of (lie capabilities of micriK)rjj:misms. cultured (issue 
cells and parts (hereof." 
M Kikm/i v'l .»! . S.ilc lM<Mvclinnlocv 
3. Tlic fields covered 
Only safety aspects specific to biotechnology arc 
considered. These include: 
— pathogenicity: the potential ability of living organ- 
isms and viruses to infect man. animals, and plants 
and to cause disease; 
— toxicity and alkrgy associated with microbial 
production; 
— other medically relevant effecss (e.g., increasing 
the environmental pool of antibiotic-resistant mi- 
croorganisms); 
— problems associated with the disposal of spent 
microbial cell masses and the purification of effluents 
from biotechnological processes; 
— safety aspects associated with contamination, 
infection or mutation of process strains; 
— safety aspects associated with the industrial use of 
microorganisms containing in vitro recombinant 
DNA. 
Excluded are hazards common to other industrial 
proce s ses, e.g., handling of raw materials, allergic 
reactions and intoxications caused by chemicals, 
mechanical and engineering problems, fire and 
explosion risks associated with gases such as meth- 
ane, solvents such as ethanol, and dry powders. 
4. The objects of safety assessment 
As in all other industries, two groups have to be 
considered: 
— persons who work in biotechnology laboratories 
or industrial production units; 
— persons, animals, plants, and environments 
exposed -to emissions from biotechnology laborato- 
ries or industrial production units. 
S. Problems specific to biotechnology 
5.1 The pathogenicity of some microorganisms 
This is defined above as the potential ability of living 
organisms and viruses to irrfect man and other higher- 
life forms and cause disease. A small proportion of 
the very large number of microorganisms known to 
science have this ability. Such infections and diseases 
are the result of interactions between the parasite and 
the host and it is not possible to conclude that a 
particular microorganism or virus will always cause 
disease because pathogenicity ubvuys depends on the 
genetic make-up and physiological state of both host 
and parasite as well as other laciors. including the 
infecting dose and the portal of entry into the 
host. 
Very few of the microorganisms and viruses that 
arc capable of causing disease arc used in industry 
and these arc usually employed in the manufacture of 
vaccines or diagnostic reagents. Examples include 
Dordetella pertussis. Mycobacterium tuberculosis, and 
the virus of foot and mouth disease. The scale of 
operation is usually relatively small, with culture 
vessels of a few cubic metres capacity. Safety is 
ensured by physical containment of the organisms 
during cultivation, followed by inactivation before 
use. 
The majority of microorganisms used by industry 
are harmless; indeed, many are used in the prepa- 
ration of human and animal food. These include the 
ubiquitous yeasts, and, more recently, some bacteria 
and fungi, for the manufacture of beer, wine, 
enzymes, antibiotics, hormones, etc. on a scale of up 
to 1,000 t/week in any one manufacturing plant with 
culture vessels having capacities in excess of 1 ,000 m 3 . 
Information about the safety of many processes is 
based on practical experience, often gained over 
periods as long as a 100 years. 
The problem fadng a manufacturer who wishes to 
introduce a new technological process is to detemfine 
whether the organism on which it is based is capable 
of causing disease, and if it is in deciding an 
appropriate method of containment. In addressing 
this problem the manufacturer will first have the 
organism classified to genus and spedes. This will 
permit an initial assessment of its probable behaviour 
as a pathogen, based on existing knowledge of the 
Organism itself and of related spedes. This assess- 
ment may then be supplemented by pathogeniaty 
tests. 
Clinical and research laboratories in which mi- 
croorganisms of all kinds, induding' pathogens, are' 
handled routinely have adopted dassifications which 
grade them into Risk Clas s e s , usually 1—4 in 
increasing order of pathogeniaty, and on the basis of 
hazard to worker and general public. 
A number of organisations, induding the Nether- 
lands Microbiological Sodety [3], the German Health 
Authorities [4], The World Health Organisation (5], 
the United States Department of Health and Human 
Services {6], and the United Kingdom Department of 
Health and Sodal Security and- Health and Safety 
Executive [7] have introduced such dassifications. 
Some uncertainties about the risks involved in 
handling some organisms are reflected in the lack of j 
unanimity about their allocation of organisms to class 
or category. 
Recombinant DNA Research, Volume 13 
[ 362 ] 
