Only if you eat them or inhale large amounts of the fumes. Ordinary use of mothballs, such as placing them in an attic or storage chest to protect against moths, poses no risk of toxic exposure.

Mothballs were first made from camphor, and later naphthalene. Today, most are composed of the chemical p-dichlorobenzene. All three substances are toxic to humans if eaten or inhaled in large quantities.

P-dichlorobenzene can irritate you skin, throat and eyes. Prolonged exposure may lead to dizziness, weight loss and liver injury.

While people are aware of hazards posed by chemicals in workplaces, less attention has been given to chemicals in the home. Small children are vulnerable to accidental poisoning and during the summer break when children are usually at home, extra precautions should be taken. The elderly are also vulnerable, as aging can lead to a decline in the metabolic activity of vital organs and tissues.

The aged may not be able to eliminate toxins as easily as other people.

Some household areas (see box) may contain poisons which adults take for granted but are within reach of children who may be accidentally poisoned by them.

All these products should be stored safely out of the reach of small children and animals. Never transfer them into food or drink containers, as they may be mistakenly eaten or drunk, with serious results. – World Health.