The IEUBK model is a tool developed by the US EPA to
determine blood lead levels in children.
It is used to determine the blood levels in a hypothetical child or in a
population. The results can than be
applied to estimate how much lead a child has been exposed to. This is such a critical tool because we see
IQ levels drop at very low concentrations of lead, along with other health
effects. Lead has been used in industry
and products for quiet some time, although it is not as prevalent anymore. However in older homes that were painted with
lead paint at one point, we still see an unacceptable level of lead. Even some toys coming from countries like
China, are sold in US market with very high levels of lead. This is dangerous because a child could be tempted
to chew on this, and the lead would enter their body.
The four components of the IEUBK model use
mathematical and statistical components to create a probability. The model accepts exposure data on an annual
basis to become more accurate. Comparing
predictions with real world data is vital.
It is crucial to the EPA that the modeling mechanisms are understood for
the most accurate data possible. It is very difficult to make the mathematical
relationships capable of being translated into computer code. The model has been internally and externally
validated, and is a useful tool for many purposes. The EPA superfund sites use this model on
there projects all around the country.
There are some limitations to the model, but in most cases it proves appropriate. While experimenting with the model myself, I
can see its usefulness. It is
unpractical to be able to test the blood lead level of every child, and this is
a great tool in making that estimate.
Monday, December 5, 2016
Thursday, December 1, 2016
Air Pollutants
Pollution, its something we as Americans hear about almost
everyday. It is a hot topic up for
debate when concerning how we regulate it.
But there is one thing about pollution that isn’t up for debate, and
that’s the fact it is bad for humans.
Not only is it bad for us in terms of it destroying our environment, but
it’s actually bad for our bodies too.
There are all sorts of types of pollution in today’s world. Whether that be air pollution, water
pollution, light pollution, or sound pollution.
Humans have produced a truly alarming amount of pollution, and it seems
to follow the laws of karma, in that it comes back to hurt us. We have only seen the tip of the iceberg in
how this will affect us in the future, but I will tell you in some ways it
already is. Most of the time when we
hear the word “pollution” we tend to think air pollution. A stereotypical image of a smoke stack comes
to mind for most.
And this is in fact
how we release a lot of pollution. But
what is coming out of these factory smoke stacks? Well for starters, its safe to say none of it
is good. Hundreds of thousands of
manufacturing processes in the world create a wide array of chemicals that
become entrained in our air. One of the
oldest forms of air pollution is from burning coal. This releases a spew of harmful chemicals
into our air. And it’s hard to not talk
about this type of pollution without mentioning CO2. Carbon dioxide is all around us, you are in
fact breathing it in right now. But it
isn’t CO2 that is harmful to our health, more as the effects it has on the
environment. But some pollutants, like
leaded gasoline combustion, really impact us on a personal level. In the US, we no longer use leaded gas, but
it wasn’t always that way. Lead was
thought to benefit the way the motors of our cars ran. It seemed to increase power and decrease gunk
build up. But it was entraining copious
amounts of lead in our breathing zones.
Elevated lead levels could be found in people everywhere. Especially children, and in urban areas. This lead could also become trapped in our
water, giving us a double dose. You can
still detect the lead emitted from this area in some soils across the
world. But its not just lead that was
bad for our health, countless other chemicals like the C8 released by DuPont
even today are showing negative health results.
The only way to combat this is to increase pollution regulations on
industry. However, with the electron of
Donald Trump, many fear that the US may be going the opposite direction. De-regulating industry is dangerous, and many
industry specialists have warned other countries may follow if the United
States does in fact do this. We used to
say we want to take care of the planet for our children and grand children. But it appears the effects of our pollution
are already harming our bodies on many levels, in people all around the
world.
Biological Toxins
In biology, poisons/toxins are
substances that cause disturbances in organisms’ life functions, usually by
chemical reaction or other activity on the molecular scale, when an organism
absorbs a sufficient amount of the substance.
There are all types of biological toxins and poisons all around us. Many of which are produced in the natural
world. A good example of this is the
toxins found in plants and animals.
Usually, evolution develops these toxins as a sort of defense mechanism
for the organism. We see this in snakes
all over the world. Rattlesnakes, which
are found throughout the United States, carry a very powerful toxin. The toxin is used as a defense mechanism and
to kill its prey. While a rattlesnake
hunts relatively small prey, it can easily kill animals much bigger than them,
for example a human. Plants all over the
world contain poisons/toxins that can also kill humans. Rainforest especially, contain the highest
number of poisonous plants. These plants
also have a pretty substantial role throughout history. Since the early times of human civilization,
poisoning has played a role in politics.
Serving as a tool of eliminating a political enemy, hundreds of
significant people have fallen victim to this.
People have also fallen victim to toxins on accident forever. Simply eating the wrong plant can kill
someone. Sometimes this takes minutes,
or sometimes the toxins accumulate over years and lead to death. Poisons and toxins can do some pretty scary
things to the body. This ranging from
not allowing blood cells to bond to oxygen, suffocating the victim, to actually
rotting the tissue. An animal we don’t talk
about to often as being “poisonous” is a fish.
The puffer fish, a Japanese delicacy, has poisonous organs. Certain types of crabs have toxic lungs. This is to discourage other animals from
eating them. Although this has to be a
learned behavior often, and the predator may not find out until it is too
late. Other animals that do not produce
toxins, have found a fascinating way of using them to there advantage. Many animals have adapted to being able to
tolerate the toxin of a lower life form, be it plant or animal. They then accumulate the toxin in their own
bodies, and use it to their defense. But
it’s not just animals in nature that use these toxins to there advantage. Humans have figured out many toxins, have a
therapeutic and even healing affect. For
example, universities all around the world are looking at the possible healing
effects of rattlesnake venom. And not
only that, we have even used these venoms to reverse engineer anti-venoms. These anti-venoms have saved countless people
all around the world. And it has even
gave rise to an entirely new industry, snake milking. Snakes can be farmed for this, or milked in
the wild. Some plant toxins are being
looked at for cancer research. Reason
being, researchers want to modify the toxin to target, and kill cancer
cells. This can be a much less harmful
treatment than radiation methods.
Regardless if these biological toxins scare us, or excite us with
potential, we still have a lot to learn about them.
Monday, November 7, 2016
Ames Test
The Ames test was created in
the 1970s by a man name Bruce Ames. The
Ames test is a method to figure out if any chemical is a mutagen. This can be a
pesticide, food additive, etc. This also
means that it can be a potential carcinogen.
In fact, if a chemical is a mutagen its chances of being a carcinogen
are actually quiet high. One of the
bigger benefits of the Ames test is that is relatively easy, low cost, and
quick to come to results. A strain of
salmonella is used to perform the test.
The strain of bacteria already has a mutation in its DNA. Essentially these bacteria do not survive if
you do not provide them with a certain enzyme.
The organisms are not capable of creating the enzyme as they normally
would. So the next step is you interact
a chemical with these bacteria. You do
not provide the enzyme essential for them to live. So if you add this chemical to the organism,
and it lives, that means that the bacteria actually mutated to survive. In other words, that chemical is considered a
mutagen because the only reason the bacteria lived is because it mutated.
Now this does seem a little counterintuitive,
being that the most obvious mutation is actually just being alive. So after Ames found this out, we started to
test food additives. We discovered
around half of all food additives at the time were mutagens. Now Ames being the great scientist he is said
we need to also test all natural foods.
And in some cases we found that these natural foods had more carcinogens
that the unnatural ones. However these
carcinogens are far milder, mostly negligible.
Were as unnatural foods often had lower amounts of mutagens, but they
were much more potent. Ames explained this essential by siting the survival of
the fittest theory. Meaning the plants
that survived, and were not eaten by insects, were likely to have higher
mutagens. These natural mutagens for
example are produced in some cases to kill an insect that may be the thing
eating the plant. Again, this sounds
pretty counterintuitive, but this by no means is to say that natural foods are
less healthy than their pesticide sprayed counterparts. So why are mutagens often carcinogens. Well if you know anything about cancer you
know that it is result of a mutated cell reproducing. Essentially spreading the cancer or growing
the tumor the cell may be a part of. So
some mutagens can cause this down the line.
In this scenario we consider them a carcinogen, or any chemical that causes
cancer. Just recently we even listed
processed meat, as a carcinogen. In fact
there are carcinogens all around us we may not be aware of. Many cleaning products for example contain
carcinogens, but often times there effects are negligible. This can either be because they are just not
very potent, or because they are not usually ingested by humans. Overall the Ames test has revolutionized the
way we look at mutagens in our everyday lives.
It has supplied us with a huge amount of knowledge concerning the world
in which we live everyday.
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