImplicationsThe plasma display panel is rapidly becoming obsolete because of the liquid crystal display. In this study, the leachability of heavy metals contained in the waste plasma display panel glass was first examined by standardized leaching tests, typical chemical speciation assessments, and bioavailability tests, providing fundamental data for waste PDP glass recovery, recycling, and reuse.

Abstract
Background
Pyrethroids have been widely used in the United States and worldwide. Few studies examined the effect of pyrethroids exposure on sleep problems among adolescents.

Objectives
This study investigated the associations between pyrethroids exposure and sleep problems in male and female adolescents.

Methods
The data were used from the National Health and Nutrition Examination Survey 2007–2014. In this study, 3-Phenoxybenzoic Acid (3-PBA) was used as a validated biomarker for pyrethroids exposure. The association between urinary 3-PBA and sleep problems was analyzed using logistic regression models.

Results
A total of 805 adolescents aged 16–20 years old were included in this study. The proportion of sleep problems was higher in females than in males (10.18% vs.7.35%, P = 0.154). A significant interaction was found between sex and 3-PBA (P interaction = 0.021) in the risk of sleep problems. A positive association of 3-PBA exposure with sleep problems was observed in male adolescents after adjusting for all the other covariates (OR = 4.04, 95% CI 1.31, 12.42). No statistically significant association was observed in female adolescents.

Conclusions
A positive association was observed between pyrethroids exposure and sleep problems in male adolescents, but not in female adolescents. More studies are required to confirm our findings.