On living in an arsenical atmosphere (Part 2). Clinical observations, animal experiments and ecological problems.
Humans and other animals living in an arsenic polluted atmosphere appear to absorb very little through their lungs, but absorb a varying quantity through the gut. A measure of human absorbtion is reflected in that excreted in the urine, but the amount excreted correlates poorly with clinical toxicity. Symptoms of toxicity my exist at as low a level as 0.25 ppm, with clearing of the problems when the patient is treated with BAL. On the other hand, people excreting well over 1 ppm may be free of any symptoms or signs. There is an indication that arsenic does not pass from the human mother for foetus or infant, either through the placenta or through the milk. Experimental animals living in an arsenical atmosphere thrive if fed uncontaminated food, but die rapidly if fed herbage gleaned from the contaminated area. The countryside subtended by atmospheric arsenical pollution becomes seriously ecologically down graded, with high arsenic levels in soil and on foliage. Most of the flora fail to thrive, while there is virtual disappearance of the natural fauna. Once the pollution has ceased, it would appear that the arsenic is rapidly leached away, with a return to ecological normality this recovery was surprisingly rapid and complete. There is statutory provision for closure of polluting industry. Indecision, unwillingness to cut off a source of national wealth, the question of employment, and an apparent lack of serious human toxicity allowed the continuation of the mining and roasting operation until the exhaustion of a payable orebody.