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The answer is Hydrogen Sulphide
Hydrogen sulphide can corrode metals such as iron, steel, copper, and brass,
tarnish silverware, discolour copper and brass utensils, cause yellow or black
stains on fixtures, discolour beverages made with water containing it, and alter
the appearance and taste of cooked foods.
Hydrogen sulphide is a clear, colourless gas that can be identified in relatively
low concentrations, by a characteristic "rotten-egg" odour. H 2 S may accumulate
in low areas and pose a suffocation risk in areas such as well pits and cisterns.
Hydrogen sulphide odours can be recognized in low concentrations. The odour
of hydrogen sulphide will increase as the gas becomes more concentrated. At
very high levels no odour may be detected by smell. All safety procedures
should be followed before entering a confined space.
vindori answered the question on September 30, 2018 at 12:03
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