Human Population Monitoring

Crow, J.F. Human population monitoring, pp. 591-605. In A. Hollaender, Ed. Chemical Mutagens Principles and Methods for Their Detection. Vol. 2. New York Plenum Press, 1971. 

In vitro SCE assays are routinely conducted in cultured Chinese hamster ovary (CHO) cells or human lymphocytes, and assessments of SCEs in human lymphocytes have been used for human population monitoring. Following in vivo exposure, SCEs are usually visualized in bone marrow cells from mice implanted with BrdU-containing tablets (or pumps). Such SCE assays have been used to test several hundred chemicals and have been shown to be highly sensitive and, in comparison to conventional assays for chromosomal aberrations, to be more rapid, less subjective, and capable of detecting effects at lower dose levels. 

Lambert, B., Lindblad, A., Holmberg, K. and Francesconi, D. (1982). The use of sister chromatid exchange to monitor human populations for exposure to toxicologically harmful agents. In Sister Chromatid Exchange (Wolff, S., Ed.). Wiley, New York, pp. 149-182. 

There is no clinical disease state unique to heptachlor. A major problem in developing a biomarker of effect for heptachlor or heptachlor epoxide is that human exposures to these compounds have occurred concomitantly with exposures to other chemicals, and it is difficult to attribute the health effects to heptachlor or heptachlor epoxide alone. More data that quantify the biological effects as well as data that distinguish heptachlor and heptachlor epoxide exposures from those of other chemicals would be useful for developing biomarkers of effect for population monitoring. Biomarkers that could indicate the length of time since exposure would also be useful. 

The technology for monitoring mutation in the human population is not yet sufficiently developed for wide application. However, there are systems that could be applied to selected populations, such as workers in a chemical factory. 

That the feasibility of genetic monitoring of the human population for chromosomal breakage and increased genetic disease be explored. 

Adaptation of the original micronucleus test to circulating lymphocytes has made it feasible to consider this test for screening of human populations.73 155 The test showed a positive dose-response relationship with x rays and mitomycin C, although in the former case the response was small below 100 R. The micronucleus test needs more study before it can be used to monitor populations. It should be useful for small numbers of persons and hence be especially valuable. 

SCE production is probably caused by S-phase-dependent chemicals. Consequently, DNA repair phenomena that remove lesions from DNA before lymphocytes cure stimulated to enter the S phase can influence the yield of SCEs just as they can influence the yield of chromosomal aberrations. Thus, DNA repair processes and other factors that influence SCE production still make the mechanistic interpretation of SCE production complicated when one is monitoring human populations for small exposure to chemicals.230... 

Neel, J.V., T.O. Tiffany, and N.G. Anderson. Approaches to monitoring human populations for mutation rates... 

In the urine of experimental animals, N-dealkyl metabolites of triazine herbicides have been identified (15,16). Methodology for the determination of these kinds of compounds is currently available (15) and should be applicable for monitoring human population. 

Monitoring body burdens of chemicals in human populations may contribute to a better understanding of what chemicals and at what concentrations they get into the body. For chemicals with known toxicity levels, it may be possible to learn the prevalence of people with concentrations exceeding those toxicity levels. However, it should be noted that most biomonitoring studies in the general population are designed as survey studies. Many of the studies do not take into account exposure history. Therefore, the results often represent a snapshot at 1 point in time. 

The large-scale monitoring studies enable researchers to track, over established time periods, trends in levels of exposure in human populations and to assess the effectiveness of public health efforts to reduce exposure to specific harmful chemicals. Aylward and Hays (2002) summarized recent trends in dioxins intake in the United States and in Western Europe. The intake estimates show clear decreases of... 

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