the expression mutual poisoning as used in the passage suggest that

  The root of problem which bedevil rural dwellers in Nigeria can be traced to the sad fact that work opportunities are so restricted that they cannot work their way out of poverty and misery. Though a great number of Nigerians still live in the villages and small towns, work opportunities exist mainly in the big cities where development efforts are concentrated. The reason usually given for his obvious lapse is that it is easier to establish industries and to find finance and markets to keep them going in the big cities and towns than in the rural areas where productivity is low because of mass illiteracy and poverty.
As capital is the product of human work, rural dwellers who are desperate enough to overcome poverty often leave the villages in search of some kind of existence in the big cities and towns. Therefore, rural unemployment in Nigeria produces mass migration into the cities, leading to a rate of urban growth which seriously taxes the resources of even the biggest cities like Ibadan, Lagos, Abuja and Kano. Form the sad experience of these cities; it is easy to see how rural unemployment can become urban unemployment with the attendant social problems like robbery, overcrowding and the growth of shanties or slums.
Such problems cannot be wished away but will remain with us until deliberate efforts are made to bring health to economic life outside the big cities in order to check the migration of destitute rural dwellers into town and cities that cannot absorb them.
It is necessary; therefore, that at least an important part of the development effort should bypass the bid cities and be concerned with the provision of viable infrastructure in the small town s and villages. In this connection, it is necessary to emphasize that the primary need is workplaces. The task should be to bring into existence thousands or millions of new workplaces in the rural areas and small towns in order to maximize work opportunities for rural dwellers.
For this proposition to make sense, first, the work opportunities should be created in the rural areas where the majority of the people live, not where they tend to migrate for lack of opportunities. Second, the production method employed must be relatively simple, so that the demands for high skills are minimized not only in the production process itself but also in matters of organization, raw material supply, financing, marketing and so forth. Third, production should be mainly from local materials and for local use. Lastly, rural workplaces should be cheap enough so that they can be created in large numbers. These four requirements together meet the description of what is usually called ‘cottage industry’. Millions of them are needed for rural transformation in Nigeria and to check the dangerous process of mutual poisoning between urban and rural areas in the country.