The text boxes in the left panel have been placed in a random order. Restore the original order by dragging the text boxes from the left panel to the right panel.
b) Naturally occurring arsenic leaches into water from surrounding rocks and once in the water supply it is both toxic and carcinogenic to anyone drinking it.
a) Natural arsenic pollution affects 21 countries across the world sometimes reaching a concentration more than ten times the WHO guidelines.
d) Arsenic is now recognized to be one of the world’s greatest environmental hazards, threatening the lives of several hundred million people.
c) It is colourless and odourless and consequently people use it instead of more obviously polluted surface water.