A complex situation of chemical exposure has been described in México in a zone that is in transition from rural activities towards intensive industrialization, which has brought environmental pollution: chloroform, methylene chloride, indigo and toluene are some of the pollutants found in the Atoyac and Xochiac rivers. A biomonitoring study was planned in order to establish whether there was a biological effect due to the environmental situation. Communities where leukaemia and thrombocytopenic purpura cases have been reported were included in the study, as well as other communities where such cases have not been described. Three occupations were distinguished, according to chemical exposure: industrial workers, agricultural workers and workers in households, education and commerce. A comprehensive analysis in the micronucleus (MN) test was used to study genotoxicity biomarkers. Two metabolic polymorphisms were determined, namely, glutathione transferase mu1 (GSTM1) and theta1 (GSTT1), which are relevant when oxidative responses are involved. Increased genotoxic damage was found, including cells with >1 MN, >1 chromatin bud, and nucleoplasmic bridges. The genotoxic damage was differentially distributed in the regions studied, being more affected those that are closer to the Atoyac and Xochiac rivers, indicating an effect due to environmental exposure to the contaminants present in the rivers. Further characterization of the exposure regimes in these communities will be done in order to contribute to the alleviation of the health risks that environmental pollution is posing on the inhabitants of this area.

Infection of rat liver by Taenia taeniformis metacestodes produced an increase in total CYP450 content and induced activity of the CYP1A1, CYP2B1 and COH isoforms. Variations in activity and p450 total content were found with increasing time of infection. During increased activity of p450 isoforms, rats were challenged with carcinogens metabolized by the mentioned isozymes and an increased amount of genotoxic damage was found when benzo[a] pyrene, cyclophosphamide and aflatoxin B(1) were used. No change was seen in CYP2E1 activity. These results support previous findings regarding an increased susceptibility to genotoxic damage of infected organisms.

Micronuclei and other biomarkers were evaluated in oral cells from 11- to 16-year-old girls living in a foster home in the central area of México City. Variables analyzed for possible association with these biomarkers include smoking habits, body mass index, metabolic polymorphisms for NAT1 and GSTM1 and whether the cells were obtained from the cheek or pharynx. The results indicated that individuals having the NAT1*10 homozygous genotype showed a significant increase in chromatin buds and binucleated cells. When the damage in the cheek was compared with damage in the pharynx, a significant increase in micronuclei and binucleated cells was found for the latter tissue in all the individuals analyzed.

La ciencia antropológica, tomada en sentido amplio de ciencia general del hombre, tiene aplicaciones de un alcance más humano y más universal que las otras ciencias de la naturaleza. Por que el hombre es el "centro común " de todas nuestras preocupaciones y los seres humanos constituyen las únicas entidades reales y tangibles que encarnan necesidades—sobre todo necesidades, necesidades materiales y espirituales—, tendencias y aspiraciones. De aquí que para el hombre ningún conocimiento sea más sugestivo a la vez que más eficaz que el conocimiento de sí mismo a través de todas las situaciones posibles de considerarse.