MadSci Network: Science History |
I tried searching various chemical information databases to find the answer to this question. Unfortunaly I couldn't find a definitive answer.
What I can tell you is that there are actually two kinds of moth balls; the original (first used in cone form in the early 1800's) contained naphthalene, which had been discovered by British chemsit John Kidd in the late 1700's from coal tar distillation. The are numerous references to the use of naphthalene as an insect repellent and insecticide as early as 1850. Naphthalene however is very flammable and extremely poisonous to humans as well as insects, so a less toxic replacement was sought and developed in the early 1900's using paradichloribenzene. This is what is commonly used today as moth crystals and balls.
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