Long term effect of DDT?

     In Tzaneen, Limpopo Province, South Africa a study was conducted to find if the males sperm count was effected by the environmental expouser of DDT. There conclusion did not find a positive effect of DDT. My question to the researcher is regarding the results they published. So, what is the normal semen count in a male? Does it matter the age of the person? Did they compare this to other village or to other people in the same village who were not exposed to DDT. Using World Health Organization criteria may not be a good thing, because they are lumping everybody in there pool. They need to do more soil sampling to find if there are any presence of DDT in the soil
 around the village.









Reference:

The long-term effects of DDT exposure on semen, fertility, and sexual function of malaria vector-control workers in Limpopo Province, South Africa.

Dalvie MA, Myers JE, Thompson ML, Robins TG, Dyer S, Riebow J, Molekwa J, Jeebhay M, Millar R, Kruger P.

Source

Occupational and Environmental Health Research Unit, School of Public Health and Family Medicine, Medical School, University of Cape Town, Anzio Road, Observatory, 7925 Cape Town, South Africa. aqiel@cormack.uct.ac.za

Environ Res. 2004 Sep;96(1):1-8.