A course in chemical hazards - Journal of Chemical Education (ACS

In the Spring of 1972, a new courses in chemical and industrial hazards was offered at City College of New York for undergraduates in chemistry. Altho...
2 downloads 0 Views 3MB Size
in the Chemical laboratory Edited by NORMAN V. STEERE, 1 4 0 Melbourne Ave., S:E. Minneapolis, Minn. 5541 4

CXII. A Course in Chemical Hazards Michael E. Green, Ph.D., Assistant Professor, Department of Chemistry. City College of the City Universityof New York, New York, N. Y. 10031 In the Spring of 1972, a new course in chemical and industrial hazards was offered a t City College of New Yark for undergraduates in chemistry. Although the course was new a t City College, the need for such a course is scarcely new, and such courses are not common a t colleges and universities in the United States.

I. INTRODUCTION The recorded history d occupational diseases stretches a t least baek to Biblical times, with miner's illnesses being particularly well known. With the industrial revolution occupational illnesses became much more widespread, and now appraximately 14,000 U.S. workers die from officially-reported injuries and illnesses associated with work. According t o a study prepared for the U S . Department of Labor, some twenty five million serious injuries go unreported each year.

II. HAZARDS AND NEED FOR INSTRUCTION More than 40,000 chemical substances are in commercial use in the United States, and a myriad of new substances are being synthesized regularly. Although most of these chemicals are used in small amounts and few locations, some are toxic, corrosive, flammable or otherwise hazardous. However, chemists and industrial workers exposed to chemical hazards tend to take a cavalier attitude toward sueh exposures. The chemist should be able to consider the hazards of exposure since many commercially-prepared laboratory chemicals are labelled to indicate hazardous properties and precautions, but many hazardous industrial chemicals are not so labeled and workers handling these chemicals are often exposed to bulk quantities over extended times. Chemical hazards in undergraduate laboratories do not seem to be considered by chemistry instructors, and students consequently do not learn about sueh hazards or necessary precautions and control measures. Industrial workers become inured to dangerous conditions by habit, by the fact that the hazards are rarely explained to them, and by the fact that there is little that they can do in any case. Therefore, the workers continue to pack the bottles

which will he labelled as hazardous, with hardly any protection for themselves. In addition, there are a considerable variety of other problems in the industrial environment including dust, noise, heat and radiation. Of these hazards, only radiation is likely t o prove a serious difficulty in the laboratory. There is now an increased interest in health and safety in the industrial area. The Occupational Safety and Health Act of 1970 (OSHA) went into effect on April 28, 1971, regulating working conditions in essentiallv all workolaces in the U.S.. except those of gmcrnmenral agenri~c.P w \ ~ u u r l ) .under the \\alch-Htdr? . k t , only a small fmttion of u,orkerr in this country had been even nominally covered. The consequences of the increased interest in occupational safety and health will be of importance to the practising chemist, and therefore t o the chemistry student. Combined with the growing consumer movement, this increased interest will require that the industrial chemist especially be concerned with chemical toxicity. So far, however, there appears to be little in the way of reaction or of new courses in chemistry departments to deal with this set of problems. Although there are programs in aceupational health in several universities, the National Institute of Occupational Safety and Health (NIOSH) has pointed to a national shortage of trained occupational health professionals a t all levels. With most present chemistry curricula, it is not likely that chemists will contribute significantly to alleviating occupational health problems. In fact, there are relatively few chemists who show that they are aware of the toxicity of even the most common suhstances they handle. Benzene is one eaample-it is known to cause liver and kidney damage in the parts per million range and all forms of leukemia have been observed in workers exposed to benzene (1, 3). Our experience has been that relatively few students, including graduate students, appear t o be even aware of the precautions needed to handle benzene. In practice, the situation appears t o be even worse. Most university laboratories do not monitor the concentrations of solvents, gases or volatile chemicals (e.g. benzene, H2S, Hg) that faculty, students, or technicians are exposed to. One consequence is that students will graduate with the same disregard for hazards that has been tradi-

feature

tional. What education on monitoring there has been for chemists seems to have been casual and informal for the most part. Neither has there been much consideration of the problems of monitoring exposures of chemical workers. We have already noted that the profession which normally deals with exposure monitoring, Industrial Hygiene, is not heavily populated. For example, there were about fifty industrial hygienists (2. 3) (in addition to less than 1000 compliance officers) employed in the enforcement of OSHA, for the 4.1 million workplaces in the country, as of January 1, 1973. (The compliance officers normally must call in an industrial hygienist to confirm serious exposure limit violations.) The small number of industrial hygienists in enforcement is not entirely due to the lack of industrial hygienists, of course. However, it does suggest the level of activity in this field. Occupational health training programs do exist a t several universities although Federal funding is being terminated, and there are now about six Chairs of Oceupational Medicine in U.S. medical schools. Even though industrial hygiene may expand appreciably in the next few years i t seems clear that the large majority of workers and chemists exposed to chemical and physical hazards will have to depend on themselves for preliminary determinations of their own levels of exposure. While it may seem unusual to expect workers to even assist in their own monitoring, much of the equipment required is no more difficult to operate than machine tools which workers use all the time. Some equipment, such as noise survey meters, are extremely easy to use, judging from experience gained from the OCAW and UAW courses mentioned below. Although complete determination of levels of exposure, obviously requires the expertise of the industrial hygienist, there are not enough industrial hygienists to go around. With a few hundred dollars worth of equipment, which most chemistry departments and many labor unions can afford, useful estimates of exposure levels can he made. Methods of estimating exposure levels in the workplace are described in an elementary hook now available 131.

Ill. DEVELOPMENT OF THIS COURSE Some recent efforts t o provide information on oceupstional hazards have been made bath a t Rutgers Labor Center and a t City College. A course prepared far industrial workers with little technical baekground, was offered during the Fall 1971 (Continued onpogeA158)

Volume 51, Number 3, March 1974

/

A157

Safety

. ..

semester a t Rutgers Labor Center. The students were mostly members of the Oil, Chemical, and Atomic Workers International Union (OCAW), principally shop stewards and safety committee members. Anthony Mazzochi, Citizenship and Legislative Director of OCAW, played a major role in setting up the arrangements for the course. The course consisted of a discussion of chemical and physical hazards, some basic physiology including effects of the hazards, methods of monitoring hazard levels, requirements for protection, and a brief discussion of the law and the history of the field. Teaching the course required chemists, a physicist, a physician, an engineer, and a lawyer. The course met for thirteen sessions of two hours each, one evening per week. A similar course was taught during the Spring 1972 semester for United Auto Workers members, OCAW members, and members of other unions. There were minor differences in the topics covered because of the importance of maintaining the relevance of the material to the needs of the workers in the particular industry primarily involved in the course. Each session included a good deal of discussion, with examples from the plants represented. For example, workers who packed organo-phosphorous insecticides discussed their problems, what acetylcholinesterase does, and possible effects of the insecticides on acetylcholinesterase activity. The course a t City College was somewhat different. Essentially the same topics were covered, and approximately the same schedule was followed (14 weeks, one evening per week for two hours). The course carried two credits. Because it was an evening course, most of the students worked, and thus had some experience with industrial hazards. However, this course was taught mainly to juniors and seniors majoring in chemistry and a considerable increase in detail was expected to be possible. The students were required t o prepare papers on topics of interest to them, and the course carried two credits. Some of the students had experience in industry so their papers proved to be fairly useful work and also showed how little had been done in many occupational fields. For example, one student who had worked in the fur industry found a relatively high incidence of asthma, presumably related to fur dust, among a small group of worksrs. By reasoning from a visual inspection of the loft in which they worked, and comparing known data on house dust, he was able to suggest the existence of dustcaused asthma as an occupational hazard m the fur industry. The student was unnhle ta find any previous work in his rearch of the literature. Another student iiscussed safety hazards and health problems from inks and dyes in his plant. The course included the following sections: (1) An introduction t o the problems, m d some basic definitions and nomencla:ure (e.g. TLV, dB scales). (2) Monitoring techniques and prohlems: This included a discussion of instrunentation, and of the necessity of care in A158

/

Journal of Chemical Education

getting adequate average examples. Also instantaneous (grab) sampling techniques were discussed, together with appropriate instruments for this purpose. Since the instruments for these purposes are not normally used by the student (midget impingers and appropriate pumps, universal tester pumps, etc.), these had to be described in some detail. However, since the principles are quite simple and generally familiar from elementary gas law calculations, there was no need for a n extended theoretical discussion. Since the analytical techniques needed after the samples are collected are mostly standard, they were not diseussed in great detail. In this particular class, the students were far enough along in their work t o have handled standard analytical instrumentation. However, it is not critical for the purposes of this course if students do not know how to do sample analysis; i t is only important that they understand sampling, and know that samples can be analyzed. (3) Physical hazards, and monitoring physical hazard: Noise and ionizing radiation are the most obvious physical hazards, but thermal stress and same forms of non-ionizing radiation needed to be discussed as well. (Dust was treated as a chemical hazard in this course because of similarities in sampling techniques.) Nonionizing radiation included microwaves, which are gaining more extensive industrial application in addition to usage in commercial and domestic ovens. Most students were already aware of the hazards of ultraviolet light and ionizing radiation so that only a review of ionizing radiation standards and a brief description of monitoring instmmentation was included. Thermal stress, both heat and cold, was discussed in qualitative terms in the absence of adequate criteria relating temperature, radiation temperature, humidity, and physical effort to stress. (Some engineering standards have existed for decades but NIOSH is just now issuing the first set of criteria documents for regulatory standards.) As probably the most prevalent industrial hazards, noise was discussed in some detail, including monitoring instruments, averaging problems, and the question of the appropriateness of the present standard of 90 dB per eight hour day in the light of evidence that damage appears to begin above 85 dB. (4) Chemical hazards: Some of the most common serious hazards were discussed in detail, such as heavy metals, aromatic hydrocarbons, and toxic and nuisance dusts. A few common groups of chemicals were discussed in terms of the Threshold Limit Values (TLV), which have been set for about 450 compounds. When a course similar t o this is taught to workers, the workers determine which specific compounds are discussed, according to what is used in their plants. Since this course was offered to chemistry students, emphasis was placed on benzene, mercury, and other substances commonly used in student laboratories. The discussion included monitoring methods, possible substitutions (e.g. toluene for benzene) levels of toxicity, similar hazards, and physiological effects to be expected from groups of compounds such as heavy metals.

(5) Physiology and medical effects: Three sessions were devoted to an introduction t o the physiology of the target organs of various toxins. In these sessions the central nervous system, liver and kidneys, and heart and lungs were discussed. A brief description was given of the structure of the organ, the effect of various t m ins, the type of symptoms to be expected, and the appropriate medical tests. Since there may he controversy over the medical tests selected, there was discussion of coal worker's pneumoconiosis ("black lung") in which the Social Security Administration had been relying on X-rays to establish disability, although arterial blood gas tests may be required to establish a diagnosis. Since medical questions were expected, this section was given by an MD, Dr. Michael Borecky. (6) Welding: Although welding is not a problem for chemistry students, one leeture was included on this topic because of its industrial ubiquity. Welding fumes may contain highly toxic species, (e.g. Ni(CO)r, when nickel alloy steels are welded) and welding is often carried out without proper ventilation. Dr. Steven Stellman gave this lecture. (7) Ventilation and respirators: This topic included a n outline of the design of hoods, and the use of gas masks and other breathing apparatus. Mr. James Weeks, an industrial engineer, gave this session. (8) The law: The Occupational Safety and Health Act and its enforcement were discussed within the limitations of a two hour session. Emphasis seemed most appropriately placed on the worker's rights under the law, including means of calling for a n inspection. Some severe limitations on possibilities of enforeement had to be considered as well. Mr. Howard Thorkelson, a lawyer, presented this topic. (9) Inspection of school laboratories: Using the available instrumentation-a noise meter and a universal tester pump with color reaction tubes for grab samples of benzene and cyclohexane, the class spent a two hour session going through an organic laboratory, and looking a t a n analytical laboratory in which there was no class. The henzene tests chiefly illustrated difficulties in the sampling technique. However, in some parts of the laboratory cyclohexane was close t o or over the limit for a n allowable eight hour average exposure. The determination near a refluxing operation being carried on outside of a hood could only he approximately quantitative with the apparatus used. Excessive noise, over 110 dB compared with a n instantaneous ceiling of 116 dB, was only found when drying glassware with a n air jet. (Drying glassware is a fairly short operation; hence it is appropriate t o compare with the instantaneous ceiling rather than the 8-hour average limit of 90 dB.) The analytical laboratory had droplets of mercury in a few crevices. If better equipment becomes availahle, more time should he devoted to this part of the course. Although no really catastrophic problems were found, it seems safe to assume the absence of a high degree of safety or health consciousness among the students, or others. The text used for both the courses a t Rutgers Labor Center and City College of New York was Industrial Hazards ( I ) , a n

elementary introduction covering the same topics discussed in the course. Since the level of the text was appropriate mainly for industrial workers without previous background in chemistry, some additional material had to he introduced for ehemistry students. Much of the material was sufficiently unfamiliar t o the chemistry students that less supplementation was necessary than had been expected. An expanded and revised version of the text is now available (3).

IV. CONCLUSIONS While the hazards in student laboratories are not comparable quantitively to those to which industrial employees are exposed, and the laboratory exposure time is about one-tenth of industrial exposure time, the exposure problems and hazards are similar. If undergraduate laboratory hazards are not considered and students are not taught to recognize them, their education is not complete and the students are not going to recognize such hazards after graduation, unless they receive further training. A discussion of the chemical and nhvsical hazards associated with lah. oratory and mdustrlal wurk should become a formal part of c h r m i i t r s curricula land other scipnre ~ u r n r u l a. ChemmtL s h d d take a responsibility to become aware of chemical environmental hazards and should cooperate with other professionals to help laboratory and industrial workers understand the chemical and physical hazards they may be exposed to.

.~

ACKNOWLEDGEMENTS I wish to thank Dr. Jeanne Stellman for reading the manuscript and suggesting various corrections. I also wish to thank Dr. Michael Borecky, Dr. Steven Stellman, Mr. James Weeks, and Mr. Howard Thorkelsan for their participation in the City College course.

REFERENCES 111 J. M. Stellman, D. Kotelehuek. S. Daum. M. E. Green. S. 0. Stellmsn, A. Vosk, D. Callen, and M. Handleman. Induatriol Hoxordr, IDishict 8. Oil.

. .

(2) J. M. Stellman. private commuoication

(3) J. M. Stellmen and S. Daum, ods. "Work i s Dangerour to your Health." (New York, Pantheon Preu, 1973)

AVAILABLE MARCH 31. 1974 Salety in the Chemical Laboratory-Volume Edlted bv Norman V. Steare 160 pp..'$5.50

3

-----------

Volume 1. 1964-67: Volume 2. 1967-70: Volume3. 1971-73: Combination price; Combination price; Combination price;

132 pp. 132 pp. 160 pp. 3 volumes -Val 1 & 2 Vol. 2 8 3

$3.00 $3.50 $5.50 $10.50 $5.75 $8.00

Order, prepaid, from Chemical Education Publishing Co.. 20th and Norfhampton Sts.. Eastan. Pa. 18042

Volume 51, Number 3, March 1974

/

A159