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Identification of mothball powder composition by float tests and melting point tests
1a Accident and Emergency Department , Caritas Medical Centre , Sham Shui Po , Hong Kong , China.
Clinical Toxicology (Philadelphia, Pa.)
|November 28, 2017
Summary
Melting point tests accurately identify mothball powder composition, while float tests are better for intact mothballs. These methods help distinguish between camphor, naphthalene, and paradichlorobenzene mothballs.
Area of Science:
- Forensic Chemistry
- Materials Science
Background:
- Mothballs are commonly used household products for pest control.
- Mothballs are typically composed of camphor, naphthalene, or paradichlorobenzene.
- Accurate identification of mothball composition is crucial for safety and environmental assessments.
Purpose of the Study:
- To determine the effectiveness of float tests and melting point tests in identifying the composition of mothballs.
- To differentiate between camphor, naphthalene, and paradichlorobenzene in mothball formulations.
Main Methods:
- Mothball samples (camphor, naphthalene, paradichlorobenzene) were prepared as powder, tiny fragments, and intact balls.
- Float tests were conducted in water, saturated salt solution, and 50% dextrose solution (D50).
- Melting point tests were performed in hot water (53–80°C).
Main Results:
- For mothball powder, melting point tests accurately differentiated paradichlorobenzene from naphthalene and camphor.
- Float tests accurately identified the composition of intact mothballs.
- Camphor powder floated in all tested solutions, while paradichlorobenzene powder partially floated and sank.
Conclusions:
- Melting point tests are superior for identifying mothball powder and small fragments.
- Float tests are more effective for identifying intact mothballs and larger fragments.
- The study provides practical methods for distinguishing common mothball compositions.
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