Identification of mothball powder composition by float tests and melting point tests
| Autor: | Ka Yuen Tang |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Float (project management)
Materials science Metallurgy Paradichlorobenzene 030208 emergency & critical care medicine General Medicine Naphthalenes Chlorobenzenes Toxicology Camphor 03 medical and health sciences Salt solution chemistry.chemical_compound 0302 clinical medicine chemistry Melting point Transition Temperature Composition (visual arts) 030212 general & internal medicine Mothball Powders Naphthalene |
| Zdroj: | Clinical Toxicology. 56:626-632 |
| ISSN: | 1556-9519 1556-3650 |
| DOI: | 10.1080/15563650.2017.1406096 |
| Popis: | The aim of the study was to identify the composition, as either camphor, naphthalene, or paradichlorobenzene, of mothballs in the form of powder or tiny fragments by float tests and melting point tests.Naphthalene, paradichlorobenzene and camphor mothballs were blended into powder and tiny fragments (with sizes 1/10 of the size of an intact mothball). In the float tests, the mothball powder and tiny fragments were placed in water, saturated salt solution and 50% dextrose solution (D50), and the extent to which they floated or sank in the liquids was observed. In the melting point tests, the mothball powder and tiny fragments were placed in hot water with a temperature between 53 and 80 °C, and the extent to which they melted was observed. Both the float and melting point tests were then repeated using intact mothballs. Three emergency physicians blinded to the identities of samples and solutions visually evaluated each sample.In the float tests, paradichlorobenzene powder partially floated and partially sank in all three liquids, while naphthalene powder partially floated and partially sank in water. Naphthalene powder did not sink in D50 or saturated salt solution. Camphor powder floated in all three liquids. Float tests identified the compositions of intact mothball accurately. In the melting point tests, paradichlorobenzene powder melted completely in hot water within 1 min while naphthalene powder and camphor powder did not melt. The melted portions of paradichlorobenzene mothballs were sometimes too small to be observed in 1 min but the mothballs either partially or completely melted in 5 min. Both camphor and naphthalene intact mothballs did not melt in hot water.For mothball powder, the melting point tests were more accurate than the float tests in differentiating between paradichlorobenzene and non-paradichlorobenzene (naphthalene or camphor). For intact mothballs, float tests performed better than melting point tests. Float tests can identify camphor mothballs but melting point tests cannot. We suggest melting point tests for identifying mothball powder and tiny fragments while float tests are recommended for intact mothball and large fragments. |
| Databáze: | OpenAIRE |
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