(a) Pottery and earthenware processes

(bo) Lead mining, smelting, and refining

{c) Gasoline--(Ethyl gas)

(ad) Printing trades

(e) Miscelleneous: drinking water; beer made in lead lined vats;
paint; face powder and cosmetics.

Absorption

Respiratory tract most frequent and serious. Dust or fumes is the
carrier of the substance. Enters blood directly in lungs.

 

Intestinal tract--through liver into the circulation.

 

Skin--not as frequent--though it occurs from paints, cosmetics and
hair dye.

Storage in Body

 

Lead is stored in the bones. Safely stored without ill effects as
long as calcium balance of body is positive amd a normal hydrogen concen=
tration of the blood.

Excretion=—through feces ard urine.

Symptoms
Acute form--Intense colic, diarrhoea, rapidly developing anemia,
convulsions, and mental symptoms.

Chronic form-Anemia, constipation, colic, paralysis (wrist drop),
"blue line" on gums, muscular vain, and swelling of joints.

Maternal and Congenital--Lead is a race poison, causing:

{a) Sterility
(b) Prematurity and still births
{(c) Dwarfing

Prevention rests here, as in control of cammunicable diseases, upon
a knowledge of the sources and modes of infection: {a) dust, (b) fumes,
(c) by hands to gastro-intestinal tract.

(a) Prevention of dust and removal of fumes
(bo) Cleanliness of body clothing and surroundings
{c) Milk drinking

Arsenic is a source of a considerable amount of occupational poison-
ing.
The principal sources of arsenic poisoning are:

{a) Lead smelting

(b) Paris green manufacture

{c) Sheep dip

(d) Hides, feather, and fur processing
(e) Criminal use