Naphthalene is a crystalline aromatic hydrocarbon usually obtained by distillation of coal tar. Once used as a moth repellent, it is now important as a reactant in the production of phthalic anhydride, which in turn is used for making plasticizers, alkyd resins, and polyester resins. Other fumigant uses of naphthalene include use in soil as a fumigant pesticide, and in attic spaces to repel animals. In the past, naphthalene was administered orally to kill parasitic worms in livestock. In humans, exposure to large amounts of naphthalene may damage or destroy red blood cells. Humans, particularly children, have developed this condition after ingesting mothballs or deodorant blocks containing naphthalene. Some of the symptoms of naphthalene poisoning are fatigue, lack of appetite, restlessness, and pale skin. Exposure to large amounts of naphthalene may also cause nausea, vomiting, diarrhea, blood in the urine, and jaundice (yellow coloration of the skin).