to its manufacturer, Nalg Nunc, a popular line of water bottles
sold for hiking and other recreational outdoor uses is made
of polycarbonate plastic (sold as LEXAN).
scientific findings link polycarbonate water bottles to
chromosomal aberrations, thus raising questions about the
safety of consumer product made with polycarbonate, especially when
they are designed to contain food or water.
tests on bisphenol A leaching have been carried out specifically
on Nalgene water bottles, to the knowledge of www.OurstolenFuture.org,
nor were Nalgene bottles the brand used in the experiments
demonstrating a link between polycarbonate and chromosomal aberrations.
There may be some reason why Nalgene bottles do not leach bisphenol
A. This would be highly unexpected, however, given their chemical
of the research
research on chromosome damage, by a team of Case Western Reserve
scientists, found that bisphenol
A leaching out of polycarbonate bottles used to provide water
to mice caused a chromosomal error in cell division called aneuploidy.
In humans, aneuploidy is the biggest cause of miscarriages
and birth defects, including Down Syndrome, that has been identified.
aneuploidy, cells wind up after cell division with the wrong
number of chromosomes. Aneuploidy is thought to be a result
of the failure of chromosomes to align properly during a crucial
stage of cell division. Biphenol A interferes with chromosomal
upper, untreated cell has chromosomes aligned properly. The
lower cell has been treated with bisphenol A. Chromosomes
are scattered throughout the cell. They are unlikely to be
properly apportioned to daughter cells during cell division.
from Hunt et al.
scientists discovered the impact of bisphenol A by accident. A harsh
detergent was used to wash water bottles for the mice in experiments
exploring why aneuploidy becomes more common in older women. This
accident caused an 8-fold increase in the aneuploidy rate in the
mice. Subsequent research confirmed that the cause was bisphenol
A leaching out of the polycarbonate bottles, and that much smaller
amounts of the contaminant were sufficient to increase the rate
of chromosomal errors.
on the accident
studies have determined that it doesn't take exposure to harsh
detergents to cause bisphenol A to leach out of polycarbonate. The
older the plastic is, the faster the leaching rate. Heating also
increases the amount of the contaminant that escapes.
scientific studies have not yet proven with certainty that bisphenol
A causes aneuploidy in people. Yet the process of cell
division in mice is very similar to that in humans, and scientists
suspect that the causes of aneuploidy should be similar if not identical.
In addition, a range of
earlier laboratory studies already link bisphenol A to other
harmful effects, including alteration of the male reproductive tract,
hurrying puberty and reducing the effectiveness of prostate tumor
is certain is that aneuploidy causes more miscarriages and birth
defects in people than any other known factor. Hence the strong
evidence linking bisphenol A to aneuploidy in mice suggests that
measures to reduce human exposures to this contaminant are now warranted.
other words, if you have the choice, avoid water bottles made out
laboratory accident also suggests that if you are compelled to use
polycarbonate water bottles, then at the very least, do
not expose them to harsh chemical conditions. Unfortunately,
as of 12 April 2003, that is precisely what the manufacturer of
Nalgene water bottles is recommending for its products: washing
with bleach when staining occurs (see image below).
noted above, there may be something unique to Nalgene bottles that
makes them chemically different from standard polycarbonate. On
the basis of published information, there is no reason to expect