37 



possible toxicity of these newly created materials in order to determine 

 whether it is legitimate to dispose of them to the environment at all, 

 or whether they should be rigorously recylcled without any release to 

 the environment. 



There is a list of the type of investigations that must be made in 

 order to evaluate the effect of pollutants in marine environment, and 

 this little box in the middle, the synergism and antagonism is one that 

 we knoAv verv. verv little about. 



If two different pollutants are added to the system, will they have 

 an additive effect, will they interfere with each other in action on the 

 environment, and so on ? We really do not know. 



There is a legitimate receiving capacity of any environment for any 

 natural material. I am not sure that that can be extended to some of 

 these manmade materials like the polychlorinated biphenvls and so 

 forth. There is a natural receiving capacity which is that capacity 

 which allows the ecosvstem to recycle the material in a natural way. 



This involves knowledge of the circulation, mixing of the waters, 

 decomposition of the material and the way in which it chansres. Of 

 course, there is the problem of its possible return to man in his food. 



Some of these materials get incorporated in the sediments, which 

 may be their ultimate fate, but if thev are stirred up again at a later 

 time, as they are by dredging of harbore and estuaries, they may get 

 returned to the system and create, again, a source of the material for 

 future pollution. 



I would like to conclude my very general statement with the remark 

 that it is my conviction that the onlv ultimate solution to the problems 

 of pollution is to recycle the material that we produce and use in our 

 civilizaHon. Discharging these materials to the environment is both 

 wasteful of our natural resources, and causes undesirable impacts upon 

 the ecosvstem. 



Complete recvcling is probablv an unattainable goal, but certainly 

 everv effort should be made to recycle materials as completely as possi- 

 ble, not only to conserve our natural resources, but also to prevent the 

 further deterioration of our environment which we must preserve for 

 the ultimate benefit of man. 



Thank you, ]\Ir. Chairman. 



Senator Hollixgs. Dr. Ketchum, is the recycling recommendation 

 that you make a realistic one within the context of, say, the next 25 

 years ? Could we do that ? 



Dr. Ketchum. I think in manv cases it is realistic. I think that if 

 industry really devoted the attention to recycling of substances within 

 the plant before they release it to the environment, that a great deal can 

 be done. 



This is being imposed by laAv in the case of mercury and in the case 

 of arsenic, and of various otlier toxic materials, and suddenly they 

 discovered it is possible to do it. 



Sometime it can be done, at some expense, to be sure. But I will not 

 be surprised when industry devotes its attention to this, if they do not 

 make a profit out of it. 



Senator Hollixgs. In what sense would they be making a profit? 

 I would like to sell that idea to them. 



Dr. Ketciii'm. Well, mercury is a very expensive element, and every 

 bit that you waste is throwing away a certain amount of money. If 



