Mosaic large-area

Environmental toxicology is concerned with the movement of toxicants and their metabolites and degradation products in the environment and in food chains and with the effect of such contaminants on individuals and, especially, populations. Because of the large number of industrial chemicals and possibilities for exposure, as well as the mosaic of overlapping laws that govern such exposure, this area of applied toxicology is well developed. 

In humans these cycles occur in a relatively random fashion in the follicles at various sites of the body. In certain animals, e.g., the mouse or rabbit, the hair cycle is largely synchronized with regional waves of growth and loss leading to readily discernible areas of hair loss. Other animals are more mosaic (like humans) in their cycles. It is likely that patterns of cycling occur in humans the anterior hair line is one probable candidate. Identifying these minor areas of synchrony in humans has been difficult. 

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