The high duty of scientists

A while back I had an interesting conversation with one of the janitors in our building. She is a sweet lady, and I enjoy talking to her very much. We were discussing coming back from the weekend and starting up work again. I told her a little of what I had done, and I flippantly mentioned how mundane my research had been the last couple days. Her response knocked me off my feet. She said that she knew it was really important, and that it was well worth the money and time. This is even though I have never told her what I actually do! She said a few other things, and then left. I realized that she has a very high view of the importance of research.

She has the belief that all research we do is for the betterment of humanity. I think about that, and I wonder if all of the research I do follows in line with this thought. My work on Arsenic, I believe, certainly does fit. Healthy water means healthier people. My other research on landfill leachate seems to also. I wonder though how well my research on Asphalt moisture damage fits….hummm….well, longer lasting roads mean improved infrastructure and saves money. To be honest I really dont give a rip about science for the sake of science. All that matters to me is whether it is improving lives.

If we were to apply this litmus test, “Is the research you do related to the betterment of humanity?” to all researchers I wonder how many would easily say yes, and how many would be forced to take a step back. The vast majority of the research I have seen certainly passes this test with flying colors, but then again I am in Environmental Science and Toxicology. One would hope most of our research is based on human needs.

Endocrine Disrupting Compounds; Bisphenol-A, Phthalate Esters, Dioxins, and lots of others

One hot topic you may hear about in Environmental Science and Toxicology are Endocrine Disrupting Compounds. They have been all over the news in the last 10 to 15 years. You might have heard about fish and guppies spontaneously changing sex or baby bottles releasing chemicals after being heated in the microwave. These are two examples of Endocrine Disrupting Compounds (EDCs).

Endocrine systems of animals and humans are very complex, and rely on the ability to send and receive ‘messages’ in the form of hormones inside cells. When part of a cell sends a message in the form of a hormone to another part of the cell it is called the messenger. The portion that receives the information is called the receptor. This message tells the cell to perform a specific biological task such as growth or reproduction or embryonic development⁴.

An Endocrine Disrupting Compound is therefore a compound that interferes with the communication. Some compounds can mimic hormones and therefore produce normal but untimely responses. Others are antagonistic and disrupt the normal functions by binding to the receptor thus blocking other messages or by interfering with the way hormones are made and controlled.

EDCs are very controversial within the scientific community. It is not controversial that certain organic compounds can disrupt the endocrine messaging process, but there is great controversy as to whether the dose/response relationship of tests accurately models real life. Let me explain. In the lab scientists often spike samples with high doses to see the results. In the environment animals are almost never subjected to very high concentrations^7.8. This leads to the question of whether EDCs can be additive with time (i.e. low dose long time=high dose short time) or whether different EDCs can be synergistic (i.e. work together).

There are many different types of EDCs around. Here is a table of some of the most well known.

Some Endocrine Disrupting Compounds
Category	Name	Some Sources
Alkylphenols (Surfactants)	Nonylphenol, Pentylphenol, octylphenol, nonylphenol mono and diethoxylates	Industrial and municipal effluents
Bisphenolic Compounds	Bisphenol A	Used in the synthesis of polycarbonate plastic and epoxy resins
Natural Hormones/ Synthetic Steroids	17-b-estradiol, estrone, Testosterone; ethynyl estradiol	Municipal effluent and agricultural runoff
Organochlorine Pesticides	DDT, dieldrin , lindane	Agricultural runoff, Atmospheric transport
Organotins	Tributyltin	Shipping Harbors; Used in: Wood Preservative, Antibiofouling Agents
Pesticides	Atrazine, trifluralin, permethrin	Agricultural runoff
Phthalates	Dibutyl phthalate, butylbenzyl phthalate, phthalate esters	Industrial effluent
Phytoestrogens	Isoflavones, ligans, coumestans	Pulp mill effluents
Polybrominated Compounds	Polybrominated diphenyl ethers	Flame retardants
Polychlorinated Compounds	Polychlorinated dioxins, polychlorinated biphenyls	Landfills Used in: Coolants, Insulating Fluids, PVC Pipes, Flame Retardents, etc.

Source 4,6

That is all I will write about Endocrine Disrupting Compounds in this post. I will try to write descriptions of each of these soon. Look for links.

1. Bisphenol-A: an estrogenic substance is released from polycarbonate flasks during autoclaving; AV Krishnan, P Stathis, SF Permuth, L Tokes and D Feldman; Endocrinology, Vol 132, 2279-2286, Copyright © 1993 by Endocrine Society

2. Relative binding affinity-serum modified access (RBA-SMA) assay predicts the relative in vivo bioactivity of the xenoestrogens bisphenol A and octylphenol; S C Nagel, F S vom Saal, K A Thayer, M G Dhar, M Boechler, and W V Welshons; Environ Health Perspect. 1997 January; 105(1): 70-76.

3. A physiologically based approach to the study of bisphenol A and other estrogenic chemicals on the size of reproductive organs, daily sperm production, and behavior; vom Saal FS, Cooke PS, Buchanan DL, Palanza P, Thayer KA, Nagel SC, Parmigiani S, Welshons WV.; Toxicol Ind Health. 1998 Jan-Apr;14(1-2):239-60

4. Endocrine Disrupting Substances in the Environment; Environment Canada; http://www.ec.gc.ca/eds/fact/broch_e.htm

5. Phthalates, Alkylphenols, Pesticides, Polybrominated Diphenyl Ethers, and Other Endocrine Disrupting Compounds in Indoor Air and Dust; Ruthann A. Rudel, David E. Camann, John D. Spengler, Leo R. Korn, Julia G. Brody; Environmental Science & Technology

6. Analysis and environmental levels of endocrine-disrupting compounds in freshwater sediments; Mira Petrovi , Ethel Eljarrat, Maria J. López de Alda and Damià Barceló; Copyright © 2001 Elsevier Science B.V.

7. Endocrine disruptors and reproductive development: a weight-of-evidence overview; RL Cooper and RJ Kavlock; Journal of Endocrinology, Vol 152, Issue 2, 159-166

8. Endocrine Disruptors and Human Health-is there a problem? An update.; Stephen H Safe; Environmental Health Perspectives, Vol. 108, Number 6, June 2000

Mercury Poisoning Factbox

Mercury is a very common contaminant found in a variety of environments. Mercury is not beneficial to the body in any amount³, is a potent neurotoxin^{6, 7}, and has been linked to autism⁵. Recently, much news has been on mercury poisoning in fish especially sushi. What are the facts on Mercury?

First, one of the central ideas of environmental toxicology is that the form of the contaminant determines its toxicity and its mobility. When told that an environment contains a certain contaminant environmental geochemists immediately ask, “What forms is it in?” The forms of Mercury are:

• Elemental Mercury (Hg⁰) – This form is volatile and is spontaneously oxidized in the presence of light
• Mercuric Ion (Hg²⁺) – salts, used in tanning and as disinfectants, kills/inhibits many microbes, toxic but rapidly excreted⁸
• Mineral (HgS) – Cinnabar
• Organic Mercurials (RHg⁺) – used as slimicide, paper industry, seed coating; two major forms are methylmercury and dimethylmercury

The form of mercury is very important in determining its toxicity. For example many of us have fillings in our teeth. Amalgam fillings are often 50% Mercury (As I type this my tongue goes to the top of my mouth and feels mine). However, it is in the elemental form Hg⁰. If your filling gets exposed to light by opening your mouth wide it is oxidized to Hg²⁺ and is almost entirely excreted through your urine⁹ (despite what some holistic medical websites may claim). Methylmercury, however, is the common type found in fish and other foods. Methylmercury is 100 times more toxic than Hg²⁺ and is very poorly metabolized and excreted from the body.

Mercury enters the atmosphere through natural and anthropomorphic sources. Some natural sources include: volcanoes, minerals, and volatilization from ocean. Some anthropomorphic sources are: coal combustion, waste incineration, dentistry, and metal processing. Most sources would say that humans have doubled or even tripled the amount of Mercury in the atmosphere¹⁰.

Through various activities, such as combustion of fossil fuels, Mercury has settled after volatilization to nearly form a blanket across the earth. Mercury has settled into the ocean sediment as well. The form is usually Hg⁰ or Hg²⁺ which is changed to methylmercury through uptake of organisms generally settling in their fatty tissue. Mercury is biomagnified as predators eat smaller fish and other aquatic animals. For this reason predatory fish will tend to have higher amounts of Mercury.

The story is not all bad. Just as Mercury can become more toxic by changing form it can also become detoxified. For instance, Methanogens (bacteria) can change Methylmercury to elemental Mercury through the reaction: CH₃Hg^+ → CH⁴⁺ Hg⁰. Another pathway is through microbes harboring heavy-metal resistance plasmids changing Hg²⁺ to Hg⁰. Lastly, Anoxic-Sulfate Reducers produce H2S ppt mercury through Hg²⁺⁺ H₂S → HgS, Hg₂S.

Mercury is most harmful to women and children^6,7, but men should be very careful as well. Fish are not harmed by the Mercury in their body. Therefore, they will accumulate Mercury without health effects to themselves. When the Mercury is transferred to humans however the effects can be drastic. One horrible example is the Minamata Disaster off of Minamata Bay in Japan in 1932-1969. Thousands of people living around the bay developed Methylmercury poisoning through the consumption of contaminated fish⁸. Mercury was dumped into the bay by Chisso plastics manufacturing company. Symptoms include tingling sensations, muscle weakness, unsteady gait, tunnel vision, slurred speech, hearing loss, and abnormal behavior, such as sudden fits of laughter. Some may remember the story of the Mad Hatter. In the mid-18th to the mid-19th centuries Mercury was used in the process of hat making through mercuric nitrate, Hg(NO₃)₂·2H₂O which was added to separated the fur from the pelt. The vapors produced were highly toxic.

1. On the Chemical Form of Mercury in Edible Fish and Marine Invertebrate Tissue Bloom, NS; Canadian Journal of Fisheries and Aquatic Sciences CJFSDX, Vol. 49, No. 5, p 1010-1017, May 1992. 1 fig, 4 tab, 22 ref.

2. Importance of wetlands as sources of methyl mercury to boreal forest ecosystems
St. Louis, VL; Rudd, JWM; Kelly, CA; Beaty, KG; Bloom, NS; Flett, RJ
Canadian Journal of Fisheries and Aquatic Sciences [CAN. J. FISH. AQUAT. SCI.]. Vol. 51, no. 5, pp. 1065-1076. 1994.

3. http://dcnutrition.com/minerals/minerals.cfm

4. Mercury methylation in aquatic systems affected by acid deposition; Gilmour CC, Henry EA, Environ Pollut. 1991;71(2-4):131-69

5. Autism: a novel form of mercury poisoning; S. Bernard, A. Enayati, L. Redwood, H. Roger and T. Binstock; ARC Research, Cranford, New Jersey, USA

6. Methylmercury poisoning: long-term clinical, radiological, toxicological, and pathological studies of an affected family; Davis LE, Kornfeld M, Mooney HS, Fiedler KJ, Haaland KY, Orrison WW, Cernichiari E, Clarkson TW; Ann Neurol. 1994 Jun;35(6):680-8

7. Iatrogenic exposure to mercury after hepatitis B vaccination in preterm infants;

Stajich GV, Lopez GP, Harry SW, Sexson WR; J Pediatr. 2000 May;136(5):679-81

8. Personal Presentations in Biogeochemistry; Texas A&M University; Dr. McGuire

9. People with high mercury uptake from their own dental amalgam fillings; L Barregard, G Sallsten and B Jarvholm; Occupational and Environmental Medicine, Vol 52, 124-128

10. Regional differences in worldwide emissions of mercury to the atmosphere; Nicola Pirrone, Gerald J. Keeler and Jerome O. Nriagu; Atmospheric Environment Vol. 30, No. 17, pp. 2981 2987, 1996; Copyright © 1996 Published by Elsevier Science Ltd

Distilled Water: An Unhealthy Choice

Distilled water is sold in stores and promoted by some health leaders as a pure natural choice for drinking water. In reality, however, it is anything but natural, and is likely very detrimental to your health.

Distilled water is almost or completely free of dissolved minerals. It is created through a process of boiling and then condensing the steam into another container. This sounds like a great thing at first glance. Water in nature, however, is almost never in this “natural” state. Water can be thought of as ‘wanting’ some impurities chemically. It will act to gain them. 

When distilled water is opened to the air it immediately begins reacting with what it comes into contact with. Initially it reacts with CO₂ in the air creating Carbonic Acid (H₂CO₃) lowering the pH making the water more acidic. Distilled water is very aggressive. In the desalination industry it is an industry-wide rule that water must be partially remineralized before sent down the distribution pipeline because the purified water is too aggressive and will cause severe corrosion of the pipeline². One study of a desalinization plant in Cyprus found that iron was being leached from the pipes the distilled water was traveling through³.

It has been shown that drinking low mineral water creates a net loss of nutrients in the body^1,2. The nutrients are leached from the body by distilled water. Some sellers of distilled water have claimed that nutrients in the body are somehow protected from the effects. This would be nice, but animal and human studies show that it simply does not work that way. Some other health effects have been correlated to drinking distilled and deionized water such as¹:

•  Direct effects on the intestinal mucous membrane, metabolism and mineral homeostasis or other body functions.
•  Low intake of other essential elements and microelements.
•  Possible increased dietary intake of toxic metals

1. Nutrients in Drinking Water; Water, Sanitation and Health Protection and the Human Environment World Health Organization Geneva; World Health Organization 2005 

2. Water—The Choice for Long-Term Health; Michael Donaldson

3. First desalination plant in Cyprus — product water aggresivity and corrosion control; Marangou VS, Savvides K. Desalination 2001;138:251-258.

4. Human milk calcium and phosphate levels of mothers delivering term and preterm infants; Chan GM.; J Pediatr Gastroenterol Nutr 1982;1(2):201-5.

5. Variations in the mineral concentrations in breast milk during a single nursing, diurnally and on consecutive days; Gillies ME, Neill AE.; Hum Nutr Appl Nutr 1985;39(5):370-5.

6. Serum zinc and demineralized water; Robbins DJ, Sly MR, du Bruyn DB.; Am J Clin Nutr 1981;34(5):962-3.

7. Measured consumption of tap water in German infants and young children as background for potential health risk assessments: data of the DONALD Study; Hilbig A, Kersting M, Sichert-Hellert W.  Food Addit Contam 2002;19:829-836. 

8. The most essential nutrient: Defining the adequate intake of water; Manz F, Wentz A, Sichert-Hellert W. J Pediatr 2002; 141:587-592. 

9. WHO and World Health Organization. Guidelines for drinking-water quality. Health criteria and other supporting information. Geneva: WHO, 1996.

Why Westerners Are The Wastrels Of The World

Ok, so I have to put this article up. Check this out.

http://www.newstarget.com/022424.html