body shows very low tolerance, and as little as one microgram per gram of tissue causes serious disturbances It has been connected to emphysema and severe irrita- tions of the nasal and bronchial passages, leading to

a chronic cough.

Zine oxide has been reported as being toxic, but these are in older treatises and the effects cited are more likely to have been from contaminations from lead or mercury. Even so, ingested zinc oxide may cause temporary illness.

COMMENTS

This treatise does not presume to be all-inclusive. I have gleaned the information from the bibliography which follows.

My concern is that some of the materials used in con- temporary ceramics are not used in other industries and may not have been completely investigated. All of

this points to the fact that all materials should be treated with respect. Every effort should be made to avoid ingesting ceramic materials, particularly those used in glazes, Smoking or eating in glaze labora- tories should be discouraged and great care should be taken to clean hands and clothes before meals.

Perhaps even more important are complete dust-control measures. Potteries are inherently dusty, and it has been demonstrated that the dust from a wide variety

of materials can cause permanent pulmonary disorders. Frequent sweeping with a dust-collecting compound,

or, perferably, hosing the area often will help. Clay mixing areas should be wel! ventilated with a fan capable of moving sufficient air to prevent a dangerous concentration of solid particles in the air.

Considering the fact that a cure, j.e., complete remission of symptoms, 15 often impossible, adequate

preventative measures are most emphatically needed. 35