INDUSTRIAL HYGIENE The effect of some metals, such as mag nesium and zinc, appears to be transient Only limited data are available on the exotic and rare earth metals Although the dusts and fumes from metals with low toxicity do not need as much atten tion as the dusts and fumes from highly toxic metals, they should not be neglected or disregarded The metals with low toxicity are more readily controlled because greater amounts can be tolerated, but their dusts and fumes should be kept at reasonable levels since excessive amounts of any of them can be harmful Inhalation of the dust of lead compounds is the most common mode of entry of lead mto the system, and ingestion of lead com pounds can add to the problem if personal hygiene is poor Workers therefore should be encouraged to wash thoroughly before eat ing, and lunchrooms should be apart from work areas Lead is a normal constituent of plants and animals, and people ingest and excrete it daily even though they are not exposed to lead in their daily work When intake rates exceed the normal excretion rates, however, lead bmlds up m the body When the accu mulation readies a sufficient level, symptoms of poisoning or intoxication appear The concentration of airborne lead should there fore be kept below the threshold limit be cause of lead's high toxicity and its tendency to accumulate in the human system Beryllium intoxication is a severe system ic disease that can result from the inhalation of the dust or fume of metallic beryllium, beryllium oxide, and soluble beryllium com pounds (There is no evidence of intoxica tion from the ingestion of insoluble com pounds ) Only the inhalation of the beryl lium-bearing dusts or fumes produces sys temic disease Accordingly, control of such dusts and fumes to keep them below the concentration specified by ACGIH (Ameri can Conference of Governmental Industrial Hygienists) threshold limit values is a basic protective measure When the soluble salts of beryllium, espe cially beryllium flounde, contact cuts or abrasions on the skin, deep ulcers may be formed which heal very slowly, and com plete surgical excision of the ulcer is some times required to effect healing.

Z sold him the lead.

However, the paper deals directly with o ccupational lead exposure, and only indirectly with the exposure of public.

and thereby asking sure that intercurrent illnesses of another type might not be mistaken for lead .

I trust you will not have the opportunity of seeing any cases of tetraethyl lead poisoning.

Any individual, corporation, association, partnership or other organiza tion admitted to membership which is engaged within the United States in lead mining, smelting and refining, manu facturing or consumption, or which is engaged in one or more of such activities outside the United States and markets lead or lead products within the United States, shall be a member of the Corporation.

As I have indicated previously, the published material does not cover the scope or the productivity of the work done; and I am working toward a prolonged period of study and writing which will enable me to prepare a monograph on lead (occurrence in nature, metabolism in man^ in health and disease, clinical lead poisoning, diagnoses and therapy, industrial hygiene in the lead trades, lead in the general environment of man as a problem of public health, supplementary information as to certain physiological indices based on daily observation of industrial employees.and experimental subjects).

., entitle "Lead in the Biosphere," etc., etc.

I trust you will not have the opportunity of seeing any cases of tetraethyl lead poisoning.

Hellings - NA During Cliff Hellings visit this week we discussed the blood lead and ZPP level of (shift supervisor) His six month blood lead level is 52 and his Zinc Protopor phyrin level runs at 600-700.

The only means we have of determining the probable quantities of lead in the intact human body'and their significance for hygienic or diagnostic purpose, is that of obtaining appropriate samples of blood and urine without Inducing any change of any kind in the pattern of distribution of the lead in the body.

(2) 'Added lead* la daflaad as the ndditlea af lead aaapaaada aa catalysts, ata. aad daaa ||1 laalads lead ceataaiaanta tbat ai|pit be present la laarta, placets, ata.

NOTIFY THE LEAD OPERATOR FOR FURTHER INSTRUCTIONS. 6.

The excretion of lead per twenty-four hours has been shown by our data to vary quite as widely as the concentration.

As I have indicated previously, the published material does not cover the scope or the productivity of the work done; and I am working toward a prolonged period of study and writing which will enable me to prepare a monograph on lead (occurrence in nature, metabolism in man^ in health and disease, clinical lead poisoning, diagnoses and therapy, industrial hygiene in the lead trades, lead in the general environment of man as a problem of public health, supplementary information as to certain physiological indices based on daily observation of industrial employees.and experimental subjects).