Through stoichiometric calculations, we are able to determine the number of moles, mass, concentration and volume of an unknown product or reactant in a chemical reactions. Knowing how much of a substance is present within another substance is essential for industrial safety, workplace safety, and in the case of consumer products, our own personal safety.
It has recently been discovered that the water in plastic water bottles contains a higher concentration of Antimony (a chemical similar to lead) the longer they sit in the bottle. Even though the water bottles have a safe initial antimony concentration of 160 parts per trillion after six months of sitting in the plastic that concentration doubles. This level still meets the Health Canada standards for drinking water, and advocates for bottled water companies’ state that there is no adverse affect on human health.
Still, these findings have important implications for overseas shipping. New regulations may need to be installed for the testing of bottled water for periods of time longer than 6 months, such as intercontinental transport. Antimony can cause nausea, dizziness, depression and death. Given that 20% of Canadians drink bottled water, more detailed research about the concentration of other chemicals in water over time, the effects of these chemicals on children and the elderly, and the general impact of bottled water on human health may be the next frontier.
This poses an interesting question about how cautious we need to be about the chemicals we consume. Should we take the bottled water companies’ and Health Canada’s word for it, or is the increase in a dangerous chemical in a commonly consumed product worth further investigation? How much, and what kind of additional research should be done? If the levels of Antimony are found to be unsafe after sitting for more than six months, should bottled water companies be found criminally guilty of malpractice?