Posts Tagged ‘Arsenic’
Another Study Reveals Why Our System of “Safe Levels” is a Tragic Mirage
Gas well, cement plant, lead smelter, plastics plant, refinery, compressor, incinerator. Anyone who's ever lived next door to an industrial polluter knows there's the way the facility appears to be operating on paper and how it's actually operating in the real world.
The way it's operating on paper is completely portable. You can take this version of the facility anywhere. The numbers and printouts and charts can show up to congressional hearings. They can be included in PowerPoint presentations, along with glossy pics of the place itself. They can be summarized. They have no smell. They have no texture. They don't make a sound. On paper, expressed in language and figures, the facility may seem to be operating properly under every permitted limit it has to abide by.
On the ground however, it may be a completely different story. It may mean strange petrochemical or plastic smells wafting through your house in the middle of the night. It could mean a series of loud explosions or pops that nobody has ever been able to explain to you. It could mean rashes on your skin, or headaches, or nausea, or asthma attacks. It could mean living in fear of chemical assault. All the time.
This version of operations is not portable. One can write about it or talk about it, but that will not put other people there. And indeed, descriptions of these circumstances can sound so nightmarish that listeners assume you're exaggerating. You're not. Not even video or film can immerse you in it. No amount of reporting about it can make you feel in it. The map is not the place. The only way to know this side of operations is to live it. Day in, day out.
The difference between what the paper version of polluting says, and what the people living it know, is a front line of social justice in the 21st Century.
It also happens to be a major frontline for science, as demonstrated by a recent landmark study from, of all places, Texas Tech about how the sum of pollution is greater than its sometimes desperate parts We're late in covering this, but thanks to the Denton Record Chronicle's for bringing it to our attention back in June. Because this study underscores once again in a big way why our entire system of regulating chemical exposures is so completely contrary to what we know about how those exposures are affecting us.
Tech scientists took two chemicals that are known to cause cancer in large amounts, arsenic and estrogen, and exposed human prostate cells to very low amounts of each. The amounts they exposed the prostate cells to were so low, they fell below the EPA regulatory "safe" level that limits releases of the chemicals from polluters. Individually, the exposures of the cells to arsenic and estrogen were so low as to believed to be harmless. But they weren't.
Instead, the Tech researcher's peer-reviewed, journal-published study found the combination of the low doses of the two chemicals combined was almost twice as likely to create cancer in the prostate cells as the single chemical exposures individually. That is, the toxic interaction or "cumulative effect" of the two chemicals was more than the sum of their parts. There was a "synergestic" reaction inside the cells that the current regulatory system doesn't recognize as even a possibility.
“The majority of cancers are caused by environmental influences,” Singh said. “Only about 5 to 10 percent of cancers are due to genetic predisposition. Science has looked at these chemicals, such as arsenic, and tested them in a lab to find the amounts that may cause cancer. But that’s just a single chemical in a single test. In the real world, we are getting exposed to many chemicals at once.”
Singh became interested in looking at arsenic because water well problems in his native India had recently highlighted mass poisonings from contamination of the chemical. He wondered how this exposure would interact with other carcinogens within the same population.
He focused on estrogen as the second chemical because of the chemical’s ubiquity. Many plastics, such as food can liners, release bisphenol A (BPA), and other chemicals that mimic estrogen in the body.
Unlike more potent chemicals that do major damage to the DNA in a cell, such as benzene, arsenic and estrogen aren’t major mutagens Singh said. Instead, their presence tends to stop certain genes from expressing. The process is called DNA hypermethylation.
…the two chemicals stopped the MLH1 gene, which is responsible for sending the signal to start the self-destruct sequence when a cell is damaged. Because the self-destruct couldn’t activate, the cells became cancerous after exposure.
“With the lower dose not killing the cell, it’s causing damages that go under the cell’s radar. We found when you have two compounds together, lower doses could be more serious problem.”
This is what's called a non-linear impact. You can actually get harmed more by long term low-level exposures than by intense bursts of short term exposure – exactly the opposite of the way the system regulates chemical exposures now.
Currently that system assumes it can protect the public health from exposures to over 80,000 chemicals on the marketplace by regulating the average intake of these chemicals one at a time. It says: "we know that lead and benzene are bad for you if you OD on them, but by only exposing you to a little bit every day, we can keep you from getting damaged by its health effects." The dose is the poison. A little bit cant hurt you, but a lot can kill you.
Unfortunately, this view, which is the foundation for all modern regulatory schemes for chemical pollution, is based on a worldview of human physiology that's now dangerously out of date. For the past 50 years at least, study after study has shown that there are a lot of less-than-drop-dead health effects that couldn't be diagnosed without modern technology. The more we learn about how how bodies work the more we learn new ways about how chemicals can really screw them up. The Tech study is just the latest, albeit dramatic example.
Moreover, of those 80,00 chemicals only about 200 can be said to have been studied even remotely "thoroughly" and fewer that that have been examined for their interactions with any of the other 79,999. So the system itself is a big fat theory in progress, with very little real science supporting it. We're all its Guinea Pigs. It's an hypothesis.
But its a hypothesis with billions invested in it. So to prove it wrong is to threaten a lot of people with a lot of money.
Which is why the chemical industrial-government complex is trying very hard to hold back the tide of this kind of science and what it means. Meanwhile the gap between the paper version of how things are operating at a facility and the real world impact of those operations continue to grow. At some point the contradictions will be too much to ignore or withstand. But we're a long way from that point yet. Which is why we need your help to keep fighting on behalf of those folks living the truth on the ground and prevent more victims of this obsolete and harmful regulatory system.